[tip:perf/urgent] perf record: Fix segfault with --no-mmap-pages

[tip-bot for David Ahern <tipbot@zytor.com>]

Commit-ID:  8973504be70b2986a2081eeff7d9a4210dec295d
Gitweb:     http://git.kernel.org/tip/8973504be70b2986a2081eeff7d9a4210dec295d
Author:     David Ahern <dsahern@gmail.com>
AuthorDate: Tue, 12 Nov 2013 07:46:53 -0700
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 12 Nov 2013 16:30:54 -0300

perf record: Fix segfault with --no-mmap-pages

Adrian reported a segfault when using --no-out-pages:

$ tools/perf/perf record -vv --no-out-pages uname
Segmentation fault (core dumped)

The same occurs with --no-mmap-pages. Fix by checking that str is
non-NULL before parsing it.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1384267617-3446-2-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/evlist.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 99dc58e..3960560 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -719,6 +719,9 @@ int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
 		{ .tag  = 0 },
 	};
 
+	if (str == NULL)
+		return -1;
+
 	val = parse_tag_value(str, tags);
 	if (val != (unsigned long) -1) {
 		/* we got file size value */