net, llc: convert llc_sap.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/llc.h b/include/net/llc.h
index e8e61d4..dc35f25 100644
--- a/include/net/llc.h
+++ b/include/net/llc.h
@@ -55,7 +55,7 @@ struct llc_sap {
unsigned char state;
unsigned char p_bit;
unsigned char f_bit;
- atomic_t refcnt;
+ refcount_t refcnt;
int (*rcv_func)(struct sk_buff *skb,
struct net_device *dev,
struct packet_type *pt,
@@ -113,14 +113,14 @@ struct llc_sap *llc_sap_open(unsigned char lsap,
struct net_device *orig_dev));
static inline void llc_sap_hold(struct llc_sap *sap)
{
- atomic_inc(&sap->refcnt);
+ refcount_inc(&sap->refcnt);
}
void llc_sap_close(struct llc_sap *sap);
static inline void llc_sap_put(struct llc_sap *sap)
{
- if (atomic_dec_and_test(&sap->refcnt))
+ if (refcount_dec_and_test(&sap->refcnt))
llc_sap_close(sap);
}
