Song Liu reported crash in perf record: > #0 0x0000000000500055 in ordered_events(float, long double,...)(...) () > #1 0x0000000000500196 in ordered_events.reinit () > #2 0x00000000004fe413 in perf_session.process_events () > #3 0x0000000000440431 in cmd_record () > #4 0x00000000004a439f in run_builtin () > #5 0x000000000042b3e5 in main ()"
This can happen when we get out of the buffers during event processing. The subsequent ordered_events__free assumes the oe->buffer != NULL and crashes. Adding the check to prevent that. Cc: Stephane Eranian <[email protected]> Fixes: d5ceb62b3654 ("perf ordered_events: Add 'struct ordered_events_buffer' layer") Reported-by: Song Liu <[email protected]> Link: http://lkml.kernel.org/n/[email protected] Signed-off-by: Jiri Olsa <[email protected]> --- tools/perf/util/ordered-events.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/ordered-events.c b/tools/perf/util/ordered-events.c index 897589507d97..ea523d3b248f 100644 --- a/tools/perf/util/ordered-events.c +++ b/tools/perf/util/ordered-events.c @@ -391,8 +391,10 @@ void ordered_events__free(struct ordered_events *oe) * Current buffer might not have all the events allocated * yet, we need to free only allocated ones ... */ - list_del(&oe->buffer->list); - ordered_events_buffer__free(oe->buffer, oe->buffer_idx, oe); + if (oe->buffer) { + list_del(&oe->buffer->list); + ordered_events_buffer__free(oe->buffer, oe->buffer_idx, oe); + } /* ... and continue with the rest */ list_for_each_entry_safe(buffer, tmp, &oe->to_free, list) { -- 2.17.2
