net: convert sock.sk_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.
This patch uses refcount_inc_not_zero() instead of
atomic_inc_not_zero_hint() due to absense of a _hint()
version of refcount API. If the hint() version must
be used, we might need to revisit API.
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/inet_hashtables.h b/include/net/inet_hashtables.h
index 1178931..b9e6e0e 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -32,7 +32,7 @@
#include <net/tcp_states.h>
#include <net/netns/hash.h>
-#include <linux/atomic.h>
+#include <linux/refcount.h>
#include <asm/byteorder.h>
/* This is for all connections with a full identity, no wildcards.
@@ -334,7 +334,7 @@ static inline struct sock *inet_lookup(struct net *net,
sk = __inet_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
dport, dif, &refcounted);
- if (sk && !refcounted && !atomic_inc_not_zero(&sk->sk_refcnt))
+ if (sk && !refcounted && !refcount_inc_not_zero(&sk->sk_refcnt))
sk = NULL;
return sk;
}