[PATCH] drm/dsi: Do the 'msg' check prior to dereferencing it.

[PATCH] drm/dsi: Do the 'msg' check prior to dereferencing it.

[Fabio Estevam]

From: Fabio Estevam <fabio.estevam@freescale.com>

Commit a52879e8d7cb ("drm/dsi: Add message to packet translator") caused the
following Smatch complaint:

drivers/gpu/drm/drm_mipi_dsi.c:328 mipi_dsi_create_packet()
         warn: variable dereferenced before check 'msg' (see line 326)

Do the 'msg' check prior to dereferencing it.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com> 
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
 drivers/gpu/drm/drm_mipi_dsi.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
index c0644bb..a9812db 100644
--- a/drivers/gpu/drm/drm_mipi_dsi.c
+++ b/drivers/gpu/drm/drm_mipi_dsi.c
@@ -323,11 +323,13 @@ EXPORT_SYMBOL(mipi_dsi_packet_format_is_long);
 int mipi_dsi_create_packet(struct mipi_dsi_packet *packet,
 			   const struct mipi_dsi_msg *msg)
 {
-	const u8 *tx = msg->tx_buf;
+	const u8 *tx;
 
 	if (!packet || !msg)
 		return -EINVAL;
 
+	tx = msg->tx_buf;
+
 	/* do some minimum sanity checking */
 	if (!mipi_dsi_packet_format_is_short(msg->type) &&
 	    !mipi_dsi_packet_format_is_long(msg->type))
-- 
1.9.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH] drm/dsi: Do the 'msg' check prior to dereferencing it.

[Thierry Reding]

[-- Attachment #1.1: Type: text/plain, Size: 778 bytes --]

On Tue, Dec 16, 2014 at 10:04:34PM -0200, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam@freescale.com>
> 
> Commit a52879e8d7cb ("drm/dsi: Add message to packet translator") caused the
> following Smatch complaint:
> 
> drivers/gpu/drm/drm_mipi_dsi.c:328 mipi_dsi_create_packet()
>          warn: variable dereferenced before check 'msg' (see line 326)
> 
> Do the 'msg' check prior to dereferencing it.
> 
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> 
> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
> ---
>  drivers/gpu/drm/drm_mipi_dsi.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)

I've had an equivalent patch in the drm/panel tree for almost two weeks
but had forgotten to push. Pushed now.

Thierry

[-- Attachment #1.2: Type: application/pgp-signature, Size: 819 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/dri-devel