[3.13.y.z extended stable] Patch "ASoC: core: fix possible ZERO_SIZE_PTR pointer dereferencing error." has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    ASoC: core: fix possible ZERO_SIZE_PTR pointer dereferencing error.

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.9.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 5d5a417836ee22110e5baf1f197b18a7cdc15383 Mon Sep 17 00:00:00 2001
From: Xiubo Li <Li.Xiubo at freescale.com>
Date: Sun, 28 Sep 2014 17:29:37 +0800
Subject: ASoC: core: fix possible ZERO_SIZE_PTR pointer dereferencing error.

commit 6596aa047b624aeec2ea321962cfdecf9953a383 upstream.

Since we cannot make sure the 'params->num_regs' will always be none
zero here, and then if it equals to zero, the kmemdup() will return
ZERO_SIZE_PTR, which equals to ((void *)16).

So this patch fix this with just doing the zero check before calling
kmemdup().

Signed-off-by: Xiubo Li <Li.Xiubo at freescale.com>
Signed-off-by: Mark Brown <broonie at kernel.org>
[ kamal: backport to 3.13-stable: context ]
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 sound/soc/soc-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index a66783e..a3830d1 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -3236,7 +3236,7 @@ int snd_soc_bytes_put(struct snd_kcontrol *kcontrol,
 	unsigned int val;
 	void *data;

-	if (!codec->using_regmap)
+	if (!codec->using_regmap || !params->num_regs)
 		return -EINVAL;

 	len = params->num_regs * codec->val_bytes;
--
1.9.1