net/hsr: Fix NULL pointer dereference on incomplete hsr_newlink() par…

…ams. If none of the slave interfaces are specified, struct nlattr *data[] may be NULL. Make sure to check for that. While I'm at it, fix the horrible error messages displayed when only one of the slave interfaces isn't specified. Signed-off-by: Arvid Brodin <[email protected]> Signed-off-by: David S. Miller <[email protected]>
niw · Jul 8, 2014 · a718dcc · a718dcc
1 parent f266a68
commit a718dcc
Showing 1 changed file with 6 additions and 2 deletions.
diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c
@@ -37,13 +37,17 @@ static int hsr_newlink(struct net *src_net, struct net_device *dev,
 	struct net_device *link[2];
 	unsigned char multicast_spec;
 
+	if (!data) {
+		netdev_info(dev, "HSR: No slave devices specified\n");
+		return -EINVAL;
+	}
 	if (!data[IFLA_HSR_SLAVE1]) {
-		netdev_info(dev, "IFLA_HSR_SLAVE1 missing!\n");
+		netdev_info(dev, "HSR: Slave1 device not specified\n");
 		return -EINVAL;
 	}
 	link[0] = __dev_get_by_index(src_net, nla_get_u32(data[IFLA_HSR_SLAVE1]));
 	if (!data[IFLA_HSR_SLAVE2]) {
-		netdev_info(dev, "IFLA_HSR_SLAVE2 missing!\n");
+		netdev_info(dev, "HSR: Slave2 device not specified\n");
 		return -EINVAL;
 	}
 	link[1] = __dev_get_by_index(src_net, nla_get_u32(data[IFLA_HSR_SLAVE2]));