[PATCH] ASoC: pxa: fix null-pointer dereference in filter()

[Zeng Heng]

kasprintf() would return NULL pointer when kmalloc() fail to allocate.
Need to check the return pointer before calling strcmp().

Fixes: 7a824e214e25 ("ASoC: mmp: add audio dma support")
Signed-off-by: Zeng Heng <zengheng4 at huawei.com>
---
 sound/soc/pxa/mmp-pcm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/pxa/mmp-pcm.c b/sound/soc/pxa/mmp-pcm.c
index 5d520e18e512..99b245e3079a 100644
--- a/sound/soc/pxa/mmp-pcm.c
+++ b/sound/soc/pxa/mmp-pcm.c
@@ -98,7 +98,7 @@ static bool filter(struct dma_chan *chan, void *param)
 
 	devname = kasprintf(GFP_KERNEL, "%s.%d", dma_data->dma_res->name,
 		dma_data->ssp_id);
-	if ((strcmp(dev_name(chan->device->dev), devname) == 0) &&
+	if (devname && (strcmp(dev_name(chan->device->dev), devname) == 0) &&
 		(chan->chan_id == dma_data->dma_res->start)) {
 		found = true;
 	}
-- 
2.25.1