Commit Graph

35781 Commits

Author SHA1 Message Date
Dmitrii Banshchikov 4ddb74165a bpf: Extract nullable reg type conversion into a helper function
Extract conversion from a register's nullable type to a type with a
value. The helper will be used in mark_ptr_not_null_reg().

Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210212205642.620788-3-me@ubique.spb.ru
2021-02-12 17:37:23 -08:00
Dmitrii Banshchikov feb4adfad5 bpf: Rename bpf_reg_state variables
Using "reg" for an array of bpf_reg_state and "reg[i + 1]" for an
individual bpf_reg_state is error-prone and verbose. Use "regs" for the
former and "reg" for the latter as other code nearby does.

Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210212205642.620788-2-me@ubique.spb.ru
2021-02-12 17:37:23 -08:00
Daniel Borkmann 9b00f1b788 bpf: Fix truncation handling for mod32 dst reg wrt zero
Recently noticed that when mod32 with a known src reg of 0 is performed,
then the dst register is 32-bit truncated in verifier:

  0: R1=ctx(id=0,off=0,imm=0) R10=fp0
  0: (b7) r0 = 0
  1: R0_w=inv0 R1=ctx(id=0,off=0,imm=0) R10=fp0
  1: (b7) r1 = -1
  2: R0_w=inv0 R1_w=inv-1 R10=fp0
  2: (b4) w2 = -1
  3: R0_w=inv0 R1_w=inv-1 R2_w=inv4294967295 R10=fp0
  3: (9c) w1 %= w0
  4: R0_w=inv0 R1_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R2_w=inv4294967295 R10=fp0
  4: (b7) r0 = 1
  5: R0_w=inv1 R1_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R2_w=inv4294967295 R10=fp0
  5: (1d) if r1 == r2 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R2_w=inv4294967295 R10=fp0
  6: R0_w=inv1 R1_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R2_w=inv4294967295 R10=fp0
  6: (b7) r0 = 2
  7: R0_w=inv2 R1_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R2_w=inv4294967295 R10=fp0
  7: (95) exit
  7: R0=inv1 R1=inv(id=0,umin_value=4294967295,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R2=inv4294967295 R10=fp0
  7: (95) exit

However, as a runtime result, we get 2 instead of 1, meaning the dst
register does not contain (u32)-1 in this case. The reason is fairly
straight forward given the 0 test leaves the dst register as-is:

  # ./bpftool p d x i 23
   0: (b7) r0 = 0
   1: (b7) r1 = -1
   2: (b4) w2 = -1
   3: (16) if w0 == 0x0 goto pc+1
   4: (9c) w1 %= w0
   5: (b7) r0 = 1
   6: (1d) if r1 == r2 goto pc+1
   7: (b7) r0 = 2
   8: (95) exit

This was originally not an issue given the dst register was marked as
completely unknown (aka 64 bit unknown). However, after 468f6eafa6
("bpf: fix 32-bit ALU op verification") the verifier casts the register
output to 32 bit, and hence it becomes 32 bit unknown. Note that for
the case where the src register is unknown, the dst register is marked
64 bit unknown. After the fix, the register is truncated by the runtime
and the test passes:

  # ./bpftool p d x i 23
   0: (b7) r0 = 0
   1: (b7) r1 = -1
   2: (b4) w2 = -1
   3: (16) if w0 == 0x0 goto pc+2
   4: (9c) w1 %= w0
   5: (05) goto pc+1
   6: (bc) w1 = w1
   7: (b7) r0 = 1
   8: (1d) if r1 == r2 goto pc+1
   9: (b7) r0 = 2
  10: (95) exit

Semantics also match with {R,W}x mod{64,32} 0 -> {R,W}x. Invalid div
has always been {R,W}x div{64,32} 0 -> 0. Rewrites are as follows:

  mod32:                            mod64:

  (16) if w0 == 0x0 goto pc+2       (15) if r0 == 0x0 goto pc+1
  (9c) w1 %= w0                     (9f) r1 %= r0
  (05) goto pc+1
  (bc) w1 = w1

Fixes: 468f6eafa6 ("bpf: fix 32-bit ALU op verification")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-02-13 00:53:12 +01:00
Jun'ichi Nomura 7d4553b69f bpf, devmap: Use GFP_KERNEL for xdp bulk queue allocation
The devmap bulk queue is allocated with GFP_ATOMIC and the allocation
may fail if there is no available space in existing percpu pool.

Since commit 75ccae62cb ("xdp: Move devmap bulk queue into struct net_device")
moved the bulk queue allocation to NETDEV_REGISTER callback, whose context
is allowed to sleep, use GFP_KERNEL instead of GFP_ATOMIC to let percpu
allocator extend the pool when needed and avoid possible failure of netdev
registration.

As the required alignment is natural, we can simply use alloc_percpu().

Fixes: 75ccae62cb ("xdp: Move devmap bulk queue into struct net_device")
Signed-off-by: Jun'ichi Nomura <junichi.nomura@nec.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210209082451.GA44021@jeru.linux.bs1.fc.nec.co.jp
2021-02-13 00:11:26 +01:00
Yonghong Song 17d8beda27 bpf: Fix an unitialized value in bpf_iter
Commit 15d83c4d7c ("bpf: Allow loading of a bpf_iter program")
cached btf_id in struct bpf_iter_target_info so later on
if it can be checked cheaply compared to checking registered names.

syzbot found a bug that uninitialized value may occur to
bpf_iter_target_info->btf_id. This is because we allocated
bpf_iter_target_info structure with kmalloc and never initialized
field btf_id afterwards. This uninitialized btf_id is typically
compared to a u32 bpf program func proto btf_id, and the chance
of being equal is extremely slim.

This patch fixed the issue by using kzalloc which will also
prevent future likely instances due to adding new fields.

Fixes: 15d83c4d7c ("bpf: Allow loading of a bpf_iter program")
Reported-by: syzbot+580f4f2a272e452d55cb@syzkaller.appspotmail.com
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210212005926.2875002-1-yhs@fb.com
2021-02-12 13:33:50 -08:00
Song Liu 3d06f34aa8 bpf: Allow bpf_d_path in bpf_iter program
task_file and task_vma iter programs have access to file->f_path. Enable
bpf_d_path to print paths of these file.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210212183107.50963-3-songliubraving@fb.com
2021-02-12 12:56:53 -08:00
Song Liu 3a7b35b899 bpf: Introduce task_vma bpf_iter
Introduce task_vma bpf_iter to print memory information of a process. It
can be used to print customized information similar to /proc/<pid>/maps.

Current /proc/<pid>/maps and /proc/<pid>/smaps provide information of
vma's of a process. However, these information are not flexible enough to
cover all use cases. For example, if a vma cover mixed 2MB pages and 4kB
pages (x86_64), there is no easy way to tell which address ranges are
backed by 2MB pages. task_vma solves the problem by enabling the user to
generate customize information based on the vma (and vma->vm_mm,
vma->vm_file, etc.).

To access the vma safely in the BPF program, task_vma iterator holds
target mmap_lock while calling the BPF program. If the mmap_lock is
contended, task_vma unlocks mmap_lock between iterations to unblock the
writer(s). This lock contention avoidance mechanism is similar to the one
used in show_smaps_rollup().

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210212183107.50963-2-songliubraving@fb.com
2021-02-12 12:56:53 -08:00
Linus Torvalds e77a6817d4 tracing: Fix buffer overflow in trace event filter
It was reported that if an trace event was larger than a page
 and was filtered, that it caused memory corruption. The reason
 is that filtered events first go into a buffer to test the filter
 before being written into the ring buffer. Unfortunately,
 this write did not check the size.
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Merge tag 'trace-v5.11-rc7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Fix buffer overflow in trace event filter.

  It was reported that if an trace event was larger than a page and was
  filtered, that it caused memory corruption. The reason is that
  filtered events first go into a buffer to test the filter before being
  written into the ring buffer. Unfortunately, this write did not check
  the size"

* tag 'trace-v5.11-rc7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Check length before giving out the filter buffer
2021-02-12 11:16:17 -08:00
John Ogness 13791c80b0 printk: avoid prb_first_valid_seq() where possible
If message sizes average larger than expected (more than 32
characters), the data_ring will wrap before the desc_ring. Once the
data_ring wraps, it will start invalidating descriptors. These
invalid descriptors hang around until they are eventually recycled
when the desc_ring wraps. Readers do not care about invalid
descriptors, but they still need to iterate past them. If the
average message size is much larger than 32 characters, then there
will be many invalid descriptors preceding the valid descriptors.

The function prb_first_valid_seq() always begins at the oldest
descriptor and searches for the first valid descriptor. This can
be rather expensive for the above scenario. And, in fact, because
of its heavy usage in /dev/kmsg, there have been reports of long
delays and even RCU stalls.

For code that does not need to search from the oldest record,
replace prb_first_valid_seq() usage with prb_read_valid_*()
functions, which provide a start sequence number to search from.

Fixes: 896fbe20b4 ("printk: use the lockless ringbuffer")
Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: J. Avila <elavila@google.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210211173152.1629-1-john.ogness@linutronix.de
2021-02-12 17:54:59 +01:00
Steven Rostedt (VMware) 99e22ce73c tracing: Make hash-ptr option default
Since the original behavior of the trace events is to hash the %p pointers,
make that the default, and have developers have to enable the option in
order to have them unhashed.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-12 11:52:59 -05:00
Paolo Bonzini 8c6e67bec3 KVM/arm64 updates for Linux 5.12
- Make the nVHE EL2 object relocatable, resulting in much more
   maintainable code
 - Handle concurrent translation faults hitting the same page
   in a more elegant way
 - Support for the standard TRNG hypervisor call
 - A bunch of small PMU/Debug fixes
 - Allow the disabling of symbol export from assembly code
 - Simplification of the early init hypercall handling
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Merge tag 'kvmarm-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 updates for Linux 5.12

- Make the nVHE EL2 object relocatable, resulting in much more
  maintainable code
- Handle concurrent translation faults hitting the same page
  in a more elegant way
- Support for the standard TRNG hypervisor call
- A bunch of small PMU/Debug fixes
- Allow the disabling of symbol export from assembly code
- Simplification of the early init hypercall handling
2021-02-12 11:23:44 -05:00
Rikard Falkeborn 1556057413 PM: sleep: Constify static struct attribute_group
The only usage of suspend_attr_group is to put its address in an
array of pointers to const attribute_group structs.

Make it const to allow the compiler to put it into read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-12 16:46:59 +01:00
Lukasz Luba c4cc3141b6 PM: Kconfig: remove unneeded "default n" options
Remove "default n" options. If the "default" line is removed, it
defaults to 'n'.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-12 16:43:23 +01:00
Lukasz Luba 3af2f0aa2e PM: EM: update Kconfig description and drop "default n" option
Energy Model supports now other devices like GPUs, DSPs, not only CPUs.
Thus, update the description in the config option. Remove also unneeded
"default n". If the "default" line is removed, it defaults to 'n'.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-12 16:43:23 +01:00
Ingo Molnar a3251c1a36 Merge branch 'x86/paravirt' into x86/entry
Merge in the recent paravirt changes to resolve conflicts caused
by objtool annotations.

Conflicts:
	arch/x86/xen/xen-asm.S

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-12 13:36:43 +01:00
Ingo Molnar 85e853c5ec Merge branch 'for-mingo-rcu' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

- Documentation updates.

- Miscellaneous fixes.

- kfree_rcu() updates: Addition of mem_dump_obj() to provide allocator return
  addresses to more easily locate bugs.  This has a couple of RCU-related commits,
  but is mostly MM.  Was pulled in with akpm's agreement.

- Per-callback-batch tracking of numbers of callbacks,
  which enables better debugging information and smarter
  reactions to large numbers of callbacks.

- The first round of changes to allow CPUs to be runtime switched from and to
  callback-offloaded state.

- CONFIG_PREEMPT_RT-related changes.

- RCU CPU stall warning updates.
- Addition of polling grace-period APIs for SRCU.

- Torture-test and torture-test scripting updates, including a "torture everything"
  script that runs rcutorture, locktorture, scftorture, rcuscale, and refscale.
  Plus does an allmodconfig build.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-12 12:56:55 +01:00
Ingo Molnar c11878fd50 Merge branch 'for-mingo-kcsan' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/core
Pull KCSAN updates from Paul E. McKenney:

 "Kernel concurrency sanitizer (KCSAN) updates from Marco Elver."

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-12 12:55:33 +01:00
Ingo Molnar 62137364e3 Merge branch 'linus' into locking/core, to pick up upstream fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-12 12:54:58 +01:00
Ilya Leoshkevich b2e37a7114 bpf: Fix subreg optimization for BPF_FETCH
All 32-bit variants of BPF_FETCH (add, and, or, xor, xchg, cmpxchg)
define a 32-bit subreg and thus have zext_dst set. Their encoding,
however, uses dst_reg field as a base register, which causes
opt_subreg_zext_lo32_rnd_hi32() to zero-extend said base register
instead of the one the insn really defines (r0 or src_reg).

Fix by properly choosing a register being defined, similar to how
check_atomic() already does that.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210210204502.83429-1-iii@linux.ibm.com
2021-02-11 22:03:19 -08:00
Alexei Starovoitov 1336c66247 bpf: Clear per_cpu pointers during bpf_prog_realloc
bpf_prog_realloc copies contents of struct bpf_prog.
The pointers have to be cleared before freeing old struct.

Reported-by: Ilya Leoshkevich <iii@linux.ibm.com>
Fixes: 700d4796ef ("bpf: Optimize program stats")
Fixes: ca06f55b90 ("bpf: Add per-program recursion prevention mechanism")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-02-11 19:35:00 -08:00
Florent Revest c5dbb89fc2 bpf: Expose bpf_get_socket_cookie to tracing programs
This needs a new helper that:
- can work in a sleepable context (using sock_gen_cookie)
- takes a struct sock pointer and checks that it's not NULL

Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210111406.785541-2-revest@chromium.org
2021-02-11 17:44:41 -08:00
Masami Hiramatsu a345a6718b tracing: Add ptr-hash option to show the hashed pointer value
Add tracefs/options/hash-ptr option to show hashed pointer
value by %p in event printk format string.

For the security reason, normal printk will show the hashed
pointer value (encrypted by random number) with %p to printk
buffer to hide the real address. But the tracefs/trace always
shows real address for debug. To bridge those outputs, add an
option to switch the output format. Ftrace users can use it
to find the hashed value corresponding to the real address
in trace log.

Link: https://lkml.kernel.org/r/160277372504.29307.14909828808982012211.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-11 16:31:57 -05:00
Masami Hiramatsu efbbdaa22b tracing: Show real address for trace event arguments
To help debugging kernel, show real address for trace event arguments
in tracefs/trace{,pipe} instead of hashed pointer value.

Since ftrace human-readable format uses vsprintf(), all %p are
translated to hash values instead of pointer address.

However, when debugging the kernel, raw address value gives a
hint when comparing with the memory mapping in the kernel.
(Those are sometimes used with crash log, which is not hashed too)
So converting %p with %px when calling trace_seq_printf().

Moreover, this is not improving the security because the tracefs
can be used only by root user and the raw address values are readable
from tracefs/percpu/cpu*/trace_pipe_raw file.

Link: https://lkml.kernel.org/r/160277370703.29307.5134475491761971203.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-11 16:31:57 -05:00
Steven Rostedt (VMware) b220c049d5 tracing: Check length before giving out the filter buffer
When filters are used by trace events, a page is allocated on each CPU and
used to copy the trace event fields to this page before writing to the ring
buffer. The reason to use the filter and not write directly into the ring
buffer is because a filter may discard the event and there's more overhead
on discarding from the ring buffer than the extra copy.

The problem here is that there is no check against the size being allocated
when using this page. If an event asks for more than a page size while being
filtered, it will get only a page, leading to the caller writing more that
what was allocated.

Check the length of the request, and if it is more than PAGE_SIZE minus the
header default back to allocating from the ring buffer directly. The ring
buffer may reject the event if its too big anyway, but it wont overflow.

Link: https://lore.kernel.org/ath10k/1612839593-2308-1-git-send-email-wgong@codeaurora.org/

Cc: stable@vger.kernel.org
Fixes: 0fc1b09ff1 ("tracing: Use temp buffer when filtering events")
Reported-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-11 14:23:37 -05:00
Alexei Starovoitov 638e4b825d bpf: Allows per-cpu maps and map-in-map in sleepable programs
Since sleepable programs are now executing under migrate_disable
the per-cpu maps are safe to use.
The map-in-map were ok to use in sleepable from the time sleepable
progs were introduced.

Note that non-preallocated maps are still not safe, since there is
no rcu_read_lock yet in sleepable programs and dynamically allocated
map elements are relying on rcu protection. The sleepable programs
have rcu_read_lock_trace instead. That limitation will be addresses
in the future.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-9-alexei.starovoitov@gmail.com
2021-02-11 16:19:26 +01:00
Alexei Starovoitov 9ed9e9ba23 bpf: Count the number of times recursion was prevented
Add per-program counter for number of times recursion prevention mechanism
was triggered and expose it via show_fdinfo and bpf_prog_info.
Teach bpftool to print it.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-7-alexei.starovoitov@gmail.com
2021-02-11 16:19:20 +01:00
Alexei Starovoitov ca06f55b90 bpf: Add per-program recursion prevention mechanism
Since both sleepable and non-sleepable programs execute under migrate_disable
add recursion prevention mechanism to both types of programs when they're
executed via bpf trampoline.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-5-alexei.starovoitov@gmail.com
2021-02-11 16:19:13 +01:00
Alexei Starovoitov f2dd3b3946 bpf: Compute program stats for sleepable programs
Since sleepable programs don't migrate from the cpu the excution stats can be
computed for them as well. Reuse the same infrastructure for both sleepable and
non-sleepable programs.

run_cnt     -> the number of times the program was executed.
run_time_ns -> the program execution time in nanoseconds including the
               off-cpu time when the program was sleeping.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-4-alexei.starovoitov@gmail.com
2021-02-11 16:19:06 +01:00
Alexei Starovoitov 031d6e02dd bpf: Run sleepable programs with migration disabled
In older non-RT kernels migrate_disable() was the same as preempt_disable().
Since commit 74d862b682 ("sched: Make migrate_disable/enable() independent of RT")
migrate_disable() is real and doesn't prevent sleeping.

Running sleepable programs with migration disabled allows to add support for
program stats and per-cpu maps later.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-3-alexei.starovoitov@gmail.com
2021-02-11 16:18:55 +01:00
Alexei Starovoitov 700d4796ef bpf: Optimize program stats
Move bpf_prog_stats from prog->aux into prog to avoid one extra load
in critical path of program execution.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-2-alexei.starovoitov@gmail.com
2021-02-11 16:17:50 +01:00
Waiman Long d8d0da4eee locking/arch: Move qrwlock.h include after qspinlock.h
include/asm-generic/qrwlock.h was trying to get arch_spin_is_locked via
asm-generic/qspinlock.h.  However, this does not work because architectures
might be using queued rwlocks but not queued spinlocks (csky), or because they
might be defining their own queued_* macros before including asm/qspinlock.h.

To fix this, ensure that asm/spinlock.h always includes qrwlock.h after
defining arch_spin_is_locked (either directly for csky, or via
asm/qspinlock.h for other architectures).  The only inclusion elsewhere
is in kernel/locking/qrwlock.c.  That one is really unnecessary because
the file is only compiled in SMP configurations (config QUEUED_RWLOCKS
depends on SMP) and in that case linux/spinlock.h already includes
asm/qrwlock.h if needed, via asm/spinlock.h.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Waiman Long <longman@redhat.com>
Fixes: 26128cb6c7 ("locking/rwlocks: Add contention detection for rwlocks")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Ben Gardon <bgardon@google.com>
[Add arch/sparc and kernel/locking parts per discussion with Waiman. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 07:59:54 -05:00
Daniel Thompson f11e2bc682 kgdb: Remove kgdb_schedule_breakpoint()
To the very best of my knowledge there has never been any in-tree
code that calls this function. It exists largely to support an
out-of-tree driver that provides kgdb-over-ethernet using the
netpoll API.

kgdboe has been out-of-tree for more than 10 years and I don't
recall any serious attempt to upstream it at any point in the last
five. At this stage it looks better to stop carrying this code in
the kernel and integrate the code into the out-of-tree driver
instead.

The long term trajectory for the kernel looks likely to include
effort to remove or reduce the use of tasklets (something that has
also been true for the last 10 years). Thus the main real reason
for this patch is to make explicit that the in-tree kgdb features
do not require tasklets.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20210210142525.2876648-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
2021-02-11 10:51:56 +00:00
Marco Elver 6df8fb8330 bpf_lru_list: Read double-checked variable once without lock
For double-checked locking in bpf_common_lru_push_free(), node->type is
read outside the critical section and then re-checked under the lock.
However, concurrent writes to node->type result in data races.

For example, the following concurrent access was observed by KCSAN:

  write to 0xffff88801521bc22 of 1 bytes by task 10038 on cpu 1:
   __bpf_lru_node_move_in        kernel/bpf/bpf_lru_list.c:91
   __local_list_flush            kernel/bpf/bpf_lru_list.c:298
   ...
  read to 0xffff88801521bc22 of 1 bytes by task 10043 on cpu 0:
   bpf_common_lru_push_free      kernel/bpf/bpf_lru_list.c:507
   bpf_lru_push_free             kernel/bpf/bpf_lru_list.c:555
   ...

Fix the data races where node->type is read outside the critical section
(for double-checked locking) by marking the access with READ_ONCE() as
well as ensuring the variable is only accessed once.

Fixes: 3a08c2fd76 ("bpf: LRU List")
Reported-by: syzbot+3536db46dfa58c573458@syzkaller.appspotmail.com
Reported-by: syzbot+516acdb03d3e27d91bcd@syzkaller.appspotmail.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210209112701.3341724-1-elver@google.com
2021-02-10 15:54:26 -08:00
Thomas Gleixner db1cc7aede softirq: Move do_softirq_own_stack() to generic asm header
To avoid include recursion hell move the do_softirq_own_stack() related
content into a generic asm header and include it from all places in arch/
which need the prototype.

This allows architectures to provide an inline implementation of
do_softirq_own_stack() without introducing a lot of #ifdeffery all over the
place.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210210002513.289960691@linutronix.de
2021-02-10 23:34:16 +01:00
David S. Miller dc9d87581d Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-02-10 13:30:12 -08:00
Lakshmi Ramasubramanian f31e3386a4 ima: Free IMA measurement buffer after kexec syscall
IMA allocates kernel virtual memory to carry forward the measurement
list, from the current kernel to the next kernel on kexec system call,
in ima_add_kexec_buffer() function.  This buffer is not freed before
completing the kexec system call resulting in memory leak.

Add ima_buffer field in "struct kimage" to store the virtual address
of the buffer allocated for the IMA measurement list.
Free the memory allocated for the IMA measurement list in
kimage_file_post_load_cleanup() function.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Fixes: 7b8589cc29 ("ima: on soft reboot, save the measurement list")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-02-10 15:49:38 -05:00
wanghongzhe a381b70a1c seccomp: Improve performace by optimizing rmb()
According to Kees's suggest, we started with the patch that just replaces
rmb() with smp_rmb() and did a performance test with UnixBench. The
results showed the overhead about 2.53% in rmb() test compared to the
smp_rmb() one, in a x86-64 kernel with CONFIG_SMP enabled running inside a
qemu-kvm vm. The test is a "syscall" testcase in UnixBench, which executes
5 syscalls in a loop during a certain timeout (100 second in our test) and
counts the total number of executions of this 5-syscall sequence. We set
a seccomp filter with all allow rule for all used syscalls in this test
(which will go bitmap path) to make sure the rmb() will be executed. The
details for the test:

with rmb():
/txm # ./syscall_allow_min 100
COUNT|35861159|1|lps
/txm # ./syscall_allow_min 100
COUNT|35545501|1|lps
/txm # ./syscall_allow_min 100
COUNT|35664495|1|lps

with smp_rmb():
/txm # ./syscall_allow_min 100
COUNT|36552771|1|lps
/txm # ./syscall_allow_min 100
COUNT|36491247|1|lps
/txm # ./syscall_allow_min 100
COUNT|36504746|1|lps

For a x86-64 kernel with CONFIG_SMP enabled, the smp_rmb() is just a
compiler barrier() which have no impact in runtime, while rmb() is a
lfence which will prevent all memory access operations (not just load
according the recently claim by Intel) behind itself. We can also figure
it out in disassembly:

with rmb():
0000000000001430 <__seccomp_filter>:
    1430:   41 57                   push   %r15
    1432:   41 56                   push   %r14
    1434:   41 55                   push   %r13
    1436:   41 54                   push   %r12
    1438:   55                      push   %rbp
    1439:   53                      push   %rbx
    143a:   48 81 ec 90 00 00 00    sub    $0x90,%rsp
    1441:   89 7c 24 10             mov    %edi,0x10(%rsp)
    1445:   89 54 24 14             mov    %edx,0x14(%rsp)
    1449:   65 48 8b 04 25 28 00    mov    %gs:0x28,%rax
    1450:   00 00
    1452:   48 89 84 24 88 00 00    mov    %rax,0x88(%rsp)
    1459:   00
    145a:   31 c0                   xor    %eax,%eax
*   145c:   0f ae e8                lfence
    145f:   48 85 f6                test   %rsi,%rsi
    1462:   49 89 f4                mov    %rsi,%r12
    1465:   0f 84 42 03 00 00       je     17ad <__seccomp_filter+0x37d>
    146b:   65 48 8b 04 25 00 00    mov    %gs:0x0,%rax
    1472:   00 00
    1474:   48 8b 98 80 07 00 00    mov    0x780(%rax),%rbx
    147b:   48 85 db                test   %rbx,%rbx

with smp_rmb();
0000000000001430 <__seccomp_filter>:
    1430:   41 57                   push   %r15
    1432:   41 56                   push   %r14
    1434:   41 55                   push   %r13
    1436:   41 54                   push   %r12
    1438:   55                      push   %rbp
    1439:   53                      push   %rbx
    143a:   48 81 ec 90 00 00 00    sub    $0x90,%rsp
    1441:   89 7c 24 10             mov    %edi,0x10(%rsp)
    1445:   89 54 24 14             mov    %edx,0x14(%rsp)
    1449:   65 48 8b 04 25 28 00    mov    %gs:0x28,%rax
    1450:   00 00
    1452:   48 89 84 24 88 00 00    mov    %rax,0x88(%rsp)
    1459:   00
    145a:   31 c0                   xor    %eax,%eax
    145c:   48 85 f6                test   %rsi,%rsi
    145f:   49 89 f4                mov    %rsi,%r12
    1462:   0f 84 42 03 00 00       je     17aa <__seccomp_filter+0x37a>
    1468:   65 48 8b 04 25 00 00    mov    %gs:0x0,%rax
    146f:   00 00
    1471:   48 8b 98 80 07 00 00    mov    0x780(%rax),%rbx
    1478:   48 85 db                test   %rbx,%rbx

Signed-off-by: wanghongzhe <wanghongzhe@huawei.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/1612496049-32507-1-git-send-email-wanghongzhe@huawei.com
2021-02-10 12:40:11 -08:00
Linus Torvalds 6016bf19b3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:
 "Another pile of networing fixes:

   1) ath9k build error fix from Arnd Bergmann

   2) dma memory leak fix in mediatec driver from Lorenzo Bianconi.

   3) bpf int3 kprobe fix from Alexei Starovoitov.

   4) bpf stackmap integer overflow fix from Bui Quang Minh.

   5) Add usb device ids for Cinterion MV31 to qmi_qwwan driver, from
      Christoph Schemmel.

   6) Don't update deleted entry in xt_recent netfilter module, from
      Jazsef Kadlecsik.

   7) Use after free in nftables, fix from Pablo Neira Ayuso.

   8) Header checksum fix in flowtable from Sven Auhagen.

   9) Validate user controlled length in qrtr code, from Sabyrzhan
      Tasbolatov.

  10) Fix race in xen/netback, from Juergen Gross,

  11) New device ID in cxgb4, from Raju Rangoju.

  12) Fix ring locking in rxrpc release call, from David Howells.

  13) Don't return LAPB error codes from x25_open(), from Xie He.

  14) Missing error returns in gsi_channel_setup() from Alex Elder.

  15) Get skb_copy_and_csum_datagram working properly with odd segment
      sizes, from Willem de Bruijn.

  16) Missing RFS/RSS table init in enetc driver, from Vladimir Oltean.

  17) Do teardown on probe failure in DSA, from Vladimir Oltean.

  18) Fix compilation failures of txtimestamp selftest, from Vadim
      Fedorenko.

  19) Limit rx per-napi gro queue size to fix latency regression, from
      Eric Dumazet.

  20) dpaa_eth xdp fixes from Camelia Groza.

  21) Missing txq mode update when switching CBS off, in stmmac driver,
      from Mohammad Athari Bin Ismail.

  22) Failover pending logic fix in ibmvnic driver, from Sukadev
      Bhattiprolu.

  23) Null deref fix in vmw_vsock, from Norbert Slusarek.

  24) Missing verdict update in xdp paths of ena driver, from Shay
      Agroskin.

  25) seq_file iteration fix in sctp from Neil Brown.

  26) bpf 32-bit src register truncation fix on div/mod, from Daniel
      Borkmann.

  27) Fix jmp32 pruning in bpf verifier, from Daniel Borkmann.

  28) Fix locking in vsock_shutdown(), from Stefano Garzarella.

  29) Various missing index bound checks in hns3 driver, from Yufeng Mo.

  30) Flush ports on .phylink_mac_link_down() in dsa felix driver, from
      Vladimir Oltean.

  31) Don't mix up stp and mrp port states in bridge layer, from Horatiu
      Vultur.

  32) Fix locking during netif_tx_disable(), from Edwin Peer"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (45 commits)
  bpf: Fix 32 bit src register truncation on div/mod
  bpf: Fix verifier jmp32 pruning decision logic
  bpf: Fix verifier jsgt branch analysis on max bound
  vsock: fix locking in vsock_shutdown()
  net: hns3: add a check for index in hclge_get_rss_key()
  net: hns3: add a check for tqp_index in hclge_get_ring_chain_from_mbx()
  net: hns3: add a check for queue_id in hclge_reset_vf_queue()
  net: dsa: felix: implement port flushing on .phylink_mac_link_down
  switchdev: mrp: Remove SWITCHDEV_ATTR_ID_MRP_PORT_STAT
  bridge: mrp: Fix the usage of br_mrp_port_switchdev_set_state
  net: watchdog: hold device global xmit lock during tx disable
  netfilter: nftables: relax check for stateful expressions in set definition
  netfilter: conntrack: skip identical origin tuple in same zone only
  vsock/virtio: update credit only if socket is not closed
  net: fix iteration for sctp transport seq_files
  net: ena: Update XDP verdict upon failure
  net/vmw_vsock: improve locking in vsock_connect_timeout()
  net/vmw_vsock: fix NULL pointer dereference
  ibmvnic: Clear failover_pending if unable to schedule
  net: stmmac: set TxQ mode back to DCB after disabling CBS
  ...
2021-02-10 11:33:39 -08:00
Andrei Matei 01f810ace9 bpf: Allow variable-offset stack access
Before this patch, variable offset access to the stack was dissalowed
for regular instructions, but was allowed for "indirect" accesses (i.e.
helpers). This patch removes the restriction, allowing reading and
writing to the stack through stack pointers with variable offsets. This
makes stack-allocated buffers more usable in programs, and brings stack
pointers closer to other types of pointers.

The motivation is being able to use stack-allocated buffers for data
manipulation. When the stack size limit is sufficient, allocating
buffers on the stack is simpler than per-cpu arrays, or other
alternatives.

In unpriviledged programs, variable-offset reads and writes are
disallowed (they were already disallowed for the indirect access case)
because the speculative execution checking code doesn't support them.
Additionally, when writing through a variable-offset stack pointer, if
any pointers are in the accessible range, there's possilibities of later
leaking pointers because the write cannot be tracked precisely.

Writes with variable offset mark the whole range as initialized, even
though we don't know which stack slots are actually written. This is in
order to not reject future reads to these slots. Note that this doesn't
affect writes done through helpers; like before, helpers need the whole
stack range to be initialized to begin with.
All the stack slots are in range are considered scalars after the write;
variable-offset register spills are not tracked.

For reads, all the stack slots in the variable range needs to be
initialized (but see above about what writes do), otherwise the read is
rejected. All register spilled in stack slots that might be read are
marked as having been read, however reads through such pointers don't do
register filling; the target register will always be either a scalar or
a constant zero.

Signed-off-by: Andrei Matei <andreimatei1@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210207011027.676572-2-andreimatei1@gmail.com
2021-02-10 10:44:19 -08:00
Dan Carpenter 1e80d9cb57 module: potential uninitialized return in module_kallsyms_on_each_symbol()
Smatch complains that:

	kernel/module.c:4472 module_kallsyms_on_each_symbol()
        error: uninitialized symbol 'ret'.

This warning looks like it could be correct if the &modules list is
empty.

Fixes: 013c1667cf ("kallsyms: refactor {,module_}kallsyms_on_each_symbol")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-10 16:57:04 +01:00
Sebastian Andrzej Siewior 0f319d49a4 locking/mutex: Kill mutex_trylock_recursive()
There are not users of mutex_trylock_recursive() in tree as of
v5.11-rc7.

Remove it.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210210085248.219210-2-bigeasy@linutronix.de
2021-02-10 14:44:40 +01:00
Peter Zijlstra c8cc7e8531 lockdep: Noinstr annotate warn_bogus_irq_restore()
vmlinux.o: warning: objtool: lock_is_held_type()+0x107: call to warn_bogus_irq_restore() leaves .noinstr.text section

As per the general rule that WARNs are allowed to violate noinstr to
get out, annotate it away.

Fixes: 997acaf6b4 ("lockdep: report broken irq restoration")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lkml.kernel.org/r/YCKyYg53mMp4E7YI@hirez.programming.kicks-ass.net
2021-02-10 14:44:39 +01:00
Muchun Song 8a8109f303 printk: fix deadlock when kernel panic
printk_safe_flush_on_panic() caused the following deadlock on our
server:

CPU0:                                         CPU1:
panic                                         rcu_dump_cpu_stacks
  kdump_nmi_shootdown_cpus                      nmi_trigger_cpumask_backtrace
    register_nmi_handler(crash_nmi_callback)      printk_safe_flush
                                                    __printk_safe_flush
                                                      raw_spin_lock_irqsave(&read_lock)
    // send NMI to other processors
    apic_send_IPI_allbutself(NMI_VECTOR)
                                                        // NMI interrupt, dead loop
                                                        crash_nmi_callback
  printk_safe_flush_on_panic
    printk_safe_flush
      __printk_safe_flush
        // deadlock
        raw_spin_lock_irqsave(&read_lock)

DEADLOCK: read_lock is taken on CPU1 and will never get released.

It happens when panic() stops a CPU by NMI while it has been in
the middle of printk_safe_flush().

Handle the lock the same way as logbuf_lock. The printk_safe buffers
are flushed only when both locks can be safely taken. It can avoid
the deadlock _in this particular case_ at expense of losing contents
of printk_safe buffers.

Note: It would actually be safe to re-init the locks when all CPUs were
      stopped by NMI. But it would require passing this information
      from arch-specific code. It is not worth the complexity.
      Especially because logbuf_lock and printk_safe buffers have been
      obsoleted by the lockless ring buffer.

Fixes: cf9b1106c8 ("printk/nmi: flush NMI messages on the system panic")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: <stable@vger.kernel.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210210034823.64867-1-songmuchun@bytedance.com
2021-02-10 13:57:06 +01:00
Daniel Borkmann e88b2c6e5a bpf: Fix 32 bit src register truncation on div/mod
While reviewing a different fix, John and I noticed an oddity in one of the
BPF program dumps that stood out, for example:

  # bpftool p d x i 13
   0: (b7) r0 = 808464450
   1: (b4) w4 = 808464432
   2: (bc) w0 = w0
   3: (15) if r0 == 0x0 goto pc+1
   4: (9c) w4 %= w0
  [...]

In line 2 we noticed that the mov32 would 32 bit truncate the original src
register for the div/mod operation. While for the two operations the dst
register is typically marked unknown e.g. from adjust_scalar_min_max_vals()
the src register is not, and thus verifier keeps tracking original bounds,
simplified:

  0: R1=ctx(id=0,off=0,imm=0) R10=fp0
  0: (b7) r0 = -1
  1: R0_w=invP-1 R1=ctx(id=0,off=0,imm=0) R10=fp0
  1: (b7) r1 = -1
  2: R0_w=invP-1 R1_w=invP-1 R10=fp0
  2: (3c) w0 /= w1
  3: R0_w=invP(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R1_w=invP-1 R10=fp0
  3: (77) r1 >>= 32
  4: R0_w=invP(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R1_w=invP4294967295 R10=fp0
  4: (bf) r0 = r1
  5: R0_w=invP4294967295 R1_w=invP4294967295 R10=fp0
  5: (95) exit
  processed 6 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0

Runtime result of r0 at exit is 0 instead of expected -1. Remove the
verifier mov32 src rewrite in div/mod and replace it with a jmp32 test
instead. After the fix, we result in the following code generation when
having dividend r1 and divisor r6:

  div, 64 bit:                             div, 32 bit:

   0: (b7) r6 = 8                           0: (b7) r6 = 8
   1: (b7) r1 = 8                           1: (b7) r1 = 8
   2: (55) if r6 != 0x0 goto pc+2           2: (56) if w6 != 0x0 goto pc+2
   3: (ac) w1 ^= w1                         3: (ac) w1 ^= w1
   4: (05) goto pc+1                        4: (05) goto pc+1
   5: (3f) r1 /= r6                         5: (3c) w1 /= w6
   6: (b7) r0 = 0                           6: (b7) r0 = 0
   7: (95) exit                             7: (95) exit

  mod, 64 bit:                             mod, 32 bit:

   0: (b7) r6 = 8                           0: (b7) r6 = 8
   1: (b7) r1 = 8                           1: (b7) r1 = 8
   2: (15) if r6 == 0x0 goto pc+1           2: (16) if w6 == 0x0 goto pc+1
   3: (9f) r1 %= r6                         3: (9c) w1 %= w6
   4: (b7) r0 = 0                           4: (b7) r0 = 0
   5: (95) exit                             5: (95) exit

x86 in particular can throw a 'divide error' exception for div
instruction not only for divisor being zero, but also for the case
when the quotient is too large for the designated register. For the
edx:eax and rdx:rax dividend pair it is not an issue in x86 BPF JIT
since we always zero edx (rdx). Hence really the only protection
needed is against divisor being zero.

Fixes: 68fda450a7 ("bpf: fix 32-bit divide by zero")
Co-developed-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-02-10 01:32:40 +01:00
Daniel Borkmann fd675184fc bpf: Fix verifier jmp32 pruning decision logic
Anatoly has been fuzzing with kBdysch harness and reported a hang in
one of the outcomes:

  func#0 @0
  0: R1=ctx(id=0,off=0,imm=0) R10=fp0
  0: (b7) r0 = 808464450
  1: R0_w=invP808464450 R1=ctx(id=0,off=0,imm=0) R10=fp0
  1: (b4) w4 = 808464432
  2: R0_w=invP808464450 R1=ctx(id=0,off=0,imm=0) R4_w=invP808464432 R10=fp0
  2: (9c) w4 %= w0
  3: R0_w=invP808464450 R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R10=fp0
  3: (66) if w4 s> 0x30303030 goto pc+0
   R0_w=invP808464450 R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff),s32_max_value=808464432) R10=fp0
  4: R0_w=invP808464450 R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff),s32_max_value=808464432) R10=fp0
  4: (7f) r0 >>= r0
  5: R0_w=invP(id=0) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff),s32_max_value=808464432) R10=fp0
  5: (9c) w4 %= w0
  6: R0_w=invP(id=0) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  6: (66) if w0 s> 0x3030 goto pc+0
   R0_w=invP(id=0,s32_max_value=12336) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  7: R0=invP(id=0,s32_max_value=12336) R1=ctx(id=0,off=0,imm=0) R4=invP(id=0) R10=fp0
  7: (d6) if w0 s<= 0x303030 goto pc+1
  9: R0=invP(id=0,s32_max_value=12336) R1=ctx(id=0,off=0,imm=0) R4=invP(id=0) R10=fp0
  9: (95) exit
  propagating r0

  from 6 to 7: safe
  4: R0_w=invP808464450 R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0,umin_value=808464433,umax_value=2147483647,var_off=(0x0; 0x7fffffff)) R10=fp0
  4: (7f) r0 >>= r0
  5: R0_w=invP(id=0) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0,umin_value=808464433,umax_value=2147483647,var_off=(0x0; 0x7fffffff)) R10=fp0
  5: (9c) w4 %= w0
  6: R0_w=invP(id=0) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  6: (66) if w0 s> 0x3030 goto pc+0
   R0_w=invP(id=0,s32_max_value=12336) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  propagating r0
  7: safe
  propagating r0

  from 6 to 7: safe
  processed 15 insns (limit 1000000) max_states_per_insn 0 total_states 1 peak_states 1 mark_read 1

The underlying program was xlated as follows:

  # bpftool p d x i 10
   0: (b7) r0 = 808464450
   1: (b4) w4 = 808464432
   2: (bc) w0 = w0
   3: (15) if r0 == 0x0 goto pc+1
   4: (9c) w4 %= w0
   5: (66) if w4 s> 0x30303030 goto pc+0
   6: (7f) r0 >>= r0
   7: (bc) w0 = w0
   8: (15) if r0 == 0x0 goto pc+1
   9: (9c) w4 %= w0
  10: (66) if w0 s> 0x3030 goto pc+0
  11: (d6) if w0 s<= 0x303030 goto pc+1
  12: (05) goto pc-1
  13: (95) exit

The verifier rewrote original instructions it recognized as dead code with
'goto pc-1', but reality differs from verifier simulation in that we are
actually able to trigger a hang due to hitting the 'goto pc-1' instructions.

Taking a closer look at the verifier analysis, the reason is that it misjudges
its pruning decision at the first 'from 6 to 7: safe' occasion. What happens
is that while both old/cur registers are marked as precise, they get misjudged
for the jmp32 case as range_within() yields true, meaning that the prior
verification path with a wider register bound could be verified successfully
and therefore the current path with a narrower register bound is deemed safe
as well whereas in reality it's not. R0 old/cur path's bounds compare as
follows:

  old: smin_value=0x8000000000000000,smax_value=0x7fffffffffffffff,umin_value=0x0,umax_value=0xffffffffffffffff,var_off=(0x0; 0xffffffffffffffff)
  cur: smin_value=0x8000000000000000,smax_value=0x7fffffff7fffffff,umin_value=0x0,umax_value=0xffffffff7fffffff,var_off=(0x0; 0xffffffff7fffffff)

  old: s32_min_value=0x80000000,s32_max_value=0x00003030,u32_min_value=0x00000000,u32_max_value=0xffffffff
  cur: s32_min_value=0x00003031,s32_max_value=0x7fffffff,u32_min_value=0x00003031,u32_max_value=0x7fffffff

The 64 bit bounds generally look okay and while the information that got
propagated from 32 to 64 bit looks correct as well, it's not precise enough
for judging a conditional jmp32. Given the latter only operates on subregisters
we also need to take these into account as well for a range_within() probe
in order to be able to prune paths. Extending the range_within() constraint
to both bounds will be able to tell us that the old signed 32 bit bounds are
not wider than the cur signed 32 bit bounds.

With the fix in place, the program will now verify the 'goto' branch case as
it should have been:

  [...]
  6: R0_w=invP(id=0) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  6: (66) if w0 s> 0x3030 goto pc+0
   R0_w=invP(id=0,s32_max_value=12336) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  7: R0=invP(id=0,s32_max_value=12336) R1=ctx(id=0,off=0,imm=0) R4=invP(id=0) R10=fp0
  7: (d6) if w0 s<= 0x303030 goto pc+1
  9: R0=invP(id=0,s32_max_value=12336) R1=ctx(id=0,off=0,imm=0) R4=invP(id=0) R10=fp0
  9: (95) exit

  7: R0_w=invP(id=0,smax_value=9223372034707292159,umax_value=18446744071562067967,var_off=(0x0; 0xffffffff7fffffff),s32_min_value=12337,u32_min_value=12337,u32_max_value=2147483647) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  7: (d6) if w0 s<= 0x303030 goto pc+1
   R0_w=invP(id=0,smax_value=9223372034707292159,umax_value=18446744071562067967,var_off=(0x0; 0xffffffff7fffffff),s32_min_value=3158065,u32_min_value=3158065,u32_max_value=2147483647) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  8: R0_w=invP(id=0,smax_value=9223372034707292159,umax_value=18446744071562067967,var_off=(0x0; 0xffffffff7fffffff),s32_min_value=3158065,u32_min_value=3158065,u32_max_value=2147483647) R1=ctx(id=0,off=0,imm=0) R4_w=invP(id=0) R10=fp0
  8: (30) r0 = *(u8 *)skb[808464432]
  BPF_LD_[ABS|IND] uses reserved fields
  processed 11 insns (limit 1000000) max_states_per_insn 1 total_states 1 peak_states 1 mark_read 1

The bug is quite subtle in the sense that when verifier would determine that
a given branch is dead code, it would (here: wrongly) remove these instructions
from the program and hard-wire the taken branch for privileged programs instead
of the 'goto pc-1' rewrites which will cause hard to debug problems.

Fixes: 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-02-10 01:31:46 +01:00
Daniel Borkmann ee114dd64c bpf: Fix verifier jsgt branch analysis on max bound
Fix incorrect is_branch{32,64}_taken() analysis for the jsgt case. The return
code for both will tell the caller whether a given conditional jump is taken
or not, e.g. 1 means branch will be taken [for the involved registers] and the
goto target will be executed, 0 means branch will not be taken and instead we
fall-through to the next insn, and last but not least a -1 denotes that it is
not known at verification time whether a branch will be taken or not. Now while
the jsgt has the branch-taken case correct with reg->s32_min_value > sval, the
branch-not-taken case is off-by-one when testing for reg->s32_max_value < sval
since the branch will also be taken for reg->s32_max_value == sval. The jgt
branch analysis, for example, gets this right.

Fixes: 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Fixes: 4f7b3e8258 ("bpf: improve verifier branch analysis")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-02-10 01:31:45 +01:00
Tom Zanussi 8b5ab6bd0b tracing: Add a backward-compatibility check for synthetic event creation
The synthetic event parsing rework now requires semicolons between
synthetic event fields.  That requirement breaks existing users who
might already have used the old synthetic event command format, so
this adds an inner loop that can parse more than one field, if
present, between semicolons.  For each field, parse_synth_field()
checks in which version that field was introduced, using
check_field_version().  The caller, __create_synth_event() can then use
that version information to determine whether or not to enforce the
requirement on the command as a whole.

In the future, if/when new features are added, the requirement will be
that any field/string containing the new feature must use semicolons,
and the check_field_version() check can then check for those and
enforce it.  Using a version number allows this scheme to be extended
if necessary.

Link: https://lkml.kernel.org/r/74fcc500d561b40ce91c5ee94818c70c6b0c9330.1612208610.git.zanussi@kernel.org

[ zanussi: added check_field_version() comment from rostedt@goodmis.org ]
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09 12:52:15 -05:00
Tom Zanussi 8d3e816523 tracing: Update synth command errors
Since array types are handled differently, errors referencing them
also need to be handled differently.  Add and use a new
INVALID_ARRAY_SPEC error.  Also add INVALID_CMD and INVALID_DYN_CMD to
catch and display the correct form for badly-formed commands, which
can also be used in place of CMD_INCOMPLETE, which is removed, and
remove CMD_TOO_LONG, since it's no longer used.

Link: https://lkml.kernel.org/r/b9dd434dc6458dcff11adc6ed616fe93a8794770.1612208610.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09 12:52:15 -05:00
Tom Zanussi c9e759b1e8 tracing: Rework synthetic event command parsing
Now that command parsing has been delegated to the create functions
and we're no longer constrained by argv_split(), we can modify the
synthetic event command parser to better match the higher-level
structure of the synthetic event commands, which is basically an event
name followed by a set of semicolon-separated fields.

Since we're also now passed the raw command, we can also save it
directly and can get rid of save_cmdstr().

Link: https://lkml.kernel.org/r/cb9e2be92d992ce59f2b4f132264a5d467f3933f.1612208610.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09 12:52:15 -05:00
Masami Hiramatsu d262271d04 tracing/dynevent: Delegate parsing to create function
Delegate command parsing to each create function so that the
command syntax can be customized.

This requires changes to the kprobe/uprobe/synthetic event handling,
which are also included here.

Link: https://lkml.kernel.org/r/e488726f49cbdbc01568618f8680584306c4c79f.1612208610.git.zanussi@kernel.org

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ zanussi@kernel.org: added synthetic event modifications ]
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09 12:52:15 -05:00
Masami Hiramatsu 33b1d14668 kprobes: Warn if the kprobe is reregistered
Warn if the kprobe is reregistered, since there must be
a software bug (actively used resource must not be re-registered)
and caller must be fixed.

Link: https://lkml.kernel.org/r/161236436734.194052.4058506306336814476.stgit@devnote2

Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@linux.ibm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09 12:44:32 -05:00
Steven Rostedt (VMware) 7211f0a257 tracepoints: Code clean up
Restructure the code a bit to make it simpler, fix some formatting problems
and add READ_ONCE/WRITE_ONCE to make sure there's no compiler load/store
tearing to the variables that can be accessed across CPUs.

Started with Mathieu Desnoyers's patch:

  Link: https://lore.kernel.org/lkml/20210203175741.20665-1-mathieu.desnoyers@efficios.com/

And will keep his signature, but I will take the responsibility of this
being correct, and keep the authorship.

Link: https://lkml.kernel.org/r/20210204143004.61126582@gandalf.local.home

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09 12:27:29 -05:00
Christoph Hellwig 81d88ce550 dma-mapping: remove the {alloc,free}_noncoherent methods
It turns out allowing non-contigous allocations here was a rather bad
idea, as we'll now need to define ways to get the pages for mmaping
or dma_buf sharing.  Revert this change and stick to the original
concept.  A different API for the use case of non-contigous allocations
will be added back later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Tested-by: Ricardo Ribalda <ribalda@chromium.org>:wq
2021-02-09 18:01:38 +01:00
Saravana Kannan ed1054a02a irqdomain: Mark fwnodes when their irqdomain is added/removed
This allows fw_devlink to recognize irqdomain drivers that don't use the
device-driver model to initialize the device. fw_devlink will use this
information to make sure consumers of such irqdomain aren't indefinitely
blocked from probing, waiting for the irqdomain device to appear and
bind to a driver.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210205222644.2357303-7-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-09 14:31:06 +01:00
Linus Torvalds e0756cfc7d tracing: Fix output of top level event "enable" file
When writing a tool for enabling events in the tracing system,
 an anomaly was discovered. The top level event "enable" file would
 never show "1" when all events were enabled. The system and event
 "enable" files worked as expected. The reason was because the top
 level event "enable" file included the "ftrace" tracer events,
 which are not controlled by the "enable" file and would cause the
 output to be wrong. This appears to have been a bug since it was created.
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Merge tag 'trace-v5.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Fix output of top level event tracing 'enable' file.

  When writing a tool for enabling events in the tracing system, an
  anomaly was discovered. The top level event 'enable' file would never
  show '1' when all events were enabled.

  The system and event 'enable' files worked as expected.

  The reason was because the top level event 'enable' file included the
  'ftrace' tracer events, which are not controlled by the 'enable' file
  and would cause the output to be wrong. This appears to have been a
  bug since it was created"

* tag 'trace-v5.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Do not count ftrace events in top level enable output
2021-02-08 11:32:39 -08:00
Sumit Garg 93f7a6d818 kdb: Make memory allocations more robust
Currently kdb uses in_interrupt() to determine whether its library
code has been called from the kgdb trap handler or from a saner calling
context such as driver init. This approach is broken because
in_interrupt() alone isn't able to determine kgdb trap handler entry from
normal task context. This can happen during normal use of basic features
such as breakpoints and can also be trivially reproduced using:
echo g > /proc/sysrq-trigger

We can improve this by adding check for in_dbg_master() instead which
explicitly determines if we are running in debugger context.

Cc: stable@vger.kernel.org
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/1611313556-4004-1-git-send-email-sumit.garg@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2021-02-08 13:42:50 +00:00
Christoph Hellwig 367948220f module: remove EXPORT_UNUSED_SYMBOL*
EXPORT_UNUSED_SYMBOL* is not actually used anywhere.  Remove the
unused functionality as we generally just remove unused code anyway.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:28:07 +01:00
Christoph Hellwig f1c3d73e97 module: remove EXPORT_SYMBOL_GPL_FUTURE
As far as I can tell this has never been used at all, and certainly
not any time recently.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:28:02 +01:00
Christoph Hellwig 00cc2c1cd3 module: move struct symsearch to module.c
struct symsearch is only used inside of module.h, so move the definition
out of module.h.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:27:43 +01:00
Christoph Hellwig 0b96615cdc module: pass struct find_symbol_args to find_symbol
Simplify the calling convention by passing the find_symbol_args structure
to find_symbol instead of initializing it inside the function.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:25:19 +01:00
Christoph Hellwig 71e4b309dc module: merge each_symbol_section into find_symbol
each_symbol_section is only called by find_symbol, so merge the two
functions.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:25:07 +01:00
Christoph Hellwig a7c38f2cd3 module: remove each_symbol_in_section
each_symbol_in_section just contains a trivial loop over its arguments.
Just open code the loop in the two callers.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:24:54 +01:00
Christoph Hellwig 922f2a7c82 module: mark module_mutex static
Except for two lockdep asserts module_mutex is only used in module.c.
Remove the two asserts given that the functions they are in are not
exported and just called from the module code, and mark module_mutex
static.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:24:26 +01:00
Christoph Hellwig 3e3552056a kallsyms: only build {,module_}kallsyms_on_each_symbol when required
kallsyms_on_each_symbol and module_kallsyms_on_each_symbol are only used
by the livepatching code, so don't build them if livepatching is not
enabled.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:24:04 +01:00
Christoph Hellwig 013c1667cf kallsyms: refactor {,module_}kallsyms_on_each_symbol
Require an explicit call to module_kallsyms_on_each_symbol to look
for symbols in modules instead of the call from kallsyms_on_each_symbol,
and acquire module_mutex inside of module_kallsyms_on_each_symbol instead
of leaving that up to the caller.  Note that this slightly changes the
behavior for the livepatch code in that the symbols from vmlinux are not
iterated anymore if objname is set, but that actually is the desired
behavior in this case.

Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:22:08 +01:00
Christoph Hellwig a006050575 module: use RCU to synchronize find_module
Allow for a RCU-sched critical section around find_module, following
the lower level find_module_all helper, and switch the two callers
outside of module.c to use such a RCU-sched critical section instead
of module_mutex.

Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:21:40 +01:00
Christoph Hellwig 089049f6c9 module: unexport find_module and module_mutex
find_module is not used by modular code any more, and random driver code
has no business calling it to start with.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:21:16 +01:00
Linus Torvalds ff92acb220 dma-mapping fixes for 5.11:
- fix a 32 vs 64-bit padding issue in the new benchmark code
    (Barry Song)
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Merge tag 'dma-mapping-5.11-2' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fix from Christoph Hellwig:
 "Fix a 32 vs 64-bit padding issue in the new benchmark code (Barry
  Song)"

* tag 'dma-mapping-5.11-2' of git://git.infradead.org/users/hch/dma-mapping:
  dma-mapping: benchmark: use u8 for reserved field in uAPI structure
2021-02-07 10:40:48 -08:00
Linus Torvalds fc6c0ae53a - Prevent device managed IRQ allocation helpers from returning IRQ 0.
- A fix for MSI activation of PCI endpoints with multiple MSIs.
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Merge tag 'irq_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Borislav Petkov:

 - Prevent device managed IRQ allocation helpers from returning IRQ 0

 - A fix for MSI activation of PCI endpoints with multiple MSIs

* tag 'irq_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Prevent [devm_]irq_alloc_desc from returning irq 0
  genirq/msi: Activate Multi-MSI early when MSI_FLAG_ACTIVATE_EARLY is set
2021-02-07 10:25:01 -08:00
Linus Torvalds c6792d44d8 - For syscall user dispatch, separate ptctl operation from syscall
redirection range specification before the API has been made official in 5.11.
 
 - Ensure tasks using the generic syscall code do trap after returning
 from a syscall when single-stepping is requested.
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Merge tag 'core_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull syscall entry fixes from Borislav Petkov:

 - For syscall user dispatch, separate prctl operation from syscall
   redirection range specification before the API has been made official
   in 5.11.

 - Ensure tasks using the generic syscall code do trap after returning
   from a syscall when single-stepping is requested.

* tag 'core_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  entry: Use different define for selector variable in SUD
  entry: Ensure trap after single-step on system call return
2021-02-07 10:16:24 -08:00
Linus Torvalds 814daadbf0 - Use a freezable workqueue for RTC sync because the sync can happen at any time
and trigger suspend assertion checks in the i2c subsystem.
 
 - Correct a previous RTC validation change to check only bit 6 in register D
 because some Intel machines use bits 0-5.
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Merge tag 'timers_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Borislav Petkov:
 "Two more timers-related fixes for v5.11:

   - Use a freezable workqueue for RTC sync because the sync can happen
     at any time and trigger suspend assertion checks in the i2c
     subsystem.

   - Correct a previous RTC validation change to check only bit 6 in
     register D because some Intel machines use bits 0-5"

* tag 'timers_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ntp: Use freezable workqueue for RTC synchronization
  rtc: mc146818: Dont test for bit 0-5 in Register D
2021-02-07 09:55:26 -08:00
Gabriel Krisman Bertazi 36a6c843fd entry: Use different define for selector variable in SUD
Michael Kerrisk suggested that, from an API perspective, it is a bad
idea to share the PR_SYS_DISPATCH_ defines between the prctl operation
and the selector variable.

Therefore, define two new constants to be used by SUD's selector variable
and update the corresponding documentation and test cases.

While this changes the API syscall user dispatch has never been part of a
Linux release, it will show up for the first time in 5.11.

Suggested-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210205184321.2062251-1-krisman@collabora.com
2021-02-06 00:21:42 +01:00
Gabriel Krisman Bertazi 6342adcaa6 entry: Ensure trap after single-step on system call return
Commit 2991552447 ("entry: Drop usage of TIF flags in the generic syscall
code") introduced a bug on architectures using the generic syscall entry
code, in which processes stopped by PTRACE_SYSCALL do not trap on syscall
return after receiving a TIF_SINGLESTEP.

The reason is that the meaning of TIF_SINGLESTEP flag is overloaded to
cause the trap after a system call is executed, but since the above commit,
the syscall call handler only checks for the SYSCALL_WORK flags on the exit
work.

Split the meaning of TIF_SINGLESTEP such that it only means single-step
mode, and create a new type of SYSCALL_WORK to request a trap immediately
after a syscall in single-step mode.  In the current implementation, the
SYSCALL_WORK flag shadows the TIF_SINGLESTEP flag for simplicity.

Update x86 to flip this bit when a tracer enables single stepping.

Fixes: 2991552447 ("entry: Drop usage of TIF flags in the generic syscall code")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kyle Huey <me@kylehuey.com>
Link: https://lore.kernel.org/r/87h7mtc9pr.fsf_-_@collabora.com
2021-02-06 00:21:42 +01:00
Steven Rostedt (VMware) 2d396cb3b1 tracing: Do not create "enable" or "filter" files for ftrace event subsystem
The ftrace event subsystem is only created for showing the format files of
events created by the ftrace tracers, and are not trace events. The ftrace
subsystem currently has both the "enable" and "filter" files that in other
subsystems are used to enable/disable all events within the subsystem or set
a filter for all the subsystem events.

As ftrace subsystem events do not use enable or filter operations, these
files are useless in the ftrace subsystem. Remove them.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-05 18:04:39 -05:00
Steven Rostedt (VMware) 256cfdd6fd tracing: Do not count ftrace events in top level enable output
The file /sys/kernel/tracing/events/enable is used to enable all events by
echoing in "1", or disabling all events when echoing in "0". To know if all
events are enabled, disabled, or some are enabled but not all of them,
cating the file should show either "1" (all enabled), "0" (all disabled), or
"X" (some enabled but not all of them). This works the same as the "enable"
files in the individule system directories (like tracing/events/sched/enable).

But when all events are enabled, the top level "enable" file shows "X". The
reason is that its checking the "ftrace" events, which are special events
that only exist for their format files. These include the format for the
function tracer events, that are enabled when the function tracer is
enabled, but not by the "enable" file. The check includes these events,
which will always be disabled, and even though all true events are enabled,
the top level "enable" file will show "X" instead of "1".

To fix this, have the check test the event's flags to see if it has the
"IGNORE_ENABLE" flag set, and if so, not test it.

Cc: stable@vger.kernel.org
Fixes: 553552ce17 ("tracing: Combine event filter_active and enable into single flags field")
Reported-by: "Yordan Karadzhov (VMware)" <y.karadz@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-05 15:40:04 -05:00
Johannes Berg 55b6f763d8 init/gcov: allow CONFIG_CONSTRUCTORS on UML to fix module gcov
On ARCH=um, loading a module doesn't result in its constructors getting
called, which breaks module gcov since the debugfs files are never
registered.  On the other hand, in-kernel constructors have already been
called by the dynamic linker, so we can't call them again.

Get out of this conundrum by allowing CONFIG_CONSTRUCTORS to be
selected, but avoiding the in-kernel constructor calls.

Also remove the "if !UML" from GCOV selecting CONSTRUCTORS now, since we
really do want CONSTRUCTORS, just not kernel binary ones.

Link: https://lkml.kernel.org/r/20210120172041.c246a2cac2fb.I1358f584b76f1898373adfed77f4462c8705b736@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-05 11:03:47 -08:00
Alexey Dobriyan 174bcc691f timens: Delete no-op time_ns_init()
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andrei Vagin <avagin@gmail.com>
Link: https://lore.kernel.org/r/20201228215402.GA572900@localhost.localdomain
2021-02-05 19:32:09 +01:00
Alexandre Belloni b5c28ea601 alarmtimer: Update kerneldoc
Update kerneldoc comments to reflect the actual arguments and return values
of the documented functions.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210202013457.3482388-1-alexandre.belloni@bootlin.com
2021-02-05 19:26:41 +01:00
Geert Uytterhoeven 24c242ec7a ntp: Use freezable workqueue for RTC synchronization
The bug fixed by commit e3fab2f3de ("ntp: Fix RTC synchronization on
32-bit platforms") revealed an underlying issue: RTC synchronization may
happen anytime, even while the system is partially suspended.

On systems where the RTC is connected to an I2C bus, the I2C bus controller
may already or still be suspended, triggering a WARNING during suspend or
resume from s2ram:

    WARNING: CPU: 0 PID: 124 at drivers/i2c/i2c-core.h:54 __i2c_transfer+0x634/0x680
    i2c i2c-6: Transfer while suspended
    [...]
    Workqueue: events_power_efficient sync_hw_clock
    [...]
      (__i2c_transfer)
      (i2c_transfer)
      (regmap_i2c_read)
      ...
      (da9063_rtc_set_time)
      (rtc_set_time)
      (sync_hw_clock)
      (process_one_work)

Fix this race condition by using the freezable instead of the normal
power-efficient workqueue.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20210125143039.1051912-1-geert+renesas@glider.be
2021-02-05 18:03:13 +01:00
Peter Zijlstra 7f82e631d2 locking/lockdep: Avoid unmatched unlock
Commit f6f48e1804 ("lockdep: Teach lockdep about "USED" <- "IN-NMI"
inversions") overlooked that print_usage_bug() releases the graph_lock
and called it without the graph lock held.

Fixes: f6f48e1804 ("lockdep: Teach lockdep about "USED" <- "IN-NMI" inversions")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lkml.kernel.org/r/YBfkuyIfB1+VRxXP@hirez.programming.kicks-ass.net
2021-02-05 17:20:15 +01:00
Barry Song 9dc00b25ea dma-mapping: benchmark: pretend DMA is transmitting
In a real dma mapping user case, after dma_map is done, data will be
transmit. Thus, in multi-threaded user scenario, IOMMU contention
should not be that severe. For example, if users enable multiple
threads to send network packets through 1G/10G/100Gbps NIC, usually
the steps will be: map -> transmission -> unmap.  Transmission delay
reduces the contention of IOMMU.

Here a delay is added to simulate the transmission between map and unmap
so that the tested result could be more accurate for TX and simple RX.
A typical TX transmission for NIC would be like: map -> TX -> unmap
since the socket buffers come from OS. Simple RX model eg. disk driver,
is also map -> RX -> unmap, but real RX model in a NIC could be more
complicated considering packets can come spontaneously and many drivers
are using pre-mapped buffers pool. This is in the TBD list.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-02-05 12:48:46 +01:00
Barry Song 9f5f8ec501 dma-mapping: benchmark: use u8 for reserved field in uAPI structure
The original code put five u32 before a u64 expansion[10] array. Five is
odd, this will cause trouble in the extension of the structure by adding
new features. This patch moves to use u8 for reserved field to avoid
future alignment risk.
Meanwhile, it also clears the memory of struct map_benchmark in tools,
otherwise, if users use old version to run on newer kernel, the random
expansion value will cause side effect on newer kernel.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-02-05 12:48:46 +01:00
Yonghong Song 23a2d70c7a bpf: Refactor BPF_PSEUDO_CALL checking as a helper function
There is no functionality change. This refactoring intends
to facilitate next patch change with BPF_PSEUDO_FUNC.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210204234827.1628953-1-yhs@fb.com
2021-02-04 21:51:47 -08:00
KP Singh ba90c2cc02 bpf: Allow usage of BPF ringbuffer in sleepable programs
The BPF ringbuffer map is pre-allocated and the implementation logic
does not rely on disabling preemption or per-cpu data structures. Using
the BPF ringbuffer sleepable LSM and tracing programs does not trigger
any warnings with DEBUG_ATOMIC_SLEEP, DEBUG_PREEMPT,
PROVE_RCU and PROVE_LOCKING and LOCKDEP enabled.

This allows helpers like bpf_copy_from_user and bpf_ima_inode_hash to
write to the BPF ring buffer from sleepable BPF programs.

Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210204193622.3367275-2-kpsingh@kernel.org
2021-02-04 16:35:00 -08:00
Stephen Zhang 0759d80728 kdb: kdb_support: Fix debugging information problem
There are several common patterns.

0:
        kdb_printf("...",...);

which is the normal one.

1:
        kdb_printf("%s: "...,__func__,...)

We could improve '1' to this :

        #define kdb_func_printf(format, args...) \
                kdb_printf("%s: " format, __func__, ## args)

2:
        if(KDB_DEBUG(AR))
                kdb_printf("%s "...,__func__,...);

We could improve '2' to this :
        #define kdb_dbg_printf(mask, format, args...) \
                do { \
                        if (KDB_DEBUG(mask)) \
                                kdb_func_printf(format, ## args); \
                } while (0)

In addition, we changed the format code of size_t to %zu.

Signed-off-by: Stephen Zhang <stephenzhangzsd@gmail.com>
Link: https://lore.kernel.org/r/1612440429-6391-1-git-send-email-stephenzhangzsd@gmail.com
Reviewed-by: Douglas Anderson <dianders@chromium.org>
[daniel.thompson@linaro.org: Minor typo and line length fixes in the
patch description]
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2021-02-04 15:55:04 +00:00
wengjianfeng cbd026e1d8 kernel: debug: fix typo issue
change 'regster' to 'register'.

Signed-off-by: wengjianfeng <wengjianfeng@yulong.com>
Link: https://lore.kernel.org/r/20210203081034.9004-1-samirweng1979@163.com
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2021-02-04 15:26:03 +00:00
Lukas Bulwahn 2da2687b51 kgdb: rectify kernel-doc for kgdb_unregister_io_module()
The command 'find ./kernel/debug/ | xargs ./scripts/kernel-doc -none'
reported a typo in the kernel-doc of kgdb_unregister_io_module().

Rectify the kernel-doc, such that no issues remain for ./kernel/debug/.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20210125144847.21896-1-lukas.bulwahn@gmail.com
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2021-02-04 15:23:25 +00:00
Ben Gardon f3d4b4b1dc sched: Add cond_resched_rwlock
Safely rescheduling while holding a spin lock is essential for keeping
long running kernel operations running smoothly. Add the facility to
cond_resched rwlocks.

CC: Ingo Molnar <mingo@redhat.com>
CC: Will Deacon <will@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Waiman Long <longman@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20210202185734.1680553-9-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-04 05:27:43 -05:00
Bui Quang Minh 6183f4d3a0 bpf: Check for integer overflow when using roundup_pow_of_two()
On 32-bit architecture, roundup_pow_of_two() can return 0 when the argument
has upper most bit set due to resulting 1UL << 32. Add a check for this case.

Fixes: d5a3b1f691 ("bpf: introduce BPF_MAP_TYPE_STACK_TRACE")
Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210127063653.3576-1-minhquangbui99@gmail.com
2021-02-03 21:45:33 +01:00
Linus Torvalds dbc15d24f9 Tracing fixes:
- Initialize tracing-graph-pause at task creation, not start of
    function tracing. Causes the pause counter to be corrupted.
  - Set "pause-on-trace" for latency tracers as that option breaks
    their output (regression).
  - Fix the wrong error return for setting kretprobes on future
    modules (before they are loaded).
  - Fix re-registering the same kretprobe.
  - Add missing value check for added RCU variable reload.
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Merge tag 'trace-v5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Initialize tracing-graph-pause at task creation, not start of
   function tracing, to avoid corrupting the pause counter.

 - Set "pause-on-trace" for latency tracers as that option breaks their
   output (regression).

 - Fix the wrong error return for setting kretprobes on future modules
   (before they are loaded).

 - Fix re-registering the same kretprobe.

 - Add missing value check for added RCU variable reload.

* tag 'trace-v5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracepoint: Fix race between tracing and removing tracepoint
  kretprobe: Avoid re-registration of the same kretprobe earlier
  tracing/kprobe: Fix to support kretprobe events on unloaded modules
  tracing: Use pause-on-trace with the latency tracers
  fgraph: Initialize tracing_graph_pause at task creation
2021-02-03 10:02:00 -08:00
Alexei Starovoitov 548f1191d8 bpf: Unbreak BPF_PROG_TYPE_KPROBE when kprobe is called via do_int3
The commit 0d00449c7a ("x86: Replace ist_enter() with nmi_enter()")
converted do_int3 handler to be "NMI-like".
That made old if (in_nmi()) check abort execution of bpf programs
attached to kprobe when kprobe is firing via int3
(For example when kprobe is placed in the middle of the function).
Remove the check to restore user visible behavior.

Fixes: 0d00449c7a ("x86: Replace ist_enter() with nmi_enter()")
Reported-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/bpf/20210203070636.70926-1-alexei.starovoitov@gmail.com
2021-02-03 15:54:22 +01:00
Brendan Jackman 37086bfdc7 bpf: Propagate stack bounds to registers in atomics w/ BPF_FETCH
When BPF_FETCH is set, atomic instructions load a value from memory
into a register. The current verifier code first checks via
check_mem_access whether we can access the memory, and then checks
via check_reg_arg whether we can write into the register.

For loads, check_reg_arg has the side-effect of marking the
register's value as unkonwn, and check_mem_access has the side effect
of propagating bounds from memory to the register. This currently only
takes effect for stack memory.

Therefore with the current order, bounds information is thrown away,
but by simply reversing the order of check_reg_arg
vs. check_mem_access, we can instead propagate bounds smartly.

A simple test is added with an infinite loop that can only be proved
unreachable if this propagation is present. This is implemented both
with C and directly in test_verifier using assembly.

Suggested-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210202135002.4024825-1-jackmanb@google.com
2021-02-02 18:23:29 -08:00
Jakub Kicinski d1e1355aef Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-02 14:21:31 -08:00
Song Chen 4b9091e1c1 kernel: trace: preemptirq_delay_test: add cpu affinity
The kernel thread executing test can run on any cpu, which might be
different cpu latency tracer is running on, as a result, the
big latency caused by preemptirq delay test can't be detected.

Therefore, the argument cpu_affinity is added to be passed to test,
ensure it's running on the same cpu with latency tracer.

e.g.
cyclictest -p 90 -m -c 0 -i 1000 -a 3
modprobe preemptirq_delay_test test_mode=preempt delay=500 \
burst_size=3 cpu_affinity=3

Link: https://lkml.kernel.org/r/1611797713-20965-1-git-send-email-chensong_2000@189.cn

Signed-off-by: Song Chen <chensong_2000@189.cn>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:07 -05:00
Steven Rostedt (VMware) befe6d9465 tracepoint: Do not fail unregistering a probe due to memory failure
The list of tracepoint callbacks is managed by an array that is protected
by RCU. To update this array, a new array is allocated, the updates are
copied over to the new array, and then the list of functions for the
tracepoint is switched over to the new array. After a completion of an RCU
grace period, the old array is freed.

This process happens for both adding a callback as well as removing one.
But on removing a callback, if the new array fails to be allocated, the
callback is not removed, and may be used after it is freed by the clients
of the tracepoint.

There's really no reason to fail if the allocation for a new array fails
when removing a function. Instead, the function can simply be replaced by a
stub function that could be cleaned up on the next modification of the
array. That is, instead of calling the function registered to the
tracepoint, it would call a stub function in its place.

Link: https://lore.kernel.org/r/20201115055256.65625-1-mmullins@mmlx.us
Link: https://lore.kernel.org/r/20201116175107.02db396d@gandalf.local.home
Link: https://lore.kernel.org/r/20201117211836.54acaef2@oasis.local.home
Link: https://lkml.kernel.org/r/20201118093405.7a6d2290@gandalf.local.home

[ Note, this version does use undefined compiler behavior (assuming that
  a stub function with no parameters or return, can be called by a location
  that thinks it has parameters but still no return value. Static calls
  do the same thing, so this trick is not without precedent.

  There's another solution that uses RCU tricks and is more complex, but
  can be an alternative if this solution becomes an issue.

  Link: https://lore.kernel.org/lkml/20210127170721.58bce7cc@gandalf.local.home/
]

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Cc: netdev <netdev@vger.kernel.org>
Cc: bpf <bpf@vger.kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Florian Weimer <fw@deneb.enyo.de>
Fixes: 97e1c18e8d ("tracing: Kernel Tracepoints")
Reported-by: syzbot+83aa762ef23b6f0d1991@syzkaller.appspotmail.com
Reported-by: syzbot+d29e58bb557324e55e5e@syzkaller.appspotmail.com
Reported-by: Matt Mullins <mmullins@mmlx.us>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tested-by: Matt Mullins <mmullins@mmlx.us>
2021-02-02 17:02:07 -05:00
Tom Rix f2a99ddfd0 tracing: Remove definition of DEBUG in trace_mmiotrace.c
Defining DEBUG should only be done in development.
So remove DEBUG.

Link: https://lkml.kernel.org/r/20210115153348.131791-1-trix@redhat.com

Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:07 -05:00
Bean Huo 557d50e79d tracing: Fix a kernel doc warning
Add description for trace_array_put() parameter.

kernel/trace/trace.c:464: warning: Function parameter or member 'this_tr' not described in 'trace_array_put'

Link: https://lkml.kernel.org/r/20210112111202.23508-1-huobean@gmail.com

Signed-off-by: Bean Huo <beanhuo@micron.com>
[ Merged as one of the original fixes was already fixed by someone else ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:07 -05:00
Bhaskar Chowdhury 39bcdd6a96 tracing: Fix spelling of controlling in uprobes
s/controling/controlling/p

Link: https://lkml.kernel.org/r/20210112045008.29834-1-unixbhaskar@gmail.com

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:07 -05:00
Colin Ian King 28cc65a173 tracing: Fix spelling mistake in Kconfig "infinit" -> "infinite"
There is a spelling mistake in the Kconfig help text. Fix it.

Link: https://lkml.kernel.org/r/20201216114051.12056-1-colin.king@canonical.com

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:07 -05:00
Sebastian Andrzej Siewior fe427886bf tracing: Use in_serving_softirq() to deduct softirq status.
PREEMPT_RT does not report "serving softirq" because the tracing core
looks at the preemption counter while PREEMPT_RT does not update it
while processing softirqs in order to remain preemptible. The
information is stored somewhere else.
The in_serving_softirq() macro and the SOFTIRQ_OFFSET define are still
working but not on the preempt-counter.

Use in_serving_softirq() macro which works on PREEMPT_RT. On !PREEMPT_RT
the compiler (gcc-10 / clang-11) is smart enough to optimize the
in_serving_softirq() related read of the preemption counter away.
The only difference I noticed by using in_serving_softirq() on
!PREEMPT_RT is that gcc-10 implemented tracing_gen_ctx_flags() as
reading FLAG, jmp _tracing_gen_ctx_flags(). Without in_serving_softirq()
it inlined _tracing_gen_ctx_flags() into tracing_gen_ctx_flags().

Link: https://lkml.kernel.org/r/20210125194511.3924915-4-bigeasy@linutronix.de

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:06 -05:00
Sebastian Andrzej Siewior 0c02006e6f tracing: Inline tracing_gen_ctx_flags()
Inline tracing_gen_ctx_flags(). This allows to have one ifdef
CONFIG_TRACE_IRQFLAGS_SUPPORT.

This requires to move `trace_flag_type' so tracing_gen_ctx_flags() can
use it.

Link: https://lkml.kernel.org/r/20210125194511.3924915-3-bigeasy@linutronix.de

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20210125140323.6b1ff20c@gandalf.local.home
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:06 -05:00
Sebastian Andrzej Siewior 36590c50b2 tracing: Merge irqflags + preempt counter.
The state of the interrupts (irqflags) and the preemption counter are
both passed down to tracing_generic_entry_update(). Only one bit of
irqflags is actually required: The on/off state. The complete 32bit
of the preemption counter isn't needed. Just whether of the upper bits
(softirq, hardirq and NMI) are set and the preemption depth is needed.

The irqflags and the preemption counter could be evaluated early and the
information stored in an integer `trace_ctx'.
tracing_generic_entry_update() would use the upper bits as the
TRACE_FLAG_* and the lower 8bit as the disabled-preemption depth
(considering that one must be substracted from the counter in one
special cases).

The actual preemption value is not used except for the tracing record.
The `irqflags' variable is mostly used only for the tracing record. An
exception here is for instance wakeup_tracer_call() or
probe_wakeup_sched_switch() which explicilty disable interrupts and use
that `irqflags' to save (and restore) the IRQ state and to record the
state.

Struct trace_event_buffer has also the `pc' and flags' members which can
be replaced with `trace_ctx' since their actual value is not used
outside of trace recording.

This will reduce tracing_generic_entry_update() to simply assign values
to struct trace_entry. The evaluation of the TRACE_FLAG_* bits is moved
to _tracing_gen_ctx_flags() which replaces preempt_count() and
local_save_flags() invocations.

As an example, ftrace_syscall_enter() may invoke:
- trace_buffer_lock_reserve() -> … -> tracing_generic_entry_update()
- event_trigger_unlock_commit()
  -> ftrace_trace_stack() -> … -> tracing_generic_entry_update()
  -> ftrace_trace_userstack() -> … -> tracing_generic_entry_update()

In this case the TRACE_FLAG_* bits were evaluated three times. By using
the `trace_ctx' they are evaluated once and assigned three times.

A build with all tracers enabled on x86-64 with and without the patch:

    text     data      bss      dec      hex    filename
21970669 17084168  7639260 46694097  2c87ed1 vmlinux.old
21970293 17084168  7639260 46693721  2c87d59 vmlinux.new

text shrank by 379 bytes, data remained constant.

Link: https://lkml.kernel.org/r/20210125194511.3924915-2-bigeasy@linutronix.de

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:06 -05:00
Qiujun Huang c6358bacdc ring-buffer: Drop unneeded check in ring_buffer_resize()
Remove the cpumask check, as we has done it at the beginning of
the function.
Also fix a typo. s/also the on the/also on the/

Link: https://lkml.kernel.org/r/20201224144634.3210-1-hqjagain@gmail.com

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:06 -05:00
Qiujun Huang 6689bed36c ring-buffer: Remove cpu_buffer argument from the rb_inc_page()
The cpu_buffer argument is not used inside the rb_inc_page() after
commit 3adc54fa82 ("ring-buffer: make the buffer a true circular link
list").
And cpu_buffer argument is not used inside the two functions too,
rb_is_head_page/rb_set_list_to_head.

Link: https://lkml.kernel.org/r/20201225140356.23008-1-hqjagain@gmail.com

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:06 -05:00
Qiujun Huang 18d14ebdbd tracing: Remove get/put_cpu() from function_trace_init
Since commit b6f11df26f ("trace: Call tracing_reset_online_cpus before
tracer->init()"), get/put_cpu() are not needed anymore.
We can use raw_smp_processor_id() instead.

Link: https://lkml.kernel.org/r/20201230140521.31920-1-hqjagain@gmail.com

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:05 -05:00
Qiujun Huang b3ca59f6fe tracing: Update trace_ignore_this_task() kernel-doc comment
Update kernel-doc parameter after
commit b3b1e6eded ("ftrace: Create set_ftrace_notrace_pid to not trace tasks")
added @filtered_no_pids.

Link: https://lkml.kernel.org/r/20201231153558.4804-1-hqjagain@gmail.com

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02 17:02:05 -05:00
Linus Torvalds 7d36ccd4bd dma-mapping fix for 5.11
- fix a kernel crash in the new dma-mapping benchmark test (Barry Song)
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Merge tag 'dma-mapping-5.11-1' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fix from Christoph Hellwig:
 "Fix a kernel crash in the new dma-mapping benchmark test (Barry Song)"

* tag 'dma-mapping-5.11-1' of git://git.infradead.org/users/hch/dma-mapping:
  dma-mapping: benchmark: fix kernel crash when dma_map_single fails
2021-02-02 10:40:20 -08:00
Linus Torvalds a992562872 Networking fixes for 5.11-rc7, including fixes from bpf and mac80211
trees.
 
 Current release - regressions:
 
  - ip_tunnel: fix mtu calculation
 
  - mlx5: fix function calculation for page trees
 
 Previous releases - regressions:
 
  - vsock: fix the race conditions in multi-transport support
 
  - neighbour: prevent a dead entry from updating gc_list
 
  - dsa: mv88e6xxx: override existent unicast portvec in port_fdb_add
 
 Previous releases - always broken:
 
  - bpf, cgroup: two copy_{from,to}_user() warn_on_once splats for BPF
                 cgroup getsockopt infra when user space is trying
 		to race against optlen, from Loris Reiff.
 
  - bpf: add missing fput() in BPF inode storage map update helper
 
  - udp: ipv4: manipulate network header of NATed UDP GRO fraglist
 
  - mac80211: fix station rate table updates on assoc
 
  - r8169: work around RTL8125 UDP HW bug
 
  - igc: report speed and duplex as unknown when device is runtime
         suspended
 
  - rxrpc: fix deadlock around release of dst cached on udp tunnel
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.11-rc7, including fixes from bpf and mac80211
  trees.

  Current release - regressions:

   - ip_tunnel: fix mtu calculation

   - mlx5: fix function calculation for page trees

  Previous releases - regressions:

   - vsock: fix the race conditions in multi-transport support

   - neighbour: prevent a dead entry from updating gc_list

   - dsa: mv88e6xxx: override existent unicast portvec in port_fdb_add

  Previous releases - always broken:

   - bpf, cgroup: two copy_{from,to}_user() warn_on_once splats for BPF
     cgroup getsockopt infra when user space is trying to race against
     optlen, from Loris Reiff.

   - bpf: add missing fput() in BPF inode storage map update helper

   - udp: ipv4: manipulate network header of NATed UDP GRO fraglist

   - mac80211: fix station rate table updates on assoc

   - r8169: work around RTL8125 UDP HW bug

   - igc: report speed and duplex as unknown when device is runtime
     suspended

   - rxrpc: fix deadlock around release of dst cached on udp tunnel"

* tag 'net-5.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (36 commits)
  net: hsr: align sup_multicast_addr in struct hsr_priv to u16 boundary
  net: ipa: fix two format specifier errors
  net: ipa: use the right accessor in ipa_endpoint_status_skip()
  net: ipa: be explicit about endianness
  net: ipa: add a missing __iomem attribute
  net: ipa: pass correct dma_handle to dma_free_coherent()
  r8169: fix WoL on shutdown if CONFIG_DEBUG_SHIRQ is set
  net/rds: restrict iovecs length for RDS_CMSG_RDMA_ARGS
  net: mvpp2: TCAM entry enable should be written after SRAM data
  net: lapb: Copy the skb before sending a packet
  net/mlx5e: Release skb in case of failure in tc update skb
  net/mlx5e: Update max_opened_tc also when channels are closed
  net/mlx5: Fix leak upon failure of rule creation
  net/mlx5: Fix function calculation for page trees
  docs: networking: swap words in icmp_errors_use_inbound_ifaddr doc
  udp: ipv4: manipulate network header of NATed UDP GRO fraglist
  net: ip_tunnel: fix mtu calculation
  vsock: fix the race conditions in multi-transport support
  net: sched: replaced invalid qdisc tree flush helper in qdisc_replace
  ibmvnic: device remove has higher precedence over reset
  ...
2021-02-02 10:26:09 -08:00
Kan Liang 2a6c6b7d7a perf/core: Add PERF_SAMPLE_WEIGHT_STRUCT
Current PERF_SAMPLE_WEIGHT sample type is very useful to expresses the
cost of an action represented by the sample. This allows the profiler
to scale the samples to be more informative to the programmer. It could
also help to locate a hotspot, e.g., when profiling by memory latencies,
the expensive load appear higher up in the histograms. But current
PERF_SAMPLE_WEIGHT sample type is solely determined by one factor. This
could be a problem, if users want two or more factors to contribute to
the weight. For example, Golden Cove core PMU can provide both the
instruction latency and the cache Latency information as factors for the
memory profiling.

For current X86 platforms, although meminfo::latency is defined as a
u64, only the lower 32 bits include the valid data in practice (No
memory access could last than 4G cycles). The higher 32 bits can be used
to store new factors.

Add a new sample type, PERF_SAMPLE_WEIGHT_STRUCT, to indicate the new
sample weight structure. It shares the same space as the
PERF_SAMPLE_WEIGHT sample type.

Users can apply either the PERF_SAMPLE_WEIGHT sample type or the
PERF_SAMPLE_WEIGHT_STRUCT sample type to retrieve the sample weight, but
they cannot apply both sample types simultaneously.

Currently, only X86 and PowerPC use the PERF_SAMPLE_WEIGHT sample type.
- For PowerPC, there is nothing changed for the PERF_SAMPLE_WEIGHT
  sample type. There is no effect for the new PERF_SAMPLE_WEIGHT_STRUCT
  sample type. PowerPC can re-struct the weight field similarly later.
- For X86, the same value will be dumped for the PERF_SAMPLE_WEIGHT
  sample type or the PERF_SAMPLE_WEIGHT_STRUCT sample type for now.
  The following patches will apply the new factors for the
  PERF_SAMPLE_WEIGHT_STRUCT sample type.

The field in the union perf_sample_weight should be shared among
different architectures. A generic name is required, but it's hard to
abstract a name that applies to all architectures. For example, on X86,
the fields are to store all kinds of latency. While on PowerPC, it
stores MMCRA[TECX/TECM], which should not be latency. So a general name
prefix 'var$NUM' is used here.

Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1611873611-156687-2-git-send-email-kan.liang@linux.intel.com
2021-02-01 15:31:36 +01:00
Linus Torvalds f7ea44c717 A single fix for the single step reporting regression caused by getting the
condition wrong when moving SYSCALL_EMU away from TIF flags.
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Merge tag 'core-urgent-2021-01-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull single stepping fix from Thomas Gleixner:
 "A single fix for the single step reporting regression caused by
  getting the condition wrong when moving SYSCALL_EMU away from TIF
  flags"

[ There's apparently another problem too, fix pending ]

* tag 'core-urgent-2021-01-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  entry: Unbreak single step reporting behaviour
2021-01-31 11:39:32 -08:00
Marc Zyngier 4c457e8cb7 genirq/msi: Activate Multi-MSI early when MSI_FLAG_ACTIVATE_EARLY is set
When MSI_FLAG_ACTIVATE_EARLY is set (which is the case for PCI),
__msi_domain_alloc_irqs() performs the activation of the interrupt (which
in the case of PCI results in the endpoint being programmed) as soon as the
interrupt is allocated.

But it appears that this is only done for the first vector, introducing an
inconsistent behaviour for PCI Multi-MSI.

Fix it by iterating over the number of vectors allocated to each MSI
descriptor. This is easily achieved by introducing a new
"for_each_msi_vector" iterator, together with a tiny bit of refactoring.

Fixes: f3b0946d62 ("genirq/msi: Make sure PCI MSIs are activated early")
Reported-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210123122759.1781359-1-maz@kernel.org
2021-01-30 01:22:31 +01:00
Wang ShaoBo 0188b87899 kretprobe: Avoid re-registration of the same kretprobe earlier
Our system encountered a re-init error when re-registering same kretprobe,
where the kretprobe_instance in rp->free_instances is illegally accessed
after re-init.

Implementation to avoid re-registration has been introduced for kprobe
before, but lags for register_kretprobe(). We must check if kprobe has
been re-registered before re-initializing kretprobe, otherwise it will
destroy the data struct of kretprobe registered, which can lead to memory
leak, system crash, also some unexpected behaviors.

We use check_kprobe_rereg() to check if kprobe has been re-registered
before running register_kretprobe()'s body, for giving a warning message
and terminate registration process.

Link: https://lkml.kernel.org/r/20210128124427.2031088-1-bobo.shaobowang@huawei.com

Cc: stable@vger.kernel.org
Fixes: 1f0ab40976 ("kprobes: Prevent re-registration of the same kprobe")
[ The above commit should have been done for kretprobes too ]
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@linux.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Signed-off-by: Cheng Jian <cj.chengjian@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-29 17:29:16 -05:00
Linus Torvalds 32b0c410cd Power management fixes for 5.11-rc6
- Fix a deadlock caused by attempting to acquire the same mutex
    twice in a row in the "kexec jump" code (Baoquan He).
 
  - Modify the hibernation image saving code to flush the unwritten
    data to the swap storage later so as to avoid failing to write the
    image signature which is possible in some cases (Laurent Badel).
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Merge tag 'pm-5.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix a deadlock in the 'kexec jump' code and address a possible
  hibernation image creation issue.

  Specifics:

   - Fix a deadlock caused by attempting to acquire the same mutex twice
     in a row in the "kexec jump" code (Baoquan He)

   - Modify the hibernation image saving code to flush the unwritten
     data to the swap storage later so as to avoid failing to write the
     image signature which is possible in some cases (Laurent Badel)"

* tag 'pm-5.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM: hibernate: flush swap writer after marking
  kernel: kexec: remove the lock operation of system_transition_mutex
2021-01-29 13:30:09 -08:00
Masami Hiramatsu 97c753e62e tracing/kprobe: Fix to support kretprobe events on unloaded modules
Fix kprobe_on_func_entry() returns error code instead of false so that
register_kretprobe() can return an appropriate error code.

append_trace_kprobe() expects the kprobe registration returns -ENOENT
when the target symbol is not found, and it checks whether the target
module is unloaded or not. If the target module doesn't exist, it
defers to probe the target symbol until the module is loaded.

However, since register_kretprobe() returns -EINVAL instead of -ENOENT
in that case, it always fail on putting the kretprobe event on unloaded
modules. e.g.

Kprobe event:
/sys/kernel/debug/tracing # echo p xfs:xfs_end_io >> kprobe_events
[   16.515574] trace_kprobe: This probe might be able to register after target module is loaded. Continue.

Kretprobe event: (p -> r)
/sys/kernel/debug/tracing # echo r xfs:xfs_end_io >> kprobe_events
sh: write error: Invalid argument
/sys/kernel/debug/tracing # cat error_log
[   41.122514] trace_kprobe: error: Failed to register probe event
  Command: r xfs:xfs_end_io
             ^

To fix this bug, change kprobe_on_func_entry() to detect symbol lookup
failure and return -ENOENT in that case. Otherwise it returns -EINVAL
or 0 (succeeded, given address is on the entry).

Link: https://lkml.kernel.org/r/161176187132.1067016.8118042342894378981.stgit@devnote2

Cc: stable@vger.kernel.org
Fixes: 59158ec4ae ("tracing/kprobes: Check the probe on unloaded module correctly")
Reported-by: Jianlin Lv <Jianlin.Lv@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-29 15:39:48 -05:00
Viktor Rosendahl da7f84cdf0 tracing: Use pause-on-trace with the latency tracers
Eaerlier, tracing was disabled when reading the trace file. This behavior
was changed with:

commit 06e0a548ba ("tracing: Do not disable tracing when reading the
trace file").

This doesn't seem to work with the latency tracers.

The above mentioned commit dit not only change the behavior but also added
an option to emulate the old behavior. The idea with this patch is to
enable this pause-on-trace option when the latency tracers are used.

Link: https://lkml.kernel.org/r/20210119164344.37500-2-Viktor.Rosendahl@bmw.de

Cc: stable@vger.kernel.org
Fixes: 06e0a548ba ("tracing: Do not disable tracing when reading the trace file")
Signed-off-by: Viktor Rosendahl <Viktor.Rosendahl@bmw.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-29 15:35:33 -05:00
Steven Rostedt (VMware) 7e0a922046 fgraph: Initialize tracing_graph_pause at task creation
On some archs, the idle task can call into cpu_suspend(). The cpu_suspend()
will disable or pause function graph tracing, as there's some paths in
bringing down the CPU that can have issues with its return address being
modified. The task_struct structure has a "tracing_graph_pause" atomic
counter, that when set to something other than zero, the function graph
tracer will not modify the return address.

The problem is that the tracing_graph_pause counter is initialized when the
function graph tracer is enabled. This can corrupt the counter for the idle
task if it is suspended in these architectures.

   CPU 1				CPU 2
   -----				-----
  do_idle()
    cpu_suspend()
      pause_graph_tracing()
          task_struct->tracing_graph_pause++ (0 -> 1)

				start_graph_tracing()
				  for_each_online_cpu(cpu) {
				    ftrace_graph_init_idle_task(cpu)
				      task-struct->tracing_graph_pause = 0 (1 -> 0)

      unpause_graph_tracing()
          task_struct->tracing_graph_pause-- (0 -> -1)

The above should have gone from 1 to zero, and enabled function graph
tracing again. But instead, it is set to -1, which keeps it disabled.

There's no reason that the field tracing_graph_pause on the task_struct can
not be initialized at boot up.

Cc: stable@vger.kernel.org
Fixes: 380c4b1411 ("tracing/function-graph-tracer: append the tracing_graph_flag")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211339
Reported-by: pierre.gondois@arm.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-29 15:07:32 -05:00
Nikolay Borisov 442187f3c2 locking/rwsem: Remove empty rwsem.h
This is a leftover from 7f26482a87 ("locking/percpu-rwsem: Remove the embedded rwsem")

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20210126101721.976027-1-nborisov@suse.com
2021-01-29 20:02:34 +01:00
Jakub Kicinski 06cc6e5dc6 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2021-01-29

1) Fix two copy_{from,to}_user() warn_on_once splats for BPF cgroup getsockopt
   infra when user space is trying to race against optlen, from Loris Reiff.

2) Fix a missing fput() in BPF inode storage map update helper, from Pan Bian.

3) Fix a build error on unresolved symbols on disabled networking / keys LSM
   hooks, from Mikko Ylinen.

4) Fix preload BPF prog build when the output directory from make points to a
   relative path, from Quentin Monnet.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf, preload: Fix build when $(O) points to a relative path
  bpf: Drop disabled LSM hooks from the sleepable set
  bpf, inode_storage: Put file handler if no storage was found
  bpf, cgroup: Fix problematic bounds check
  bpf, cgroup: Fix optlen WARN_ON_ONCE toctou
====================

Link: https://lore.kernel.org/r/20210129001556.6648-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-28 21:07:45 -08:00
Viresh Kumar be65de6b03 fs: Remove dcookies support
The dcookies stuff was only used by the kernel's old oprofile code. Now
that oprofile's support is removed from the kernel, there is no need for
dcookies as well. Remove it.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Robert Richter <rric@kernel.org>
Acked-by: William Cohen <wcohen@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
2021-01-29 10:06:46 +05:30
Tobias Klauser 61ca36c8c4 bpf: Simplify cases in bpf_base_func_proto
!perfmon_capable() is checked before the last switch(func_id) in
bpf_base_func_proto. Thus, the cases BPF_FUNC_trace_printk and
BPF_FUNC_snprintf_btf can be moved to that last switch(func_id) to omit
the inline !perfmon_capable() checks.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210127174615.3038-1-tklauser@distanz.ch
2021-01-29 02:20:28 +01:00
Jakub Kicinski c358f95205 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/can/dev.c
  b552766c87 ("can: dev: prevent potential information leak in can_fill_info()")
  3e77f70e73 ("can: dev: move driver related infrastructure into separate subdir")
  0a042c6ec9 ("can: dev: move netlink related code into seperate file")

  Code move.

drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
  57ac4a31c4 ("net/mlx5e: Correctly handle changing the number of queues when the interface is down")
  214baf2287 ("net/mlx5e: Support HTB offload")

  Adjacent code changes

net/switchdev/switchdev.c
  20776b465c ("net: switchdev: don't set port_obj_info->handled true when -EOPNOTSUPP")
  ffb68fc58e ("net: switchdev: remove the transaction structure from port object notifiers")
  bae33f2b5a ("net: switchdev: remove the transaction structure from port attributes")

  Transaction parameter gets dropped otherwise keep the fix.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-28 17:09:31 -08:00
Yuxuan Shui 41c1a06d1d entry: Unbreak single step reporting behaviour
The move of TIF_SYSCALL_EMU to SYSCALL_WORK_SYSCALL_EMU broke single step
reporting. The original code reported the single step when TIF_SINGLESTEP
was set and TIF_SYSCALL_EMU was not set. The SYSCALL_WORK conversion got
the logic wrong and now the reporting only happens when both bits are set.

Restore the original behaviour.

[ tglx: Massaged changelog and dropped the pointless double negation ]

Fixes: 64eb35f701 ("ptrace: Migrate TIF_SYSCALL_EMU to use SYSCALL_WORK flag")
Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Link: https://lore.kernel.org/r/877do3gaq9.fsf@m5Zedd9JOGzJrf0
2021-01-28 13:46:55 +01:00
Alex Shi bf594bf400 locking/rtmutex: Add missing kernel-doc markup
To fix the following issues:
kernel/locking/rtmutex.c:1612: warning: Function parameter or member
'lock' not described in '__rt_mutex_futex_unlock'
kernel/locking/rtmutex.c:1612: warning: Function parameter or member
'wake_q' not described in '__rt_mutex_futex_unlock'
kernel/locking/rtmutex.c:1675: warning: Function parameter or member
'name' not described in '__rt_mutex_init'
kernel/locking/rtmutex.c:1675: warning: Function parameter or member
'key' not described in '__rt_mutex_init'

[ tglx: Change rt lock to rt_mutex for consistency sake ]

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/1605257895-5536-2-git-send-email-alex.shi@linux.alibaba.com
2021-01-28 13:20:18 +01:00
Jangwoong Kim 0f9438503e futex: Remove unneeded gotos
Get rid of gotos that do not contain any cleanup. These were not removed in
commit 9180bd467f ("futex: Remove put_futex_key()").

Signed-off-by: Jangwoong Kim <6812skiii@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201230122953.10473-1-6812skiii@gmail.com
2021-01-28 13:20:18 +01:00
Alejandro Colomar 1ce53e2c2a futex: Change utime parameter to be 'const ... *'
futex(2) says that 'utime' is a pointer to 'const'.  The implementation
doesn't use 'const'; however, it _never_ modifies the contents of utime.

- futex() either uses 'utime' as a pointer to struct or as a 'u32'.

- In case it's used as a 'u32', it makes a copy of it, and of course it is
  not dereferenced.

- In case it's used as a 'struct __kernel_timespec __user *', the pointer
  is not dereferenced inside the futex() definition, and it is only passed
  to a function: get_timespec64(), which accepts a 'const struct
  __kernel_timespec __user *'.

[ tglx: Make the same change to the compat syscall and fixup the prototypes. ]

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201128123945.4592-1-alx.manpages@gmail.com
2021-01-28 13:20:18 +01:00
Emil Renner Berthing c260954177 genirq: Use new tasklet API for resend_tasklet
This converts the resend_tasklet to use the new API in
commit 12cc923f1c ("tasklet: Introduce new initialization API")

The new API changes the argument passed to the callback function, but
fortunately the argument isn't used so it is straight forward to use
DECLARE_TASKLET() rather than DECLARE_TASKLET_OLD().

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210123182456.6521-1-esmil@mailme.dk
2021-01-28 11:18:04 +01:00
Yang Yang 127c8c5f05 audit: Make audit_filter_syscall() return void
No invoker uses the return value of audit_filter_syscall().
So make it return void, and amend the comment of
audit_filter_syscall().

Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
[PM: removed the changelog from the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-01-27 21:55:14 -05:00
Stanislav Fomichev 772412176f bpf: Allow rewriting to ports under ip_unprivileged_port_start
At the moment, BPF_CGROUP_INET{4,6}_BIND hooks can rewrite user_port
to the privileged ones (< ip_unprivileged_port_start), but it will
be rejected later on in the __inet_bind or __inet6_bind.

Let's add another return value to indicate that CAP_NET_BIND_SERVICE
check should be ignored. Use the same idea as we currently use
in cgroup/egress where bit #1 indicates CN. Instead, for
cgroup/bind{4,6}, bit #1 indicates that CAP_NET_BIND_SERVICE should
be bypassed.

v5:
- rename flags to be less confusing (Andrey Ignatov)
- rework BPF_PROG_CGROUP_INET_EGRESS_RUN_ARRAY to work on flags
  and accept BPF_RET_SET_CN (no behavioral changes)

v4:
- Add missing IPv6 support (Martin KaFai Lau)

v3:
- Update description (Martin KaFai Lau)
- Fix capability restore in selftest (Martin KaFai Lau)

v2:
- Switch to explicit return code (Martin KaFai Lau)

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/20210127193140.3170382-1-sdf@google.com
2021-01-27 18:18:15 -08:00
Menglong Dong 60e578e82b bpf: Change 'BPF_ADD' to 'BPF_AND' in print_bpf_insn()
This 'BPF_ADD' is duplicated, and I belive it should be 'BPF_AND'.

Fixes: 981f94c3e9 ("bpf: Add bitwise atomic instructions")
Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Brendan Jackman <jackmanb@google.com>
Link: https://lore.kernel.org/bpf/20210127022507.23674-1-dong.menglong@zte.com.cn
2021-01-27 22:23:46 +01:00
Zqiang ccf7ce46ab PM: sleep: No need to check PF_WQ_WORKER in thaw_kernel_threads()
Because PF_KTHREAD is set for all wq worker threads, it is
not necessary to check PF_WQ_WORKER in addition to it in
thaw_kernel_threads(), so stop doing that.

Signed-off-by: Zqiang <qiang.zhang@windriver.com>
[ rjw: Subject and changelog rewrite ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-27 19:20:17 +01:00
Mel Gorman bae4ec1364 sched/fair: Move avg_scan_cost calculations under SIS_PROP
As noted by Vincent Guittot, avg_scan_costs are calculated for SIS_PROP
even if SIS_PROP is disabled. Move the time calculations under a SIS_PROP
check and while we are at it, exclude the cost of initialising the CPU
mask from the average scan cost.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20210125085909.4600-3-mgorman@techsingularity.net
2021-01-27 17:26:44 +01:00
Mel Gorman e6e0dc2d54 sched/fair: Remove SIS_AVG_CPU
SIS_AVG_CPU was introduced as a means of avoiding a search when the
average search cost indicated that the search would likely fail. It was
a blunt instrument and disabled by commit 4c77b18cf8 ("sched/fair: Make
select_idle_cpu() more aggressive") and later replaced with a proportional
search depth by commit 1ad3aaf3fc ("sched/core: Implement new approach
to scale select_idle_cpu()").

While there are corner cases where SIS_AVG_CPU is better, it has now been
disabled for almost three years. As the intent of SIS_PROP is to reduce
the time complexity of select_idle_cpu(), lets drop SIS_AVG_CPU and focus
on SIS_PROP as a throttling mechanism.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20210125085909.4600-2-mgorman@techsingularity.net
2021-01-27 17:26:43 +01:00
Valentin Schneider 620a6dc407 sched/topology: Make sched_init_numa() use a set for the deduplicating sort
The deduplicating sort in sched_init_numa() assumes that the first line in
the distance table contains all unique values in the entire table. I've
been trying to pen what this exactly means for the topology, but it's not
straightforward. For instance, topology.c uses this example:

  node   0   1   2   3
    0:  10  20  20  30
    1:  20  10  20  20
    2:  20  20  10  20
    3:  30  20  20  10

  0 ----- 1
  |     / |
  |   /   |
  | /     |
  2 ----- 3

Which works out just fine. However, if we swap nodes 0 and 1:

  1 ----- 0
  |     / |
  |   /   |
  | /     |
  2 ----- 3

we get this distance table:

  node   0  1  2  3
    0:  10 20 20 20
    1:  20 10 20 30
    2:  20 20 10 20
    3:  20 30 20 10

Which breaks the deduplicating sort (non-representative first line). In
this case this would just be a renumbering exercise, but it so happens that
we can have a deduplicating sort that goes through the whole table in O(n²)
at the extra cost of a temporary memory allocation (i.e. any form of set).

The ACPI spec (SLIT) mentions distances are encoded on 8 bits. Following
this, implement the set as a 256-bits bitmap. Should this not be
satisfactory (i.e. we want to support 32-bit values), then we'll have to go
for some other sparse set implementation.

This has the added benefit of letting us allocate just the right amount of
memory for sched_domains_numa_distance[], rather than an arbitrary
(nr_node_ids + 1).

Note: DT binding equivalent (distance-map) decodes distances as 32-bit
values.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210122123943.1217-2-valentin.schneider@arm.com
2021-01-27 17:26:42 +01:00
Qais Yousef 0ae78eec8a sched/eas: Don't update misfit status if the task is pinned
If the task is pinned to a cpu, setting the misfit status means that
we'll unnecessarily continuously attempt to migrate the task but fail.

This continuous failure will cause the balance_interval to increase to
a high value, and eventually cause unnecessary significant delays in
balancing the system when real imbalance happens.

Caught while testing uclamp where rt-app calibration loop was pinned to
cpu 0, shortly after which we spawn another task with high util_clamp
value. The task was failing to migrate after over 40ms of runtime due to
balance_interval unnecessary expanded to a very high value from the
calibration loop.

Not done here, but it could be useful to extend the check for pinning to
verify that the affinity of the task has a cpu that fits. We could end
up in a similar situation otherwise.

Fixes: 3b1baa6496 ("sched/fair: Add 'group_misfit_task' load-balance type")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Acked-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210119120755.2425264-1-qais.yousef@arm.com
2021-01-27 17:26:42 +01:00
Barry Song d17405d52b dma-mapping: benchmark: fix kernel crash when dma_map_single fails
if dma_map_single() fails, kernel will give the below oops since
task_struct has been destroyed and we are running into the memory
corruption due to use-after-free in kthread_stop():

[   48.095310] Unable to handle kernel paging request at virtual address 000000c473548040
[   48.095736] Mem abort info:
[   48.095864]   ESR = 0x96000004
[   48.096025]   EC = 0x25: DABT (current EL), IL = 32 bits
[   48.096268]   SET = 0, FnV = 0
[   48.096401]   EA = 0, S1PTW = 0
[   48.096538] Data abort info:
[   48.096659]   ISV = 0, ISS = 0x00000004
[   48.096820]   CM = 0, WnR = 0
[   48.097079] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000104639000
[   48.098099] [000000c473548040] pgd=0000000000000000, p4d=0000000000000000
[   48.098832] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[   48.099232] Modules linked in:
[   48.099387] CPU: 0 PID: 2 Comm: kthreadd Tainted: G        W
[   48.099887] Hardware name: linux,dummy-virt (DT)
[   48.100078] pstate: 60000005 (nZCv daif -PAN -UAO -TCO BTYPE=--)
[   48.100516] pc : __kmalloc_node+0x214/0x368
[   48.100944] lr : __kmalloc_node+0x1f4/0x368
[   48.101458] sp : ffff800011f0bb80
[   48.101843] x29: ffff800011f0bb80 x28: ffff0000c0098ec0
[   48.102330] x27: 0000000000000000 x26: 00000000001d4600
[   48.102648] x25: ffff0000c0098ec0 x24: ffff800011b6a000
[   48.102988] x23: 00000000ffffffff x22: ffff0000c0098ec0
[   48.103333] x21: ffff8000101d7a54 x20: 0000000000000dc0
[   48.103657] x19: ffff0000c0001e00 x18: 0000000000000000
[   48.104069] x17: 0000000000000000 x16: 0000000000000000
[   48.105449] x15: 000001aa0304e7b9 x14: 00000000000003b1
[   48.106401] x13: ffff8000122d5000 x12: ffff80001228d000
[   48.107296] x11: ffff0000c0154340 x10: 0000000000000000
[   48.107862] x9 : ffff80000fffffff x8 : ffff0000c473527f
[   48.108326] x7 : ffff800011e62f58 x6 : ffff0000c01c8ed8
[   48.108778] x5 : ffff0000c0098ec0 x4 : 0000000000000000
[   48.109223] x3 : 00000000001d4600 x2 : 0000000000000040
[   48.109656] x1 : 0000000000000001 x0 : ff0000c473548000
[   48.110104] Call trace:
[   48.110287]  __kmalloc_node+0x214/0x368
[   48.110493]  __vmalloc_node_range+0xc4/0x298
[   48.110805]  copy_process+0x2c8/0x15c8
[   48.111133]  kernel_clone+0x5c/0x3c0
[   48.111373]  kernel_thread+0x64/0x90
[   48.111604]  kthreadd+0x158/0x368
[   48.111810]  ret_from_fork+0x10/0x30
[   48.112336] Code: 17ffffe9 b9402a62 b94008a1 11000421 (f8626802)
[   48.112884] ---[ end trace d4890e21e75419d5 ]---

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-01-27 17:18:38 +01:00
Stephen Zhang e9ad2eb3d9 workqueue: Use %s instead of function name
It is better to replace the function name with %s, in case the function
name changes.

Signed-off-by: Stephen Zhang <stephenzhangzsd@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-27 09:42:48 -05:00
Quentin Monnet 150a27328b bpf, preload: Fix build when $(O) points to a relative path
Building the kernel with CONFIG_BPF_PRELOAD, and by providing a relative
path for the output directory, may fail with the following error:

  $ make O=build bindeb-pkg
  ...
  /.../linux/tools/scripts/Makefile.include:5: *** O=build does not exist.  Stop.
  make[7]: *** [/.../linux/kernel/bpf/preload/Makefile:9: kernel/bpf/preload/libbpf.a] Error 2
  make[6]: *** [/.../linux/scripts/Makefile.build:500: kernel/bpf/preload] Error 2
  make[5]: *** [/.../linux/scripts/Makefile.build:500: kernel/bpf] Error 2
  make[4]: *** [/.../linux/Makefile:1799: kernel] Error 2
  make[4]: *** Waiting for unfinished jobs....

In the case above, for the "bindeb-pkg" target, the error is produced by
the "dummy" check in Makefile.include, called from libbpf's Makefile.
This check changes directory to $(PWD) before checking for the existence
of $(O). But at this step we have $(PWD) pointing to "/.../linux/build",
and $(O) pointing to "build". So the Makefile.include tries in fact to
assert the existence of a directory named "/.../linux/build/build",
which does not exist.

Note that the error does not occur for all make targets and
architectures combinations. This was observed on x86 for "bindeb-pkg",
or for a regular build for UML [0].

Here are some details. The root Makefile recursively calls itself once,
after changing directory to $(O). The content for the variable $(PWD) is
preserved across recursive calls to make, so it is unchanged at this
step. For "bindeb-pkg", $(PWD) is eventually updated because the target
writes a new Makefile (as debian/rules) and calls it indirectly through
dpkg-buildpackage. This script does not preserve $(PWD), which is reset
to the current working directory when the target in debian/rules is
called.

Although not investigated, it seems likely that something similar causes
UML to change its value for $(PWD).

Non-trivial fixes could be to remove the use of $(PWD) from the "dummy"
check, or to make sure that $(PWD) and $(O) are preserved or updated to
always play well and form a valid $(PWD)/$(O) path across the different
targets and architectures. Instead, we take a simpler approach and just
update $(O) when calling libbpf's Makefile, so it points to an absolute
path which should always resolve for the "dummy" check run (through
includes) by that Makefile.

David Gow previously posted a slightly different version of this patch
as a RFC [0], two months ago or so.

  [0] https://lore.kernel.org/bpf/20201119085022.3606135-1-davidgow@google.com/t/#u

Fixes: d71fa5c976 ("bpf: Add kernel module with user mode driver that populates bpffs.")
Reported-by: David Gow <davidgow@google.com>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/bpf/20210126161320.24561-1-quentin@isovalent.com
2021-01-26 23:13:25 +01:00
Mikko Ylinen 78031381ae bpf: Drop disabled LSM hooks from the sleepable set
Some networking and keys LSM hooks are conditionally enabled
and when building the new sleepable BPF LSM hooks with those
LSM hooks disabled, the following build error occurs:

  BTFIDS  vmlinux
  FAILED unresolved symbol bpf_lsm_socket_socketpair

To fix the error, conditionally add the relevant networking/keys
LSM hooks to the sleepable set.

Fixes: 423f16108c ("bpf: Augment the set of sleepable LSM hooks")
Signed-off-by: Mikko Ylinen <mikko.ylinen@linux.intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210125063936.89365-1-mikko.ylinen@linux.intel.com
2021-01-26 17:08:50 +01:00
Thomas Gleixner 34b1a1ce14 futex: Handle faults correctly for PI futexes
fixup_pi_state_owner() tries to ensure that the state of the rtmutex,
pi_state and the user space value related to the PI futex are consistent
before returning to user space. In case that the user space value update
faults and the fault cannot be resolved by faulting the page in via
fault_in_user_writeable() the function returns with -EFAULT and leaves
the rtmutex and pi_state owner state inconsistent.

A subsequent futex_unlock_pi() operates on the inconsistent pi_state and
releases the rtmutex despite not owning it which can corrupt the RB tree of
the rtmutex and cause a subsequent kernel stack use after free.

It was suggested to loop forever in fixup_pi_state_owner() if the fault
cannot be resolved, but that results in runaway tasks which is especially
undesired when the problem happens due to a programming error and not due
to malice.

As the user space value cannot be fixed up, the proper solution is to make
the rtmutex and the pi_state consistent so both have the same owner. This
leaves the user space value out of sync. Any subsequent operation on the
futex will fail because the 10th rule of PI futexes (pi_state owner and
user space value are consistent) has been violated.

As a consequence this removes the inept attempts of 'fixing' the situation
in case that the current task owns the rtmutex when returning with an
unresolvable fault by unlocking the rtmutex which left pi_state::owner and
rtmutex::owner out of sync in a different and only slightly less dangerous
way.

Fixes: 1b7558e457 ("futexes: fix fault handling in futex_lock_pi")
Reported-by: gzobqq@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:11:00 +01:00
Thomas Gleixner f2dac39d93 futex: Simplify fixup_pi_state_owner()
Too many gotos already and an upcoming fix would make it even more
unreadable.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:10:59 +01:00
Thomas Gleixner 6ccc84f917 futex: Use pi_state_update_owner() in put_pi_state()
No point in open coding it. This way it gains the extra sanity checks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:10:59 +01:00
Thomas Gleixner 2156ac1934 rtmutex: Remove unused argument from rt_mutex_proxy_unlock()
Nothing uses the argument. Remove it as preparation to use
pi_state_update_owner().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:10:58 +01:00
Thomas Gleixner c5cade200a futex: Provide and use pi_state_update_owner()
Updating pi_state::owner is done at several places with the same
code. Provide a function for it and use that at the obvious places.

This is also a preparation for a bug fix to avoid yet another copy of the
same code or alternatively introducing a completely unpenetratable mess of
gotos.

Originally-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:10:58 +01:00
Thomas Gleixner 04b79c5520 futex: Replace pointless printk in fixup_owner()
If that unexpected case of inconsistent arguments ever happens then the
futex state is left completely inconsistent and the printk is not really
helpful. Replace it with a warning and make the state consistent.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:10:58 +01:00
Thomas Gleixner 12bb3f7f1b futex: Ensure the correct return value from futex_lock_pi()
In case that futex_lock_pi() was aborted by a signal or a timeout and the
task returned without acquiring the rtmutex, but is the designated owner of
the futex due to a concurrent futex_unlock_pi() fixup_owner() is invoked to
establish consistent state. In that case it invokes fixup_pi_state_owner()
which in turn tries to acquire the rtmutex again. If that succeeds then it
does not propagate this success to fixup_owner() and futex_lock_pi()
returns -EINTR or -ETIMEOUT despite having the futex locked.

Return success from fixup_pi_state_owner() in all cases where the current
task owns the rtmutex and therefore the futex and propagate it correctly
through fixup_owner(). Fixup the other callsite which does not expect a
positive return value.

Fixes: c1e2f0eaf0 ("futex: Avoid violating the 10th rule of futex")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:10:58 +01:00
Lukas Bulwahn 8f0bfc25c9 watch_queue: rectify kernel-doc for init_watch()
The command './scripts/kernel-doc -none kernel/watch_queue.c'
reported a mismatch in the kernel-doc of init_watch().

Rectify the kernel-doc, such that no issues remain for watch_queue.c.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2021-01-26 11:16:34 +00:00
Lukas Bulwahn 9bc284ca0b printk: rectify kernel-doc for prb_rec_init_wr()
The command 'find ./kernel/printk/ | xargs ./scripts/kernel-doc -none'
reported a mismatch with the kernel-doc of prb_rec_init_wr().

Rectify the kernel-doc, such that no issues remain for ./kernel/printk/.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210125081748.19903-1-lukas.bulwahn@gmail.com
2021-01-26 11:17:51 +01:00
Linus Torvalds 007ad27d7b Printk urgent fixup for 5.11-rc6
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Merge tag 'printk-for-5.11-urgent-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk fix from Petr Mladek:
 "The fix of a potential buffer overflow in 5.11-rc5 introduced another
  one. The trailing '\0' might be written up to the message "len" past
  the buffer. Fortunately, it is not that easy to hit.

  Most readers use 1kB buffers for a single message. Typical messages
  fit into the temporary buffer with enough reserve.

  Also readers do not rely on the '\0'. It is related to the previous
  fix. Some readers required the space for the trailing '\0'. We decided
  to write it there to avoid such regressions in the future.

  The most realistic victims are dumpers using kmsg_dump_get_buffer().
  They are filling the entire buffer with as many messages as possible.
  They are typically used when handling panic()"

* tag 'printk-for-5.11-urgent-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: fix string termination for record_print_text()
2021-01-25 10:19:40 -08:00
Laurent Badel fef9c8d28e PM: hibernate: flush swap writer after marking
Flush the swap writer after, not before, marking the files, to ensure the
signature is properly written.

Fixes: 6f612af578 ("PM / Hibernate: Group swap ops")
Signed-off-by: Laurent Badel <laurentbadel@eaton.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 18:52:30 +01:00
Baoquan He 56c91a1843 kernel: kexec: remove the lock operation of system_transition_mutex
Function kernel_kexec() is called with lock system_transition_mutex
held in reboot system call. While inside kernel_kexec(), it will
acquire system_transition_mutex agin. This will lead to dead lock.

The dead lock should be easily triggered, it hasn't caused any
failure report just because the feature 'kexec jump' is almost not
used by anyone as far as I know. An inquiry can be made about who
is using 'kexec jump' and where it's used. Before that, let's simply
remove the lock operation inside CONFIG_KEXEC_JUMP ifdeffery scope.

Fixes: 55f2503c3b ("PM / reboot: Eliminate race between reboot and suspend")
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Pingfan Liu <kernelfans@gmail.com>
Cc: 4.19+ <stable@vger.kernel.org> # 4.19+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 18:40:37 +01:00
Petr Mladek 61bb17da44 Merge branch 'printk-rework' into for-linus 2021-01-25 14:29:35 +01:00
John Ogness 08d60e5999 printk: fix string termination for record_print_text()
Commit f0e386ee0c ("printk: fix buffer overflow potential for
print_text()") added string termination in record_print_text().
However it used the wrong base pointer for adding the terminator.
This led to a 0-byte being written somewhere beyond the buffer.

Use the correct base pointer when adding the terminator.

Fixes: f0e386ee0c ("printk: fix buffer overflow potential for print_text()")
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210124202728.4718-1-john.ogness@linutronix.de
2021-01-25 10:37:08 +01:00
Christoph Hellwig 309dca309f block: store a block_device pointer in struct bio
Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device.  From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24 18:17:20 -07:00
Linus Torvalds e68061375f - Fix a kernel panic in mips-cpu due to invalid irq domain hierarchy.
- Fix to not lose IPIs on bcm2836.
 
  - Fix for a bogus marking of ITS devices as shared due to unitialized
    stack variable.
 
  - Clear a phantom interrupt on qcom-pdc to unblock suspend.
 
  - Small cleanups, warning and build fixes.
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Merge tag 'irq_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Borislav Petkov:

 - Fix a kernel panic in mips-cpu due to invalid irq domain hierarchy.

 - Fix to not lose IPIs on bcm2836.

 - Fix for a bogus marking of ITS devices as shared due to unitialized
   stack variable.

 - Clear a phantom interrupt on qcom-pdc to unblock suspend.

 - Small cleanups, warning and build fixes.

* tag 'irq_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Export irq_check_status_bit()
  irqchip/mips-cpu: Set IPI domain parent chip
  irqchip/pruss: Simplify the TI_PRUSS_INTC Kconfig
  irqchip/loongson-liointc: Fix build warnings
  driver core: platform: Add extra error check in devm_platform_get_irqs_affinity()
  irqchip/bcm2836: Fix IPI acknowledgement after conversion to handle_percpu_devid_irq
  irqchip/irq-sl28cpld: Convert comma to semicolon
  genirq/msi: Initialize msi_alloc_info before calling msi_domain_prepare_irqs()
2021-01-24 10:24:20 -08:00
Linus Torvalds 24c56ee06c - Correct the marking of kthreads which are supposed to run on a specific,
single CPU vs such which are affine to only one CPU, mark per-cpu workqueue
  threads as such and make sure that marking "survives" CPU hotplug. Fix CPU
  hotplug issues with such kthreads.
 
  - A fix to not push away tasks on CPUs coming online.
 
  - Have workqueue CPU hotplug code use cpu_possible_mask when breaking affinity
    on CPU offlining so that pending workers can finish on newly arrived onlined
    CPUs too.
 
  - Dump tasks which haven't vacated a CPU which is currently being unplugged.
 
  - Register a special scale invariance callback which gets called on resume
  from RAM to read out APERF/MPERF after resume and thus make the schedutil
  scaling governor more precise.
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Merge tag 'sched_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fixes from Borislav Petkov:

 - Correct the marking of kthreads which are supposed to run on a
   specific, single CPU vs such which are affine to only one CPU, mark
   per-cpu workqueue threads as such and make sure that marking
   "survives" CPU hotplug. Fix CPU hotplug issues with such kthreads.

 - A fix to not push away tasks on CPUs coming online.

 - Have workqueue CPU hotplug code use cpu_possible_mask when breaking
   affinity on CPU offlining so that pending workers can finish on newly
   arrived onlined CPUs too.

 - Dump tasks which haven't vacated a CPU which is currently being
   unplugged.

 - Register a special scale invariance callback which gets called on
   resume from RAM to read out APERF/MPERF after resume and thus make
   the schedutil scaling governor more precise.

* tag 'sched_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Relax the set_cpus_allowed_ptr() semantics
  sched: Fix CPU hotplug / tighten is_per_cpu_kthread()
  sched: Prepare to use balance_push in ttwu()
  workqueue: Restrict affinity change to rescuer
  workqueue: Tag bound workers with KTHREAD_IS_PER_CPU
  kthread: Extract KTHREAD_IS_PER_CPU
  sched: Don't run cpu-online with balance_push() enabled
  workqueue: Use cpu_possible_mask instead of cpu_active_mask to break affinity
  sched/core: Print out straggler tasks in sched_cpu_dying()
  x86: PM: Register syscore_ops for scale invariance
2021-01-24 10:09:20 -08:00
Linus Torvalds 025929f468 - Fix an integer overflow in the NTP RTC synchronization which lead to latter
happening every 2 seconds instead of the intended every 11 minutes.
 
  - Get rid of now unused get_seconds().
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Merge tag 'timers_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Borislav Petkov:

 - Fix an integer overflow in the NTP RTC synchronization which led to
   the latter happening every 2 seconds instead of the intended every 11
   minutes.

 - Get rid of now unused get_seconds().

* tag 'timers_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ntp: Fix RTC synchronization on 32-bit platforms
  timekeeping: Remove unused get_seconds()
2021-01-24 09:58:38 -08:00
Linus Torvalds 17b6c49da3 - Add a new Intel model number for Alder Lake
- Differentiate which aspects of the FPU state get saved/restored when the FPU
    is used in-kernel and fix a boot crash on K7 due to early MXCSR access before
    CR4.OSFXSR is even set.
 
  - A couple of noinstr annotation fixes
 
  - Correct die ID setting on AMD for users of topology information which need
    the correct die ID
 
  - A SEV-ES fix to handle string port IO to/from kernel memory properly
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Merge tag 'x86_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:

 - Add a new Intel model number for Alder Lake

 - Differentiate which aspects of the FPU state get saved/restored when
   the FPU is used in-kernel and fix a boot crash on K7 due to early
   MXCSR access before CR4.OSFXSR is even set.

 - A couple of noinstr annotation fixes

 - Correct die ID setting on AMD for users of topology information which
   need the correct die ID

 - A SEV-ES fix to handle string port IO to/from kernel memory properly

* tag 'x86_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Add another Alder Lake CPU to the Intel family
  x86/mmx: Use KFPU_387 for MMX string operations
  x86/fpu: Add kernel_fpu_begin_mask() to selectively initialize state
  x86/topology: Make __max_die_per_package available unconditionally
  x86: __always_inline __{rd,wr}msr()
  x86/mce: Remove explicit/superfluous tracing
  locking/lockdep: Avoid noinstr warning for DEBUG_LOCKDEP
  locking/lockdep: Cure noinstr fail
  x86/sev: Fix nonistr violation
  x86/entry: Fix noinstr fail
  x86/cpu/amd: Set __max_die_per_package on AMD
  x86/sev-es: Handle string port IO to kernel memory properly
2021-01-24 09:46:05 -08:00
Linus Torvalds c509ce2378 for-linus-2021-01-24
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Merge tag 'for-linus-2021-01-24' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull misc fixes from Christian Brauner:

 - Jann reported sparse complaints because of a missing __user
   annotation in a helper we added way back when we added
   pidfd_send_signal() to avoid compat syscall handling. Fix it.

 - Yanfei replaces a reference in a comment to the _do_fork() helper I
   removed a while ago with a reference to the new kernel_clone()
   replacement

 - Alexander Guril added a simple coding style fix

* tag 'for-linus-2021-01-24' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  kthread: remove comments about old _do_fork() helper
  Kernel: fork.c: Fix coding style: Do not use {} around single-line statements
  signal: Add missing __user annotation to copy_siginfo_from_user_any
2021-01-24 09:35:28 -08:00
Christian Brauner 549c729771
fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Christian Brauner 71bc356f93
commoncap: handle idmapped mounts
When interacting with user namespace and non-user namespace aware
filesystem capabilities the vfs will perform various security checks to
determine whether or not the filesystem capabilities can be used by the
caller, whether they need to be removed and so on. The main
infrastructure for this resides in the capability codepaths but they are
called through the LSM security infrastructure even though they are not
technically an LSM or optional. This extends the existing security hooks
security_inode_removexattr(), security_inode_killpriv(),
security_inode_getsecurity() to pass down the mount's user namespace and
makes them aware of idmapped mounts.

In order to actually get filesystem capabilities from disk the
capability infrastructure exposes the get_vfs_caps_from_disk() helper.
For user namespace aware filesystem capabilities a root uid is stored
alongside the capabilities.

In order to determine whether the caller can make use of the filesystem
capability or whether it needs to be ignored it is translated according
to the superblock's user namespace. If it can be translated to uid 0
according to that id mapping the caller can use the filesystem
capabilities stored on disk. If we are accessing the inode that holds
the filesystem capabilities through an idmapped mount we map the root
uid according to the mount's user namespace. Afterwards the checks are
identical to non-idmapped mounts: reading filesystem caps from disk
enforces that the root uid associated with the filesystem capability
must have a mapping in the superblock's user namespace and that the
caller is either in the same user namespace or is a descendant of the
superblock's user namespace. For filesystems that are mountable inside
user namespace the caller can just mount the filesystem and won't
usually need to idmap it. If they do want to idmap it they can create an
idmapped mount and mark it with a user namespace they created and which
is thus a descendant of s_user_ns. For filesystems that are not
mountable inside user namespaces the descendant rule is trivially true
because the s_user_ns will be the initial user namespace.

If the initial user namespace is passed nothing changes so non-idmapped
mounts will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-11-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christian Brauner 21cb47be6f
inode: make init and permission helpers idmapped mount aware
The inode_owner_or_capable() helper determines whether the caller is the
owner of the inode or is capable with respect to that inode. Allow it to
handle idmapped mounts. If the inode is accessed through an idmapped
mount it according to the mount's user namespace. Afterwards the checks
are identical to non-idmapped mounts. If the initial user namespace is
passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Similarly, allow the inode_init_owner() helper to handle idmapped
mounts. It initializes a new inode on idmapped mounts by mapping the
fsuid and fsgid of the caller from the mount's user namespace. If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-7-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Christian Brauner 47291baa8d
namei: make permission helpers idmapped mount aware
The two helpers inode_permission() and generic_permission() are used by
the vfs to perform basic permission checking by verifying that the
caller is privileged over an inode. In order to handle idmapped mounts
we extend the two helpers with an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode
according to the mount's user namespace and then peform identical
permission checks to inode_permission() and generic_permission(). If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Christian Brauner 0558c1bf5a
capability: handle idmapped mounts
In order to determine whether a caller holds privilege over a given
inode the capability framework exposes the two helpers
privileged_wrt_inode_uidgid() and capable_wrt_inode_uidgid(). The former
verifies that the inode has a mapping in the caller's user namespace and
the latter additionally verifies that the caller has the requested
capability in their current user namespace.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped inodes. If the initial user namespace is passed all
operations are a nop so non-idmapped mounts will not see a change in
behavior.

Link: https://lore.kernel.org/r/20210121131959.646623-5-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Christian Brauner 02f92b3868
fs: add file and path permissions helpers
Add two simple helpers to check permissions on a file and path
respectively and convert over some callers. It simplifies quite a few
codepaths and also reduces the churn in later patches quite a bit.
Christoph also correctly points out that this makes codepaths (e.g.
ioctls) way easier to follow that would otherwise have to do more
complex argument passing than necessary.

Link: https://lore.kernel.org/r/20210121131959.646623-4-christian.brauner@ubuntu.com
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Paul E. McKenney 0d2460ba61 Merge branches 'doc.2021.01.06a', 'fixes.2021.01.04b', 'kfree_rcu.2021.01.04a', 'mmdumpobj.2021.01.22a', 'nocb.2021.01.06a', 'rt.2021.01.04a', 'stall.2021.01.06a', 'torture.2021.01.12a' and 'tortureall.2021.01.06a' into HEAD
doc.2021.01.06a: Documentation updates.
fixes.2021.01.04b: Miscellaneous fixes.
kfree_rcu.2021.01.04a: kfree_rcu() updates.
mmdumpobj.2021.01.22a: Dump allocation point for memory blocks.
nocb.2021.01.06a: RCU callback offload updates and cblist segment lengths.
rt.2021.01.04a: Real-time updates.
stall.2021.01.06a: RCU CPU stall warning updates.
torture.2021.01.12a: Torture-test updates and polling SRCU grace-period API.
tortureall.2021.01.06a: Torture-test script updates.
2021-01-22 15:26:44 -08:00
Paul E. McKenney b4b7914a6a rcu: Make call_rcu() print mem_dump_obj() info for double-freed callback
The debug-object double-free checks in __call_rcu() print out the
RCU callback function, which is usually sufficient to track down the
double free.  However, all uses of things like queue_rcu_work() will
have the same RCU callback function (rcu_work_rcufn() in this case),
so a diagnostic message for a double queue_rcu_work() needs more than
just the callback function.

This commit therefore calls mem_dump_obj() to dump out any additional
available information on the double-freed callback.

Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <linux-mm@kvack.org>
Reported-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-01-22 15:24:16 -08:00
Tobias Klauser 18b24d78d5 bpf: Fix typo in scalar{,32}_min_max_rsh comments
s/bounts/bounds/

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210121174324.24127-1-tklauser@distanz.ch
2021-01-23 00:23:23 +01:00
Pan Bian b9557caaf8 bpf, inode_storage: Put file handler if no storage was found
Put file f if inode_storage_ptr() returns NULL.

Fixes: 8ea636848a ("bpf: Implement bpf_local_storage for inodes")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210121020856.25507-1-bianpan2016@163.com
2021-01-22 23:19:24 +01:00
Loris Reiff f4a2da755a bpf, cgroup: Fix problematic bounds check
Since ctx.optlen is signed, a larger value than max_value could be
passed, as it is later on used as unsigned, which causes a WARN_ON_ONCE
in the copy_to_user.

Fixes: 0d01da6afc ("bpf: implement getsockopt and setsockopt hooks")
Signed-off-by: Loris Reiff <loris.reiff@liblor.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20210122164232.61770-2-loris.reiff@liblor.ch
2021-01-22 23:11:47 +01:00
Loris Reiff bb8b81e396 bpf, cgroup: Fix optlen WARN_ON_ONCE toctou
A toctou issue in `__cgroup_bpf_run_filter_getsockopt` can trigger a
WARN_ON_ONCE in a check of `copy_from_user`.

`*optlen` is checked to be non-negative in the individual getsockopt
functions beforehand. Changing `*optlen` in a race to a negative value
will result in a `copy_from_user(ctx.optval, optval, ctx.optlen)` with
`ctx.optlen` being a negative integer.

Fixes: 0d01da6afc ("bpf: implement getsockopt and setsockopt hooks")
Signed-off-by: Loris Reiff <loris.reiff@liblor.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20210122164232.61770-1-loris.reiff@liblor.ch
2021-01-22 23:11:34 +01:00
Peter Zijlstra 741ba80f6f sched: Relax the set_cpus_allowed_ptr() semantics
Now that we have KTHREAD_IS_PER_CPU to denote the critical per-cpu
tasks to retain during CPU offline, we can relax the warning in
set_cpus_allowed_ptr(). Any spurious kthread that wants to get on at
the last minute will get pushed off before it can run.

While during CPU online there is no harm, and actual benefit, to
allowing kthreads back on early, it simplifies hotplug code and fixes
a number of outstanding races.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Lai jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103507.240724591@infradead.org
2021-01-22 15:09:44 +01:00
Peter Zijlstra 5ba2ffba13 sched: Fix CPU hotplug / tighten is_per_cpu_kthread()
Prior to commit 1cf12e08bc ("sched/hotplug: Consolidate task
migration on CPU unplug") we'd leave any task on the dying CPU and
break affinity and force them off at the very end.

This scheme had to change in order to enable migrate_disable(). One
cannot wait for migrate_disable() to complete while stuck in
stop_machine(). Furthermore, since we need at the very least: idle,
hotplug and stop threads at any point before stop_machine, we can't
break affinity and/or push those away.

Under the assumption that all per-cpu kthreads are sanely handled by
CPU hotplug, the new code no long breaks affinity or migrates any of
them (which then includes the critical ones above).

However, there's an important difference between per-cpu kthreads and
kthreads that happen to have a single CPU affinity which is lost. The
latter class very much relies on the forced affinity breaking and
migration semantics previously provided.

Use the new kthread_is_per_cpu() infrastructure to tighten
is_per_cpu_kthread() and fix the hot-unplug problems stemming from the
change.

Fixes: 1cf12e08bc ("sched/hotplug: Consolidate task migration on CPU unplug")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103507.102416009@infradead.org
2021-01-22 15:09:44 +01:00
Peter Zijlstra 975707f227 sched: Prepare to use balance_push in ttwu()
In preparation of using the balance_push state in ttwu() we need it to
provide a reliable and consistent state.

The immediate problem is that rq->balance_callback gets cleared every
schedule() and then re-set in the balance_push_callback() itself. This
is not a reliable signal, so add a variable that stays set during the
entire time.

Also move setting it before the synchronize_rcu() in
sched_cpu_deactivate(), such that we get guaranteed visibility to
ttwu(), which is a preempt-disable region.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.966069627@infradead.org
2021-01-22 15:09:43 +01:00
Peter Zijlstra 640f17c824 workqueue: Restrict affinity change to rescuer
create_worker() will already set the right affinity using
kthread_bind_mask(), this means only the rescuer will need to change
it's affinity.

Howveer, while in cpu-hot-unplug a regular task is not allowed to run
on online&&!active as it would be pushed away quite agressively. We
need KTHREAD_IS_PER_CPU to survive in that environment.

Therefore set the affinity after getting that magic flag.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.826629830@infradead.org
2021-01-22 15:09:43 +01:00
Peter Zijlstra 5c25b5ff89 workqueue: Tag bound workers with KTHREAD_IS_PER_CPU
Mark the per-cpu workqueue workers as KTHREAD_IS_PER_CPU.

Workqueues have unfortunate semantics in that per-cpu workers are not
default flushed and parked during hotplug, however a subset does
manual flush on hotplug and hard relies on them for correctness.

Therefore play silly games..

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.693465814@infradead.org
2021-01-22 15:09:42 +01:00
Peter Zijlstra ac687e6e8c kthread: Extract KTHREAD_IS_PER_CPU
There is a need to distinguish geniune per-cpu kthreads from kthreads
that happen to have a single CPU affinity.

Geniune per-cpu kthreads are kthreads that are CPU affine for
correctness, these will obviously have PF_KTHREAD set, but must also
have PF_NO_SETAFFINITY set, lest userspace modify their affinity and
ruins things.

However, these two things are not sufficient, PF_NO_SETAFFINITY is
also set on other tasks that have their affinities controlled through
other means, like for instance workqueues.

Therefore another bit is needed; it turns out kthread_create_per_cpu()
already has such a bit: KTHREAD_IS_PER_CPU, which is used to make
kthread_park()/kthread_unpark() work correctly.

Expose this flag and remove the implicit setting of it from
kthread_create_on_cpu(); the io_uring usage of it seems dubious at
best.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.557620262@infradead.org
2021-01-22 15:09:42 +01:00
Peter Zijlstra 22f667c97a sched: Don't run cpu-online with balance_push() enabled
We don't need to push away tasks when we come online, mark the push
complete right before the CPU dies.

XXX hotplug state machine has trouble with rollback here.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.415606087@infradead.org
2021-01-22 15:09:42 +01:00
Lai Jiangshan 547a77d02f workqueue: Use cpu_possible_mask instead of cpu_active_mask to break affinity
The scheduler won't break affinity for us any more, and we should
"emulate" the same behavior when the scheduler breaks affinity for
us.  The behavior is "changing the cpumask to cpu_possible_mask".

And there might be some other CPUs online later while the worker is
still running with the pending work items.  The worker should be allowed
to use the later online CPUs as before and process the work items ASAP.
If we use cpu_active_mask here, we can't achieve this goal but
using cpu_possible_mask can.

Fixes: 06249738a4 ("workqueue: Manually break affinity on hotplug")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210111152638.2417-4-jiangshanlai@gmail.com
2021-01-22 15:09:41 +01:00
Valentin Schneider 36c6e17bf1 sched/core: Print out straggler tasks in sched_cpu_dying()
Since commit

  1cf12e08bc ("sched/hotplug: Consolidate task migration on CPU unplug")

tasks are expected to move themselves out of a out-going CPU. For most
tasks this will be done automagically via BALANCE_PUSH, but percpu kthreads
will have to cooperate and move themselves away one way or another.

Currently, some percpu kthreads (workqueues being a notable exemple) do not
cooperate nicely and can end up on an out-going CPU at the time
sched_cpu_dying() is invoked.

Print the dying rq's tasks to shed some light on the stragglers.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210113183141.11974-1-valentin.schneider@arm.com
2021-01-22 15:09:41 +01:00
Mark Rutland 997acaf6b4 lockdep: report broken irq restoration
We generally expect local_irq_save() and local_irq_restore() to be
paired and sanely nested, and so local_irq_restore() expects to be
called with irqs disabled. Thus, within local_irq_restore() we only
trace irq flag changes when unmasking irqs.

This means that a sequence such as:

| local_irq_disable();
| local_irq_save(flags);
| local_irq_enable();
| local_irq_restore(flags);

... is liable to break things, as the local_irq_restore() would mask
irqs without tracing this change. Similar problems may exist for
architectures whose arch_irq_restore() function depends on being called
with irqs disabled.

We don't consider such sequences to be a good idea, so let's define
those as forbidden, and add tooling to detect such broken cases.

This patch adds debug code to WARN() when raw_local_irq_restore() is
called with irqs enabled. As raw_local_irq_restore() is expected to pair
with raw_local_irq_save(), it should never be called with irqs enabled.

To avoid the possibility of circular header dependencies between
irqflags.h and bug.h, the warning is handled in a separate C file.

The new code is all conditional on a new CONFIG_DEBUG_IRQFLAGS symbol
which is independent of CONFIG_TRACE_IRQFLAGS. As noted above such cases
will confuse lockdep, so CONFIG_DEBUG_LOCKDEP now selects
CONFIG_DEBUG_IRQFLAGS.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210111153707.10071-1-mark.rutland@arm.com
2021-01-22 11:08:56 +01:00
Linus Torvalds 2561bbbe2e Printk fixes for 5.11-rc5
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Merge tag 'printk-for-5.11-printk-rework-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk fixes from Petr Mladek:

 - Fix line counting and buffer size calculation. Both regressions
   caused that a reader buffer might not get filled as much as possible.

 - Restore non-documented behavior of printk() reader API and make it
   official.

   It did not fill the last byte of the provided buffer before 5.10. Two
   architectures, powerpc and um, used it to add the trailing '\0'.
   There might theoretically be more callers depending on this behavior
   in userspace.

* tag 'printk-for-5.11-printk-rework-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: fix buffer overflow potential for print_text()
  printk: fix kmsg_dump_get_buffer length calulations
  printk: ringbuffer: fix line counting
2021-01-21 11:37:22 -08:00
Petr Mladek 535b6a122c Merge branch 'printk-rework' into for-linus 2021-01-21 16:06:21 +01:00
Stanislav Fomichev a9ed15dae0 bpf: Split cgroup_bpf_enabled per attach type
When we attach any cgroup hook, the rest (even if unused/unattached) start
to contribute small overhead. In particular, the one we want to avoid is
__cgroup_bpf_run_filter_skb which does two redirections to get to
the cgroup and pushes/pulls skb.

Let's split cgroup_bpf_enabled to be per-attach to make sure
only used attach types trigger.

I've dropped some existing high-level cgroup_bpf_enabled in some
places because BPF_PROG_CGROUP_XXX_RUN macros usually have another
cgroup_bpf_enabled check.

I also had to copy-paste BPF_CGROUP_RUN_SA_PROG_LOCK for
GETPEERNAME/GETSOCKNAME because type for cgroup_bpf_enabled[type]
has to be constant and known at compile time.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-4-sdf@google.com
2021-01-20 14:23:00 -08:00
Stanislav Fomichev 20f2505fb4 bpf: Try to avoid kzalloc in cgroup/{s,g}etsockopt
When we attach a bpf program to cgroup/getsockopt any other getsockopt()
syscall starts incurring kzalloc/kfree cost.

Let add a small buffer on the stack and use it for small (majority)
{s,g}etsockopt values. The buffer is small enough to fit into
the cache line and cover the majority of simple options (most
of them are 4 byte ints).

It seems natural to do the same for setsockopt, but it's a bit more
involved when the BPF program modifies the data (where we have to
kmalloc). The assumption is that for the majority of setsockopt
calls (which are doing pure BPF options or apply policy) this
will bring some benefit as well.

Without this patch (we remove about 1% __kmalloc):
     3.38%     0.07%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt
            |
             --3.30%--__cgroup_bpf_run_filter_getsockopt
                       |
                        --0.81%--__kmalloc

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-3-sdf@google.com
2021-01-20 14:23:00 -08:00
Stanislav Fomichev 9cacf81f81 bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE
Add custom implementation of getsockopt hook for TCP_ZEROCOPY_RECEIVE.
We skip generic hooks for TCP_ZEROCOPY_RECEIVE and have a custom
call in do_tcp_getsockopt using the on-stack data. This removes
3% overhead for locking/unlocking the socket.

Without this patch:
     3.38%     0.07%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt
            |
             --3.30%--__cgroup_bpf_run_filter_getsockopt
                       |
                        --0.81%--__kmalloc

With the patch applied:
     0.52%     0.12%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt_kern

Note, exporting uapi/tcp.h requires removing netinet/tcp.h
from test_progs.h because those headers have confliciting
definitions.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-2-sdf@google.com
2021-01-20 14:23:00 -08:00
Yonghong Song 13ca51d5eb bpf: Permit size-0 datasec
llvm patch https://reviews.llvm.org/D84002 permitted
to emit empty rodata datasec if the elf .rodata section
contains read-only data from local variables. These
local variables will be not emitted as BTF_KIND_VARs
since llvm converted these local variables as
static variables with private linkage without debuginfo
types. Such an empty rodata datasec will make
skeleton code generation easy since for skeleton
a rodata struct will be generated if there is a
.rodata elf section. The existence of a rodata
btf datasec is also consistent with the existence
of a rodata map created by libbpf.

The btf with such an empty rodata datasec will fail
in the kernel though as kernel will reject a datasec
with zero vlen and zero size. For example, for the below code,
    int sys_enter(void *ctx)
    {
       int fmt[6] = {1, 2, 3, 4, 5, 6};
       int dst[6];

       bpf_probe_read(dst, sizeof(dst), fmt);
       return 0;
    }
We got the below btf (bpftool btf dump ./test.o):
    [1] PTR '(anon)' type_id=0
    [2] FUNC_PROTO '(anon)' ret_type_id=3 vlen=1
            'ctx' type_id=1
    [3] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED
    [4] FUNC 'sys_enter' type_id=2 linkage=global
    [5] INT 'char' size=1 bits_offset=0 nr_bits=8 encoding=SIGNED
    [6] ARRAY '(anon)' type_id=5 index_type_id=7 nr_elems=4
    [7] INT '__ARRAY_SIZE_TYPE__' size=4 bits_offset=0 nr_bits=32 encoding=(none)
    [8] VAR '_license' type_id=6, linkage=global-alloc
    [9] DATASEC '.rodata' size=0 vlen=0
    [10] DATASEC 'license' size=0 vlen=1
            type_id=8 offset=0 size=4
When loading the ./test.o to the kernel with bpftool,
we see the following error:
    libbpf: Error loading BTF: Invalid argument(22)
    libbpf: magic: 0xeb9f
    ...
    [6] ARRAY (anon) type_id=5 index_type_id=7 nr_elems=4
    [7] INT __ARRAY_SIZE_TYPE__ size=4 bits_offset=0 nr_bits=32 encoding=(none)
    [8] VAR _license type_id=6 linkage=1
    [9] DATASEC .rodata size=24 vlen=0 vlen == 0
    libbpf: Error loading .BTF into kernel: -22. BTF is optional, ignoring.

Basically, libbpf changed .rodata datasec size to 24 since elf .rodata
section size is 24. The kernel then rejected the BTF since vlen = 0.
Note that the above kernel verifier failure can be worked around with
changing local variable "fmt" to a static or global, optionally const, variable.

This patch permits a datasec with vlen = 0 in kernel.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210119153519.3901963-1-yhs@fb.com
2021-01-20 14:14:09 -08:00
Lorenzo Bianconi 97a0e1ea7b net, xdp: Introduce __xdp_build_skb_from_frame utility routine
Introduce __xdp_build_skb_from_frame utility routine to build
the skb from xdp_frame. Rely on __xdp_build_skb_from_frame in
cpumap code.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/4f9f4c6b3dd3933770c617eb6689dbc0c6e25863.1610475660.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-01-20 14:10:35 -08:00
Jakub Kicinski 0fe2f273ab Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

drivers/net/can/dev.c
  commit 03f16c5075 ("can: dev: can_restart: fix use after free bug")
  commit 3e77f70e73 ("can: dev: move driver related infrastructure into separate subdir")

  Code move.

drivers/net/dsa/b53/b53_common.c
 commit 8e4052c32d ("net: dsa: b53: fix an off by one in checking "vlan->vid"")
 commit b7a9e0da2d ("net: switchdev: remove vid_begin -> vid_end range from VLAN objects")

 Field rename.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-20 12:16:11 -08:00
Linus Torvalds 75439bc439 Networking fixes for 5.11-rc5, including fixes from bpf, wireless,
and can trees.
 
 Current release - regressions:
 
  - nfc: nci: fix the wrong NCI_CORE_INIT parameters
 
 Current release - new code bugs:
 
  - bpf: allow empty module BTFs
 
 Previous releases - regressions:
 
  - bpf: fix signed_{sub,add32}_overflows type handling
 
  - tcp: do not mess with cloned skbs in tcp_add_backlog()
 
  - bpf: prevent double bpf_prog_put call from bpf_tracing_prog_attach
 
  - bpf: don't leak memory in bpf getsockopt when optlen == 0
 
  - tcp: fix potential use-after-free due to double kfree()
 
  - mac80211: fix encryption issues with WEP
 
  - devlink: use right genl user_ptr when handling port param get/set
 
  - ipv6: set multicast flag on the multicast route
 
  - tcp: fix TCP_USER_TIMEOUT with zero window
 
 Previous releases - always broken:
 
  - bpf: local storage helpers should check nullness of owner ptr passed
 
  - mac80211: fix incorrect strlen of .write in debugfs
 
  - cls_flower: call nla_ok() before nla_next()
 
  - skbuff: back tiny skbs with kmalloc() in __netdev_alloc_skb() too
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.11-rc5, including fixes from bpf, wireless, and
  can trees.

  Current release - regressions:

   - nfc: nci: fix the wrong NCI_CORE_INIT parameters

  Current release - new code bugs:

   - bpf: allow empty module BTFs

  Previous releases - regressions:

   - bpf: fix signed_{sub,add32}_overflows type handling

   - tcp: do not mess with cloned skbs in tcp_add_backlog()

   - bpf: prevent double bpf_prog_put call from bpf_tracing_prog_attach

   - bpf: don't leak memory in bpf getsockopt when optlen == 0

   - tcp: fix potential use-after-free due to double kfree()

   - mac80211: fix encryption issues with WEP

   - devlink: use right genl user_ptr when handling port param get/set

   - ipv6: set multicast flag on the multicast route

   - tcp: fix TCP_USER_TIMEOUT with zero window

  Previous releases - always broken:

   - bpf: local storage helpers should check nullness of owner ptr passed

   - mac80211: fix incorrect strlen of .write in debugfs

   - cls_flower: call nla_ok() before nla_next()

   - skbuff: back tiny skbs with kmalloc() in __netdev_alloc_skb() too"

* tag 'net-5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (52 commits)
  net: systemport: free dev before on error path
  net: usb: cdc_ncm: don't spew notifications
  net: mscc: ocelot: Fix multicast to the CPU port
  tcp: Fix potential use-after-free due to double kfree()
  bpf: Fix signed_{sub,add32}_overflows type handling
  can: peak_usb: fix use after free bugs
  can: vxcan: vxcan_xmit: fix use after free bug
  can: dev: can_restart: fix use after free bug
  tcp: fix TCP socket rehash stats mis-accounting
  net: dsa: b53: fix an off by one in checking "vlan->vid"
  tcp: do not mess with cloned skbs in tcp_add_backlog()
  selftests: net: fib_tests: remove duplicate log test
  net: nfc: nci: fix the wrong NCI_CORE_INIT parameters
  sh_eth: Fix power down vs. is_opened flag ordering
  net: Disable NETIF_F_HW_TLS_RX when RXCSUM is disabled
  netfilter: rpfilter: mask ecn bits before fib lookup
  udp: mask TOS bits in udp_v4_early_demux()
  xsk: Clear pool even for inactive queues
  bpf: Fix helper bpf_map_peek_elem_proto pointing to wrong callback
  sh_eth: Make PHY access aware of Runtime PM to fix reboot crash
  ...
2021-01-20 11:52:21 -08:00
Daniel Borkmann bc895e8b2a bpf: Fix signed_{sub,add32}_overflows type handling
Fix incorrect signed_{sub,add32}_overflows() input types (and a related buggy
comment). It looks like this might have slipped in via copy/paste issue, also
given prior to 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
the signature of signed_sub_overflows() had s64 a and s64 b as its input args
whereas now they are truncated to s32. Thus restore proper types. Also, the case
of signed_add32_overflows() is not consistent to signed_sub32_overflows(). Both
have s32 as inputs, therefore align the former.

Fixes: 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Reported-by: De4dCr0w <sa516203@mail.ustc.edu.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-01-20 17:19:40 +01:00
Linus Torvalds 45dfb8a565 task_work-2021-01-19
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Merge tag 'task_work-2021-01-19' of git://git.kernel.dk/linux-block

Pull task_work fix from Jens Axboe:
 "The TIF_NOTIFY_SIGNAL change inadvertently removed the unconditional
  task_work run we had in get_signal().

  This caused a regression for some setups, since we're relying on eg
  ____fput() being run to close and release, for example, a pipe and
  wake the other end.

  For 5.11, I prefer the simple solution of just reinstating the
  unconditional run, even if it conceptually doesn't make much sense -
  if you need that kind of guarantee, you should be using TWA_SIGNAL
  instead of TWA_NOTIFY. But it's the trivial fix for 5.11, and would
  ensure that other potential gotchas/assumptions for task_work don't
  regress for 5.11.

  We're looking into further simplifying the task_work notifications for
  5.12 which would resolve that too"

* tag 'task_work-2021-01-19' of git://git.kernel.dk/linux-block:
  task_work: unconditionally run task_work from get_signal()
2021-01-19 13:26:05 -08:00
Mircea Cirjaliu 301a33d518 bpf: Fix helper bpf_map_peek_elem_proto pointing to wrong callback
I assume this was obtained by copy/paste. Point it to bpf_map_peek_elem()
instead of bpf_map_pop_elem(). In practice it may have been less likely
hit when under JIT given shielded via 84430d4232 ("bpf, verifier: avoid
retpoline for map push/pop/peek operation").

Fixes: f1a2e44a3a ("bpf: add queue and stack maps")
Signed-off-by: Mircea Cirjaliu <mcirjaliu@bitdefender.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Mauricio Vasquez <mauriciovasquezbernal@gmail.com>
Link: https://lore.kernel.org/bpf/AM7PR02MB6082663DFDCCE8DA7A6DD6B1BBA30@AM7PR02MB6082.eurprd02.prod.outlook.com
2021-01-19 22:04:08 +01:00
Odin Ugedal 385aac1519 cgroup: fix psi monitor for root cgroup
Fix NULL pointer dereference when adding new psi monitor to the root
cgroup. PSI files for root cgroup was introduced in df5ba5be74 by using
system wide psi struct when reading, but file write/monitor was not
properly fixed. Since the PSI config for the root cgroup isn't
initialized, the current implementation tries to lock a NULL ptr,
resulting in a crash.

Can be triggered by running this as root:
$ tee /sys/fs/cgroup/cpu.pressure <<< "some 10000 1000000"

Signed-off-by: Odin Ugedal <odin@uged.al>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Dan Schatzberg <dschatzberg@fb.com>
Fixes: df5ba5be74 ("kernel/sched/psi.c: expose pressure metrics on root cgroup")
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: stable@vger.kernel.org # 5.2+
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-19 11:37:05 -05:00
John Ogness f0e386ee0c printk: fix buffer overflow potential for print_text()
Before the commit 896fbe20b4 ("printk: use the lockless
ringbuffer"), msg_print_text() would only write up to size-1 bytes
into the provided buffer. Some callers expect this behavior and
append a terminator to returned string. In particular:

arch/powerpc/xmon/xmon.c:dump_log_buf()
arch/um/kernel/kmsg_dump.c:kmsg_dumper_stdout()

msg_print_text() has been replaced by record_print_text(), which
currently fills the full size of the buffer. This causes a
buffer overflow for the above callers.

Change record_print_text() so that it will only use size-1 bytes
for text data. Also, for paranoia sakes, add a terminator after
the text data.

And finally, document this behavior so that it is clear that only
size-1 bytes are used and a terminator is added.

Fixes: 896fbe20b4 ("printk: use the lockless ringbuffer")
Cc: stable@vger.kernel.org # 5.10+
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210114170412.4819-1-john.ogness@linutronix.de
2021-01-19 11:42:14 +01:00
Frank van der Linden ec2a29593c module: harden ELF info handling
5fdc7db644 ("module: setup load info before module_sig_check()")
moved the ELF setup, so that it was done before the signature
check. This made the module name available to signature error
messages.

However, the checks for ELF correctness in setup_load_info
are not sufficient to prevent bad memory references due to
corrupted offset fields, indices, etc.

So, there's a regression in behavior here: a corrupt and unsigned
(or badly signed) module, which might previously have been rejected
immediately, can now cause an oops/crash.

Harden ELF handling for module loading by doing the following:

- Move the signature check back up so that it comes before ELF
  initialization. It's best to do the signature check to see
  if we can trust the module, before using the ELF structures
  inside it. This also makes checks against info->len
  more accurate again, as this field will be reduced by the
  length of the signature in mod_check_sig().

  The module name is now once again not available for error
  messages during the signature check, but that seems like
  a fair tradeoff.

- Check if sections have offset / size fields that at least don't
  exceed the length of the module.

- Check if sections have section name offsets that don't fall
  outside the section name table.

- Add a few other sanity checks against invalid section indices,
  etc.

This is not an exhaustive consistency check, but the idea is to
at least get through the signature and blacklist checks without
crashing because of corrupted ELF info, and to error out gracefully
for most issues that would have caused problems later on.

Fixes: 5fdc7db644 ("module: setup load info before module_sig_check()")
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-01-19 10:24:45 +01:00
Fangrui Song ebfac7b778 module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbols
clang-12 -fno-pic (since
a084c0388e)
can emit `call __stack_chk_fail@PLT` instead of `call __stack_chk_fail`
on x86.  The two forms should have identical behaviors on x86-64 but the
former causes GNU as<2.37 to produce an unreferenced undefined symbol
_GLOBAL_OFFSET_TABLE_.

(On x86-32, there is an R_386_PC32 vs R_386_PLT32 difference but the
linker behavior is identical as far as Linux kernel is concerned.)

Simply ignore _GLOBAL_OFFSET_TABLE_ for now, like what
scripts/mod/modpost.c:ignore_undef_symbol does. This also fixes the
problem for gcc/clang -fpie and -fpic, which may emit `call foo@PLT` for
external function calls on x86.

Note: ld -z defs and dynamic loaders do not error for unreferenced
undefined symbols so the module loader is reading too much.  If we ever
need to ignore more symbols, the code should be refactored to ignore
unreferenced symbols.

Cc: <stable@vger.kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/1250
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=27178
Reported-by: Marco Elver <elver@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Marco Elver <elver@google.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-01-18 10:45:42 +01:00
Jakub Kicinski 2d9116be76 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2021-01-16

1) Extend atomic operations to the BPF instruction set along with x86-64 JIT support,
   that is, atomic{,64}_{xchg,cmpxchg,fetch_{add,and,or,xor}}, from Brendan Jackman.

2) Add support for using kernel module global variables (__ksym externs in BPF
   programs) retrieved via module's BTF, from Andrii Nakryiko.

3) Generalize BPF stackmap's buildid retrieval and add support to have buildid
   stored in mmap2 event for perf, from Jiri Olsa.

4) Various fixes for cross-building BPF sefltests out-of-tree which then will
   unblock wider automated testing on ARM hardware, from Jean-Philippe Brucker.

5) Allow to retrieve SOL_SOCKET opts from sock_addr progs, from Daniel Borkmann.

6) Clean up driver's XDP buffer init and split into two helpers to init per-
   descriptor and non-changing fields during processing, from Lorenzo Bianconi.

7) Minor misc improvements to libbpf & bpftool, from Ian Rogers.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (41 commits)
  perf: Add build id data in mmap2 event
  bpf: Add size arg to build_id_parse function
  bpf: Move stack_map_get_build_id into lib
  bpf: Document new atomic instructions
  bpf: Add tests for new BPF atomic operations
  bpf: Add bitwise atomic instructions
  bpf: Pull out a macro for interpreting atomic ALU operations
  bpf: Add instructions for atomic_[cmp]xchg
  bpf: Add BPF_FETCH field / create atomic_fetch_add instruction
  bpf: Move BPF_STX reserved field check into BPF_STX verifier code
  bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
  bpf: x86: Factor out a lookup table for some ALU opcodes
  bpf: x86: Factor out emission of REX byte
  bpf: x86: Factor out emission of ModR/M for *(reg + off)
  tools/bpftool: Add -Wall when building BPF programs
  bpf, libbpf: Avoid unused function warning on bpf_tail_call_static
  selftests/bpf: Install btf_dump test cases
  selftests/bpf: Fix installation of urandom_read
  selftests/bpf: Move generated test files to $(TEST_GEN_FILES)
  selftests/bpf: Fix out-of-tree build
  ...
====================

Link: https://lore.kernel.org/r/20210116012922.17823-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15 17:57:26 -08:00
Jakub Kicinski e23a8d0021 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2021-01-16

1) Fix a double bpf_prog_put() for BPF_PROG_{TYPE_EXT,TYPE_TRACING} types in
   link creation's error path causing a refcount underflow, from Jiri Olsa.

2) Fix BTF validation errors for the case where kernel modules don't declare
   any new types and end up with an empty BTF, from Andrii Nakryiko.

3) Fix BPF local storage helpers to first check their {task,inode} owners for
   being NULL before access, from KP Singh.

4) Fix a memory leak in BPF setsockopt handling for the case where optlen is
   zero and thus temporary optval buffer should be freed, from Stanislav Fomichev.

5) Fix a syzbot memory allocation splat in BPF_PROG_TEST_RUN infra for
   raw_tracepoint caused by too big ctx_size_in, from Song Liu.

6) Fix LLVM code generation issues with verifier where PTR_TO_MEM{,_OR_NULL}
   registers were spilled to stack but not recognized, from Gilad Reti.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  MAINTAINERS: Update my email address
  selftests/bpf: Add verifier test for PTR_TO_MEM spill
  bpf: Support PTR_TO_MEM{,_OR_NULL} register spilling
  bpf: Reject too big ctx_size_in for raw_tp test run
  libbpf: Allow loading empty BTFs
  bpf: Allow empty module BTFs
  bpf: Don't leak memory in bpf getsockopt when optlen == 0
  bpf: Update local storage test to check handling of null ptrs
  bpf: Fix typo in bpf_inode_storage.c
  bpf: Local storage helpers should check nullness of owner ptr passed
  bpf: Prevent double bpf_prog_put call from bpf_tracing_prog_attach
====================

Link: https://lore.kernel.org/r/20210116002025.15706-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15 16:34:59 -08:00
Aubrey Li 415de5fdeb cpuset: fix typos in comments
Change hierachy to hierarchy and congifured to configured, no functionality
changed.

Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-15 15:36:41 -05:00
Michal Koutný da70862efe cgroup: cgroup.{procs,threads} factor out common parts
The functions cgroup_threads_write and cgroup_procs_write are almost
identical. In order to reduce duplication, factor out the common code in
similar fashion we already do for other threadgroup/task functions. No
functional changes are intended.

Suggested-by: Hao Lee <haolee.swjtu@gmail.com>
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-15 15:36:18 -05:00
Chen Zhou 61e960b07b cgroup-v1: add disabled controller check in cgroup1_parse_param()
When mounting a cgroup hierarchy with disabled controller in cgroup v1,
all available controllers will be attached.
For example, boot with cgroup_no_v1=cpu or cgroup_disable=cpu, and then
mount with "mount -t cgroup -ocpu cpu /sys/fs/cgroup/cpu", then all
enabled controllers will be attached except cpu.

Fix this by adding disabled controller check in cgroup1_parse_param().
If the specified controller is disabled, just return error with information
"Disabled controller xx" rather than attaching all the other enabled
controllers.

Fixes: f5dfb5315d ("cgroup: take options parsing into ->parse_monolithic()")
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Reviewed-by: Zefan Li <lizefan.x@bytedance.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-15 15:10:37 -05:00
Davidlohr Bueso c1de44631e audit: Remove leftover reference to the audit_tasklet
This was replaced with a kauditd_wait kthread long ago,
back in:

     b7d1125817 (AUDIT: Send netlink messages from a separate kernel thread)

Update the stale comment.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-01-15 11:58:10 -05:00
John Ogness 89ccf18f03 printk: fix kmsg_dump_get_buffer length calulations
kmsg_dump_get_buffer() uses @syslog to determine if the syslog
prefix should be written to the buffer. However, when calculating
the maximum number of records that can fit into the buffer, it
always counts the bytes from the syslog prefix.

Use @syslog when calculating the maximum number of records that can
fit into the buffer.

Fixes: e2ae715d66 ("kmsg - kmsg_dump() use iterator to receive log buffer content")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210113164413.1599-1-john.ogness@linutronix.de
2021-01-15 11:32:52 +01:00
John Ogness 668af87f99 printk: ringbuffer: fix line counting
Counting text lines in a record simply involves counting the number
of newline characters (+1). However, it is searching the full data
block for newline characters, even though the text data can be (and
often is) a subset of that area. Since the extra area in the data
block was never initialized, the result is that extra newlines may
be seen and counted.

Restrict newline searching to the text data length.

Fixes: b6cf8b3f33 ("printk: add lockless ringbuffer")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210113144234.6545-1-john.ogness@linutronix.de
2021-01-15 11:30:03 +01:00
Jiri Olsa 88a16a1309 perf: Add build id data in mmap2 event
Adding support to carry build id data in mmap2 event.

The build id data replaces maj/min/ino/ino_generation
fields, which are also used to identify map's binary,
so it's ok to replace them with build id data:

  union {
          struct {
                  u32       maj;
                  u32       min;
                  u64       ino;
                  u64       ino_generation;
          };
          struct {
                  u8        build_id_size;
                  u8        __reserved_1;
                  u16       __reserved_2;
                  u8        build_id[20];
          };
  };

Replaced maj/min/ino/ino_generation fields give us size
of 24 bytes. We use 20 bytes for build id data, 1 byte
for size and rest is unused.

There's new misc bit for mmap2 to signal there's build
id data in it:

  #define PERF_RECORD_MISC_MMAP_BUILD_ID   (1 << 14)

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/bpf/20210114134044.1418404-4-jolsa@kernel.org
2021-01-14 19:29:58 -08:00
Jiri Olsa 921f88fc89 bpf: Add size arg to build_id_parse function
It's possible to have other build id types (other than default SHA1).
Currently there's also ld support for MD5 build id.

Adding size argument to build_id_parse function, that returns (if defined)
size of the parsed build id, so we can recognize the build id type.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210114134044.1418404-3-jolsa@kernel.org
2021-01-14 19:29:58 -08:00
Jiri Olsa bd7525dacd bpf: Move stack_map_get_build_id into lib
Moving stack_map_get_build_id into lib with
declaration in linux/buildid.h header:

  int build_id_parse(struct vm_area_struct *vma, unsigned char *build_id);

This function returns build id for given struct vm_area_struct.
There is no functional change to stack_map_get_build_id function.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210114134044.1418404-2-jolsa@kernel.org
2021-01-14 19:29:58 -08:00
Brendan Jackman 981f94c3e9 bpf: Add bitwise atomic instructions
This adds instructions for

atomic[64]_[fetch_]and
atomic[64]_[fetch_]or
atomic[64]_[fetch_]xor

All these operations are isomorphic enough to implement with the same
verifier, interpreter, and x86 JIT code, hence being a single commit.

The main interesting thing here is that x86 doesn't directly support
the fetch_ version these operations, so we need to generate a CMPXCHG
loop in the JIT. This requires the use of two temporary registers,
IIUC it's safe to use BPF_REG_AX and x86's AUX_REG for this purpose.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-10-jackmanb@google.com
2021-01-14 18:34:29 -08:00
Brendan Jackman 462910670e bpf: Pull out a macro for interpreting atomic ALU operations
Since the atomic operations that are added in subsequent commits are
all isomorphic with BPF_ADD, pull out a macro to avoid the
interpreter becoming dominated by lines of atomic-related code.

Note that this sacrificies interpreter performance (combining
STX_ATOMIC_W and STX_ATOMIC_DW into single switch case means that we
need an extra conditional branch to differentiate them) in favour of
compact and (relatively!) simple C code.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-9-jackmanb@google.com
2021-01-14 18:34:29 -08:00
Brendan Jackman 5ffa25502b bpf: Add instructions for atomic_[cmp]xchg
This adds two atomic opcodes, both of which include the BPF_FETCH
flag. XCHG without the BPF_FETCH flag would naturally encode
atomic_set. This is not supported because it would be of limited
value to userspace (it doesn't imply any barriers). CMPXCHG without
BPF_FETCH woulud be an atomic compare-and-write. We don't have such
an operation in the kernel so it isn't provided to BPF either.

There are two significant design decisions made for the CMPXCHG
instruction:

 - To solve the issue that this operation fundamentally has 3
   operands, but we only have two register fields. Therefore the
   operand we compare against (the kernel's API calls it 'old') is
   hard-coded to be R0. x86 has similar design (and A64 doesn't
   have this problem).

   A potential alternative might be to encode the other operand's
   register number in the immediate field.

 - The kernel's atomic_cmpxchg returns the old value, while the C11
   userspace APIs return a boolean indicating the comparison
   result. Which should BPF do? A64 returns the old value. x86 returns
   the old value in the hard-coded register (and also sets a
   flag). That means return-old-value is easier to JIT, so that's
   what we use.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-8-jackmanb@google.com
2021-01-14 18:34:29 -08:00
Brendan Jackman 5ca419f286 bpf: Add BPF_FETCH field / create atomic_fetch_add instruction
The BPF_FETCH field can be set in bpf_insn.imm, for BPF_ATOMIC
instructions, in order to have the previous value of the
atomically-modified memory location loaded into the src register
after an atomic op is carried out.

Suggested-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-7-jackmanb@google.com
2021-01-14 18:34:29 -08:00
Brendan Jackman c5bcb5eb4d bpf: Move BPF_STX reserved field check into BPF_STX verifier code
I can't find a reason why this code is in resolve_pseudo_ldimm64;
since I'll be modifying it in a subsequent commit, tidy it up.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-6-jackmanb@google.com
2021-01-14 18:34:29 -08:00
Brendan Jackman 91c960b005 bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
A subsequent patch will add additional atomic operations. These new
operations will use the same opcode field as the existing XADD, with
the immediate discriminating different operations.

In preparation, rename the instruction mode BPF_ATOMIC and start
calling the zero immediate BPF_ADD.

This is possible (doesn't break existing valid BPF progs) because the
immediate field is currently reserved MBZ and BPF_ADD is zero.

All uses are removed from the tree but the BPF_XADD definition is
kept around to avoid breaking builds for people including kernel
headers.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com
2021-01-14 18:34:29 -08:00
Boqun Feng 5f2962401c locking/lockdep: Exclude local_lock_t from IRQ inversions
The purpose of local_lock_t is to abstract: preempt_disable() /
local_bh_disable() / local_irq_disable(). These are the traditional
means of gaining access to per-cpu data, but are fundamentally
non-preemptible.

local_lock_t provides a per-cpu lock, that on !PREEMPT_RT reduces to
no-ops, just like regular spinlocks do on UP.

This gives rise to:

	CPU0			CPU1

	local_lock(B)		spin_lock_irq(A)
	<IRQ>
	  spin_lock(A)		local_lock(B)

Where lockdep then figures things will lock up; which would be true if
B were any other kind of lock. However this is a false positive, no
such deadlock actually exists.

For !RT the above local_lock(B) is preempt_disable(), and there's
obviously no deadlock; alternatively, CPU0's B != CPU1's B.

For RT the argument is that since local_lock() nests inside
spin_lock(), it cannot be used in hardirq context, and therefore CPU0
cannot in fact happen. Even though B is a real lock, it is a
preemptible lock and any threaded-irq would simply schedule out and
let the preempted task (which holds B) continue such that the task on
CPU1 can make progress, after which the threaded-irq resumes and can
finish.

This means that we can never form an IRQ inversion on a local_lock
dependency, so terminate the graph walk when looking for IRQ
inversions when we encounter one.

One consequence is that (for LOCKDEP_SMALL) when we look for redundant
dependencies, A -> B is not redundant in the presence of A -> L -> B.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
[peterz: Changelog]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-01-14 11:20:17 +01:00
Peter Zijlstra 175b1a60e8 locking/lockdep: Clean up check_redundant() a bit
In preparation for adding an TRACE_IRQFLAGS dependent skip function to
check_redundant(), move it below the TRACE_IRQFLAGS #ifdef.

While there, provide a stub function to reduce #ifdef usage.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-01-14 11:20:17 +01:00
Boqun Feng bc2dd71b28 locking/lockdep: Add a skip() function to __bfs()
Some __bfs() walks will have additional iteration constraints (beyond
the path being strong). Provide an additional function to allow
terminating graph walks.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-01-14 11:20:17 +01:00
Peter Zijlstra dfd5e3f5fe locking/lockdep: Mark local_lock_t
The local_lock_t's are special, because they cannot form IRQ
inversions, make sure we can tell them apart from the rest of the
locks.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-01-14 11:20:17 +01:00
Hui Su 65bcf072e2 sched: Use task_current() instead of 'rq->curr == p'
Use the task_current() function where appropriate.

No functional change.

Signed-off-by: Hui Su <sh_def@163.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20201030173223.GA52339@rlk
2021-01-14 11:20:11 +01:00
Vincent Guittot e9b9734b74 sched/fair: Reduce cases for active balance
Active balance is triggered for a number of voluntary cases like misfit
or pinned tasks cases but also after that a number of load balance
attempts failed to migrate a task. There is no need to use active load
balance when the group is overloaded because an overloaded state means
that there is at least one waiting task. Nevertheless, the waiting task
is not selected and detached until the threshold becomes higher than its
load. This threshold increases with the number of failed lb (see the
condition if ((load >> env->sd->nr_balance_failed) > env->imbalance) in
detach_tasks()) and the waiting task will end up to be selected after a
number of attempts.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Link: https://lkml.kernel.org/r/20210107103325.30851-4-vincent.guittot@linaro.org
2021-01-14 11:20:11 +01:00
Vincent Guittot 8a41dfcda7 sched/fair: Don't set LBF_ALL_PINNED unnecessarily
Setting LBF_ALL_PINNED during active load balance is only valid when there
is only 1 running task on the rq otherwise this ends up increasing the
balance interval whereas other tasks could migrate after the next interval
once they become cache-cold as an example.

LBF_ALL_PINNED flag is now always set it by default. It is then cleared
when we find one task that can be pulled when calling detach_tasks() or
during active migration.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Link: https://lkml.kernel.org/r/20210107103325.30851-3-vincent.guittot@linaro.org
2021-01-14 11:20:11 +01:00
Vincent Guittot fc488ffd42 sched/fair: Skip idle cfs_rq
Don't waste time checking whether an idle cfs_rq could be the busiest
queue. Furthermore, this can end up selecting a cfs_rq with a high load
but being idle in case of migrate_load.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Link: https://lkml.kernel.org/r/20210107103325.30851-2-vincent.guittot@linaro.org
2021-01-14 11:20:10 +01:00
Xuewen Yan 8c1f560c1e sched/fair: Avoid stale CPU util_est value for schedutil in task dequeue
CPU (root cfs_rq) estimated utilization (util_est) is currently used in
dequeue_task_fair() to drive frequency selection before it is updated.

with:

CPU_util        : rq->cfs.avg.util_avg
CPU_util_est    : rq->cfs.avg.util_est
CPU_utilization : max(CPU_util, CPU_util_est)
task_util       : p->se.avg.util_avg
task_util_est   : p->se.avg.util_est

dequeue_task_fair():

    /* (1) CPU_util and task_util update + inform schedutil about
           CPU_utilization changes */
    for_each_sched_entity() /* 2 loops */
        (dequeue_entity() ->) update_load_avg() -> cfs_rq_util_change()
         -> cpufreq_update_util() ->...-> sugov_update_[shared\|single]
         -> sugov_get_util() -> cpu_util_cfs()

    /* (2) CPU_util_est and task_util_est update */
    util_est_dequeue()

cpu_util_cfs() uses CPU_utilization which could lead to a false (too
high) utilization value for schedutil in task ramp-down or ramp-up
scenarios during task dequeue.

To mitigate the issue split the util_est update (2) into:

 (A) CPU_util_est update in util_est_dequeue()
 (B) task_util_est update in util_est_update()

Place (A) before (1) and keep (B) where (2) is. The latter is necessary
since (B) relies on task_util update in (1).

Fixes: 7f65ea42eb ("sched/fair: Add util_est on top of PELT")
Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/1608283672-18240-1-git-send-email-xuewen.yan94@gmail.com
2021-01-14 11:20:10 +01:00
Anna-Maria Behnsen e0b257c3b7 sched: Prevent raising SCHED_SOFTIRQ when CPU is !active
SCHED_SOFTIRQ is raised to trigger periodic load balancing. When CPU is not
active, CPU should not participate in load balancing.

The scheduler uses nohz.idle_cpus_mask to keep track of the CPUs which can
do idle load balancing. When bringing a CPU up the CPU is added to the mask
when it reaches the active state, but on teardown the CPU stays in the mask
until it goes offline and invokes sched_cpu_dying().

When SCHED_SOFTIRQ is raised on a !active CPU, there might be a pending
softirq when stopping the tick which triggers a warning in NOHZ code. The
SCHED_SOFTIRQ can also be raised by the scheduler tick which has the same
issue.

Therefore remove the CPU from nohz.idle_cpus_mask when it is marked
inactive and also prevent the scheduler_tick() from raising SCHED_SOFTIRQ
after this point.

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20201215104400.9435-1-anna-maria@linutronix.de
2021-01-14 11:20:09 +01:00
Viresh Kumar a5418be9df sched/core: Rename schedutil_cpu_util() and allow rest of the kernel to use it
There is nothing schedutil specific in schedutil_cpu_util(), rename it
to effective_cpu_util(). Also create and expose another wrapper
sched_cpu_util() which can be used by other parts of the kernel, like
thermal core (that will be done in a later commit).

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/db011961fb3bb8bef1c0eda5cd64564637d3ef31.1607400596.git.viresh.kumar@linaro.org
2021-01-14 11:20:09 +01:00
Viresh Kumar 7d6a905f3d sched/core: Move schedutil_cpu_util() to core.c
There is nothing schedutil specific in schedutil_cpu_util(), move it to
core.c and define it only for CONFIG_SMP.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/c921a362c78e1324f8ebc5aaa12f53e309c5a8a2.1607400596.git.viresh.kumar@linaro.org
2021-01-14 11:20:08 +01:00
Gilad Reti 744ea4e388 bpf: Support PTR_TO_MEM{,_OR_NULL} register spilling
Add support for pointer to mem register spilling, to allow the verifier
to track pointers to valid memory addresses. Such pointers are returned
for example by a successful call of the bpf_ringbuf_reserve helper.

The patch was partially contributed by CyberArk Software, Inc.

Fixes: 457f44363a ("bpf: Implement BPF ring buffer and verifier support for it")
Suggested-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Gilad Reti <gilad.reti@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210113053810.13518-1-gilad.reti@gmail.com
2021-01-13 19:47:43 -08:00
Thomas Gleixner ce09ccc502 genirq: Export irq_check_status_bit()
One of the users can be built modular:

  ERROR: modpost: "irq_check_status_bit" [drivers/perf/arm_spe_pmu.ko] undefined!

Fixes: fdd0296304 ("genirq: Move status flag checks to core")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201227192049.GA195845@roeck-us.net
2021-01-13 15:48:05 +01:00
Andrii Nakryiko 541c3bad8d bpf: Support BPF ksym variables in kernel modules
Add support for directly accessing kernel module variables from BPF programs
using special ldimm64 instructions. This functionality builds upon vmlinux
ksym support, but extends ldimm64 with src_reg=BPF_PSEUDO_BTF_ID to allow
specifying kernel module BTF's FD in insn[1].imm field.

During BPF program load time, verifier will resolve FD to BTF object and will
take reference on BTF object itself and, for module BTFs, corresponding module
as well, to make sure it won't be unloaded from under running BPF program. The
mechanism used is similar to how bpf_prog keeps track of used bpf_maps.

One interesting change is also in how per-CPU variable is determined. The
logic is to find .data..percpu data section in provided BTF, but both vmlinux
and module each have their own .data..percpu entries in BTF. So for module's
case, the search for DATASEC record needs to look at only module's added BTF
types. This is implemented with custom search function.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/bpf/20210112075520.4103414-6-andrii@kernel.org
2021-01-12 17:24:30 -08:00
Brendan Jackman 28a8add641 bpf: Fix a verifier message for alloc size helper arg
The error message here is misleading, the argument will be rejected unless
it is a known constant.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210112123913.2016804-1-jackmanb@google.com
2021-01-12 21:41:17 +01:00
Thomas Gleixner 4bae052dde irqchip fixes for 5.11, take #1
- Fix the MIPS CPU interrupt controller hierarchy
 - Simplify the PRUSS Kconfig entry
 - Eliminate trivial build warnings on the MIPS Loongson liointc
 - Fix error path in devm_platform_get_irqs_affinity()
 - Turn the BCM2836 IPI irq_eoi callback into irq_ack
 - Fix initialisation of on-stack msi_alloc_info
 - Cleanup spurious comma in irq-sl28cpld
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Merge tag 'irqchip-fixes-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent

Pull irqchip fixes from Marc Zyngier:

 - Fix the MIPS CPU interrupt controller hierarchy
 - Simplify the PRUSS Kconfig entry
 - Eliminate trivial build warnings on the MIPS Loongson liointc
 - Fix error path in devm_platform_get_irqs_affinity()
 - Turn the BCM2836 IPI irq_eoi callback into irq_ack
 - Fix initialisation of on-stack msi_alloc_info
 - Cleanup spurious comma in irq-sl28cpld

Link: https://lore.kernel.org/r/20210110110001.2328708-1-maz@kernel.org
2021-01-12 21:23:55 +01:00
Geert Uytterhoeven e3fab2f3de ntp: Fix RTC synchronization on 32-bit platforms
Due to an integer overflow, RTC synchronization now happens every 2s
instead of the intended 11 minutes.  Fix this by forcing 64-bit
arithmetic for the sync period calculation.

Annotate the other place which multiplies seconds for consistency as well.

Fixes: c9e6189fb0 ("ntp: Make the RTC synchronization more reliable")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210111103956.290378-1-geert+renesas@glider.be
2021-01-12 21:13:01 +01:00
Chunguang Xu aba428a0c6 timekeeping: Remove unused get_seconds()
The get_seconds() cleanup seems to have been completed, now it is
time to delete the legacy interface to avoid misuse later.

Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/1606816351-26900-1-git-send-email-brookxu@tencent.com
2021-01-12 21:13:01 +01:00
Andrii Nakryiko bcc5e6162d bpf: Allow empty module BTFs
Some modules don't declare any new types and end up with an empty BTF,
containing only valid BTF header and no types or strings sections. This
currently causes BTF validation error. There is nothing wrong with such BTF,
so fix the issue by allowing module BTFs with no types or strings.

Fixes: 36e68442d1 ("bpf: Load and verify kernel module BTFs")
Reported-by: Christopher William Snowhill <chris@kode54.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210110070341.1380086-1-andrii@kernel.org
2021-01-12 21:11:30 +01:00
Peter Zijlstra 77ca93a6b1 locking/lockdep: Avoid noinstr warning for DEBUG_LOCKDEP
vmlinux.o: warning: objtool: lock_is_held_type()+0x60: call to check_flags.part.0() leaves .noinstr.text section

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210106144017.652218215@infradead.org
2021-01-12 21:10:59 +01:00
Peter Zijlstra 0afda3a888 locking/lockdep: Cure noinstr fail
When the compiler doesn't feel like inlining, it causes a noinstr
fail:

  vmlinux.o: warning: objtool: lock_is_held_type()+0xb: call to lockdep_enabled() leaves .noinstr.text section

Fixes: 4d004099a6 ("lockdep: Fix lockdep recursion")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210106144017.592595176@infradead.org
2021-01-12 21:10:59 +01:00
Stanislav Fomichev 4be34f3d07 bpf: Don't leak memory in bpf getsockopt when optlen == 0
optlen == 0 indicates that the kernel should ignore BPF buffer
and use the original one from the user. We, however, forget
to free the temporary buffer that we've allocated for BPF.

Fixes: d8fe449a9c ("bpf: Don't return EINVAL from {get,set}sockopt when optlen > PAGE_SIZE")
Reported-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210112162829.775079-1-sdf@google.com
2021-01-12 21:05:07 +01:00
KP Singh 84d571d46c bpf: Fix typo in bpf_inode_storage.c
Fix "gurranteed" -> "guaranteed" in bpf_inode_storage.c

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210112075525.256820-4-kpsingh@kernel.org
2021-01-12 16:07:57 +01:00
KP Singh 1a9c72ad4c bpf: Local storage helpers should check nullness of owner ptr passed
The verifier allows ARG_PTR_TO_BTF_ID helper arguments to be NULL, so
helper implementations need to check this before dereferencing them.
This was already fixed for the socket storage helpers but not for task
and inode.

The issue can be reproduced by attaching an LSM program to
inode_rename hook (called when moving files) which tries to get the
inode of the new file without checking for its nullness and then trying
to move an existing file to a new path:

  mv existing_file new_file_does_not_exist

The report including the sample program and the steps for reproducing
the bug:

  https://lore.kernel.org/bpf/CANaYP3HWkH91SN=wTNO9FL_2ztHfqcXKX38SSE-JJ2voh+vssw@mail.gmail.com

Fixes: 4cf1bc1f10 ("bpf: Implement task local storage")
Fixes: 8ea636848a ("bpf: Implement bpf_local_storage for inodes")
Reported-by: Gilad Reti <gilad.reti@gmail.com>
Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210112075525.256820-3-kpsingh@kernel.org
2021-01-12 16:07:56 +01:00
Daniel Vetter 71a1d8ed90 resource: Move devmem revoke code to resource framework
We want all iomem mmaps to consistently revoke ptes when the kernel
takes over and CONFIG_IO_STRICT_DEVMEM is enabled. This includes the
pci bar mmaps available through procfs and sysfs, which currently do
not revoke mappings.

To prepare for this, move the code from the /dev/kmem driver to
kernel/resource.c.

During review Jason spotted that barriers are used somewhat
inconsistently. Fix that up while we shuffle this code, since it
doesn't have an actual impact at runtime. Otherwise no semantic and
behavioural changes intended, just code extraction and adjusting
comments and names.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Kees Cook <keescook@chromium.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-11-daniel.vetter@ffwll.ch
2021-01-12 14:26:31 +01:00
Jiri Olsa 5541075a34 bpf: Prevent double bpf_prog_put call from bpf_tracing_prog_attach
The bpf_tracing_prog_attach error path calls bpf_prog_put
on prog, which causes refcount underflow when it's called
from link_create function.

  link_create
    prog = bpf_prog_get              <-- get
    ...
    tracing_bpf_link_attach(prog..
      bpf_tracing_prog_attach(prog..
        out_put_prog:
          bpf_prog_put(prog);        <-- put

    if (ret < 0)
      bpf_prog_put(prog);            <-- put

Removing bpf_prog_put call from bpf_tracing_prog_attach
and making sure its callers call it instead.

Fixes: 4a1e7c0c63 ("bpf: Support attaching freplace programs to multiple attach points")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210111191650.1241578-1-jolsa@kernel.org
2021-01-12 00:17:34 +01:00
Linus Torvalds a0d54b4f5b Blacklist properly on all archs
The way to blacklist notrace functions for kprobes was not using
 the proper kconfig which caused some archs (powerpc) from blacklisting
 them.
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Merge tag 'trace-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Blacklist properly on all archs.

  The code to blacklist notrace functions for kprobes was not using the
  right kconfig option, which caused some archs (powerpc) to possibly
  not blacklist them"

* tag 'trace-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/kprobes: Do the notrace functions check without kprobes on ftrace
2021-01-11 14:37:13 -08:00
Masami Hiramatsu 7bb83f6fc4 tracing/kprobes: Do the notrace functions check without kprobes on ftrace
Enable the notrace function check on the architecture which doesn't
support kprobes on ftrace but support dynamic ftrace. This notrace
function check is not only for the kprobes on ftrace but also
sw-breakpoint based kprobes.
Thus there is no reason to limit this check for the arch which
supports kprobes on ftrace.

This also changes the dependency of Kconfig. Because kprobe event
uses the function tracer's address list for identifying notrace
function, if the CONFIG_DYNAMIC_FTRACE=n, it can not check whether
the target function is notrace or not.

Link: https://lkml.kernel.org/r/20210105065730.2634785-1-naveen.n.rao@linux.vnet.ibm.com
Link: https://lkml.kernel.org/r/161007957862.114704.4512260007555399463.stgit@devnote2

Cc: stable@vger.kernel.org
Fixes: 45408c4f92 ("tracing: kprobes: Prohibit probing on notrace function")
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-11 16:09:53 -05:00
Paul Cercueil 04b38d0125 seccomp: Add missing return in non-void function
We don't actually care about the value, since the kernel will panic
before that; but a value should nonetheless be returned, otherwise the
compiler will complain.

Fixes: 8112c4f140 ("seccomp: remove 2-phase API")
Cc: stable@vger.kernel.org # 4.7+
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210111172839.640914-1-paul@crapouillou.net
2021-01-11 12:05:14 -08:00
Yanfei Xu cb5021ca62
kthread: remove comments about old _do_fork() helper
The old _do_fork() helper has been removed in favor of kernel_clone().
Here correct some comments which still contain _do_fork()

Link: https://lore.kernel.org/r/20210111104807.18022-1-yanfei.xu@windriver.com
Cc: christian@brauner.io
Cc: linux-kernel@vger.kernel.org
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-11 15:11:56 +01:00
Alexander Guril 96e1e9846c
Kernel: fork.c: Fix coding style: Do not use {} around single-line statements
Fixed two coding style issues in kernel/fork.c
Do not use {} around single-line statements.

Cc: linux-kernel@vger.kernel.org
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Alexander Guril <alexander.guril02@gmail.com>
Link: https://lore.kernel.org/r/20201226114021.2589-1-alexander.guril02@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-11 12:55:01 +01:00
Jann Horn adc5d87572
signal: Add missing __user annotation to copy_siginfo_from_user_any
copy_siginfo_from_user_any() takes a userspace pointer as second
argument; annotate the parameter type accordingly.

Signed-off-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/r/20201207000252.138564-1-jannh@google.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-11 12:55:00 +01:00
Linus Torvalds 4ad9a28f56 Staging driver fixes for 5.11-rc3
Here are some small staging driver fixes for 5.11-rc3.  Nothing major,
 just resolving some reported issues:
 	- cleanup some remaining mentions of the ION drivers that were
 	  removed in 5.11-rc1
 	- comedi driver bugfix
 	- 2 error path memory leak fixes
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-5.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging driver fixes from Greg KH:
 "Here are some small staging driver fixes for 5.11-rc3. Nothing major,
  just resolving some reported issues:

   - cleanup some remaining mentions of the ION drivers that were
     removed in 5.11-rc1

   - comedi driver bugfix

   - two error path memory leak fixes

  All have been in linux-next for a while with no reported issues"

* tag 'staging-5.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: ION: remove some references to CONFIG_ION
  staging: mt7621-dma: Fix a resource leak in an error handling path
  Staging: comedi: Return -EFAULT if copy_to_user() fails
  staging: spmi: hisi-spmi-controller: Fix some error handling paths
2021-01-10 12:28:07 -08:00
Sami Tolvanen 3b15cdc159 tracing: move function tracer options to Kconfig
Move function tracer options to Kconfig to make it easier to add
new methods for generating __mcount_loc, and to make the options
available also when building kernel modules.

Note that FTRACE_MCOUNT_USE_* options are updated on rebuild and
therefore, work even if the .config was generated in a different
environment.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20201211184633.3213045-2-samitolvanen@google.com
2021-01-08 15:59:02 -08:00
Leah Neukirchen 619775c3cf bpf: Remove unnecessary <argp.h> include from preload/iterators
This program does not use argp (which is a glibcism). Instead include <errno.h>
directly, which was pulled in by <argp.h>.

Signed-off-by: Leah Neukirchen <leah@vuxu.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201216100306.30942-1-leah@vuxu.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-01-08 13:39:24 -08:00
Jens Axboe 35d0b389f3 task_work: unconditionally run task_work from get_signal()
Song reported a boot regression in a kvm image with 5.11-rc, and bisected
it down to the below patch. Debugging this issue, turns out that the boot
stalled when a task is waiting on a pipe being released. As we no longer
run task_work from get_signal() unless it's queued with TWA_SIGNAL, the
task goes idle without running the task_work. This prevents ->release()
from being called on the pipe, which another boot task is waiting on.

For now, re-instate the unconditional task_work run from get_signal().
For 5.12, we'll collapse TWA_RESUME and TWA_SIGNAL, as it no longer
makes sense to have a distinction between the two. This will turn
task_work notification into a simple boolean, whether to notify or not.

Fixes: 98b89b649f ("signal: kill JOBCTL_TASK_WORK")
Reported-by: Song Liu <songliubraving@fb.com>
Tested-by: John Stultz <john.stultz@linaro.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang version 11.0.1
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-08 09:14:21 -07:00