diff --git a/include/net/ax25.h b/include/net/ax25.h index e602f8177ebfbf..b507ce2b19523e 100644 --- a/include/net/ax25.h +++ b/include/net/ax25.h @@ -199,6 +199,18 @@ static inline void ax25_hold_route(ax25_route *ax25_rt) void __ax25_put_route(ax25_route *ax25_rt); +extern rwlock_t ax25_route_lock; + +static inline void ax25_route_lock_use(void) +{ + read_lock(&ax25_route_lock); +} + +static inline void ax25_route_lock_unuse(void) +{ + read_unlock(&ax25_route_lock); +} + static inline void ax25_put_route(ax25_route *ax25_rt) { if (atomic_dec_and_test(&ax25_rt->refcount)) diff --git a/net/ax25/ax25_ip.c b/net/ax25/ax25_ip.c index 2fa3be96510161..cd9a24e5b97a09 100644 --- a/net/ax25/ax25_ip.c +++ b/net/ax25/ax25_ip.c @@ -114,6 +114,7 @@ netdev_tx_t ax25_ip_xmit(struct sk_buff *skb) dst = (ax25_address *)(bp + 1); src = (ax25_address *)(bp + 8); + ax25_route_lock_use(); route = ax25_get_route(dst, NULL); if (route) { digipeat = route->digipeat; @@ -206,9 +207,8 @@ netdev_tx_t ax25_ip_xmit(struct sk_buff *skb) ax25_queue_xmit(skb, dev); put: - if (route) - ax25_put_route(route); + ax25_route_lock_unuse(); return NETDEV_TX_OK; } diff --git a/net/ax25/ax25_route.c b/net/ax25/ax25_route.c index d39097737e387a..149f82bd83fdba 100644 --- a/net/ax25/ax25_route.c +++ b/net/ax25/ax25_route.c @@ -40,7 +40,7 @@ #include static ax25_route *ax25_route_list; -static DEFINE_RWLOCK(ax25_route_lock); +DEFINE_RWLOCK(ax25_route_lock); void ax25_rt_device_down(struct net_device *dev) { @@ -349,6 +349,7 @@ const struct file_operations ax25_route_fops = { * Find AX.25 route * * Only routes with a reference count of zero can be destroyed. + * Must be called with ax25_route_lock read locked. */ ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev) { @@ -356,7 +357,6 @@ ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev) ax25_route *ax25_def_rt = NULL; ax25_route *ax25_rt; - read_lock(&ax25_route_lock); /* * Bind to the physical interface we heard them on, or the default * route if none is found; @@ -379,11 +379,6 @@ ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev) if (ax25_spe_rt != NULL) ax25_rt = ax25_spe_rt; - if (ax25_rt != NULL) - ax25_hold_route(ax25_rt); - - read_unlock(&ax25_route_lock); - return ax25_rt; } @@ -414,9 +409,12 @@ int ax25_rt_autobind(ax25_cb *ax25, ax25_address *addr) ax25_route *ax25_rt; int err = 0; - if ((ax25_rt = ax25_get_route(addr, NULL)) == NULL) + ax25_route_lock_use(); + ax25_rt = ax25_get_route(addr, NULL); + if (!ax25_rt) { + ax25_route_lock_unuse(); return -EHOSTUNREACH; - + } if ((ax25->ax25_dev = ax25_dev_ax25dev(ax25_rt->dev)) == NULL) { err = -EHOSTUNREACH; goto put; @@ -451,8 +449,7 @@ int ax25_rt_autobind(ax25_cb *ax25, ax25_address *addr) } put: - ax25_put_route(ax25_rt); - + ax25_route_lock_unuse(); return err; }