From: Xin Long Date: Sun, 13 Nov 2016 13:44:37 +0000 (+0800) Subject: sctp: change sk state only when it has assocs in sctp_shutdown X-Git-Tag: v5.15~12473^2~2 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=5bf35ddfee052d44f39ebaa395d87101c8918405;p=mirror_ubuntu-kernels.git sctp: change sk state only when it has assocs in sctp_shutdown Now when users shutdown a sock with SEND_SHUTDOWN in sctp, even if this sock has no connection (assoc), sk state would be changed to SCTP_SS_CLOSING, which is not as we expect. Besides, after that if users try to listen on this sock, kernel could even panic when it dereference sctp_sk(sk)->bind_hash in sctp_inet_listen, as bind_hash is null when sock has no assoc. This patch is to move sk state change after checking sk assocs is not empty, and also merge these two if() conditions and reduce indent level. Fixes: d46e416c11c8 ("sctp: sctp should change socket state when shutdown is received") Reported-by: Andrey Konovalov Tested-by: Andrey Konovalov Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller --- diff --git a/net/sctp/socket.c b/net/sctp/socket.c index faa48ff5cf4b..f23ad913dc7a 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -4285,19 +4285,18 @@ static void sctp_shutdown(struct sock *sk, int how) { struct net *net = sock_net(sk); struct sctp_endpoint *ep; - struct sctp_association *asoc; if (!sctp_style(sk, TCP)) return; - if (how & SEND_SHUTDOWN) { + ep = sctp_sk(sk)->ep; + if (how & SEND_SHUTDOWN && !list_empty(&ep->asocs)) { + struct sctp_association *asoc; + sk->sk_state = SCTP_SS_CLOSING; - ep = sctp_sk(sk)->ep; - if (!list_empty(&ep->asocs)) { - asoc = list_entry(ep->asocs.next, - struct sctp_association, asocs); - sctp_primitive_SHUTDOWN(net, asoc, NULL); - } + asoc = list_entry(ep->asocs.next, + struct sctp_association, asocs); + sctp_primitive_SHUTDOWN(net, asoc, NULL); } }