[PATCH 3.16 279/305] ALSA: timer: Fix leak in events via snd_timer_user_tinterrupt

Ben Hutchings
2016-08-14T18:00:51Z

From: Kangjie Lu <kangjielu@gmail.com>

commit e4ec8cc8039a7063e24204299b462bd1383184a5 upstream.

The stack object “r1” has a total size of 32 bytes. Its field
“event” and “val” both contain 4 bytes padding. These 8 bytes
padding bytes are sent to user without being initialized.

Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
sound/core/timer.c | 1 +
1 file changed, 1 insertion(+)

--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -1286,6 +1286,7 @@ static void snd_timer_user_tinterrupt(st
}
if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
tu->last_resolution != resolution) {
+ memset(&r1, 0, sizeof(r1));
r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
r1.tstamp = tstamp;
r1.val = resolution;