From: Jiri Olsa jolsa@kernel.org
[ Upstream commit 99d86c8b88393e29cf07c020585f2c8afbcdd97d ]
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 buffers during event processing.
The subsequent ordered_events__free() call assumes oe->buffer != NULL and crashes. Add a check to prevent that.
Reported-by: Song Liu liu.song.a23@gmail.com Signed-off-by: Jiri Olsa jolsa@kernel.org Reviewed-by: Song Liu liu.song.a23@gmail.com Tested-by: Song Liu liu.song.a23@gmail.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Stephane Eranian eranian@google.com Link: http://lkml.kernel.org/r/20190117113017.12977-1-jolsa@kernel.org Fixes: d5ceb62b3654 ("perf ordered_events: Add 'struct ordered_events_buffer' layer") Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 1904e7f6ec84d..77126a5fa9b69 100644 --- a/tools/perf/util/ordered-events.c +++ b/tools/perf/util/ordered-events.c @@ -359,8 +359,10 @@ 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) {