diff options
author | Reshetova, Elena <elena.reshetova@intel.com> | 2017-06-30 13:08:01 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2017-07-01 07:39:08 -0700 |
commit | 41c6d650f6537e55a1b53438c646fbc3f49176bf (patch) | |
tree | d7fb3d5a2f1b3fb0fe76fa010141be563488d36b /include/net/sock.h | |
parent | 14afee4b6092fde451ee17604e5f5c89da33e71e (diff) |
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>
Diffstat (limited to 'include/net/sock.h')
-rw-r--r-- | include/net/sock.h | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 5284e50fc81a..60200f4f4028 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -66,6 +66,7 @@ #include <linux/poll.h> #include <linux/atomic.h> +#include <linux/refcount.h> #include <net/dst.h> #include <net/checksum.h> #include <net/tcp_states.h> @@ -219,7 +220,7 @@ struct sock_common { u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ }; - atomic_t skc_refcnt; + refcount_t skc_refcnt; /* private: */ int skc_dontcopy_end[0]; union { @@ -611,7 +612,7 @@ static inline bool __sk_del_node_init(struct sock *sk) static __always_inline void sock_hold(struct sock *sk) { - atomic_inc(&sk->sk_refcnt); + refcount_inc(&sk->sk_refcnt); } /* Ungrab socket in the context, which assumes that socket refcnt @@ -619,7 +620,7 @@ static __always_inline void sock_hold(struct sock *sk) */ static __always_inline void __sock_put(struct sock *sk) { - atomic_dec(&sk->sk_refcnt); + refcount_dec(&sk->sk_refcnt); } static inline bool sk_del_node_init(struct sock *sk) @@ -628,7 +629,7 @@ static inline bool sk_del_node_init(struct sock *sk) if (rc) { /* paranoid for a while -acme */ - WARN_ON(atomic_read(&sk->sk_refcnt) == 1); + WARN_ON(refcount_read(&sk->sk_refcnt) == 1); __sock_put(sk); } return rc; @@ -650,7 +651,7 @@ static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) if (rc) { /* paranoid for a while -acme */ - WARN_ON(atomic_read(&sk->sk_refcnt) == 1); + WARN_ON(refcount_read(&sk->sk_refcnt) == 1); __sock_put(sk); } return rc; @@ -1144,9 +1145,9 @@ static inline void sk_refcnt_debug_dec(struct sock *sk) static inline void sk_refcnt_debug_release(const struct sock *sk) { - if (atomic_read(&sk->sk_refcnt) != 1) + if (refcount_read(&sk->sk_refcnt) != 1) printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", - sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt)); + sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt)); } #else /* SOCK_REFCNT_DEBUG */ #define sk_refcnt_debug_inc(sk) do { } while (0) @@ -1636,7 +1637,7 @@ void sock_init_data(struct socket *sock, struct sock *sk); /* Ungrab socket and destroy it, if it was the last reference. */ static inline void sock_put(struct sock *sk) { - if (atomic_dec_and_test(&sk->sk_refcnt)) + if (refcount_dec_and_test(&sk->sk_refcnt)) sk_free(sk); } /* Generic version of sock_put(), dealing with all sockets |