On 02/02/2025 23:56, Sabrina Dubroca wrote:
2025-01-13, 10:31:24 +0100, Antonio Quartulli wrote:+static int ovpn_peer_del_p2p(struct ovpn_peer *peer, + enum ovpn_del_peer_reason reason) +{ + struct ovpn_peer *tmp; + + lockdep_assert_held(&peer->ovpn->lock); + + tmp = rcu_dereference_protected(peer->ovpn->peer, + lockdep_is_held(&peer->ovpn->lock)); + if (tmp != peer) { + DEBUG_NET_WARN_ON_ONCE(1);I think this WARN should be removed. If 2 almost-simultanenous DEL_PEER manage to fetch the peer, the first will delete it and NULL peer->ovpn->peer, then when it releases ovpn->lock, the 2nd will find NULL != peer and hit this WARN. (probably not happening in practical cases, but syzbot will manage to hit it)
I can see this happening with two almost-simultaneous netlink PEER_DEL calls.
Thanks, will get rid of the warning. Regards,
+ return -ENOENT; + } + + ovpn_peer_remove(peer, reason); + + return 0; +}
-- Antonio Quartulli OpenVPN Inc.
