drivers/media/platform/rockchip/rkcif/rkcif-interface.c | 3 ++- drivers/media/platform/rockchip/rkcif/rkcif-stream.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-)
The pads missed checks for connected devices which may a null dereference
when the stream is enabled.
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000020
pc : rkcif_interface_enable_streams+0x48/0xf0
lr : rkcif_interface_enable_streams+0x44/0xf0
Call trace:
rkcif_interface_enable_streams+0x48/0xf0
v4l2_subdev_enable_streams+0x26c/0x3f0
rkcif_stream_start_streaming+0x140/0x278
vb2_start_streaming+0x74/0x188
vb2_core_streamon+0xe0/0x1d8
vb2_ioctl_streamon+0x60/0xa8
v4l_streamon+0x2c/0x40
__video_do_ioctl+0x34c/0x400
video_usercopy+0x2d0/0x800
video_ioctl2+0x20/0x60
v4l2_ioctl+0x48/0x78
Fixes: 501802e2ad51 ("media: rockchip: rkcif: add abstraction for dma blocks")
Fixes: 85411d17bee9 ("media: rockchip: rkcif: add abstraction for interface and crop blocks")
Signed-off-by: Dang Huynh <dang.huynh@mainlining.org>
---
The RKCIF driver missed MEDIA_PAD_FL_MUST_CONNECT, which causes a null
dereference when the stream starts if the links are misconfigured.
---
drivers/media/platform/rockchip/rkcif/rkcif-interface.c | 3 ++-
drivers/media/platform/rockchip/rkcif/rkcif-stream.c | 2 +-
2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/media/platform/rockchip/rkcif/rkcif-interface.c b/drivers/media/platform/rockchip/rkcif/rkcif-interface.c
index 523103872b7a..414a9980cf2e 100644
--- a/drivers/media/platform/rockchip/rkcif/rkcif-interface.c
+++ b/drivers/media/platform/rockchip/rkcif/rkcif-interface.c
@@ -378,7 +378,8 @@ int rkcif_interface_register(struct rkcif_device *rkcif,
snprintf(sd->name, sizeof(sd->name), "rkcif-mipi%d",
interface->index - RKCIF_MIPI_BASE);
- pads[RKCIF_IF_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
+ pads[RKCIF_IF_PAD_SINK].flags = MEDIA_PAD_FL_SINK |
+ MEDIA_PAD_FL_MUST_CONNECT;
pads[RKCIF_IF_PAD_SRC].flags = MEDIA_PAD_FL_SOURCE;
ret = media_entity_pads_init(&sd->entity, RKCIF_IF_PAD_MAX, pads);
if (ret)
diff --git a/drivers/media/platform/rockchip/rkcif/rkcif-stream.c b/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
index e00010a91e8b..201542b55f00 100644
--- a/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
+++ b/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
@@ -555,7 +555,7 @@ int rkcif_stream_register(struct rkcif_device *rkcif,
vdev->vfl_dir = VFL_DIR_RX;
video_set_drvdata(vdev, stream);
- stream->pad.flags = MEDIA_PAD_FL_SINK;
+ stream->pad.flags = MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_MUST_CONNECT;
stream->pix.height = CIF_MIN_HEIGHT;
stream->pix.width = CIF_MIN_WIDTH;
---
base-commit: 3f24e4edcd1b8981c6b448ea2680726dedd87279
change-id: 20260129-rkcif-null-fbc0be41f81a
Best regards,
--
Dang Huynh <dang.huynh@mainlining.org>On Thu, Jan 29, 2026 at 02:24:02PM +0700, Dang Huynh wrote:
> The pads missed checks for connected devices which may a null dereference
> when the stream is enabled.
>
> Unable to handle kernel NULL pointer dereference at virtual address
> 0000000000000020
> pc : rkcif_interface_enable_streams+0x48/0xf0
> lr : rkcif_interface_enable_streams+0x44/0xf0
> Call trace:
> rkcif_interface_enable_streams+0x48/0xf0
> v4l2_subdev_enable_streams+0x26c/0x3f0
> rkcif_stream_start_streaming+0x140/0x278
> vb2_start_streaming+0x74/0x188
> vb2_core_streamon+0xe0/0x1d8
> vb2_ioctl_streamon+0x60/0xa8
> v4l_streamon+0x2c/0x40
> __video_do_ioctl+0x34c/0x400
> video_usercopy+0x2d0/0x800
> video_ioctl2+0x20/0x60
> v4l2_ioctl+0x48/0x78
>
> Fixes: 501802e2ad51 ("media: rockchip: rkcif: add abstraction for dma blocks")
> Fixes: 85411d17bee9 ("media: rockchip: rkcif: add abstraction for interface and crop blocks")
> Signed-off-by: Dang Huynh <dang.huynh@mainlining.org>
> ---
> The RKCIF driver missed MEDIA_PAD_FL_MUST_CONNECT, which causes a null
> dereference when the stream starts if the links are misconfigured.
The change looks fine,
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
I'd like a review from Michael though.
> ---
> drivers/media/platform/rockchip/rkcif/rkcif-interface.c | 3 ++-
> drivers/media/platform/rockchip/rkcif/rkcif-stream.c | 2 +-
> 2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/platform/rockchip/rkcif/rkcif-interface.c b/drivers/media/platform/rockchip/rkcif/rkcif-interface.c
> index 523103872b7a..414a9980cf2e 100644
> --- a/drivers/media/platform/rockchip/rkcif/rkcif-interface.c
> +++ b/drivers/media/platform/rockchip/rkcif/rkcif-interface.c
> @@ -378,7 +378,8 @@ int rkcif_interface_register(struct rkcif_device *rkcif,
> snprintf(sd->name, sizeof(sd->name), "rkcif-mipi%d",
> interface->index - RKCIF_MIPI_BASE);
>
> - pads[RKCIF_IF_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> + pads[RKCIF_IF_PAD_SINK].flags = MEDIA_PAD_FL_SINK |
> + MEDIA_PAD_FL_MUST_CONNECT;
> pads[RKCIF_IF_PAD_SRC].flags = MEDIA_PAD_FL_SOURCE;
> ret = media_entity_pads_init(&sd->entity, RKCIF_IF_PAD_MAX, pads);
> if (ret)
> diff --git a/drivers/media/platform/rockchip/rkcif/rkcif-stream.c b/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
> index e00010a91e8b..201542b55f00 100644
> --- a/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
> +++ b/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
> @@ -555,7 +555,7 @@ int rkcif_stream_register(struct rkcif_device *rkcif,
> vdev->vfl_dir = VFL_DIR_RX;
> video_set_drvdata(vdev, stream);
>
> - stream->pad.flags = MEDIA_PAD_FL_SINK;
> + stream->pad.flags = MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_MUST_CONNECT;
>
> stream->pix.height = CIF_MIN_HEIGHT;
> stream->pix.width = CIF_MIN_WIDTH;
>
> ---
> base-commit: 3f24e4edcd1b8981c6b448ea2680726dedd87279
> change-id: 20260129-rkcif-null-fbc0be41f81a
--
Regards,
Laurent Pinchart
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