Commit-ID: f3c8d90757724982e5f07cd77d315eb64ca145ac Gitweb: https://git.kernel.org/tip/f3c8d90757724982e5f07cd77d315eb64ca145ac Author: Leo Yan <leo....@linaro.org> AuthorDate: Tue, 2 Jul 2019 18:34:17 +0800 Committer: Arnaldo Carvalho de Melo <a...@redhat.com> CommitDate: Tue, 9 Jul 2019 09:33:55 -0300
perf session: Fix potential NULL pointer dereference found by the smatch tool Based on the following report from Smatch, fix the potential NULL pointer dereference check. tools/perf/util/session.c:1252 dump_read() error: we previously assumed 'evsel' could be null (see line 1249) tools/perf/util/session.c 1240 static void dump_read(struct perf_evsel *evsel, union perf_event *event) 1241 { 1242 struct read_event *read_event = &event->read; 1243 u64 read_format; 1244 1245 if (!dump_trace) 1246 return; 1247 1248 printf(": %d %d %s %" PRIu64 "\n", event->read.pid, event->read.tid, 1249 evsel ? perf_evsel__name(evsel) : "FAIL", 1250 event->read.value); 1251 1252 read_format = evsel->attr.read_format; ^^^^^^^ 'evsel' could be NULL pointer, for this case this patch directly bails out without dumping read_event. Signed-off-by: Leo Yan <leo....@linaro.org> Acked-by: Jiri Olsa <jo...@kernel.org> Cc: Adrian Hunter <adrian.hun...@intel.com> Cc: Alexander Shishkin <alexander.shish...@linux.intel.com> Cc: Alexey Budankov <alexey.budan...@linux.intel.com> Cc: Alexios Zavras <alexios.zav...@intel.com> Cc: Andi Kleen <a...@linux.intel.com> Cc: Changbin Du <changbin...@intel.com> Cc: David S. Miller <da...@davemloft.net> Cc: Davidlohr Bueso <d...@stgolabs.net> Cc: Eric Saint-Etienne <eric.saint.etie...@oracle.com> Cc: Jin Yao <yao....@linux.intel.com> Cc: Konstantin Khlebnikov <khlebni...@yandex-team.ru> Cc: Mathieu Poirier <mathieu.poir...@linaro.org> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Rasmus Villemoes <li...@rasmusvillemoes.dk> Cc: Song Liu <songliubrav...@fb.com> Cc: Suzuki Poulouse <suzuki.poul...@arm.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Thomas Richter <tmri...@linux.ibm.com> Cc: linux-arm-ker...@lists.infradead.org Link: http://lkml.kernel.org/r/20190702103420.27540-9-leo....@linaro.org Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/util/session.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index 54cf163347f7..2e61dd6a3574 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -1249,6 +1249,9 @@ static void dump_read(struct perf_evsel *evsel, union perf_event *event) evsel ? perf_evsel__name(evsel) : "FAIL", event->read.value); + if (!evsel) + return; + read_format = evsel->attr.read_format; if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)