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| author | Reshetova, Elena <elena.reshetova@intel.com> | 2017-07-04 15:52:57 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-07-04 22:35:15 +0100 |
| commit | fbea9e0760bf17e681b9bfc25b97b408708b9ff2 (patch) | |
| tree | a4c8c287dfb2452e1ea5c94e089350cf93b948e6 /net/l2tp/l2tp_core.c | |
| parent | 58951dde05fdac96a9d30805d8fa5d124dd4f92c (diff) | |
| download | linux-fbea9e0760bf17e681b9bfc25b97b408708b9ff2.tar.gz linux-fbea9e0760bf17e681b9bfc25b97b408708b9ff2.tar.bz2 linux-fbea9e0760bf17e681b9bfc25b97b408708b9ff2.zip | |
net, l2tp: convert l2tp_tunnel.ref_count 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>
Diffstat (limited to 'net/l2tp/l2tp_core.c')
| -rw-r--r-- | net/l2tp/l2tp_core.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index fa0342574b89..203c4aa3e916 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -132,12 +132,12 @@ static inline struct l2tp_net *l2tp_pernet(const struct net *net) */ static inline void l2tp_tunnel_inc_refcount_1(struct l2tp_tunnel *tunnel) { - atomic_inc(&tunnel->ref_count); + refcount_inc(&tunnel->ref_count); } static inline void l2tp_tunnel_dec_refcount_1(struct l2tp_tunnel *tunnel) { - if (atomic_dec_and_test(&tunnel->ref_count)) + if (refcount_dec_and_test(&tunnel->ref_count)) l2tp_tunnel_free(tunnel); } #ifdef L2TP_REFCNT_DEBUG @@ -145,14 +145,14 @@ static inline void l2tp_tunnel_dec_refcount_1(struct l2tp_tunnel *tunnel) do { \ pr_debug("l2tp_tunnel_inc_refcount: %s:%d %s: cnt=%d\n", \ __func__, __LINE__, (_t)->name, \ - atomic_read(&_t->ref_count)); \ + refcount_read(&_t->ref_count)); \ l2tp_tunnel_inc_refcount_1(_t); \ } while (0) #define l2tp_tunnel_dec_refcount(_t) \ do { \ pr_debug("l2tp_tunnel_dec_refcount: %s:%d %s: cnt=%d\n", \ __func__, __LINE__, (_t)->name, \ - atomic_read(&_t->ref_count)); \ + refcount_read(&_t->ref_count)); \ l2tp_tunnel_dec_refcount_1(_t); \ } while (0) #else @@ -1353,7 +1353,7 @@ static void l2tp_udp_encap_destroy(struct sock *sk) */ static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel) { - BUG_ON(atomic_read(&tunnel->ref_count) != 0); + BUG_ON(refcount_read(&tunnel->ref_count) != 0); BUG_ON(tunnel->sock != NULL); l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: free...\n", tunnel->name); kfree_rcu(tunnel, rcu); @@ -1667,7 +1667,7 @@ int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32 /* Bump the reference count. The tunnel context is deleted * only when this drops to zero. Must be done before list insertion */ - l2tp_tunnel_inc_refcount(tunnel); + refcount_set(&tunnel->ref_count, 1); spin_lock_bh(&pn->l2tp_tunnel_list_lock); list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list); spin_unlock_bh(&pn->l2tp_tunnel_list_lock); @@ -1706,7 +1706,7 @@ void l2tp_session_free(struct l2tp_session *session) { struct l2tp_tunnel *tunnel = session->tunnel; - BUG_ON(atomic_read(&session->ref_count) != 0); + BUG_ON(refcount_read(&session->ref_count) != 0); if (tunnel) { BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); |