UPSTREAM: ALSA: timer: Fix leak in events via snd_timer_user_ccallback

(cherry pick from commit 9a47e9cff994f37f7f0dbd9ae23740d0f64f9fe6)

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>
Bug: 28980217
Change-Id: I2e4c27352894b9f1f4c808b8db3ae5f9284faec1

diff --git a/sound/core/timer.c b/sound/core/timer.c
index 185cb59b499771acc6465e2329ae5f90a5f56c8c..a3f547badd380d5c0f3ff6a2dac0c8d163a2ff3a 100644 (file)
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -1247,6 +1247,7 @@ static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
                tu->tstamp = *tstamp;
        if ((tu->filter & (1 << event)) == 0 || !tu->tread)
                return;
+       memset(&r1, 0, sizeof(r1));
        r1.event = event;
        r1.tstamp = *tstamp;
        r1.val = resolution;