From: Jesper Juhl <jj@chaosbits.net>
Date: Fri, 29 Oct 2010 18:40:23 +0000 (+0200)
Subject: ALSA: usb - driver neglects kmalloc return value check and may deref NULL
X-Git-Tag: upstream/snapshot3+hdmi~12401^2~27
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8a8d56b2a2f9aa423c3d8b6b1e2792c0492059ed;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git

ALSA: usb - driver neglects kmalloc return value check and may deref NULL

sound/usb/pcm.c::snd_usb_pcm_check_knot() fails to check the return value
from kmalloc() and may end up dereferencing a null pointer.
The patch below (compile tested only) should take care of that little
problem.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index cff3a3c..4132522 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -676,8 +676,10 @@ static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
 	if (!needs_knot)
 		return 0;
 
-	subs->rate_list.count = count;
 	subs->rate_list.list = kmalloc(sizeof(int) * count, GFP_KERNEL);
+	if (!subs->rate_list.list)
+		return -ENOMEM;
+	subs->rate_list.count = count;
 	subs->rate_list.mask = 0;
 	count = 0;
 	list_for_each_entry(fp, &subs->fmt_list, list) {