net, x25: convert x25_neigh.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/x25.h b/include/net/x25.h
index 1ac1400..2609b57 100644
--- a/include/net/x25.h
+++ b/include/net/x25.h
@@ -142,7 +142,7 @@
unsigned long t20;
struct timer_list t20timer;
unsigned long global_facil_mask;
- atomic_t refcnt;
+ refcount_t refcnt;
};
struct x25_sock {
@@ -243,12 +243,12 @@
/* x25_neigh.c */
static __inline__ void x25_neigh_hold(struct x25_neigh *nb)
{
- atomic_inc(&nb->refcnt);
+ refcount_inc(&nb->refcnt);
}
static __inline__ void x25_neigh_put(struct x25_neigh *nb)
{
- if (atomic_dec_and_test(&nb->refcnt))
+ if (refcount_dec_and_test(&nb->refcnt))
kfree(nb);
}
diff --git a/net/x25/x25_link.c b/net/x25/x25_link.c
index bcaa180..e0cd04d 100644
--- a/net/x25/x25_link.c
+++ b/net/x25/x25_link.c
@@ -266,7 +266,7 @@
X25_MASK_PACKET_SIZE |
X25_MASK_WINDOW_SIZE;
nb->t20 = sysctl_x25_restart_request_timeout;
- atomic_set(&nb->refcnt, 1);
+ refcount_set(&nb->refcnt, 1);
write_lock_bh(&x25_neigh_list_lock);
list_add(&nb->node, &x25_neigh_list);