From: Steven Rostedt <rostedt@xxxxxxxxxxx> At the end of process_filter(), collapse_tree() was changed to update the parg parameter, but the reassignment after the call wasn't removed. What happens is that the "current_op" gets modified and freed and parg is assigned to the new allocated argument. But after the call to collapse_tree(), parg is assigned again to the just freed "current_op", and this causes the tool to crash. The current_op variable must also be assigned to NULL in case of error, otherwise it will cause it to be free()ed twice. Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx # 3.14+ Fixes: 42d6194d133c ("tools lib traceevent: Refactor process_filter()") Link: http://lkml.kernel.org/r/20160511150936.678c18a1@xxxxxxxxxxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/lib/traceevent/parse-filter.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/lib/traceevent/parse-filter.c b/tools/lib/traceevent/parse-filter.c index 0144b3d1bb77..88cccea3ca99 100644 --- a/tools/lib/traceevent/parse-filter.c +++ b/tools/lib/traceevent/parse-filter.c @@ -1164,11 +1164,11 @@ process_filter(struct event_format *event, struct filter_arg **parg, current_op = current_exp; ret = collapse_tree(current_op, parg, error_str); + /* collapse_tree() may free current_op, and updates parg accordingly */ + current_op = NULL; if (ret < 0) goto fail; - *parg = current_op; - free(token); return 0; -- 2.5.5 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html