dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

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>
This commit is contained in:
David S. Miller 2011-05-08 13:39:01 -07:00
parent da905bd1d5
commit 2f16270f41
1 changed files with 15 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
net/l2tp/l2tp_ip.c
View File

@ -311,6 +311,8 @@ static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len
if (lsa->l2tp_family != AF_INET)
goto out;
lock_sock(sk);
sk_dst_reset(sk);
oif = sk->sk_bound_dev_if;
@ -356,6 +358,7 @@ static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len
rc = 0;
out:
release_sock(sk);
return rc;
}
@ -420,18 +423,23 @@ static int l2tp_ip_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *m
int connected = 0;
__be32 daddr;
lock_sock(sk);
rc = -ENOTCONN;
if (sock_flag(sk, SOCK_DEAD))
return -ENOTCONN;
goto out;
/* Get and verify the address. */
if (msg->msg_name) {
struct sockaddr_l2tpip *lip = (struct sockaddr_l2tpip *) msg->msg_name;
rc = -EINVAL;
if (msg->msg_namelen < sizeof(*lip))
return -EINVAL;
goto out;
if (lip->l2tp_family != AF_INET) {
rc = -EAFNOSUPPORT;
if (lip->l2tp_family != AF_UNSPEC)
return -EAFNOSUPPORT;
goto out;
}
daddr = lip->l2tp_addr.s_addr;
@ -510,12 +518,15 @@ error:
lsa->tx_errors++;
}
out:
release_sock(sk);
return rc;
no_route:
IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
kfree_skb(skb);
return -EHOSTUNREACH;
rc = -EHOSTUNREACH;
goto out;
}
static int l2tp_ip_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,