Re: [PATCH net] tcp/dccp: remove obsolete WARN_ON() in icmp handlers

From: Eric Dumazet <redacted>
Date: Wed, 16 Mar 2016 22:52:15 -0700

From: Eric Dumazet <edumazet@google.com>

Now SYN_RECV request sockets are installed in ehash table, an ICMP
handler can find a request socket while another cpu handles an incoming
packet transforming this SYN_RECV request socket into an ESTABLISHED
socket.

We need to remove the now obsolete WARN_ON(req->sk), since req->sk
is set when a new child is created and added into listener accept queue.

If this race happens, the ICMP will do nothing special.

Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Ben Lazarus <redacted>
Reported-by: Neal Cardwell <ncardwell@google.com>

Applied and queued up for -stable, thanks Eric.