[media] media: Properly handle link flags in link setup, link notify callback

The link flags were not properly handled in __media_entity_setup_link
which could lead to link_notify callback to be called when the flags are
not modified. Fix this.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
index 23640ed44d85..056138f63c7d 100644
--- a/drivers/media/media-entity.c
+++ b/drivers/media/media-entity.c
@@ -378,7 +378,6 @@ EXPORT_SYMBOL_GPL(media_entity_create_link);
 
 static int __media_entity_setup_link_notify(struct media_link *link, u32 flags)
 {
-        const u32 mask = MEDIA_LNK_FL_ENABLED;
         int ret;
 
         /* Notify both entities. */
@@ -395,7 +394,7 @@ static int __media_entity_setup_link_notify(struct media_link *link, u32 flags)
                 return ret;
         }
 
-        link->flags = (link->flags & ~mask) | (flags & mask);
+        link->flags = flags;
         link->reverse->flags = link->flags;
 
         return 0;
@@ -417,6 +416,7 @@ static int __media_entity_setup_link_notify(struct media_link *link, u32 flags)
  */
 int __media_entity_setup_link(struct media_link *link, u32 flags)
 {
+        const u32 mask = MEDIA_LNK_FL_ENABLED;
         struct media_device *mdev;
         struct media_entity *source, *sink;
         int ret = -EBUSY;
@@ -424,6 +424,10 @@ int __media_entity_setup_link(struct media_link *link, u32 flags)
         if (link == NULL)
                 return -EINVAL;
 
+        /* The non-modifiable link flags must not be modified. */
+        if ((link->flags & ~mask) != (flags & ~mask))
+                return -EINVAL;
+
         if (link->flags & MEDIA_LNK_FL_IMMUTABLE)
                 return link->flags == flags ? 0 : -EINVAL;