net, xfrm: convert xfrm_policy.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/xfrm.h b/include/net/xfrm.h
index f5272a2..e1bd1de 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -560,7 +560,7 @@
/* This lock only affects elements except for entry. */
rwlock_t lock;
- atomic_t refcnt;
+ refcount_t refcnt;
struct timer_list timer;
struct flow_cache_object flo;
@@ -816,14 +816,14 @@
static inline void xfrm_pol_hold(struct xfrm_policy *policy)
{
if (likely(policy != NULL))
- atomic_inc(&policy->refcnt);
+ refcount_inc(&policy->refcnt);
}
void xfrm_policy_destroy(struct xfrm_policy *policy);
static inline void xfrm_pol_put(struct xfrm_policy *policy)
{
- if (atomic_dec_and_test(&policy->refcnt))
+ if (refcount_dec_and_test(&policy->refcnt))
xfrm_policy_destroy(policy);
}