ASoC: simple-card: Add cpu_dai and codec_dai names NULL check

The name of cpu DAI maybe omitted, and then strlen() will lead
kernel panic.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c
index 7a9b6b4898c0..be7c1db5388f 100644
--- a/sound/soc/generic/simple-card.c
+++ b/sound/soc/generic/simple-card.c
@@ -142,6 +142,9 @@ static int asoc_simple_card_parse_of(struct device_node *node,
         if (ret < 0)
                 return ret;
 
+        if (!info->cpu_dai.name || !info->codec_dai.name)
+                return -EINVAL;
+
         /* card name is created from CPU/CODEC dai name */
         name = devm_kzalloc(dev,
                             strlen(info->cpu_dai.name)   +