sctp: not bind the socket in sctp_connect

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: 644fbdeacf ("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>
This commit is contained in:
Xin Long 2019-06-26 16:31:39 +08:00 committed by David S. Miller
parent 8ec3ede559
commit 9b6c08878e

View File

@ -4816,35 +4816,17 @@ 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 = addr_len < offsetofend(struct sockaddr, sa_family) ? NULL :
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.
*/
af = sctp_get_af_specific(addr->sa_family);
if (af && addr_len >= af->sockaddr_len)
err = __sctp_connect(sk, addr, af->sockaddr_len, flags, NULL);
}
release_sock(sk);
return err;