[tip: perf/urgent] perf llvm: Don't access out-of-scope array

[tip-bot2 for Ian Rogers]

The following commit has been merged into the perf/urgent branch of tip:

Commit-ID:     7d4c85b7035eb2f9ab217ce649dcd1bfaf0cacd3
Gitweb:        https://git.kernel.org/tip/7d4c85b7035eb2f9ab217ce649dcd1bfaf0cacd3
Author:        Ian Rogers <irogers@xxxxxxxxxx>
AuthorDate:    Thu, 26 Sep 2019 15:00:18 -07:00
Committer:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitterDate: Mon, 30 Sep 2019 17:29:35 -03:00

perf llvm: Don't access out-of-scope array

The 'test_dir' variable is assigned to the 'release' array which is
out-of-scope 3 lines later.

Extend the scope of the 'release' array so that an out-of-scope array
isn't accessed.

Bug detected by clang's address sanitizer.

Fixes: 07bc5c699a3d ("perf tools: Make fetch_kernel_version() publicly available")
Cc: stable@xxxxxxxxxxxxxxx # v4.4+
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lore.kernel.org/lkml/20190926220018.25402-1-irogers@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/llvm-utils.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/llvm-utils.c b/tools/perf/util/llvm-utils.c
index 8d04e3d..8b14e4a 100644
--- a/tools/perf/util/llvm-utils.c
+++ b/tools/perf/util/llvm-utils.c
@@ -233,14 +233,14 @@ static int detect_kbuild_dir(char **kbuild_dir)
 	const char *prefix_dir = "";
 	const char *suffix_dir = "";
 
+	/* _UTSNAME_LENGTH is 65 */
+	char release[128];
+
 	char *autoconf_path;
 
 	int err;
 
 	if (!test_dir) {
-		/* _UTSNAME_LENGTH is 65 */
-		char release[128];
-
 		err = fetch_kernel_version(NULL, release,
 					   sizeof(release));
 		if (err)