media: mali-c55: Fix possible ERR_PTR in enable_streams

The media_pad_remote_pad_unique() function returns either a valid
pointer or an ERR_PTR() on failure (-ENOTUNIQ if multiple links are
enabled, -ENOLINK if no connected pad is found). The return value
was assigned directly to isp->remote_src and dereferenced in the
next line without checking for errors, which could lead to an
ERR_PTR dereference.

Add proper error checking with IS_ERR() before dereferencing the
pointer. Also set isp->remote_src to NULL on error to maintain
consistency with other error paths in the function.

Cc: stable@vger.kernel.org
Fixes: d5f281f3dd29 ("media: mali-c55: Add Mali-C55 ISP driver")
Signed-off-by: Alper Ak <alperyasinak1@gmail.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi+renesas@ideasonboard.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo.mondi+renesas@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>

diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-isp.c b/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
index dfa5dbe68c466a2e06e48ff456955002b92c7692..e128adf6ee37e480fa816af9fb1bc5d5f158e718 100644 (file)
--- a/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
@@ -333,6 +333,13 @@ static int mali_c55_isp_enable_streams(struct v4l2_subdev *sd,
 
        sink_pad = &isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO];
        isp->remote_src = media_pad_remote_pad_unique(sink_pad);
+       if (IS_ERR(isp->remote_src))  {
+               ret = PTR_ERR(isp->remote_src);
+               dev_err(mali_c55->dev, "Failed to get remote source pad: %d\n", ret);
+               isp->remote_src = NULL;
+               return ret;
+       }
+
        src_sd = media_entity_to_v4l2_subdev(isp->remote_src->entity);
 
        isp->frame_sequence = 0;