Re: [syzbot] WARNING: lock held when returning to user space in ethnl_act_cable_test

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Subject: WARNING: lock held when returning to user space in ethnl_act_cable_test
Author: djahchankoike@xxxxxxxxx

#syz test

Fix an unreleased lock when taking the out_dev_put path.

Signed-off-by: Diogo Jahchan Koike <djahchankoike@xxxxxxxxx>
---
I'm not entirely sure why are there two labels
when all paths should release the lock, maybe
remove out_dev_put and out_rtnl for a simpler
out? I've kept it just in case, but I can make
the change if needed.
---
 net/ethtool/cabletest.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/ethtool/cabletest.c b/net/ethtool/cabletest.c
index 01db8f394869..c6ca1107c470 100644
--- a/net/ethtool/cabletest.c
+++ b/net/ethtool/cabletest.c
@@ -77,6 +77,7 @@ int ethnl_act_cable_test(struct sk_buff *skb, struct genl_info *info)
 				      info->extack);
 	if (IS_ERR_OR_NULL(phydev)) {
 		ret = -EOPNOTSUPP;
+		rtnl_unlock();
 		goto out_dev_put;
 	}
 
-- 
2.43.0