[PATCH 2/6]NET:AX25:ROSE Add device use counting for ROSE neighbour lists

[Richard Stearn]

Subject: [PATCH 2/6]NET:AX25:ROSE Add  device use counting for ROSE neighbour 
lists
Adds device use counting for ROSE neighbour lists

Signed-off-by: Richard Stearn <rich...@rns-stearn.demon.co.uk>
---
 net/rose/rose_route.c |   15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/net/rose/rose_route.c b/net/rose/rose_route.c
index 96ed06c..56e53d5 100644
--- a/net/rose/rose_route.c
+++ b/net/rose/rose_route.c
@@ -183,6 +183,7 @@ static int __must_check rose_add_node(struct 
rose_route_struct *rose_route,
                        }
                }
                rose_neigh->count++;
+               dev_hold(rose_neigh->dev);
 
                goto out;
        }
@@ -190,6 +191,7 @@ static int __must_check rose_add_node(struct 
rose_route_struct *rose_route,
        /* We have space, slot it in */
        if (rose_node->count < 3) {
                rose_node->neighbour[rose_node->count] = rose_neigh;
+               dev_hold(rose_neigh->dev);
                rose_node->count++;
                rose_neigh->count++;
        }
@@ -335,6 +337,7 @@ static int rose_del_node(struct rose_route_struct 
*rose_route,
        for (i = 0; i < rose_node->count; i++) {
                if (rose_node->neighbour[i] == rose_neigh) {
                        rose_neigh->count--;
+                       dev_put(rose_neigh->dev);
 
                        if (rose_neigh->count == 0 && 
atomic_read(&rose_neigh->use) == 0)
                                rose_remove_neigh(rose_neigh);
@@ -594,12 +597,13 @@ static struct net_device *rose_ax25_dev_find(char 
*devname)
 {
        struct net_device *dev;
 
-       if ((dev = __dev_get_by_name(&init_net, devname)) == NULL)
+       if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
                return NULL;
 
        if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
                return dev;
 
+       dev_put(dev);
        return NULL;
 }
 
@@ -616,6 +620,8 @@ struct net_device *rose_dev_first(void)
                        if (first == NULL || strncmp(dev->name, first->name, 3) 
< 0)
                                first = dev;
        }
+       if (first)
+               dev_hold(first);
        rcu_read_unlock();
 
        return first;
@@ -734,15 +740,16 @@ int rose_rt_ioctl(unsigned int cmd, void __user *arg)
        case SIOCADDRT:
                if (copy_from_user(&rose_route, arg, sizeof(struct 
rose_route_struct)))
                        return -EFAULT;
-               if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
-                       return -EINVAL;
                if (rose_dev_exists(&rose_route.address)) /* Can't add routes 
to ourself */
                        return -EINVAL;
                if (rose_route.mask > 10) /* Mask can't be more than 10 digits 
*/
                        return -EINVAL;
                if (rose_route.ndigis > AX25_MAX_DIGIS)
                        return -EINVAL;
+               if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
+                       return -EINVAL;
                err = rose_add_node(&rose_route, dev);
+               dev_put(dev);
                return err;
 
        case SIOCDELRT:
@@ -751,6 +758,7 @@ int rose_rt_ioctl(unsigned int cmd, void __user *arg)
                if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
                        return -EINVAL;
                err = rose_del_node(&rose_route, dev);
+               dev_put(dev);
                return err;
 
        case SIOCRSCLRRT:
@@ -844,6 +852,7 @@ void rose_link_device_down(struct net_device *dev)
                if (rose_neigh->dev == dev) {
                        rose_del_route_by_neigh(rose_neigh);
                        rose_kill_by_neigh(rose_neigh);
+                       dev_put(dev);
                }
        }
 }