[PATCH AUTOSEL 5.2 123/171] perf stat: Fix use-after-freed pointer detected by the smatch tool

[Sasha Levin]

From: Leo Yan <leo.yan@xxxxxxxxxx>

[ Upstream commit c74b05030edb3b52f4208d8415b8c933bc509a29 ]

Based on the following report from Smatch, fix the use-after-freed
pointer.

  tools/perf/builtin-stat.c:1353
  add_default_attributes() warn: passing freed memory 'str'.

The pointer 'str' has been freed but later it is still passed into the
function parse_events_print_error().  This patch fixes this
use-after-freed issue.

Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
Cc: Alexios Zavras <alexios.zavras@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Changbin Du <changbin.du@xxxxxxxxx>
Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Eric Saint-Etienne <eric.saint.etienne@xxxxxxxxxx>
Cc: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
Cc: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Cc: Song Liu <songliubraving@xxxxxx>
Cc: Suzuki Poulouse <suzuki.poulose@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Thomas Richter <tmricht@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20190702103420.27540-3-leo.yan@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 tools/perf/builtin-stat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 1ae66f09dc7d..e28002d90573 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -1276,8 +1276,8 @@ static int add_default_attributes(void)
 				fprintf(stderr,
 					"Cannot set up top down events %s: %d\n",
 					str, err);
-				free(str);
 				parse_events_print_error(&errinfo, str);
+				free(str);
 				return -1;
 			}
 		} else {
-- 
2.20.1