On Fri, May 18, 2018 at 11:44 AM, David Miller <da...@davemloft.net> wrote: > From: Eric Dumazet <eric.duma...@gmail.com> > Date: Fri, 18 May 2018 08:30:43 -0700 > >> We probably need to revert Willem patch >> (7ce875e5ecb8562fd44040f69bda96c999e38bbc) > > Is it really valid to reach ip_recv_err with an ipv6 socket?
I guess the issue is that setsockopt IPV6_ADDRFORM is not an atomic operation, so that the socket is neither fully ipv4 nor fully ipv6 by the time it reaches ip_recv_error. sk->sk_socket->ops = &inet_dgram_ops; < HERE > sk->sk_family = PF_INET; Even calling inet_recv_error to demux would not necessarily help. Safest would be to look up by skb->protocol, similar to what ipv6_recv_error does to handle v4-mapped-v6. Or to make that function safe with PF_INET and swap the order of the above two operations. All sound needlessly complicated for this rare socket option, but I don't have a better idea yet. Dropping on the floor is not nice, either.
