From 8bedcbceaaa37f4362b8fb21e8c9d275e6cbe3a2 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 7 Oct 2020 10:49:28 +0300 Subject: [PATCH] ALSA: bebob: potential info leak in hwdep_read() commit b41c15f4e1c1f1657da15c482fa837c1b7384452 upstream. The "count" variable needs to be capped on every path so that we don't copy too much information to the user. Fixes: 618eabeae711 ("ALSA: bebob: Add hwdep interface") Signed-off-by: Dan Carpenter Acked-by: Takashi Sakamoto Cc: Link: https://lore.kernel.org/r/20201007074928.GA2529578@mwanda Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/firewire/bebob/bebob_hwdep.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/sound/firewire/bebob/bebob_hwdep.c b/sound/firewire/bebob/bebob_hwdep.c index 45b740f44c45..c362eb38ab90 100644 --- a/sound/firewire/bebob/bebob_hwdep.c +++ b/sound/firewire/bebob/bebob_hwdep.c @@ -36,12 +36,11 @@ hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count, } memset(&event, 0, sizeof(event)); + count = min_t(long, count, sizeof(event.lock_status)); if (bebob->dev_lock_changed) { event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS; event.lock_status.status = (bebob->dev_lock_count > 0); bebob->dev_lock_changed = false; - - count = min_t(long, count, sizeof(event.lock_status)); } spin_unlock_irq(&bebob->lock);