[tip:perf/core] tools lib traceevent: Make sure that arg->op. right is set properly

[tip-bot for Namhyung Kim <namhyung.kim@lge.com>]

Commit-ID:  41e51a289b3ca83e08395213f4488c9c7c6b2e29
Gitweb:     http://git.kernel.org/tip/41e51a289b3ca83e08395213f4488c9c7c6b2e29
Author:     Namhyung Kim <namhyung.kim@lge.com>
AuthorDate: Wed, 19 Sep 2012 15:58:42 +0900
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Mon, 24 Sep 2012 12:01:21 -0300

tools lib traceevent: Make sure that arg->op.right is set properly

When process_op failed, @arg will be freed on a caller with type of
PRINT_OP.  Thus free_arg() will try to free ->op.right field which can
have stale value if something bad happens in the middle.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1348037924-17568-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/traceevent/event-parse.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index 6270ee2..27088c5 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -1719,6 +1719,7 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		arg->op.left = left;
 		arg->op.prio = 0;
 
+		/* it will set arg->op.right */
 		type = process_cond(event, arg, tok);
 
 	} else if (strcmp(token, ">>") == 0 ||
@@ -1745,6 +1746,7 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 		arg->type = PRINT_OP;
 		arg->op.op = token;
 		arg->op.left = left;
+		arg->op.right = NULL;
 
 		if (set_op_prio(arg) == -1) {
 			event->flags |= EVENT_FL_FAILED;
@@ -1792,6 +1794,7 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 
 		arg->op.prio = 0;
 
+		/* it will set arg->op.right */
 		type = process_array(event, arg, tok);
 
 	} else {