linux/kernel/events
Will Deacon 88b0193d94 perf/callchain: Force USER_DS when invoking perf_callchain_user()
Perf can generate and record a user callchain in response to a synchronous
request, such as a tracepoint firing. If this happens under set_fs(KERNEL_DS),
then we can end up walking the user stack (and dereferencing/saving whatever we
find there) without the protections usually afforded by checks such as
access_ok.

Rather than play whack-a-mole with each architecture's stack unwinding
implementation, fix the root of the problem by ensuring that we force USER_DS
when invoking perf_callchain_user from the perf core.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-10 07:54:00 +02:00
..
Makefile ftrace: allow architectures to specify ftrace compile options 2015-01-29 09:19:19 +01:00
callchain.c perf/callchain: Force USER_DS when invoking perf_callchain_user() 2017-05-10 07:54:00 +02:00
core.c Merge branch 'perf/urgent' into perf/core, to pick up fixes 2017-03-28 07:44:25 +02:00
hw_breakpoint.c perf: Collapse and fix event_function_call() users 2016-01-21 18:54:24 +01:00
internal.h bpf, events: fix offset in skb copy handler 2016-07-25 10:34:11 -07:00
ring_buffer.c perf/core: Add a flag for partial AUX records 2017-03-16 09:51:11 +01:00
uprobes.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/coredump.h> 2017-03-02 08:42:28 +01:00