[PATCH v3 net-next 2/8] sctp: Don't copy sk_sndbuf and sk_rcvbuf in sctp_sock_migrate().

sctp_sock_migrate() is called from 2 places.

1) sctp_accept() calls sp->pf->create_accept_sk() before
   sctp_sock_migrate(), and sp->pf->create_accept_sk() calls
   sctp_copy_sock().

2) sctp_do_peeloff() also calls sctp_copy_sock() before
   sctp_sock_migrate().

sctp_copy_sock() copies sk_sndbuf and sk_rcvbuf from the
parent socket.

Let's not copy the two fields in sctp_sock_migrate().

Signed-off-by: Kuniyuki Iwashima <[email protected]>
---
 net/sctp/socket.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index d190e75e4645..735b1222af95 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -9523,12 +9523,9 @@ static int sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
 	struct sctp_bind_hashbucket *head;
 	int err;
 
-	/* Migrate socket buffer sizes and all the socket level options to the
-	 * new socket.
+	/* Migrate all the socket level options to the new socket.
+	 * Brute force copy old sctp opt.
 	 */
-	newsk->sk_sndbuf = oldsk->sk_sndbuf;
-	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
-	/* Brute force copy old sctp opt. */
 	sctp_copy_descendant(newsk, oldsk);
 
 	/* Restore the ep value that was overwritten with the above structure
-- 
2.51.1.851.g4ebd6896fd-goog