[PATCH] veth: fix memory leak in veth_newlink()

[Rustam Kovhaev]

when register_netdevice(dev) fails we should check whether struct
veth_rq has been allocated via ndo_init callback and free it, because,
depending on the code path, register_netdevice() might not call
priv_destructor() callback

Reported-and-tested-by: syzbot+59ef240dd8f0ed7598a8@xxxxxxxxxxxxxxxxxxxxxxxxx
Link: https://syzkaller.appspot.com/bug?extid=59ef240dd8f0ed7598a8
Signed-off-by: Rustam Kovhaev <rkovhaev@xxxxxxxxx>
---
 drivers/net/veth.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index a475f48d43c4..e40ca62a046a 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1394,7 +1394,9 @@ static int veth_newlink(struct net *src_net, struct net_device *dev,
 	return 0;
 
 err_register_dev:
-	/* nothing to do */
+	priv = netdev_priv(dev);
+	if (priv->rq)
+		veth_dev_free(dev);
 err_configure_peer:
 	unregister_netdevice(peer);
 	return err;
-- 
2.28.0