Commit Graph

25 Commits

Author SHA1 Message Date
AKASHI Takahiro a1ae65b219 arm64: add seccomp support
secure_computing() is called first in syscall_trace_enter() so that
a system call will be aborted quickly without doing succeeding syscall
tracing if seccomp rules want to deny that system call.

On compat task, syscall numbers for system calls allowed in seccomp mode 1
are different from those on normal tasks, and so _NR_seccomp_xxx_32's need
to be redefined.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-28 10:24:59 +00:00
AKASHI Takahiro 766a85d7bc arm64: ptrace: add NT_ARM_SYSTEM_CALL regset
This regeset is intended to be used to get and set a system call number
while tracing.
There was some discussion about possible approaches to do so:

(1) modify x8 register with ptrace(PTRACE_SETREGSET) indirectly,
    and update regs->syscallno later on in syscall_trace_enter(), or
(2) define a dedicated regset for this purpose as on s390, or
(3) support ptrace(PTRACE_SET_SYSCALL) as on arch/arm

Thinking of the fact that user_pt_regs doesn't expose 'syscallno' to
tracer as well as that secure_computing() expects a changed syscall number,
especially case of -1, to be visible before this function returns in
syscall_trace_enter(), (1) doesn't work well.
We will take (2) since it looks much cleaner.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-28 10:19:49 +00:00
Linus Torvalds ab074ade9c Merge git://git.infradead.org/users/eparis/audit
Pull audit updates from Eric Paris:
 "So this change across a whole bunch of arches really solves one basic
  problem.  We want to audit when seccomp is killing a process.  seccomp
  hooks in before the audit syscall entry code.  audit_syscall_entry
  took as an argument the arch of the given syscall.  Since the arch is
  part of what makes a syscall number meaningful it's an important part
  of the record, but it isn't available when seccomp shoots the
  syscall...

  For most arch's we have a better way to get the arch (syscall_get_arch)
  So the solution was two fold: Implement syscall_get_arch() everywhere
  there is audit which didn't have it.  Use syscall_get_arch() in the
  seccomp audit code.  Having syscall_get_arch() everywhere meant it was
  a useless flag on the stack and we could get rid of it for the typical
  syscall entry.

  The other changes inside the audit system aren't grand, fixed some
  records that had invalid spaces.  Better locking around the task comm
  field.  Removing some dead functions and structs.  Make some things
  static.  Really minor stuff"

* git://git.infradead.org/users/eparis/audit: (31 commits)
  audit: rename audit_log_remove_rule to disambiguate for trees
  audit: cull redundancy in audit_rule_change
  audit: WARN if audit_rule_change called illegally
  audit: put rule existence check in canonical order
  next: openrisc: Fix build
  audit: get comm using lock to avoid race in string printing
  audit: remove open_arg() function that is never used
  audit: correct AUDIT_GET_FEATURE return message type
  audit: set nlmsg_len for multicast messages.
  audit: use union for audit_field values since they are mutually exclusive
  audit: invalid op= values for rules
  audit: use atomic_t to simplify audit_serial()
  kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0]
  audit: reduce scope of audit_log_fcaps
  audit: reduce scope of audit_net_id
  audit: arm64: Remove the audit arch argument to audit_syscall_entry
  arm64: audit: Add audit hook in syscall_trace_enter/exit()
  audit: x86: drop arch from __audit_syscall_entry() interface
  sparc: implement is_32bit_task
  sparc: properly conditionalize use of TIF_32BIT
  ...
2014-10-19 16:25:56 -07:00
Eric Paris 4913c59890 audit: arm64: Remove the audit arch argument to audit_syscall_entry
The arm64 tree added calls to audit_syscall_entry() and rightly included
the syscall number.  The interface has since been changed to not need
the syscall number.  As such, arm64 should no longer pass that value.

Signed-off-by: Eric Paris <eparis@redhat.com>
2014-09-23 16:25:34 -04:00
AKASHI Takahiro 23fed6218d arm64: audit: Add audit hook in syscall_trace_enter/exit()
This patch adds auditing functions on entry to or exit from
every system call invocation.

Acked-by: Richard Guy Briggs <rgb@redhat.com>
Acked-by Will Deacon <will.deacon@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-09-23 16:24:04 -04:00
Will Deacon 85487edd25 arm64: ptrace: fix compat reg getter/setter return values
copy_{to,from}_user return the number of bytes remaining on failure, not
an error code.

This patch returns -EFAULT when the copy operation didn't complete,
rather than expose the number of bytes not copied directly to userspace.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-08-28 20:01:42 +01:00
Will Deacon 27d7ff273c arm64: ptrace: fix compat hardware watchpoint reporting
I'm not sure what I was on when I wrote this, but when iterating over
the hardware watchpoint array (hbp_watch_array), our index is off by
ARM_MAX_BRP, so we walk off the end of our thread_struct...

... except, a dodgy condition in the loop means that it never executes
at all (bp cannot be NULL).

This patch fixes the code so that we remove the bp check and use the
correct index for accessing the watchpoint structures.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-08-28 20:01:36 +01:00
Will Deacon 44b375070f Revert "arm64: Do not invoke audit_syscall_* functions if !CONFIG_AUDIT_SYSCALL"
For some reason, the audit patches didn't make it out of -next this
merge window, so revert our temporary hack and let the audit guys deal
with fixing up -next.

This reverts commit 2a8f45b040.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-08-19 22:05:45 +01:00
Catalin Marinas 2a8f45b040 arm64: Do not invoke audit_syscall_* functions if !CONFIG_AUDIT_SYSCALL
This is a temporary patch to be able to compile the kernel in linux-next
where the audit_syscall_* API has been changed. To be reverted once the
proper arm64 fix can be applied.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-24 16:01:17 +01:00
AKASHI Takahiro 5701ede884 arm64: audit: Add audit hook in syscall_trace_enter/exit()
This patch adds auditing functions on entry to or exit from
every system call invocation.

Acked-by: Richard Guy Briggs <rgb@redhat.com>
Acked-by Will Deacon <will.deacon@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-10 11:06:00 +01:00
Victor Kamensky 2227901a02 arm64: ptrace: fix empty registers set in prstatus of aarch32 process core
Currently core file of aarch32 process prstatus note has empty
registers set. As result aarch32 core files create by V8 kernel are
not very useful.

It happens because compat_gpr_get and compat_gpr_set functions can
copy registers values to/from either kbuf or ubuf. ELF core file
collection function fill_thread_core_info calls compat_gpr_get
with kbuf set and ubuf set to 0. But current compat_gpr_get and
compat_gpr_set function handle copy to/from only ubuf case.

Fix is to handle kbuf and ubuf as two separate cases in similar
way as other functions like user_regset_copyout, user_regset_copyin do.

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-06-18 12:41:14 +01:00
Will Deacon c168870704 arm64: ptrace: change fs when passing kernel pointer to regset code
Our compat PTRACE_POKEUSR implementation simply passes the user data to
regset_copy_from_user after some simple range checking. Unfortunately,
the data in question has already been copied to the kernel stack by this
point, so the subsequent access_ok check fails and the ptrace request
returns -EFAULT. This causes problems tracing fork() with older versions
of strace.

This patch briefly changes the fs to KERNEL_DS, so that the access_ok
check passes even with a kernel address.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-06-18 12:40:57 +01:00
AKASHI Takahiro 055b1212d1 arm64: ftrace: Add system call tracepoint
This patch allows system call entry or exit to be traced as ftrace events,
ie. sys_enter_*/sys_exit_*, if CONFIG_FTRACE_SYSCALLS is enabled.
Those events appear and can be controlled under
    ${sysfs}/tracing/events/syscalls/

Please note that we can't trace compat system calls here because
AArch32 mode does not share the same syscall table with AArch64.
Just define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS in order to avoid unexpected
results (bogus syscalls reported or even hang-up).

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-05-29 09:08:33 +01:00
Catalin Marinas cf5c95db57 2014-05-15 for-3.16 pull request
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.14 (GNU/Linux)
 
 iQF8BAABCgBmBQJTdT+DXxSAAAAAAC4AKGlzc3Vlci1mcHJAbm90YXRpb25zLm9w
 ZW5wZ3AuZmlmdGhob3JzZW1hbi5uZXQ5Q0QyQTBEQTZBRDhGNzMzMDE3NUUyQkJD
 MjM3MjA3RTk1NzRGQTdEAAoJEMI3IH6VdPp9jL8H/3kzXh+5rZycb5r48E6Cic/a
 Gl0NmRjGtbsxLZcvd8NR3cDol1c9mEAelFrwSA3ar0W91hDf9gsEgxYSBcGKfX/b
 sxqzhFoArMDitvu8QQ38SMIlXaGokW3sevj4B93ljw9DqhFR/BvJctmVfyNuPLpp
 fFZh0JRyHnkMkXKMJKtYyiXRgfGiJ90rGHPRZLJW7zCIk0/oYd4LESpnqWC+cGKg
 w8WIe0Vu4CsiQffkWRmMMJmcJIVayJXAtMHOyBNCKMnYziZSqs+JIUwhbPCxci51
 vTxWOFs/CAeZp8mrlHR2TD3dHtzP8c/NSL7E3k4QA0tYReA8T3XHwhRmqtHCp7E=
 =sllM
 -----END PGP SIGNATURE-----

Merge tag 'for-3.16' of git://git.linaro.org/people/ard.biesheuvel/linux-arm into upstream

FPSIMD register bank context switching and crypto algorithms
optimisations for arm64 from Ard Biesheuvel.

* tag 'for-3.16' of git://git.linaro.org/people/ard.biesheuvel/linux-arm:
  arm64/crypto: AES-ECB/CBC/CTR/XTS using ARMv8 NEON and Crypto Extensions
  arm64: pull in <asm/simd.h> from asm-generic
  arm64/crypto: AES in CCM mode using ARMv8 Crypto Extensions
  arm64/crypto: AES using ARMv8 Crypto Extensions
  arm64/crypto: GHASH secure hash using ARMv8 Crypto Extensions
  arm64/crypto: SHA-224/SHA-256 using ARMv8 Crypto Extensions
  arm64/crypto: SHA-1 using ARMv8 Crypto Extensions
  arm64: add support for kernel mode NEON in interrupt context
  arm64: defer reloading a task's FPSIMD state to userland resume
  arm64: add abstractions for FPSIMD state manipulation
  asm-generic: allow generic unaligned access if the arch supports it

Conflicts:
	arch/arm64/include/asm/thread_info.h
2014-05-16 10:05:11 +01:00
AKASHI Takahiro fd92d4a54a arm64: is_compat_task is defined both in asm/compat.h and linux/compat.h
Some kernel files may include both linux/compat.h and asm/compat.h directly
or indirectly. Since both header files contain is_compat_task() under
!CONFIG_COMPAT, compiling them with !CONFIG_COMPAT will eventually fail.
Such files include kernel/auditsc.c, kernel/seccomp.c and init/do_mountfs.c
(do_mountfs.c may read asm/compat.h via asm/ftrace.h once ftrace is
implemented).

So this patch proactively
1) removes is_compat_task() under !CONFIG_COMPAT from asm/compat.h
2) replaces asm/compat.h to linux/compat.h in kernel/*.c,
   but asm/compat.h is still necessary in ptrace.c and process.c because
   they use is_compat_thread().

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-12 16:43:29 +01:00
AKASHI Takahiro 3157858fef arm64: split syscall_trace() into separate functions for enter/exit
As done in arm, this change makes it easy to confirm we invoke syscall
related hooks, including syscall tracepoint, audit and seccomp which would
be implemented later, in correct order. That is, undoing operations in the
opposite order on exit that they were done on entry.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-12 16:43:29 +01:00
Ard Biesheuvel 005f78cd88 arm64: defer reloading a task's FPSIMD state to userland resume
If a task gets scheduled out and back in again and nothing has touched
its FPSIMD state in the mean time, there is really no reason to reload
it from memory. Similarly, repeated calls to kernel_neon_begin() and
kernel_neon_end() will preserve and restore the FPSIMD state every time.

This patch defers the FPSIMD state restore to the last possible moment,
i.e., right before the task returns to userland. If a task does not return to
userland at all (for any reason), the existing FPSIMD state is preserved
and may be reused by the owning task if it gets scheduled in again on the
same CPU.

This patch adds two more functions to abstract away from straight FPSIMD
register file saves and restores:
- fpsimd_restore_current_state -> ensure current's FPSIMD state is loaded
- fpsimd_flush_task_state -> invalidate live copies of a task's FPSIMD state

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2014-05-08 11:31:57 +02:00
Will Deacon cdc27c2784 arm64: ptrace: avoid using HW_BREAKPOINT_EMPTY for disabled events
Commit 8f34a1da35 ("arm64: ptrace: use HW_BREAKPOINT_EMPTY type for
disabled breakpoints") fixed an issue with GDB trying to zero breakpoint
control registers. The problem there is that the arch hw_breakpoint code
will attempt to create a (disabled), execute breakpoint of length 0.

This will fail validation and report unexpected failure to GDB. To avoid
this, we treated disabled breakpoints as HW_BREAKPOINT_EMPTY, but that
seems to have broken with recent kernels, causing watchpoints to be
treated as TYPE_INST in the core code and returning ENOSPC for any
further breakpoints.

This patch fixes the problem by prioritising the `enable' field of the
breakpoint: if it is cleared, we simply update the perf_event_attr to
indicate that the thing is disabled and don't bother changing either the
type or the length. This reinforces the behaviour that the breakpoint
control register is essentially read-only apart from the enable bit
when disabling a breakpoint.

Cc: <stable@vger.kernel.org>
Reported-by: Aaron Liu <liucy214@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-12-19 17:41:25 +00:00
Matthew Leach 6a2e5e521c arm64: ptrace: fix compat registes get/set to be endian clean
On a BE system the wrong half of the X registers is retrieved/written
when attempting to get/set the value of aarch32 registers through
ptrace.

Ensure that types are the correct width so that the relevant
casting occurs.

Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-11-28 18:01:28 +00:00
Will Deacon 1442b6ed24 arm64: debug: consolidate software breakpoint handlers
The software breakpoint handlers are hooked in directly from ptrace,
which makes it difficult to add additional handlers for things like
kprobes and kgdb.

This patch moves the handling code into debug-monitors.c, where we can
dispatch to different debug subsystems more easily.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-06-12 11:23:02 +01:00
Will Deacon 8f34a1da35 arm64: ptrace: use HW_BREAKPOINT_EMPTY type for disabled breakpoints
If a debugger tries to zero a hardware debug control register, the
kernel will try to infer both the type and length of the breakpoint
in order to sanity-check against the requested regset type. This will
fail because the encoding will appear as a zero-length breakpoint.

This patch changes the control register setting so that disabled
breakpoints are treated as HW_BREAKPOINT_EMPTY and no further
sanity-checking is required.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-10-18 20:15:34 +01:00
Will Deacon 7797d17c59 arm64: ptrace: make structure padding explicit for debug registers
The user_hwdebug_state structure contains implicit padding to conform to
the alignment requirements of the AArch64 ABI (namely that aggregates
must be aligned to their most aligned member).

This patch fixes the ptrace functions operating on struct
user_hwdebug_state so that the padding is handled correctly.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-10-18 20:15:31 +01:00
Catalin Marinas 7606c37d4a arm64: Do not export the compat-specific definitions to the user
This patch adds #ifdef __KERNEL__ guards around the COMPAT_* definitions
to avoid exporting them to user. AArch32 user requiring the kernel
headers must use those generated with ARCH=arm.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
2012-10-11 10:39:08 +01:00
Will Deacon 27aa55c5e5 arm64: ptrace: remove obsolete ptrace request numbers from user headers
The use of regsets has removed the need for many private ptrace requests,
so remove the corresponding definitions from the user-visible ptrace.h

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-09-27 11:46:22 +01:00
Will Deacon 478fcb2cdb arm64: Debugging support
This patch adds ptrace, debug monitors and hardware breakpoints support.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-09-17 13:42:14 +01:00