Commit Graph

148 Commits

Author SHA1 Message Date
Michael Ellerman ca6d5149d2 powerpc/ptrace: Simplify vr_get/set() to avoid GCC warning
GCC 8 warns about the logic in vr_get/set(), which with -Werror breaks
the build:

  In function ‘user_regset_copyin’,
      inlined from ‘vr_set’ at arch/powerpc/kernel/ptrace.c:628:9:
  include/linux/regset.h:295:4: error: ‘memcpy’ offset [-527, -529] is
  out of the bounds [0, 16] of object ‘vrsave’ with type ‘union
  <anonymous>’ [-Werror=array-bounds]
  arch/powerpc/kernel/ptrace.c: In function ‘vr_set’:
  arch/powerpc/kernel/ptrace.c:623:5: note: ‘vrsave’ declared here
     } vrsave;

This has been identified as a regression in GCC, see GCC bug 88273.

However we can avoid the warning and also simplify the logic and make
it more robust.

Currently we pass -1 as end_pos to user_regset_copyout(). This says
"copy up to the end of the regset".

The definition of the regset is:
	[REGSET_VMX] = {
		.core_note_type = NT_PPC_VMX, .n = 34,
		.size = sizeof(vector128), .align = sizeof(vector128),
		.active = vr_active, .get = vr_get, .set = vr_set
	},

The end is calculated as (n * size), ie. 34 * sizeof(vector128).

In vr_get/set() we pass start_pos as 33 * sizeof(vector128), meaning
we can copy up to sizeof(vector128) into/out-of vrsave.

The on-stack vrsave is defined as:
  union {
	  elf_vrreg_t reg;
	  u32 word;
  } vrsave;

And elf_vrreg_t is:
  typedef __vector128 elf_vrreg_t;

So there is no bug, but we rely on all those sizes lining up,
otherwise we would have a kernel stack exposure/overwrite on our
hands.

Rather than relying on that we can pass an explict end_pos based on
the sizeof(vrsave). The result should be exactly the same but it's
more obviously not over-reading/writing the stack and it avoids the
compiler warning.

Reported-by: Meelis Roos <mroos@linux.ee>
Reported-by: Mathieu Malaterre <malat@debian.org>
Cc: stable@vger.kernel.org
Tested-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:14 +11:00
Breno Leitao ebb0e13ead powerpc/ptrace: Mitigate potential Spectre v1
'regno' is directly controlled by user space, hence leading to a potential
exploitation of the Spectre variant 1 vulnerability.

On PTRACE_SETREGS and PTRACE_GETREGS requests, user space passes the
register number that would be read or written. This register number is
called 'regno' which is part of the 'addr' syscall parameter.

This 'regno' value is checked against the maximum pt_regs structure size,
and then used to dereference it, which matches the initial part of a
Spectre v1 (and Spectre v1.1) attack. The dereferenced value, then,
is returned to userspace in the GETREGS case.

This patch sanitizes 'regno' before using it to dereference pt_reg.

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2

Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-07 00:29:20 +11:00
Dmitry V. Levin 8dbdec0bcb powerpc/ptrace: Combine SYSCALL_EMU & SYSCALL_TRACE handling
Combine the SYSCALL_EMU and SYSCALL_TRACE handling so that we only
call tracehook_report_syscall_entry() in one place.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
[mpe: Flesh out change log, s/cached_flags/flags/, reflow comments]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Elvira Khabirova a225f15674 powerpc/ptrace: replace ptrace_report_syscall() with a tracehook call
Arch code should use tracehook_*() helpers, as documented in
include/linux/tracehook.h, ptrace_report_syscall() is not expected to
be used outside that file.

The patch does not look very nice, but at least it is correct
and opens the way for PTRACE_GET_SYSCALL_INFO API.

Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>
Fixes: 5521eb4bca ("powerpc/ptrace: Add support for PTRACE_SYSEMU")
Signed-off-by: Elvira Khabirova <lineprinter@altlinux.org>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
[mpe: Take this as a minimal fix for 4.20, we'll rework it later]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-10 15:19:58 +11:00
Nicholas Piggin 4c2de74cc8 powerpc/64: Interrupts save PPR on stack rather than thread_struct
PPR is the odd register out when it comes to interrupt handling, it is
saved in current->thread.ppr while all others are saved on the stack.

The difficulty with this is that accessing thread.ppr can cause a SLB
fault, but the SLB fault handler implementation in C change had
assumed the normal exception entry handlers would not cause an SLB
fault.

Fix this by allocating room in the interrupt stack to save PPR.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Michael Ellerman 3eeacd9f4e powerpc/ptrace: Don't use sizeof(struct pt_regs) in ptrace code
Now that we've split the user & kernel versions of pt_regs we need to
be more careful in the ptrace code.

For now we've ensured the location of the fields in both structs is
the same, so most of the ptrace code doesn't need updating.

But there are a few places where we use sizeof(pt_regs), and these
will be wrong as soon as we increase the size of the kernel structure.

So flip them all to use sizeof(user_pt_regs).

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Michael Ellerman 002af9391b powerpc: Split user/kernel definitions of struct pt_regs
We use a shared definition for struct pt_regs in uapi/asm/ptrace.h.
That means the layout of the structure is ABI, ie. we can't change it.

That would be fine if it was only used to describe the user-visible
register state of a process, but it's also the struct we use in the
kernel to describe the registers saved in an interrupt frame.

We'd like more flexibility in the content (and possibly layout) of the
kernel version of the struct, but currently that's not possible.

So split the definition into a user-visible definition which remains
unchanged, and a kernel internal one.

At the moment they're still identical, and we check that at build
time. That's because we have code (in ptrace etc.) that assumes that
they are the same. We will fix that code in future patches, and then
we can break the strict symmetry between the two structs.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Breno Leitao 5521eb4bca powerpc/ptrace: Add support for PTRACE_SYSEMU
This is a patch that adds support for PTRACE_SYSEMU ptrace request in
PowerPC architecture.

When ptrace(PTRACE_SYSEMU, ...) request is called, it will be handled by
the arch independent function ptrace_resume(), which will tag the task with
the TIF_SYSCALL_EMU flag. This flag needs to be handled from a platform
dependent point of view, which is what this patch does.

This patch adds this task's flag as part of the _TIF_SYSCALL_DOTRACE, which
is the MACRO that is used to trace syscalls at entrance/exit.

Since TIF_SYSCALL_EMU is now part of _TIF_SYSCALL_DOTRACE, if the task has
_TIF_SYSCALL_DOTRACE set, it will hit do_syscall_trace_enter() at syscall
entrance and do_syscall_trace_leave() at syscall leave.
do_syscall_trace_enter() needs to handle the TIF_SYSCALL_EMU flag properly,
which will interrupt the syscall executing if TIF_SYSCALL_EMU is set. The
output values should not be changed, i.e. the return value (r3) should
contain the original syscall argument on exit.

With this flag set, the syscall is not executed fundamentally, because
do_syscall_trace_enter() is returning -1 which is bigger than NR_syscall,
thus, skipping the syscall execution and exiting userspace.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-03 15:40:04 +10:00
Al Viro 6bcdd2972b powerpc/ptrace: Use copy_{from, to}_user() rather than open-coding
In PPC_PTRACE_GETHWDBGINFO and PPC_PTRACE_SETHWDEBUG we do an
access_ok() check and then __copy_{from,to}_user().

Instead we should just use copy_{from,to}_user() which does all that
for us and is less error prone.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:43:41 +10:00
Michael Neuling 4f7c06e26e powerpc/ptrace: Fix setting 512B aligned breakpoints with PTRACE_SET_DEBUGREG
In commit e2a800beac ("powerpc/hw_brk: Fix off by one error when
validating DAWR region end") we fixed setting the DAWR end point to
its max value via PPC_PTRACE_SETHWDEBUG. Unfortunately we broke
PTRACE_SET_DEBUGREG when setting a 512 byte aligned breakpoint.

PTRACE_SET_DEBUGREG currently sets the length of the breakpoint to
zero (memset() in hw_breakpoint_init()). This worked with
arch_validate_hwbkpt_settings() before the above patch was applied but
is now broken if the breakpoint is 512byte aligned.

This sets the length of the breakpoint to 8 bytes when using
PTRACE_SET_DEBUGREG.

Fixes: e2a800beac ("powerpc/hw_brk: Fix off by one error when validating DAWR region end")
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-21 14:48:01 +10:00
Michael Neuling 85ce9a5d57 powerpc: Update ptrace to use ppc_breakpoint_available()
This updates the ptrace code to use ppc_breakpoint_available().

We now advertise via PPC_PTRACE_GETHWDBGINFO zero breakpoints when the
DAWR is missing (ie. POWER9). This results in GDB falling back to
software emulation of the breakpoint (which is slow).

For the features advertised by PPC_PTRACE_GETHWDBGINFO, we keep
advertising DAWR as if we don't GDB assumes 1 breakpoint irrespective
of the number of breakpoints advertised. GDB then fails later when
trying to set this one breakpoint.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27 23:52:44 +11:00
Thiago Jung Bauermann c5cc1f4df6 powerpc/ptrace: Add memory protection key regset
The AMR/IAMR/UAMOR are part of the program context.
Allow it to be accessed via ptrace and through core files.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:06 +11:00
Madhavan Srinivasan 4e26bc4a4e powerpc/64: Rename soft_enabled to irq_soft_mask
Rename the paca->soft_enabled to paca->irq_soft_mask as it is no
longer used as a flag for interrupt state, but a mask.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:01 +11:00
Madhavan Srinivasan a8a4b03ab9 powerpc: Hard wire PT_SOFTE value to 1 in ptrace & signals
We have always had softe in pt_regs, and accessible via PT_SOFTE, even
though it is not userspace state.

The value userspace sees should always be 1, because we should never
be in userspace with interrupts soft disabled.

In a subsequent patch we will be changing the semantics of the kernel
softe value, so hard wire the value to 1 to retain the existing
semantics. As far as we know nothing ever looks at it, but better safe
than sorry.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
[mpe: Split out of larger patch, write change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:54 +11:00
Gustavo Romero c1fa0768a8 powerpc/tm: Flush TM only if CPU has TM feature
Commit cd63f3c ("powerpc/tm: Fix saving of TM SPRs in core dump")
added code to access TM SPRs in flush_tmregs_to_thread(). However
flush_tmregs_to_thread() does not check if TM feature is available on
CPU before trying to access TM SPRs in order to copy live state to
thread structures. flush_tmregs_to_thread() is indeed guarded by
CONFIG_PPC_TRANSACTIONAL_MEM but it might be the case that kernel
was compiled with CONFIG_PPC_TRANSACTIONAL_MEM enabled and ran on
a CPU without TM feature available, thus rendering the execution
of TM instructions that are treated by the CPU as illegal instructions.

The fix is just to add proper checking in flush_tmregs_to_thread()
if CPU has the TM feature before accessing any TM-specific resource,
returning immediately if TM is no available on the CPU. Adding
that checking in flush_tmregs_to_thread() instead of in places
where it is called, like in vsr_get() and vsr_set(), is better because
avoids the same problem cropping up elsewhere.

Cc: stable@vger.kernel.org # v4.13+
Fixes: cd63f3c ("powerpc/tm: Fix saving of TM SPRs in core dump")
Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-20 13:30:09 +10:00
Masahiro Yamada 7f2462acb6 powerpc: Squash lines for simple wrapper functions
Remove unneeded variables and assignments.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:42 +10:00
Gustavo Romero cd63f3cf1d powerpc/tm: Fix saving of TM SPRs in core dump
Currently flush_tmregs_to_thread() does not save the TM SPRs (TFHAR,
TFIAR, TEXASR) to the thread struct, unless the process is currently
inside a suspended transaction.

If the process is core dumping, and the TM SPRs have changed since the
last time the process was context switched, then we will save stale
values of the TM SPRs to the core dump.

Fix it by saving the live register state to the thread struct in that
case.

Fixes: 08e1c01d6a ("powerpc/ptrace: Enable support for TM SPR state")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-28 15:56:06 +10:00
Dave Martin b34ca60148 powerpc/ptrace: Preserve previous TM fprs/vsrs on short regset write
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET
to fill all the check pointed registers, the thread's old check pointed
registers are preserved.

Fixes: 9d3918f7c0 ("powerpc/ptrace: Enable support for NT_PPC_CVSX")
Fixes: 19cbcbf75a ("powerpc/ptrace: Enable support for NT_PPC_CFPR")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-20 14:55:19 +11:00
Dave Martin 99dfe80a2a powerpc/ptrace: Preserve previous fprs/vsrs on short regset write
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET
to fill all the registers, the thread's old registers are preserved.

Fixes: c6e6771b87 ("powerpc: Introduce VSX thread_struct and CONFIG_VSX")
Cc: stable@vger.kernel.org # v2.6.27+
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-20 14:54:43 +11:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Cyril Bur 000ec280e3 powerpc: tm: Rename transct_(*) to ck(\1)_state
Make the structures being used for checkpointed state named
consistently with the pt_regs/ckpt_regs.

Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-04 20:33:16 +11:00
Cyril Bur dc3106690b powerpc: tm: Always use fp_state and vr_state to store live registers
There is currently an inconsistency as to how the entire CPU register
state is saved and restored when a thread uses transactional memory
(TM).

Using transactional memory results in the CPU having duplicated
(almost) all of its register state. This duplication results in a set
of registers which can be considered 'live', those being currently
modified by the instructions being executed and another set that is
frozen at a point in time.

On context switch, both sets of state have to be saved and (later)
restored. These two states are often called a variety of different
things. Common terms for the state which only exists after the CPU has
entered a transaction (performed a TBEGIN instruction) in hardware are
'transactional' or 'speculative'.

Between a TBEGIN and a TEND or TABORT (or an event that causes the
hardware to abort), regardless of the use of TSUSPEND the
transactional state can be referred to as the live state.

The second state is often to referred to as the 'checkpointed' state
and is a duplication of the live state when the TBEGIN instruction is
executed. This state is kept in the hardware and will be rolled back
to on transaction failure.

Currently all the registers stored in pt_regs are ALWAYS the live
registers, that is, when a thread has transactional registers their
values are stored in pt_regs and the checkpointed state is in
ckpt_regs. A strange opposite is true for fp_state/vr_state. When a
thread is non transactional fp_state/vr_state holds the live
registers. When a thread has initiated a transaction fp_state/vr_state
holds the checkpointed state and transact_fp/transact_vr become the
structure which holds the live state (at this point it is a
transactional state).

This method creates confusion as to where the live state is, in some
circumstances it requires extra work to determine where to put the
live state and prevents the use of common functions designed (probably
before TM) to save the live state.

With this patch pt_regs, fp_state and vr_state all represent the
same thing and the other structures [pending rename] are for
checkpointed state.

Acked-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-04 20:33:15 +11:00
Simon Guo 261831160d powerpc/ptrace: Fix cppcheck issue in gpr32_set_common/gpr32_get_common()
The ckpt_regs usage in gpr32_set_common/gpr32_get_common() will lead to
following cppcheck error at ifndef CONFIG_PPC_TRANSACTIONAL_MEM case:

[arch/powerpc/kernel/ptrace.c:2062]:
(error) Uninitialized variable: ckpt_regs
[arch/powerpc/kernel/ptrace.c:2130]:
(error) Uninitialized variable: ckpt_regs

The problem is due to gpr32_set_common() used ckpt_regs variable which
only makes sense at #ifdef CONFIG_PPC_TRANSACTIONAL_MEM.

This patch fix this issue by passing in "regs" parameter instead.

Reported-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-09-13 17:37:12 +10:00
Daniel Axtens 0545d5436a powerpc/sparse: Add more assembler prototypes
Another set of things that are only called from assembler and so need
prototypes to keep sparse happy.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-09-13 17:36:58 +10:00
Cyril Bur c7a318ba86 powerpc/ptrace: Fix coredump since ptrace TM changes
Commit 8d460f6156 ("powerpc/process: Add the function
flush_tmregs_to_thread") added flush_tmregs_to_thread() and included
the assumption that it would only be called for a task which is not
current.

Although this is correct for ptrace, when generating a core dump, some
of the routines which call flush_tmregs_to_thread() are called. This
leads to a WARNing such as:

  Not expecting ptrace on self: TM regs may be incorrect
  ------------[ cut here ]------------
  WARNING: CPU: 123 PID: 7727 at arch/powerpc/kernel/process.c:1088 flush_tmregs_to_thread+0x78/0x80
  CPU: 123 PID: 7727 Comm: libvirtd Not tainted 4.8.0-rc1-gcc6x-g61e8a0d 
  task: c000000fe631b600 task.stack: c000000fe63b0000
  NIP: c00000000001a1a8 LR: c00000000001a1a4 CTR: c000000000717780
  REGS: c000000fe63b3420 TRAP: 0700   Not tainted  (4.8.0-rc1-gcc6x-g61e8a0d)
  MSR: 900000010282b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE,TM[E]>  CR: 28004222  XER: 20000000
  ...
  NIP [c00000000001a1a8] flush_tmregs_to_thread+0x78/0x80
  LR [c00000000001a1a4] flush_tmregs_to_thread+0x74/0x80
  Call Trace:
   flush_tmregs_to_thread+0x74/0x80 (unreliable)
   vsr_get+0x64/0x1a0
   elf_core_dump+0x604/0x1430
   do_coredump+0x5fc/0x1200
   get_signal+0x398/0x740
   do_signal+0x54/0x2b0
   do_notify_resume+0x98/0xb0
   ret_from_except_lite+0x70/0x74

So fix flush_tmregs_to_thread() to detect the case where it is called on
current, and a transaction is active, and in that case flush the TM regs
to the thread_struct.

This patch also moves flush_tmregs_to_thread() into ptrace.c as it is
only called from that file.

Fixes: 8d460f6156 ("powerpc/process: Add the function flush_tmregs_to_thread")
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
[mpe: Flesh out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-10 16:34:20 +10:00
Anshuman Khandual a67ae75802 powerpc/ptrace: Enable support for Performance Monitor registers
This patch enables support for Performance monitor registers related
ELF core note NT_PPC_PMU based ptrace requests through
PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved
through adding one new register sets REGSET_PMU in powerpc
corresponding to the ELF core note sections added in this
regard. It also implements the get, set and active functions
for this new register sets added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:24 +10:00
Anshuman Khandual cf89d4e1b1 powerpc/ptrace: Enable support for EBB registers
This patch enables support for EBB state registers related
ELF core note NT_PPC_EBB based ptrace requests through
PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved
through adding one new register sets REGSET_EBB in powerpc
corresponding to the ELF core note sections added in this
regard. It also implements the get, set and active functions
for this new register sets added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:23 +10:00
Anshuman Khandual fa439810cc powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR
This patch enables support for running TAR, PPR, DSCR registers
related ELF core notes NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR based
ptrace requests through PTRACE_GETREGSET, PTRACE_SETREGSET calls.
This is achieved through adding three new register sets REGSET_TAR,
REGSET_PPR, REGSET_DSCR in powerpc corresponding to the ELF core
note sections added in this regad. It implements the get, set and
active functions for all these new register sets added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:22 +10:00
Anshuman Khandual c45dc9003a powerpc/ptrace: Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR
This patch enables support for all three TM checkpointed SPR
states related ELF core note  NT_PPC_TM_CTAR, NT_PPC_TM_CPPR,
NT_PPC_TM_CDSCR based ptrace requests through PTRACE_GETREGSET,
PTRACE_SETREGSET calls. This is achieved through adding three
new register sets REGSET_TM_CTAR, REGSET_TM_CPPR and
REGSET_TM_CDSCR in powerpc corresponding to the ELF core note
sections added. It implements the get, set and active functions
for all these new register sets added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:22 +10:00
Anshuman Khandual 08e1c01d6a powerpc/ptrace: Enable support for TM SPR state
This patch enables support for TM SPR state related ELF core
note NT_PPC_TM_SPR based ptrace requests through PTRACE_GETREGSET,
PTRACE_SETREGSET calls. This is achieved through adding a register
set REGSET_TM_SPR in powerpc corresponding to the ELF core note
section added. It implements the get, set and active functions for
this new register set added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:21 +10:00
Anshuman Khandual 9d3918f7c0 powerpc/ptrace: Enable support for NT_PPC_CVSX
This patch enables support for TM checkpointed VSX register
set ELF core note NT_PPC_CVSX based ptrace requests through
PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved
through adding a register set REGSET_CVSX in powerpc
corresponding to the ELF core note section added. It
implements the get, set and active functions for this new
register set added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:20 +10:00
Anshuman Khandual 8c13f59999 powerpc/ptrace: Enable support for NT_PPC_CVMX
This patch enables support for TM checkpointed VMX register
set ELF core note NT_PPC_CVMX based ptrace requests through
PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved
through adding a register set REGSET_CVMX in powerpc
corresponding to the ELF core note section added. It
implements the get, set and active functions for this new
register set added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:19 +10:00
Anshuman Khandual 19cbcbf75a powerpc/ptrace: Enable support for NT_PPC_CFPR
This patch enables support for TM checkpointed FPR register
set ELF core note NT_PPC_CFPR based ptrace requests through
PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved
through adding a register set REGSET_CFPR in powerpc
corresponding to the ELF core note section added. It
implements the get, set and active functions for this new
register set added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:19 +10:00
Anshuman Khandual 25847fb195 powerpc/ptrace: Enable support for NT_PPC_CGPR
This patch enables support for TM checkpointed GPR register
set ELF core note NT_PPC_CGPR based ptrace requests through
PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved
through adding a register set REGSET_CGPR in powerpc
corresponding to the ELF core note section added. It
implements the get, set and active functions for this new
register set added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:18 +10:00
Anshuman Khandual 04fcadce0e powerpc/ptrace: Adapt gpr32_get, gpr32_set functions for transaction
This patch splits gpr32_get, gpr32_set functions to accommodate
in transaction ptrace requests implemented in patches later in
the series.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:17 +10:00
Anshuman Khandual 94b7d3610e powerpc/ptrace: Enable in transaction NT_PPC_VSX ptrace requests
This patch enables in transaction NT_PPC_VSX ptrace requests. The
function vsr_get which gets the running value of all VSX registers
and the function vsr_set which sets the running value of of all VSX
registers work on the running set of VMX registers whose location
will be different if transaction is active. This patch makes these
functions adapt to situations when the transaction is active.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:17 +10:00
Anshuman Khandual d844e27915 powerpc/ptrace: Enable in transaction NT_PPC_VMX ptrace requests
This patch enables in transaction NT_PPC_VMX ptrace requests. The
function vr_get which gets the running value of all VMX registers
and the function vr_set which sets the running value of of all VMX
registers work on the running set of VMX registers whose location
will be different if transaction is active. This patch makes these
functions adapt to situations when the transaction is active.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:16 +10:00
Anshuman Khandual 1ec8549d44 powerpc/ptrace: Enable in transaction NT_PRFPREG ptrace requests
This patch enables in transaction NT_PRFPREG ptrace requests.
The function fpr_get which gets the running value of all FPR
registers and the function fpr_set which sets the running
value of of all FPR registers work on the running set of FPR
registers whose location will be different if transaction is
active. This patch makes these functions adapt to situations
when the transaction is active.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:15 +10:00
Linus Torvalds 7a1e8b80fb Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Highlights:

   - TPM core and driver updates/fixes
   - IPv6 security labeling (CALIPSO)
   - Lots of Apparmor fixes
   - Seccomp: remove 2-phase API, close hole where ptrace can change
     syscall #"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (156 commits)
  apparmor: fix SECURITY_APPARMOR_HASH_DEFAULT parameter handling
  tpm: Add TPM 2.0 support to the Nuvoton i2c driver (NPCT6xx family)
  tpm: Factor out common startup code
  tpm: use devm_add_action_or_reset
  tpm2_i2c_nuvoton: add irq validity check
  tpm: read burstcount from TPM_STS in one 32-bit transaction
  tpm: fix byte-order for the value read by tpm2_get_tpm_pt
  tpm_tis_core: convert max timeouts from msec to jiffies
  apparmor: fix arg_size computation for when setprocattr is null terminated
  apparmor: fix oops, validate buffer size in apparmor_setprocattr()
  apparmor: do not expose kernel stack
  apparmor: fix module parameters can be changed after policy is locked
  apparmor: fix oops in profile_unpack() when policy_db is not present
  apparmor: don't check for vmalloc_addr if kvzalloc() failed
  apparmor: add missing id bounds check on dfa verification
  apparmor: allow SYS_CAP_RESOURCE to be sufficient to prlimit another task
  apparmor: use list_next_entry instead of list_entry_next
  apparmor: fix refcount race when finding a child profile
  apparmor: fix ref count leak when profile sha1 hash is read
  apparmor: check that xindex is in trans_table bounds
  ...
2016-07-29 17:38:46 -07:00
Kees Cook 1addc57e11 powerpc/ptrace: run seccomp after ptrace
Close the hole where ptrace can change a syscall out from under seccomp.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
2016-06-14 10:54:46 -07:00
Andy Lutomirski 2f275de5d1 seccomp: Add a seccomp_data parameter secure_computing()
Currently, if arch code wants to supply seccomp_data directly to
seccomp (which is generally much faster than having seccomp do it
using the syscall_get_xyz() API), it has to use the two-phase
seccomp hooks. Add it to the easy hooks, too.

Cc: linux-arch@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-06-14 10:54:39 -07:00
Khem Raj 1e407ee3b2 powerpc/ptrace: Fix out of bounds array access warning
gcc-6 correctly warns about a out of bounds access

arch/powerpc/kernel/ptrace.c:407:24: warning: index 32 denotes an offset greater than size of 'u64[32][1] {aka long long unsigned int[32][1]}' [-Warray-bounds]
        offsetof(struct thread_fp_state, fpr[32][0]));
                        ^

check the end of array instead of beginning of next element to fix this

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-06 10:48:07 +10:00
Rashmica Gupta 343c3327c1 powerpc: Add rN aliases to the pt_regs_offset table.
It is common practice with powerpc to use 'rN' to refer to register 'N'. However
when using the pt_regs_offset table we have to use 'gprN'.

So add aliases such that both 'rN' and 'gprN' can be used.

For example, we can currently do:
  $ su -
  $ cd /sys/kernel/debug/tracing
  $ echo "p:probe/sys_fchownat sys_fchownat %gpr3:s32 +0(%gpr4):string %gpr5:s32 %gpr6:s32 %gpr7:s32" > kprobe_events
  $ echo 1 > events/probe/sys_fchownat/enable
  $ touch /tmp/foo
  $ chown root /tmp/foo
  $ echo 0 > events/enable
  $ cat trace
    chown-2925  [014] d...    76.160657: sys_fchownat: (SyS_fchownat+0x8/0x1a0) arg1=-100 arg2="/tmp/foo" arg3=0 arg4=-1 arg5=0

Instead we'd like to be able to use:
 $ echo "p:probe/sys_fchownat sys_fchownat %r3:s32 +0(%r4):string %r5:s32 %r6:s32 %r7:s32" > kprobe_events

Signed-off-by: Rashmica Gupta <rashmicy@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-26 22:11:17 +11:00
Michael Ellerman 2449acc534 powerpc/kernel: Enable seccomp filter
This commit enables seccomp filter on powerpc, now that we have all the
necessary pieces in place.

To support seccomp's desire to modify the syscall return value under
some circumstances, we use a different ABI to the ptrace ABI. That is we
use r3 as the syscall return value, and orig_gpr3 is the first syscall
parameter.

This means the seccomp code, or a ptracer via SECCOMP_RET_TRACE, will
see -ENOSYS preloaded in r3. This is identical to the behaviour on x86,
and allows seccomp or the ptracer to either leave the -ENOSYS or change
it to something else, as well as rejecting or not the syscall by
modifying r0.

If seccomp does not reject the syscall, we restore the register state to
match what ptrace and audit expect, ie. r3 is the first syscall
parameter again. We do this restore using orig_gpr3, which may have been
modified by seccomp, which allows seccomp to modify the first syscall
paramater and allow the syscall to proceed.

We need to #ifdef the the additional handling of r3 for seccomp, so move
it all out of line.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Kees Cook <keescook@chromium.org>
2015-07-30 14:34:44 +10:00
Michael Ellerman d38374142b powerpc/kernel: Change the do_syscall_trace_enter() API
The API for calling do_syscall_trace_enter() is currently sensible
enough, it just returns the (modified) syscall number.

However once we enable seccomp filter it will get more complicated. When
seccomp filter runs, the seccomp kernel code (via SECCOMP_RET_ERRNO), or
a ptracer (via SECCOMP_RET_TRACE), may reject the syscall and *may* or may
*not* set a return value in r3.

That means the assembler that calls do_syscall_trace_enter() can not
blindly return ENOSYS, it needs to only return ENOSYS if a return value
has not already been set.

There is no way to implement that logic with the current API. So change
the do_syscall_trace_enter() API to make it deal with the return code
juggling, and the assembler can then just return whatever return code it
is given.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Kees Cook <keescook@chromium.org>
2015-07-29 11:56:11 +10:00
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
Anton Blanchard e51df2c170 powerpc: Make a bunch of things static
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25 23:14:41 +10:00
Eric Paris 91397401bb ARCH: AUDIT: audit_syscall_entry() should not require the arch
We have a function where the arch can be queried, syscall_get_arch().
So rather than have every single piece of arch specific code use and/or
duplicate syscall_get_arch(), just have the audit code use the
syscall_get_arch() code.

Based-on-patch-by: Richard Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: linux-mips@linux-mips.org
Cc: linux@lists.openrisc.net
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: linux-xtensa@linux-xtensa.org
Cc: x86@kernel.org
2014-09-23 16:21:26 -04:00
Ulrich Weigand 36aa1b180e powerpc: PTRACE_PEEKUSR always returns FPR0
There is a bug in using ptrace to access FPRs via PTRACE_PEEKUSR /
PTRACE_POKEUSR. In effect, trying to access any of the FPRs always
really accesses FPR0, which does seriously break debugging :-)

The problem seems to have been introduced by commit 3ad26e5c44
(Merge branch 'for-kvm' into next).

[ It is indeed a merge conflict between Paul's FPU/VSX state rework
and my LE patches - Anton ]

Signed-off-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-13 15:48:33 +11:00
Suzuki Poulose a0b38b4e78 powerpc: Set the NOTE type for SPE regset
The regset defintion for SPE doesn't have the core_note_type
set, which prevents it from being dumped. Add the note type
NT_PPC_SPE for SPE regset.

Signed-off-by: Suzuki K Poulose <suzuki@in.ibm.com>
Cc: Roland McGrath <roland@hack.frob.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2013-10-28 21:11:16 -05:00