[PATCH v2] media: rcar-csi2: Add checking to rcsi2_start_receiver()

[Nadezda Lutovinova]

If rcsi2_code_to_fmt() return NULL, then null pointer dereference occurs 
in the next cycle. That should not be possible now but adding checking 
protects from future bugs.
The patch adds checking if format is NULL.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Nadezda Lutovinova <lutovinova@xxxxxxxxx>
---
v2: fix subject and commit message, remove dev_err()
---
 drivers/media/platform/rcar-vin/rcar-csi2.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
index e28eff039688..d28f83f7698b 100644
--- a/drivers/media/platform/rcar-vin/rcar-csi2.c
+++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
@@ -553,6 +553,8 @@ static int rcsi2_start_receiver(struct rcar_csi2 *priv)
 
 	/* Code is validated in set_fmt. */
 	format = rcsi2_code_to_fmt(priv->mf.code);
+	if (!format)
+		return -EINVAL;
 
 	/*
 	 * Enable all supported CSI-2 channels with virtual channel and
-- 
2.17.1