net, ax25: convert ax25_cb.refcount 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/ax25.h b/include/net/ax25.h
index e3467ba..c4a0cf6 100644
--- a/include/net/ax25.h
+++ b/include/net/ax25.h
@@ -244,7 +244,7 @@ typedef struct ax25_cb {
unsigned char window;
struct timer_list timer, dtimer;
struct sock *sk; /* Backlink to socket */
- atomic_t refcount;
+ refcount_t refcount;
} ax25_cb;
struct ax25_sock {
@@ -266,11 +266,11 @@ static inline struct ax25_cb *sk_to_ax25(const struct sock *sk)
hlist_for_each_entry(__ax25, list, ax25_node)
#define ax25_cb_hold(__ax25) \
- atomic_inc(&((__ax25)->refcount))
+ refcount_inc(&((__ax25)->refcount))
static __inline__ void ax25_cb_put(ax25_cb *ax25)
{
- if (atomic_dec_and_test(&ax25->refcount)) {
+ if (refcount_dec_and_test(&ax25->refcount)) {
kfree(ax25->digipeat);
kfree(ax25);
}