[tip:perf/urgent] perf evlist: Fix for double free in tools/ perf stat

[tip-bot for Yasser Shalabi <tipbot@zytor.com>]

Commit-ID:  b2e19a934a36b2b4affcde9c170c0f01afabe50a
Gitweb:     http://git.kernel.org/tip/b2e19a934a36b2b4affcde9c170c0f01afabe50a
Author:     Yasser Shalabi <yassershalabi@gmail.com>
AuthorDate: Sat, 4 Oct 2014 11:37:57 -0400
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 15 Oct 2014 16:16:53 -0300

perf evlist: Fix for double free in tools/perf stat

Fix for double free bug in tools/perf due to dangling thread_map pointer
in perf_evlist struct.

Code path excercised when perf stat -C switch is used but not set and is
followed by another switch.

Example:

  perf stat -C -e.

Signed-off-by: Yasser Shalabi <yassershalabi@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1412437077-13109-1-git-send-email-yassershalabi@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/evlist.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index b4b54d8..3c9e77d 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1003,6 +1003,7 @@ int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
 
 out_delete_threads:
 	thread_map__delete(evlist->threads);
+	evlist->threads = NULL;
 	return -1;
 }