From: Xin Long lucien.xin@gmail.com
commit 9b6c08878e23adb7cc84bdca94d8a944b03f099e upstream.
Now when sctp_connect() is called with a wrong sa_family, it binds to a port but doesn't set bp->port, then sctp_get_af_specific will return NULL and sctp_connect() returns -EINVAL.
Then if sctp_bind() is called to bind to another port, the last port it has bound will leak due to bp->port is NULL by then.
sctp_connect() doesn't need to bind ports, as later __sctp_connect will do it if bp->port is NULL. So remove it from sctp_connect(). While at it, remove the unnecessary sockaddr.sa_family len check as it's already done in sctp_inet_connect.
Fixes: 644fbdeacf1d ("sctp: fix the issue that flags are ignored when using kernel_connect") Reported-by: syzbot+079bf326b38072f849d9@syzkaller.appspotmail.com Signed-off-by: Xin Long lucien.xin@gmail.com Acked-by: Marcelo Ricardo Leitner marcelo.leitner@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/sctp/socket.c | 21 ++------------------- 1 file changed, 2 insertions(+), 19 deletions(-)
--- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -3897,34 +3897,17 @@ out_nounlock: static int sctp_connect(struct sock *sk, struct sockaddr *addr, int addr_len, int flags) { - struct inet_sock *inet = inet_sk(sk); struct sctp_af *af; - int err = 0; + int err = -EINVAL;
lock_sock(sk); - pr_debug("%s: sk:%p, sockaddr:%p, addr_len:%d\n", __func__, sk, addr, addr_len);
- /* We may need to bind the socket. */ - if (!inet->inet_num) { - if (sk->sk_prot->get_port(sk, 0)) { - release_sock(sk); - return -EAGAIN; - } - inet->inet_sport = htons(inet->inet_num); - } - /* Validate addr_len before calling common connect/connectx routine. */ af = sctp_get_af_specific(addr->sa_family); - if (!af || addr_len < af->sockaddr_len) { - err = -EINVAL; - } else { - /* Pass correct addr len to common routine (so it knows there - * is only one address being passed. - */ + if (af && addr_len >= af->sockaddr_len) err = __sctp_connect(sk, addr, af->sockaddr_len, flags, NULL); - }
release_sock(sk); return err;