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

commit 7d4c85b7035eb2f9ab217ce649dcd1bfaf0cacd3 upstream.

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@vger.kernel.org # v4.4+
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lore.kernel.org/lkml/20190926220018.25402-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/perf/util/llvm-utils.c b/tools/perf/util/llvm-utils.c
index 621f6527b79091eecce238953a4497d14237cc7a..4887dd5eb80fcaf449dc07ec9fef5f573a01505a 100644 (file)
--- a/tools/perf/util/llvm-utils.c
+++ b/tools/perf/util/llvm-utils.c
@@ -220,14 +220,14 @@ 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)