[PATCH 1/2] tracing: Fix memory leak in create_filter()

Steven Rostedt
2018-12-10T20:42:47Z

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

The create_filter() calls create_filter_start() which allocates a
"parse_error" descriptor, but fails to call create_filter_finish() that
frees it.

The op_stack and inverts in predicate_parse() were also not freed.

Found by kmemleak detector.

Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: stable@vger.kernel.org
Fixes: 80765597bc587 ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace_events_filter.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 84a65173b1e9..5574e862de8d 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -570,11 +570,13 @@ predicate_parse(const char *str, int nr_parens, int nr_preds,
}
}

+ kfree(op_stack);
+ kfree(inverts);
return prog;
out_free:
kfree(op_stack);
- kfree(prog_stack);
kfree(inverts);
+ kfree(prog_stack);
return ERR_PTR(ret);
}

@@ -1718,6 +1720,7 @@ static int create_filter(struct trace_event_call *call,
err = process_preds(call, filter_string, *filterp, pe);
if (err && set_str)
append_filter_err(pe, *filterp);
+ create_filter_finish(pe);

return err;
}
--
2.19.1