Patch "media: v4l2-core: Fix a potential resource leak in v4l2_fwnode_parse_link()" has been added to the 6.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    media: v4l2-core: Fix a potential resource leak in v4l2_fwnode_parse_link()

to the 6.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     media-v4l2-core-fix-a-potential-resource-leak-in-v4l.patch
and it can be found in the queue-6.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 827c96e7e73fd4a80821209839b9dd9b08deb389
Author: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Date:   Wed Jun 14 20:31:05 2023 +0200

    media: v4l2-core: Fix a potential resource leak in v4l2_fwnode_parse_link()
    
    [ Upstream commit d7b13edd4cb4bfa335b6008ab867ac28582d3e5c ]
    
    If fwnode_graph_get_remote_endpoint() fails, 'fwnode' is known to be NULL,
    so fwnode_handle_put() is a no-op.
    
    Release the reference taken from a previous fwnode_graph_get_port_parent()
    call instead.
    
    Also handle fwnode_graph_get_port_parent() failures.
    
    In order to fix these issues, add an error handling path to the function
    and the needed gotos.
    
    Fixes: ca50c197bd96 ("[media] v4l: fwnode: Support generic fwnode for parsing standardised properties")
    Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
    Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
    Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c
index 049c2f2001eaa..4fa9225aa3d93 100644
--- a/drivers/media/v4l2-core/v4l2-fwnode.c
+++ b/drivers/media/v4l2-core/v4l2-fwnode.c
@@ -568,19 +568,29 @@ int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode,
 	link->local_id = fwep.id;
 	link->local_port = fwep.port;
 	link->local_node = fwnode_graph_get_port_parent(fwnode);
+	if (!link->local_node)
+		return -ENOLINK;
 
 	fwnode = fwnode_graph_get_remote_endpoint(fwnode);
-	if (!fwnode) {
-		fwnode_handle_put(fwnode);
-		return -ENOLINK;
-	}
+	if (!fwnode)
+		goto err_put_local_node;
 
 	fwnode_graph_parse_endpoint(fwnode, &fwep);
 	link->remote_id = fwep.id;
 	link->remote_port = fwep.port;
 	link->remote_node = fwnode_graph_get_port_parent(fwnode);
+	if (!link->remote_node)
+		goto err_put_remote_endpoint;
 
 	return 0;
+
+err_put_remote_endpoint:
+	fwnode_handle_put(fwnode);
+
+err_put_local_node:
+	fwnode_handle_put(link->local_node);
+
+	return -ENOLINK;
 }
 EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link);