Commit-ID: 99d86c8b88393e29cf07c020585f2c8afbcdd97d
Gitweb: https://git.kernel.org/tip/99d86c8b88393e29cf07c020585f2c8afbcdd97d
Author: Jiri Olsa <jolsa@xxxxxxxxxx>
AuthorDate: Thu, 17 Jan 2019 12:30:17 +0100
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Thu, 17 Jan 2019 11:07:00 -0300
perf ordered_events: Fix crash in ordered_events__free
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@xxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Reviewed-by: Song Liu <liu.song.a23@xxxxxxxxx>
Tested-by: Song Liu <liu.song.a23@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20190117113017.12977-1-jolsa@xxxxxxxxxx
Fixes: d5ceb62b3654 ("perf ordered_events: Add 'struct ordered_events_buffer' layer")
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
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) {
|