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/request_sock.h | |
| parent | 14afee4b6092fde451ee17604e5f5c89da33e71e (diff) | |
| download | lwn-41c6d650f6537e55a1b53438c646fbc3f49176bf.tar.gz lwn-41c6d650f6537e55a1b53438c646fbc3f49176bf.zip | |
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/request_sock.h')
| -rw-r--r-- | include/net/request_sock.h | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/include/net/request_sock.h b/include/net/request_sock.h index 53ced67c4ae9..23e22054aa60 100644 --- a/include/net/request_sock.h +++ b/include/net/request_sock.h @@ -19,6 +19,7 @@ #include <linux/spinlock.h> #include <linux/types.h> #include <linux/bug.h> +#include <linux/refcount.h> #include <net/sock.h> @@ -89,7 +90,7 @@ reqsk_alloc(const struct request_sock_ops *ops, struct sock *sk_listener, return NULL; req->rsk_listener = NULL; if (attach_listener) { - if (unlikely(!atomic_inc_not_zero(&sk_listener->sk_refcnt))) { + if (unlikely(!refcount_inc_not_zero(&sk_listener->sk_refcnt))) { kmem_cache_free(ops->slab, req); return NULL; } @@ -100,7 +101,7 @@ reqsk_alloc(const struct request_sock_ops *ops, struct sock *sk_listener, sk_node_init(&req_to_sk(req)->sk_node); sk_tx_queue_clear(req_to_sk(req)); req->saved_syn = NULL; - atomic_set(&req->rsk_refcnt, 0); + refcount_set(&req->rsk_refcnt, 0); return req; } @@ -108,7 +109,7 @@ reqsk_alloc(const struct request_sock_ops *ops, struct sock *sk_listener, static inline void reqsk_free(struct request_sock *req) { /* temporary debugging */ - WARN_ON_ONCE(atomic_read(&req->rsk_refcnt) != 0); + WARN_ON_ONCE(refcount_read(&req->rsk_refcnt) != 0); req->rsk_ops->destructor(req); if (req->rsk_listener) @@ -119,7 +120,7 @@ static inline void reqsk_free(struct request_sock *req) static inline void reqsk_put(struct request_sock *req) { - if (atomic_dec_and_test(&req->rsk_refcnt)) + if (refcount_dec_and_test(&req->rsk_refcnt)) reqsk_free(req); } |