[tip:perf/core] perf script: Fix a NULL pointer dereference

[tip-bot for Namhyung Kim <namhyung.kim@lge.com>]

Commit-ID:  d0d3913895e5b50623bd4dafd876e41c1169031d
Gitweb:     http://git.kernel.org/tip/d0d3913895e5b50623bd4dafd876e41c1169031d
Author:     Namhyung Kim <namhyung.kim@lge.com>
AuthorDate: Tue, 14 Aug 2012 10:57:03 +0900
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 14 Aug 2012 10:36:30 -0300

perf script: Fix a NULL pointer dereference

If 'perf script --gen-script' was called with a perf.data which contains
no tracepoint event, it'd segfault due to NULL pevent pointer. Fix it.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1344909423-26384-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/trace-event-parse.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index 4cb7f38..a5a554e 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -293,7 +293,7 @@ struct event_format *trace_find_next_event(struct pevent *pevent,
 {
 	static int idx;
 
-	if (!pevent->events)
+	if (!pevent || !pevent->events)
 		return NULL;
 
 	if (!event) {