perf/x86/intel/uncore: Make sure only uncore events are collected
authorJiri Olsa <jolsa@kernel.org>
Wed, 10 Dec 2014 20:23:50 +0000 (21:23 +0100)
committerIngo Molnar <mingo@kernel.org>
Thu, 11 Dec 2014 10:24:14 +0000 (11:24 +0100)
commitaf91568e762d04931dcbdd6bef4655433d8b9418
tree2a2924dfc908ec50ebeb94a9e9840272676592f3
parent201e7deb9062bb9a8a5bc113e36457c3ff55b226
perf/x86/intel/uncore: Make sure only uncore events are collected

The uncore_collect_events functions assumes that event group
might contain only uncore events which is wrong, because it
might contain any type of events.

This bug leads to uncore framework touching 'not' uncore events,
which could end up all sorts of bugs.

One was triggered by Vince's perf fuzzer, when the uncore code
touched breakpoint event private event space as if it was uncore
event and caused BUG:

   BUG: unable to handle kernel paging request at ffffffff82822068
   IP: [<ffffffff81020338>] uncore_assign_events+0x188/0x250
   ...

The code in uncore_assign_events() function was looking for
event->hw.idx data while the event was initialized as a
breakpoint with different members in event->hw union.

This patch forces uncore_collect_events() to collect only uncore
events.

Reported-by: Vince Weaver <vince@deater.net>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yan, Zheng <zheng.z.yan@intel.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1418243031-20367-2-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/kernel/cpu/perf_event_intel_uncore.c