From: Leo Yan <leo.yan@xxxxxxxxxx> [ Upstream commit 1d481458816d9424c8a05833ce0ebe72194a350e ] Based on the following report from Smatch, fix the potential NULL pointer dereference check. tools/perf/util/intel-bts.c:898 intel_bts_process_auxtrace_info() error: we previously assumed 'session->itrace_synth_opts' could be null (see line 894) tools/perf/util/intel-bts.c:899 intel_bts_process_auxtrace_info() warn: variable dereferenced before check 'session->itrace_synth_opts' (see line 898) tools/perf/util/intel-bts.c 894 if (session->itrace_synth_opts && session->itrace_synth_opts->set) { 895 bts->synth_opts = *session->itrace_synth_opts; 896 } else { 897 itrace_synth_opts__set_default(&bts->synth_opts, 898 session->itrace_synth_opts->default_no_sample); ^^^^^^^^^^^^^^^^^^^^^^^^^^ 899 if (session->itrace_synth_opts) ^^^^^^^^^^^^^^^^^^^^^^^^^^ 900 bts->synth_opts.thread_stack = 901 session->itrace_synth_opts->thread_stack; 902 } 'session->itrace_synth_opts' is impossible to be a NULL pointer in intel_bts_process_auxtrace_info(), thus this patch removes the NULL test for 'session->itrace_synth_opts'. Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx> Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Suzuki Poulouse <suzuki.poulose@xxxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/20190708143937.7722-3-leo.yan@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/perf/util/intel-bts.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/intel-bts.c b/tools/perf/util/intel-bts.c index 47025bc727e1..7afcc462f9e7 100644 --- a/tools/perf/util/intel-bts.c +++ b/tools/perf/util/intel-bts.c @@ -900,13 +900,12 @@ int intel_bts_process_auxtrace_info(union perf_event *event, if (dump_trace) return 0; - if (session->itrace_synth_opts && session->itrace_synth_opts->set) { + if (session->itrace_synth_opts->set) { bts->synth_opts = *session->itrace_synth_opts; } else { itrace_synth_opts__set_default(&bts->synth_opts, session->itrace_synth_opts->default_no_sample); - if (session->itrace_synth_opts) - bts->synth_opts.thread_stack = + bts->synth_opts.thread_stack = session->itrace_synth_opts->thread_stack; } -- 2.20.1