From: Xin Long <lucien.xin@gmail.com>
Date: Wed, 2 May 2018 13:39:46 +0800
Subject: sctp: use the old asoc when making the cookie-ack chunk in dupcook_d
Git-commit: 46e16d4b956867013e0bbd7f2bad206f4aa55752
Patch-mainline: v4.17-rc4
References: networking-stable-18_05_15

When processing a duplicate cookie-echo chunk, for case 'D', sctp will
not process the param from this chunk. It means old asoc has nothing
to be updated, and the new temp asoc doesn't have the complete info.

So there's no reason to use the new asoc when creating the cookie-ack
chunk. Otherwise, like when auth is enabled for cookie-ack, the chunk
can not be set with auth, and it will definitely be dropped by peer.

This issue is there since very beginning, and we fix it by using the
old asoc instead.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 net/sctp/sm_statefuns.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 98acfed45e3b..28c070e187c2 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -2056,7 +2056,7 @@ static enum sctp_disposition sctp_sf_do_dupcook_d(
 		}
 	}
 
-	repl = sctp_make_cookie_ack(new_asoc, chunk);
+	repl = sctp_make_cookie_ack(asoc, chunk);
 	if (!repl)
 		goto nomem;
 
-- 
2.18.0