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	l2tp: Fix locking in l2tp_ip.c
Both l2tp_ip_connect() and l2tp_ip_sendmsg() must take the socket lock. They both modify socket state non-atomically, and in particular l2tp_ip_sendmsg() increments socket private counters without using atomic operations. Signed-off-by: David S. Miller <davem@davemloft.net>
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					 1 changed files with 15 additions and 4 deletions
				
			
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			@ -311,6 +311,8 @@ static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len
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	if (lsa->l2tp_family != AF_INET)
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		goto out;
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	lock_sock(sk);
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	sk_dst_reset(sk);
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	oif = sk->sk_bound_dev_if;
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			@ -356,6 +358,7 @@ static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len
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	rc = 0;
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out:
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	release_sock(sk);
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	return rc;
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}
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			@ -420,18 +423,23 @@ static int l2tp_ip_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *m
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	int connected = 0;
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	__be32 daddr;
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	lock_sock(sk);
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	rc = -ENOTCONN;
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	if (sock_flag(sk, SOCK_DEAD))
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		return -ENOTCONN;
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		goto out;
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	/* Get and verify the address. */
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	if (msg->msg_name) {
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		struct sockaddr_l2tpip *lip = (struct sockaddr_l2tpip *) msg->msg_name;
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		rc = -EINVAL;
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		if (msg->msg_namelen < sizeof(*lip))
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			return -EINVAL;
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			goto out;
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		if (lip->l2tp_family != AF_INET) {
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			rc = -EAFNOSUPPORT;
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			if (lip->l2tp_family != AF_UNSPEC)
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				return -EAFNOSUPPORT;
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				goto out;
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		}
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		daddr = lip->l2tp_addr.s_addr;
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			@ -510,12 +518,15 @@ static int l2tp_ip_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *m
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		lsa->tx_errors++;
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	}
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out:
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	release_sock(sk);
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	return rc;
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no_route:
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	IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
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	kfree_skb(skb);
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	return -EHOSTUNREACH;
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	rc = -EHOSTUNREACH;
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	goto out;
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}
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static int l2tp_ip_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
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