[tip: perf/core] tools lib traceevent: Do not free tep->cmdlines in add_new_comm() on failure

From: tip-bot2 for Steven Rostedt (VMware)
Date: Thu Aug 29 2019 - 15:02:40 EST

The following commit has been merged into the perf/core branch of tip:

Commit-ID: b0215e2d6a18d8331b2d4a8b38ccf3eff783edb1
Gitweb: https://git.kernel.org/tip/b0215e2d6a18d8331b2d4a8b38ccf3eff783edb1
Author: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
AuthorDate: Wed, 28 Aug 2019 15:05:28 -04:00
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitterDate: Thu, 29 Aug 2019 08:36:12 -03:00

tools lib traceevent: Do not free tep->cmdlines in add_new_comm() on failure

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.

Fixes: a6d2a61ac653a ("tools lib traceevent: Remove some die() calls")
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: linux-trace-devel@xxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20190828191819.970121417@xxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
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 b36b536..13fd9fd 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,

qsort(cmdlines, tep->cmdline_count, sizeof(*cmdlines), cmdline_cmp);
- tep->cmdlines = cmdlines;

return 0;