From: Gaurav Singh <gaurav1086@xxxxxxxxx> [ Upstream commit 11b6e5482e178055ec1f2444b55f2518713809d1 ] The 'evname' variable can be NULL, as it is checked a few lines back, check it before using. Fixes: 9e207ddfa207 ("perf report: Show call graph from reference events") Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Kan Liang <kan.liang@xxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lore.kernel.org/lkml/ Signed-off-by: Gaurav Singh <gaurav1086@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/perf/builtin-report.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index 429c3e140dc32..35a10b5985447 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -401,8 +401,7 @@ static size_t hists__fprintf_nr_sample_events(struct hists *hists, struct report if (evname != NULL) ret += fprintf(fp, " of event '%s'", evname); - if (symbol_conf.show_ref_callgraph && - strstr(evname, "call-graph=no")) { + if (symbol_conf.show_ref_callgraph && evname && strstr(evname, "call-graph=no")) { ret += fprintf(fp, ", show reference callgraph"); } -- 2.25.1