[AX.25]: Fix unchecked ax25_listen_register uses

Fix ax25_listen_register to return something that's a sane error code,
then all callers to use it.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 24 insertions, 10 deletions

diff --git a/net/ax25/ax25_iface.c b/net/ax25/ax25_iface.c
index dd9b7fee3df8..51e293420b7f 100644
--- a/net/ax25/ax25_iface.c
+++ b/net/ax25/ax25_iface.c
@@ -154,7 +154,7 @@ int ax25_listen_register(ax25_address *callsign, struct net_device *dev)
                 return 0;
 
         if ((listen = kmalloc(sizeof(*listen), GFP_ATOMIC)) == NULL)
-                return 0;
+                return -ENOMEM;
 
         listen->callsign = *callsign;
         listen->dev      = dev;
@@ -164,7 +164,7 @@ int ax25_listen_register(ax25_address *callsign, struct net_device *dev)
         listen_list  = listen;
         spin_unlock_bh(&listen_lock);
 
-        return 1;
+        return 0;
 }
 
 EXPORT_SYMBOL(ax25_listen_register);
@@ -225,7 +225,8 @@ int ax25_listen_mine(ax25_address *callsign, struct net_device *dev)
 
         spin_lock_bh(&listen_lock);
         for (listen = listen_list; listen != NULL; listen = listen->next)
-                if (ax25cmp(&listen->callsign, callsign) == 0 && (listen->dev == dev || listen->dev == NULL)) {
+                if (ax25cmp(&listen->callsign, callsign) == 0 &&
+                    (listen->dev == dev || listen->dev == NULL)) {
                         spin_unlock_bh(&listen_lock);
                         return 1;
         }
diff --git a/net/netrom/nr_dev.c b/net/netrom/nr_dev.c
index 9b8eb54971ab..4700d5225b78 100644
--- a/net/netrom/nr_dev.c
+++ b/net/netrom/nr_dev.c
@@ -128,25 +128,37 @@ static int nr_header(struct sk_buff *skb, struct net_device *dev, unsigned short
         return -37;
 }
 
-static int nr_set_mac_address(struct net_device *dev, void *addr)
+static int __must_check nr_set_mac_address(struct net_device *dev, void *addr)
 {
         struct sockaddr *sa = addr;
+        int err;
+
+        if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len))
+                return 0;
+
+        if (dev->flags & IFF_UP) {
+                err = ax25_listen_register((ax25_address *)sa->sa_data, NULL);
+                if (err)
+                        return err;
 
-        if (dev->flags & IFF_UP)
                 ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
+        }
 
         memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
 
-        if (dev->flags & IFF_UP)
-                ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
-
         return 0;
 }
 
 static int nr_open(struct net_device *dev)
 {
+        int err;
+
+        err = ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
+        if (err)
+                return err;
+
         netif_start_queue(dev);
-        ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
+
         return 0;
 }
 
diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c
index 1605069e5db1..09f8a06bf806 100644
--- a/net/rose/af_rose.c
+++ b/net/rose/af_rose.c
@@ -1314,7 +1314,8 @@ static int rose_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
                 if (copy_from_user(&rose_callsign, argp, sizeof(ax25_address)))
                         return -EFAULT;
                 if (ax25cmp(&rose_callsign, &null_ax25_address) != 0)
-                        ax25_listen_register(&rose_callsign, NULL);
+                        return ax25_listen_register(&rose_callsign, NULL);
+
                 return 0;
 
         case SIOCRSGL2CALL: