[PATCH 1/2] tools lib traceevent: Do not free tep->cmdlines in add_new_comm() on failure

[Steven Rostedt <rostedt@goodmis.org>]

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

If the re-allocation of tep->cmdlines succeeds, then the previous allocation
of tep->cmdlines will be freed. If we later fail in add_new_comm(), we must
not free cmdlines, and also should assign tep->cmdlines to the new
allocation. Otherwise when freeing tep, the tep->cmdlines will be pointing
to garbage.

Cc: stable@vger.kernel.org
Fixes: a6d2a61ac653a ("tools lib traceevent: Remove some die() calls")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 tools/lib/traceevent/event-parse.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index b36b536a9fcb..13fd9fdf91e0 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -269,10 +269,10 @@ static int add_new_comm(struct tep_handle *tep,
 		errno = ENOMEM;
 		return -1;
 	}
+	tep->cmdlines = cmdlines;
 
 	cmdlines[tep->cmdline_count].comm = strdup(comm);
 	if (!cmdlines[tep->cmdline_count].comm) {
-		free(cmdlines);
 		errno = ENOMEM;
 		return -1;
 	}
@@ -283,7 +283,6 @@ static int add_new_comm(struct tep_handle *tep,
 		tep->cmdline_count++;
 
 	qsort(cmdlines, tep->cmdline_count, sizeof(*cmdlines), cmdline_cmp);
-	tep->cmdlines = cmdlines;
 
 	return 0;
 }
-- 
2.20.1