perf session: Fix possible null pointer dereference in session.c

cppcheck detected following warning:
[tools/perf/util/session.c:1628] -> [tools/perf/util/session.c:1632]:
 (warning) Possible null pointer dereference: session - otherwise it
 is redundant to check it against null.

In order to avoide null pointer, check the pointer before use.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Link: http://lkml.kernel.org/r/1400087618-13628-1-git-send-email-standby24x7@gmail.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 55960f22233c..64a186edc7be 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1625,13 +1625,14 @@ out_delete_map:
 void perf_session__fprintf_info(struct perf_session *session, FILE *fp,
                                 bool full)
 {
-        int fd = perf_data_file__fd(session->file);
         struct stat st;
-        int ret;
+        int fd, ret;
 
         if (session == NULL || fp == NULL)
                 return;
 
+        fd = perf_data_file__fd(session->file);
+
         ret = fstat(fd, &st);
         if (ret == -1)
                 return;