Hi Dafna,
Thanks for the patch. Just small comments below.
On 8/29/19 8:00 AM, Dafna Hirschfeld wrote:
> Userspace can disable links and create pipelines that
> do not start with a source entity. Trying to stream
> from such a pipeline should fail with -EPIPE
> currently this is not handled and cause kernel crash.
>
> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@xxxxxxxxxxxxx>
> ---
> Hi,
> These are the commands to reproduce the crash:
> media-ctl -d0 -l "5:1->21:0[0]" -v
> v4l2-ctl -z platform:vimc -d "RGB/YUV Capture" -v width=1920,height=1440
> v4l2-ctl --stream-mmap --stream-count=100 -d /dev/video2
>
> drivers/media/platform/vimc/vimc-streamer.c | 39 +++++++++++++++------
> 1 file changed, 28 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/media/platform/vimc/vimc-streamer.c b/drivers/media/platform/vimc/vimc-streamer.c
> index 048d770e498b..bfc7921c7a8b 100644
> --- a/drivers/media/platform/vimc/vimc-streamer.c
> +++ b/drivers/media/platform/vimc/vimc-streamer.c
> @@ -13,6 +13,19 @@
>
> #include "vimc-streamer.h"
>
> +/**
> + * Check if the entity has only source pads
> + */
please add docs like the other functions in this file.
> +static bool vimc_is_source(struct media_entity *ent)
> +{
> + int i;
unsigned
Regards,
Helen
> +
> + for (i = 0; i < ent->num_pads; i++)
> + if (ent->pads[i].flags & MEDIA_PAD_FL_SINK)
> + return false;
> + return true;
> +}
> +
> /**
> * vimc_get_source_entity - get the entity connected with the first sink pad
> *
> @@ -83,14 +96,12 @@ static int vimc_streamer_pipeline_init(struct vimc_stream *stream,
> struct media_entity *entity;
> struct video_device *vdev;
> struct v4l2_subdev *sd;
> - int ret = 0;
> + int ret = -EINVAL;
>
> stream->pipe_size = 0;
> while (stream->pipe_size < VIMC_STREAMER_PIPELINE_MAX_SIZE) {
> - if (!ved) {
> - vimc_streamer_pipeline_terminate(stream);
> - return -EINVAL;
> - }
> + if (!ved)
> + break;
> stream->ved_pipeline[stream->pipe_size++] = ved;
>
> if (is_media_entity_v4l2_subdev(ved->ent)) {
> @@ -99,15 +110,22 @@ static int vimc_streamer_pipeline_init(struct vimc_stream *stream,
> if (ret && ret != -ENOIOCTLCMD) {
> pr_err("subdev_call error %s\n",
> ved->ent->name);
> - vimc_streamer_pipeline_terminate(stream);
> - return ret;
> + break;
> }
> }
>
> entity = vimc_get_source_entity(ved->ent);
> - /* Check if the end of the pipeline was reached*/
> - if (!entity)
> + /* Check if the end of the pipeline was reached */
> + if (!entity) {
> + /* the first entity of the pipe should be source only */
> + if (!vimc_is_source(ved->ent)) {
> + pr_err("first entity in the pipe '%s' is not a source\n",
> + ved->ent->name);
> + ret = -EPIPE;
> + break;
> + }
> return 0;
> + }
>
> /* Get the next device in the pipeline */
> if (is_media_entity_v4l2_subdev(entity)) {
> @@ -120,9 +138,8 @@ static int vimc_streamer_pipeline_init(struct vimc_stream *stream,
> ved = video_get_drvdata(vdev);
> }
> }
> -
> vimc_streamer_pipeline_terminate(stream);
> - return -EINVAL;
> + return ret;
> }
>
> /**
>
