net, atm: convert lec_arp_table.usage 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/net/atm/lec.c b/net/atm/lec.c
index 7554571..093fe87 100644
--- a/net/atm/lec.c
+++ b/net/atm/lec.c
@@ -101,12 +101,12 @@ static void lec_vcc_close(struct lec_priv *priv, struct atm_vcc *vcc);
/* must be done under lec_arp_lock */
static inline void lec_arp_hold(struct lec_arp_table *entry)
{
- atomic_inc(&entry->usage);
+ refcount_inc(&entry->usage);
}
static inline void lec_arp_put(struct lec_arp_table *entry)
{
- if (atomic_dec_and_test(&entry->usage))
+ if (refcount_dec_and_test(&entry->usage))
kfree(entry);
}
@@ -1564,7 +1564,7 @@ static struct lec_arp_table *make_entry(struct lec_priv *priv,
to_return->last_used = jiffies;
to_return->priv = priv;
skb_queue_head_init(&to_return->tx_wait);
- atomic_set(&to_return->usage, 1);
+ refcount_set(&to_return->usage, 1);
return to_return;
}