[PATCH 1/4] perf intel-pt: fix potential NULL pointer dereference in intel_pt_process_auxtrace_info

From: Wen Yang
Date: Wed Nov 21 2018 - 02:39:10 EST


This patch fixes a possible null pointer dereference in
intel_pt_process_auxtrace_info, detected by the semantic patch
deref_null.cocci, with the following warning:

./tools/perf/util/intel-pt.c:2579:32-49: ERROR: session -> itrace_synth_opts is NULL but dereferenced.

Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Reviewed-by: Tan Hu <tan.hu@xxxxxxxxxx>
CC: Julia Lawall <julia.lawall@xxxxxxx>
---
tools/perf/util/intel-pt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
index 149ff36..bac20e8 100644
--- a/tools/perf/util/intel-pt.c
+++ b/tools/perf/util/intel-pt.c
@@ -2575,7 +2575,8 @@ int intel_pt_process_auxtrace_info(union perf_event *event,
if (session->itrace_synth_opts && session->itrace_synth_opts->set) {
pt->synth_opts = *session->itrace_synth_opts;
} else {
- itrace_synth_opts__set_default(&pt->synth_opts,
+ if (session->itrace_synth_opts)
+ itrace_synth_opts__set_default(&pt->synth_opts,
session->itrace_synth_opts->default_no_sample);
if (use_browser != -1) {
pt->synth_opts.branches = false;
--
2.9.5