net: convert neighbour.refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/arp.h b/include/net/arp.h
index 65619a2..17d90e4 100644
--- a/include/net/arp.h
+++ b/include/net/arp.h
@@ -28,7 +28,7 @@ static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32
rcu_read_lock_bh();
n = __ipv4_neigh_lookup_noref(dev, key);
- if (n && !atomic_inc_not_zero(&n->refcnt))
+ if (n && !refcount_inc_not_zero(&n->refcnt))
n = NULL;
rcu_read_unlock_bh();
diff --git a/include/net/ndisc.h b/include/net/ndisc.h
index 1036c90..31b1bb1 100644
--- a/include/net/ndisc.h
+++ b/include/net/ndisc.h
@@ -384,7 +384,7 @@ static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, cons
rcu_read_lock_bh();
n = __ipv6_neigh_lookup_noref(dev, pkey);
- if (n && !atomic_inc_not_zero(&n->refcnt))
+ if (n && !refcount_inc_not_zero(&n->refcnt))
n = NULL;
rcu_read_unlock_bh();
diff --git a/include/net/neighbour.h b/include/net/neighbour.h
index 639b675..e5ee739 100644
--- a/include/net/neighbour.h
+++ b/include/net/neighbour.h
@@ -17,6 +17,7 @@
*/
#include <linux/atomic.h>
+#include <linux/refcount.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/rcupdate.h>
@@ -137,7 +138,7 @@ struct neighbour {
unsigned long confirmed;
unsigned long updated;
rwlock_t lock;
- atomic_t refcnt;
+ refcount_t refcnt;
struct sk_buff_head arp_queue;
unsigned int arp_queue_len_bytes;
struct timer_list timer;
@@ -410,18 +411,18 @@ static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
static inline void neigh_release(struct neighbour *neigh)
{
- if (atomic_dec_and_test(&neigh->refcnt))
+ if (refcount_dec_and_test(&neigh->refcnt))
neigh_destroy(neigh);
}
static inline struct neighbour * neigh_clone(struct neighbour *neigh)
{
if (neigh)
- atomic_inc(&neigh->refcnt);
+ refcount_inc(&neigh->refcnt);
return neigh;
}
-#define neigh_hold(n) atomic_inc(&(n)->refcnt)
+#define neigh_hold(n) refcount_inc(&(n)->refcnt)
static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
{