[PATCH 3.4 70/91] ASoC: core: fix possible ZERO_SIZE_PTR pointer dereferencing error.

[lizf]

From: Xiubo Li <Li.Xiubo@xxxxxxxxxxxxx>

3.4.105-rc1 review patch.  If anyone has any objections, please let me know.

------------------


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@xxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li <lizefan@xxxxxxxxxx>
---
 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 c88d974..34c1fbb 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -2799,7 +2799,7 @@ 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;
 
 	data = ucontrol->value.bytes.data;
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/