From: Ziyang Xuan william.xuanziyang@huawei.com
[ Upstream commit 03832a32bf8ff0a8305d94ddd3979835a807248f ]
When type is NFNL_CB_MUTEX and -EAGAIN error occur in nfnetlink_rcv_msg(), it does not execute nfnl_unlock(). That would trigger potential dead lock.
Fixes: 50f2db9e368f ("netfilter: nfnetlink: consolidate callback types") Signed-off-by: Ziyang Xuan william.xuanziyang@huawei.com Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Sasha Levin sashal@kernel.org --- net/netfilter/nfnetlink.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index 9c44518cb70f..6d18fb346868 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -294,6 +294,7 @@ static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, nfnl_lock(subsys_id); if (nfnl_dereference_protected(subsys_id) != ss || nfnetlink_find_client(type, ss) != nc) { + nfnl_unlock(subsys_id); err = -EAGAIN; break; }