Em Mon, Jul 08, 2019 at 10:39:36PM +0800, Leo Yan escreveu:
> Based on the following report from Smatch, fix the potential
> NULL pointer dereference check.
Adrian, are you ok now with these two for pt and bts? Can I have your
acked-by?
- Arnaldo
> tools/perf/util/intel-pt.c:3200
> intel_pt_process_auxtrace_info() error: we previously assumed
> 'session->itrace_synth_opts' could be null (see line 3196)
>
> tools/perf/util/intel-pt.c:3206
> intel_pt_process_auxtrace_info() warn: variable dereferenced before
> check 'session->itrace_synth_opts' (see line 3200)
>
> tools/perf/util/intel-pt.c
> 3196 if (session->itrace_synth_opts &&
> session->itrace_synth_opts->set) {
> 3197 pt->synth_opts = *session->itrace_synth_opts;
> 3198 } else {
> 3199 itrace_synth_opts__set_default(&pt->synth_opts,
> 3200
> session->itrace_synth_opts->default_no_sample);
> ^^^^^^^^^^^^^^^^^^^^^^^^^^
> 3201 if (!session->itrace_synth_opts->default_no_sample &&
> 3202 !session->itrace_synth_opts->inject) {
> 3203 pt->synth_opts.branches = false;
> 3204 pt->synth_opts.callchain = true;
> 3205 }
> 3206 if (session->itrace_synth_opts)
> ^^^^^^^^^^^^^^^^^^^^^^^^^^
> 3207 pt->synth_opts.thread_stack =
> 3208 session->itrace_synth_opts->thread_stack;
> 3209 }
>
> 'session->itrace_synth_opts' is impossible to be a NULL pointer in
> intel_pt_process_auxtrace_info(), thus this patch removes the NULL
> test for 'session->itrace_synth_opts'.
>
> Signed-off-by: Leo Yan <leo....@linaro.org>
> ---
> tools/perf/util/intel-pt.c | 13 +++++--------
> 1 file changed, 5 insertions(+), 8 deletions(-)
>
> diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
> index c76a96f777fb..df061599fef4 100644
> --- a/tools/perf/util/intel-pt.c
> +++ b/tools/perf/util/intel-pt.c
> @@ -3210,7 +3210,7 @@ int intel_pt_process_auxtrace_info(union perf_event
> *event,
> goto err_delete_thread;
> }
>
> - if (session->itrace_synth_opts && session->itrace_synth_opts->set) {
> + if (session->itrace_synth_opts->set) {
> pt->synth_opts = *session->itrace_synth_opts;
> } else {
> itrace_synth_opts__set_default(&pt->synth_opts,
> @@ -3220,8 +3220,7 @@ int intel_pt_process_auxtrace_info(union perf_event
> *event,
> pt->synth_opts.branches = false;
> pt->synth_opts.callchain = true;
> }
> - if (session->itrace_synth_opts)
> - pt->synth_opts.thread_stack =
> + pt->synth_opts.thread_stack =
> session->itrace_synth_opts->thread_stack;
> }
>
> @@ -3241,11 +3240,9 @@ int intel_pt_process_auxtrace_info(union perf_event
> *event,
> pt->cbr2khz = tsc_freq / pt->max_non_turbo_ratio / 1000;
> }
>
> - if (session->itrace_synth_opts) {
> - err = intel_pt_setup_time_ranges(pt,
> session->itrace_synth_opts);
> - if (err)
> - goto err_delete_thread;
> - }
> + err = intel_pt_setup_time_ranges(pt, session->itrace_synth_opts);
> + if (err)
> + goto err_delete_thread;
>
> if (pt->synth_opts.calls)
> pt->branches_filter |= PERF_IP_FLAG_CALL | PERF_IP_FLAG_ASYNC |
> --
> 2.17.1
--
- Arnaldo
