drm/mipi-dsi: Avoid potential NULL pointer dereference
The mipi_dsi_packet_create() function dereferences the msg pointer
before checking that it's valid. Move the dereference down to where it
is required to avoid potentially dereferencing a NULL pointer.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
index c0644bb..2d5ca8ee 100644
--- a/drivers/gpu/drm/drm_mipi_dsi.c
+++ b/drivers/gpu/drm/drm_mipi_dsi.c
@@ -323,8 +323,6 @@
int mipi_dsi_create_packet(struct mipi_dsi_packet *packet,
const struct mipi_dsi_msg *msg)
{
- const u8 *tx = msg->tx_buf;
-
if (!packet || !msg)
return -EINVAL;
@@ -353,8 +351,10 @@
packet->header[2] = (msg->tx_len >> 8) & 0xff;
packet->payload_length = msg->tx_len;
- packet->payload = tx;
+ packet->payload = msg->tx_buf;
} else {
+ const u8 *tx = msg->tx_buf;
+
packet->header[1] = (msg->tx_len > 0) ? tx[0] : 0;
packet->header[2] = (msg->tx_len > 1) ? tx[1] : 0;
}