[tip:perf/urgent] perf/x86/amd: Set the size of event map array to PERF_COUNT_HW_MAX

From: tip-bot for Adam Borowski
Date: Thu Apr 28 2016 - 04:26:08 EST


Commit-ID: 0a25556f84d5f79e68e9502bb1f32a43377ab2bf
Gitweb: http://git.kernel.org/tip/0a25556f84d5f79e68e9502bb1f32a43377ab2bf
Author: Adam Borowski <kilobyte@xxxxxxxxxx>
AuthorDate: Wed, 27 Apr 2016 11:35:31 +0200
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 28 Apr 2016 10:20:25 +0200

perf/x86/amd: Set the size of event map array to PERF_COUNT_HW_MAX

The entry for PERF_COUNT_HW_REF_CPU_CYCLES is not used on AMD, but is
referenced by filter_events() which expects undefined events to have a
value of 0.

Found via KASAN:

UBSAN: Undefined behaviour in arch/x86/events/amd/core.c:132:30
index 9 is out of range for type 'u64 [9]'
UBSAN: Undefined behaviour in arch/x86/events/amd/core.c:132:9
load of address ffffffff81c021c8 with insufficient space for an object of type 'const u64'

Signed-off-by: Adam Borowski <kilobyte@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vince Weaver <vincent.weaver@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1461749731-30979-1-git-send-email-kilobyte@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/events/amd/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index 86a9bec..bd3e842 100644
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -115,7 +115,7 @@ static __initconst const u64 amd_hw_cache_event_ids
/*
* AMD Performance Monitor K7 and later.
*/
-static const u64 amd_perfmon_event_map[] =
+static const u64 amd_perfmon_event_map[PERF_COUNT_HW_MAX] =
{
[PERF_COUNT_HW_CPU_CYCLES] = 0x0076,
[PERF_COUNT_HW_INSTRUCTIONS] = 0x00c0,