perf/arm: Fix armpmu_map_hw_event()

commit b88a2595b6d8aedbd275c07dfa784657b4f757eb upstream.

Fix constraint check in armpmu_map_hw_event().

Reported-and-tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 0ea8083..4a2db48 100644 (file)
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -116,7 +116,12 @@ armpmu_map_cache_event(const unsigned (*cache_map)
 static int
 armpmu_map_event(const unsigned (*event_map)[PERF_COUNT_HW_MAX], u64 config)
 {
-       int mapping = (*event_map)[config];
+       int mapping;
+
+       if (config >= PERF_COUNT_HW_MAX)
+               return -ENOENT;
+
+       mapping = (*event_map)[config];
        return mapping == HW_OP_UNSUPPORTED ? -ENOENT : mapping;
 }