[275/289] econet: disallow NULL remote addr for sendmsg(), fixes CVE-2010-3849

Greg KH
2010-12-08T01:04:17Z

From: Phil Blundell <philb@gnu.org>

commit fa0e846494792e722d817b9d3d625a4ef4896c96 upstream.

Later parts of econet_sendmsg() rely on saddr != NULL, so return early
with EINVAL if NULL was passed otherwise an oops may occur.

Signed-off-by: Phil Blundell <philb@gnu.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
net/econet/af_econet.c | 26 ++++++++------------------
1 file changed, 8 insertions(+), 18 deletions(-)

--- a/net/econet/af_econet.c
+++ b/net/econet/af_econet.c
@@ -297,23 +297,14 @@ static int econet_sendmsg(struct kiocb *

mutex_lock(&econet_mutex);

- if (saddr == NULL) {
- struct econet_sock *eo = ec_sk(sk);
-
- addr.station = eo->station;
- addr.net = eo->net;
- port = eo->port;
- cb = eo->cb;
- } else {
- if (msg->msg_namelen < sizeof(struct sockaddr_ec)) {
- mutex_unlock(&econet_mutex);
- return -EINVAL;
- }
- addr.station = saddr->addr.station;
- addr.net = saddr->addr.net;
- port = saddr->port;
- cb = saddr->cb;
- }
+ if (saddr == NULL || msg->msg_namelen < sizeof(struct sockaddr_ec)) {
+ mutex_unlock(&econet_mutex);
+ return -EINVAL;
+ }
+ addr.station = saddr->addr.station;
+ addr.net = saddr->addr.net;
+ port = saddr->port;
+ cb = saddr->cb;

/* Look for a device with the right network number. */
dev = net2dev_map[addr.net];
@@ -351,7 +342,6 @@ static int econet_sendmsg(struct kiocb *

eb = (struct ec_cb *)&skb->cb;

- /* BUG: saddr may be NULL */
eb->cookie = saddr->cookie;
eb->sec = *saddr;
eb->sent = ec_tx_done;