x86, perf: P4 PMU -- check for proper event index in RAW events

RAW events are special and we should be ready for user passing
in insane event index values.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <20100508112717.315897547@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 10 insertions, 1 deletions

diff --git a/arch/x86/kernel/cpu/perf_event_p4.c b/arch/x86/kernel/cpu/perf_event_p4.c
index b8c2d379eea..a603930271f 100644
--- a/arch/x86/kernel/cpu/perf_event_p4.c
+++ b/arch/x86/kernel/cpu/perf_event_p4.c
@@ -418,6 +418,7 @@ static int p4_hw_config(struct perf_event *event)
 {
         int cpu = get_cpu();
         int rc = 0;
+        unsigned int evnt;
         u32 escr, cccr;
 
         /*
@@ -436,6 +437,14 @@ static int p4_hw_config(struct perf_event *event)
                 event->hw.config = p4_set_ht_bit(event->hw.config);
 
         if (event->attr.type == PERF_TYPE_RAW) {
+
+                /* user data may have out-of-bound event index */
+                evnt = p4_config_unpack_event(event->attr.config);
+                if (evnt >= ARRAY_SIZE(p4_event_bind_map)) {
+                        rc = -EINVAL;
+                        goto out;
+                }
+
                 /*
                  * We don't control raw events so it's up to the caller
                  * to pass sane values (and we don't count the thread number
@@ -451,8 +460,8 @@ static int p4_hw_config(struct perf_event *event)
         }
 
         rc = x86_setup_perfctr(event);
+out:
         put_cpu();
-
         return rc;
 }