[PATCH 05/25] perf trace: Fix potential NULL pointer dereference found by the smatch tool

Arnaldo Carvalho de Melo
2019-07-09T18:32:11Z

From: Leo Yan <leo.yan@linaro.org>

Based on the following report from Smatch, fix the potential NULL
pointer dereference check.

tools/perf/builtin-trace.c:1044
thread_trace__new() error: we previously assumed 'ttrace' could be
null (see line 1041).

tools/perf/builtin-trace.c
1037 static struct thread_trace *thread_trace__new(void)
1038 {
1039 struct thread_trace *ttrace = zalloc(sizeof(struct thread_trace));
1040
1041 if (ttrace)
1042 ttrace->files.max = -1;
1043
1044 ttrace->syscall_stats = intlist__new(NULL);
^^^^^^^^
1045
1046 return ttrace;
1047 }

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Alexios Zavras <alexios.zavras@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Changbin Du <changbin.du@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Song Liu <songliubraving@fb.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190702103420.27540-6-leo.yan@linaro.org
[ Just made it look like other tools/perf constructors, same end result ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-trace.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index d0eb7224dd36..e3fc9062f136 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -1038,10 +1038,10 @@ static struct thread_trace *thread_trace__new(void)
{
struct thread_trace *ttrace = zalloc(sizeof(struct thread_trace));

- if (ttrace)
+ if (ttrace) {
ttrace->files.max = -1;
-
- ttrace->syscall_stats = intlist__new(NULL);
+ ttrace->syscall_stats = intlist__new(NULL);
+ }

return ttrace;
}
--
2.21.0