linux-stable.git/kernel, branch linux-3.2.y

tracing: probeevent: Fix to support minus offset from symbol

2018-05-31T23:30:24+00:00

commit c5d343b6b7badd1f5fe0873eff2e8d63a193e732 upstream.

In Documentation/trace/kprobetrace.txt, it says

 @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)

However, the parser doesn't parse minus offset correctly, since
commit 2fba0c8867af ("tracing/kprobes: Fix probe offset to be
unsigned") drops minus ("-") offset support for kprobe probe
address usage.

This fixes the traceprobe_split_symbol_offset() to parse minus
offset again with checking the offset range, and add a minus
offset check in kprobe probe address usage.

Link: http://lkml.kernel.org/r/152129028983.31874.13419301530285775521.stgit@devbox

Cc: Ingo Molnar 
Cc: Tom Zanussi 
Cc: Arnaldo Carvalho de Melo 
Cc: Ravi Bangoria 
Fixes: 2fba0c8867af ("tracing/kprobes: Fix probe offset to be unsigned")
Acked-by: Namhyung Kim 
Signed-off-by: Masami Hiramatsu 
Signed-off-by: Steven Rostedt (VMware) 
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings

posix-timers: Protect posix clock array access against speculation

2018-05-31T23:30:24+00:00

commit 19b558db12f9f4e45a22012bae7b4783e62224da upstream.

The clockid argument of clockid_to_kclock() comes straight from user space
via various syscalls and is used as index into the posix_clocks array.

Protect it against spectre v1 array out of bounds speculation. Remove the
redundant check for !posix_clock[id] as this is another source for
speculation and does not provide any advantage over the return
posix_clock[id] path which returns NULL in that case anyway.

Signed-off-by: Thomas Gleixner 
Acked-by: Peter Zijlstra (Intel) 
Acked-by: Dan Williams 
Cc: Rasmus Villemoes 
Cc: Greg KH 
Cc: Linus Torvalds 
Cc: David Woodhouse 
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1802151718320.1296@nanos.tec.linutronix.de
[bwh: Backported to 3.2:
 - Move the test of the clock_getres field below the lookup using
   array_index_nospec()
 - Adjust filename, context]
Signed-off-by: Ben Hutchings

kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE

2018-05-31T23:30:17+00:00

commit 88913bd8ea2a75d7e460a4bed5f75e1c32660d7e upstream.

chan->n_subbufs is set by the user and relay_create_buf() does a kmalloc()
of chan->n_subbufs * sizeof(size_t *).

kmalloc_slab() will generate a warning when this fails if
chan->subbufs * sizeof(size_t *) > KMALLOC_MAX_SIZE.

Limit chan->n_subbufs to the maximum allowed kmalloc() size.

Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802061216100.122576@chino.kir.corp.google.com
Fixes: f6302f1bcd75 ("relay: prevent integer overflow in relay_open()")
Signed-off-by: David Rientjes 
Reviewed-by: Andrew Morton 
Cc: Jens Axboe 
Cc: Dave Jiang 
Cc: Al Viro 
Cc: Dan Carpenter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Ben Hutchings

hrtimer: Ensure POSIX compliance (relative CLOCK_REALTIME hrtimers)

2018-05-31T23:30:08+00:00

commit 48d0c9becc7f3c66874c100c126459a9da0fdced upstream.

The POSIX specification defines that relative CLOCK_REALTIME timers are not
affected by clock modifications. Those timers have to use CLOCK_MONOTONIC
to ensure POSIX compliance.

The introduction of the additional HRTIMER_MODE_PINNED mode broke this
requirement for pinned timers.

There is no user space visible impact because user space timers are not
using pinned mode, but for consistency reasons this needs to be fixed.

Check whether the mode has the HRTIMER_MODE_REL bit set instead of
comparing with HRTIMER_MODE_ABS.

Signed-off-by: Anna-Maria Gleixner 
Cc: Christoph Hellwig 
Cc: John Stultz 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: keescook@chromium.org
Fixes: 597d0275736d ("timers: Framework for identifying pinned timers")
Link: http://lkml.kernel.org/r/20171221104205.7269-7-anna-maria@linutronix.de
Signed-off-by: Ingo Molnar 
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings

perf/hwbp: Simplify the perf-hwbp code, fix documentation

2018-05-31T23:30:04+00:00

commit f67b15037a7a50c57f72e69a6d59941ad90a0f0f upstream.

Annoyingly, modify_user_hw_breakpoint() unnecessarily complicates the
modification of a breakpoint - simplify it and remove the pointless
local variables.

Also update the stale Docbook while at it.

Signed-off-by: Linus Torvalds 
Acked-by: Thomas Gleixner 
Cc: Alexander Shishkin 
Cc: Andy Lutomirski 
Cc: Arnaldo Carvalho de Melo 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Vince Weaver 
Signed-off-by: Ingo Molnar 
Signed-off-by: Ben Hutchings

perf/hwpb: Invoke __perf_event_disable() if interrupts are already disabled

2018-05-31T23:30:04+00:00

commit 500ad2d8b01390c98bc6dce068bccfa9534b8212 upstream.

While debugging a warning message on PowerPC while using hardware
breakpoints, it was discovered that when perf_event_disable is invoked
through hw_breakpoint_handler function with interrupts disabled, a
subsequent IPI in the code path would trigger a WARN_ON_ONCE message in
smp_call_function_single function.

This patch calls __perf_event_disable() when interrupts are already
disabled, instead of perf_event_disable().

Reported-by: Edjunior Barbosa Machado 
Signed-off-by: K.Prasad 
[naveen.n.rao@linux.vnet.ibm.com: v3: Check to make sure we target current task]
Signed-off-by: Naveen N. Rao 
Acked-by: Frederic Weisbecker 
Signed-off-by: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20120802081635.5811.17737.stgit@localhost.localdomain
[ Fixed build error on MIPS. ]
Signed-off-by: Ingo Molnar 
Signed-off-by: Ben Hutchings

module/retpoline: Warn about missing retpoline in module

2018-03-19T18:58:35+00:00

commit caf7501a1b4ec964190f31f9c3f163de252273b8 upstream.

There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.

To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.

If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.

[ tglx: Massaged changelog ]

Signed-off-by: Andi Kleen 
Signed-off-by: Thomas Gleixner 
Cc: David Woodhouse 
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
Signed-off-by: Ben Hutchings

kprobes/x86: Blacklist indirect thunk functions for kprobes

2018-03-19T18:58:33+00:00

commit c1804a236894ecc942da7dc6c5abe209e56cba93 upstream.

Mark __x86_indirect_thunk_* functions as blacklist for kprobes
because those functions can be called from anywhere in the kernel
including blacklist functions of kprobes.

Signed-off-by: Masami Hiramatsu 
Signed-off-by: Thomas Gleixner 
Acked-by: David Woodhouse 
Cc: Andi Kleen 
Cc: Peter Zijlstra 
Cc: Ananth N Mavinakayanahalli 
Cc: Arjan van de Ven 
Cc: Greg Kroah-Hartman 
Link: https://lkml.kernel.org/r/151629209111.10241.5444852823378068683.stgit@devbox
[bwh: Backported to 3.2: We don't have _ASM_NOKPROBE etc., so add indirect
 thunks to the built-in blacklist]
Signed-off-by: Ben Hutchings

gcov: add support for GCC 4.9

2018-03-19T18:58:23+00:00

commit a992bf836f9c3039a16f4bd068d161c86c6c3e2c upstream.

This patch handles the gcov-related changes in GCC 4.9:

  A new counter (time profile) is added. The total number is 9 now.

  A new profile merge function __gcov_merge_time_profile is added.

See gcc/gcov-io.h and libgcc/libgcov-merge.c

For the first change, the layout of struct gcov_info is affected.

For the second one, a dummy function is added to kernel/gcov/base.c
similarly.

Signed-off-by: Yuan Pengfei 
Acked-by: Peter Oberparleiter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Ben Hutchings

gcov: compile specific gcov implementation based on gcc version

2018-03-19T18:58:23+00:00

commit 17c568d60af5a810208baf116dc174a2005c6c3e upstream.

Compile the correct gcov implementation file for the specific gcc version.

Signed-off-by: Frantisek Hrbata 
Cc: Jan Stancek 
Cc: Kees Cook 
Acked-by: Peter Oberparleiter 
Cc: Rusty Russell 
Cc: Arnd Bergmann 
Cc: Andy Gospodarek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Ben Hutchings