From 55f1ecb1199000932cf82e357841cc7498ac904f Mon Sep 17 00:00:00 2001 From: Sakari Ailus Date: Fri, 24 Feb 2023 16:00:46 +0100 Subject: [PATCH] media: v4l: subdev: Make link validation safer Link validation currently accesses invalid pointers if the link passed to it is not between two sub-devices. This is of course a driver bug. Ignore the error but print a warning message, as this is how it used to work previously. Fixes: a6b995ed03ff ("media: subdev: use streams in v4l2_subdev_link_validate()") Reported-by: Hans de Goede Signed-off-by: Sakari Ailus Tested-by: Hans de Goede Reviewed-by: Tomi Valkeinen Reviewed-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-subdev.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index 03dc5f68ffad..c7154a7f696a 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -1258,6 +1258,16 @@ int v4l2_subdev_link_validate(struct media_link *link) bool states_locked; int ret; + if (!is_media_entity_v4l2_subdev(link->sink->entity) || + !is_media_entity_v4l2_subdev(link->source->entity)) { + pr_warn_once("%s of link '%s':%u->'%s':%u is not a V4L2 sub-device, driver bug!\n", + !is_media_entity_v4l2_subdev(link->sink->entity) ? + "sink" : "source", + link->source->entity->name, link->source->index, + link->sink->entity->name, link->sink->index); + return 0; + } + sink_sd = media_entity_to_v4l2_subdev(link->sink->entity); source_sd = media_entity_to_v4l2_subdev(link->source->entity);