From 1d481458816d9424c8a05833ce0ebe72194a350e Mon Sep 17 00:00:00 2001 From: Leo Yan Date: Mon, 8 Jul 2019 22:39:35 +0800 Subject: [PATCH] perf intel-bts: 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/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 Acked-by: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jiri Olsa Cc: Mathieu Poirier Cc: Namhyung Kim Cc: Suzuki Poulouse Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20190708143937.7722-3-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo --- 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 5a21bcdb8ef7..5560e95afdda 100644 --- a/tools/perf/util/intel-bts.c +++ b/tools/perf/util/intel-bts.c @@ -891,13 +891,12 @@ 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; }