parse-events: Handle failure of process op

If the process_op fails in event_read_print_args the failure
will go unnoticed.

Also do zero out the right arg on failed condition, since it
may point back to the original arg and cause a double free.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/parse-events.c b/parse-events.c
index 31ea61e..aa4ea94 100644
--- a/parse-events.c
+++ b/parse-events.c
@@ -1419,6 +1419,8 @@ process_cond(struct event_format *event, struct print_arg *top, char **tok)
         return type;
 
 out_free:
+        /* Top may point to itself */
+        top->op.right = NULL;
         free_token(token);
         free_arg(arg);
         return EVENT_ERROR;
@@ -2333,6 +2335,11 @@ static int event_read_print_args(struct event_format *event, struct print_arg **
                 if (type == EVENT_OP) {
                         type = process_op(event, arg, &token);
                         free_token(token);
+                        if (type == EVENT_ERROR) {
+                                *list = NULL;
+                                free_arg(arg);
+                                return -1;
+                        }
                         list = &arg->next;
                         continue;
                 }