Re: [PATCH] drm/bridge: ti-sn65dsi83: Fix null pointer dereference in remove callback

From: Marek Vasut
Date: Thu Jun 17 2021 - 08:50:00 EST


On 6/17/21 1:19 PM, Jonathan Liu wrote:
If attach has not been called, unloading the driver can result in a null
pointer dereference in mipi_dsi_detach as ctx->dsi has not been assigned
yet.

Fixes: ceb515ba29ba6b ("drm/bridge: ti-sn65dsi83: Add TI SN65DSI83 and SN65DSI84 driver")
Signed-off-by: Jonathan Liu <net147@xxxxxxxxx>
---
drivers/gpu/drm/bridge/ti-sn65dsi83.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
index 750f2172ef08..8e9f45c5c7c1 100644
--- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c
+++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
@@ -671,8 +671,11 @@ static int sn65dsi83_remove(struct i2c_client *client)
{
struct sn65dsi83 *ctx = i2c_get_clientdata(client);
- mipi_dsi_detach(ctx->dsi);
- mipi_dsi_device_unregister(ctx->dsi);
+ if (ctx->dsi) {
+ mipi_dsi_detach(ctx->dsi);
+ mipi_dsi_device_unregister(ctx->dsi);
+ }
+
drm_bridge_remove(&ctx->bridge);
of_node_put(ctx->host_node);

Looks OK to me.

Reviewed-by: Marek Vasut <marex@xxxxxxx>

Thanks !