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path: root/drivers/net/tun.c
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Diffstat (limited to 'drivers/net/tun.c')
-rw-r--r--drivers/net/tun.c68
1 files changed, 25 insertions, 43 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 504f7f1cad94..af372d0957fe 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -180,7 +180,6 @@ struct tun_struct {
int debug;
#endif
spinlock_t lock;
- struct kmem_cache *flow_cache;
struct hlist_head flows[TUN_NUM_FLOW_ENTRIES];
struct timer_list flow_gc_timer;
unsigned long ageing_time;
@@ -209,8 +208,8 @@ static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun,
struct hlist_head *head,
u32 rxhash, u16 queue_index)
{
- struct tun_flow_entry *e = kmem_cache_alloc(tun->flow_cache,
- GFP_ATOMIC);
+ struct tun_flow_entry *e = kmalloc(sizeof(*e), GFP_ATOMIC);
+
if (e) {
tun_debug(KERN_INFO, tun, "create flow: hash %u index %u\n",
rxhash, queue_index);
@@ -223,19 +222,12 @@ static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun,
return e;
}
-static void tun_flow_free(struct rcu_head *head)
-{
- struct tun_flow_entry *e
- = container_of(head, struct tun_flow_entry, rcu);
- kmem_cache_free(e->tun->flow_cache, e);
-}
-
static void tun_flow_delete(struct tun_struct *tun, struct tun_flow_entry *e)
{
tun_debug(KERN_INFO, tun, "delete flow: hash %u index %u\n",
e->rxhash, e->queue_index);
hlist_del_rcu(&e->hash_link);
- call_rcu(&e->rcu, tun_flow_free);
+ kfree_rcu(e, rcu);
}
static void tun_flow_flush(struct tun_struct *tun)
@@ -412,8 +404,8 @@ static void __tun_detach(struct tun_file *tfile, bool clean)
struct tun_struct *tun;
struct net_device *dev;
- tun = rcu_dereference_protected(tfile->tun,
- lockdep_rtnl_is_held());
+ tun = rtnl_dereference(tfile->tun);
+
if (tun) {
u16 index = tfile->queue_index;
BUG_ON(index >= tun->numqueues);
@@ -422,8 +414,7 @@ static void __tun_detach(struct tun_file *tfile, bool clean)
rcu_assign_pointer(tun->tfiles[index],
tun->tfiles[tun->numqueues - 1]);
rcu_assign_pointer(tfile->tun, NULL);
- ntfile = rcu_dereference_protected(tun->tfiles[index],
- lockdep_rtnl_is_held());
+ ntfile = rtnl_dereference(tun->tfiles[index]);
ntfile->queue_index = index;
--tun->numqueues;
@@ -437,8 +428,10 @@ static void __tun_detach(struct tun_file *tfile, bool clean)
/* Drop read queue */
skb_queue_purge(&tfile->sk.sk_receive_queue);
tun_set_real_num_queues(tun);
- } else if (tfile->detached && clean)
+ } else if (tfile->detached && clean) {
tun = tun_enable_queue(tfile);
+ sock_put(&tfile->sk);
+ }
if (clean) {
if (tun && tun->numqueues == 0 && tun->numdisabled == 0 &&
@@ -466,8 +459,7 @@ static void tun_detach_all(struct net_device *dev)
int i, n = tun->numqueues;
for (i = 0; i < n; i++) {
- tfile = rcu_dereference_protected(tun->tfiles[i],
- lockdep_rtnl_is_held());
+ tfile = rtnl_dereference(tun->tfiles[i]);
BUG_ON(!tfile);
wake_up_all(&tfile->wq.wait);
rcu_assign_pointer(tfile->tun, NULL);
@@ -477,8 +469,7 @@ static void tun_detach_all(struct net_device *dev)
synchronize_net();
for (i = 0; i < n; i++) {
- tfile = rcu_dereference_protected(tun->tfiles[i],
- lockdep_rtnl_is_held());
+ tfile = rtnl_dereference(tun->tfiles[i]);
/* Drop read queue */
skb_queue_purge(&tfile->sk.sk_receive_queue);
sock_put(&tfile->sk);
@@ -489,6 +480,9 @@ static void tun_detach_all(struct net_device *dev)
sock_put(&tfile->sk);
}
BUG_ON(tun->numdisabled != 0);
+
+ if (tun->flags & TUN_PERSIST)
+ module_put(THIS_MODULE);
}
static int tun_attach(struct tun_struct *tun, struct file *file)
@@ -497,7 +491,7 @@ static int tun_attach(struct tun_struct *tun, struct file *file)
int err;
err = -EINVAL;
- if (rcu_dereference_protected(tfile->tun, lockdep_rtnl_is_held()))
+ if (rtnl_dereference(tfile->tun))
goto out;
err = -EBUSY;
@@ -833,12 +827,6 @@ static int tun_flow_init(struct tun_struct *tun)
{
int i;
- tun->flow_cache = kmem_cache_create("tun_flow_cache",
- sizeof(struct tun_flow_entry), 0, 0,
- NULL);
- if (!tun->flow_cache)
- return -ENOMEM;
-
for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++)
INIT_HLIST_HEAD(&tun->flows[i]);
@@ -854,10 +842,6 @@ static void tun_flow_uninit(struct tun_struct *tun)
{
del_timer_sync(&tun->flow_gc_timer);
tun_flow_flush(tun);
-
- /* Wait for completion of call_rcu()'s */
- rcu_barrier();
- kmem_cache_destroy(tun->flow_cache);
}
/* Initialize net device. */
@@ -1562,6 +1546,9 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
struct net_device *dev;
int err;
+ if (tfile->detached)
+ return -EINVAL;
+
dev = __dev_get_by_name(net, ifr->ifr_name);
if (dev) {
if (ifr->ifr_flags & IFF_TUN_EXCL)
@@ -1756,8 +1743,7 @@ static void tun_detach_filter(struct tun_struct *tun, int n)
struct tun_file *tfile;
for (i = 0; i < n; i++) {
- tfile = rcu_dereference_protected(tun->tfiles[i],
- lockdep_rtnl_is_held());
+ tfile = rtnl_dereference(tun->tfiles[i]);
sk_detach_filter(tfile->socket.sk);
}
@@ -1770,8 +1756,7 @@ static int tun_attach_filter(struct tun_struct *tun)
struct tun_file *tfile;
for (i = 0; i < tun->numqueues; i++) {
- tfile = rcu_dereference_protected(tun->tfiles[i],
- lockdep_rtnl_is_held());
+ tfile = rtnl_dereference(tun->tfiles[i]);
ret = sk_attach_filter(&tun->fprog, tfile->socket.sk);
if (ret) {
tun_detach_filter(tun, i);
@@ -1789,8 +1774,7 @@ static void tun_set_sndbuf(struct tun_struct *tun)
int i;
for (i = 0; i < tun->numqueues; i++) {
- tfile = rcu_dereference_protected(tun->tfiles[i],
- lockdep_rtnl_is_held());
+ tfile = rtnl_dereference(tun->tfiles[i]);
tfile->socket.sk->sk_sndbuf = tun->sndbuf;
}
}
@@ -1807,13 +1791,10 @@ static int tun_set_queue(struct file *file, struct ifreq *ifr)
tun = tfile->detached;
if (!tun)
ret = -EINVAL;
- else if (tun_not_capable(tun))
- ret = -EPERM;
else
ret = tun_attach(tun, file);
} else if (ifr->ifr_flags & IFF_DETACH_QUEUE) {
- tun = rcu_dereference_protected(tfile->tun,
- lockdep_rtnl_is_held());
+ tun = rtnl_dereference(tfile->tun);
if (!tun || !(tun->flags & TUN_TAP_MQ))
ret = -EINVAL;
else
@@ -1898,10 +1879,11 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
/* Disable/Enable persist mode. Keep an extra reference to the
* module to prevent the module being unprobed.
*/
- if (arg) {
+ if (arg && !(tun->flags & TUN_PERSIST)) {
tun->flags |= TUN_PERSIST;
__module_get(THIS_MODULE);
- } else {
+ }
+ if (!arg && (tun->flags & TUN_PERSIST)) {
tun->flags &= ~TUN_PERSIST;
module_put(THIS_MODULE);
}