From 5534a51ab79f8925ee33d9830646f5e6df27eb54 Mon Sep 17 00:00:00 2001 From: "Reshetova, Elena" Date: Tue, 4 Jul 2017 15:53:20 +0300 Subject: net, x25: convert x25_neigh.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. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller --- include/net/x25.h | 6 +++--- net/x25/x25_link.c | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/include/net/x25.h b/include/net/x25.h index 1ac14006bf78..2609b57bd459 100644 --- a/include/net/x25.h +++ b/include/net/x25.h @@ -142,7 +142,7 @@ struct x25_neigh { unsigned long t20; struct timer_list t20timer; unsigned long global_facil_mask; - atomic_t refcnt; + refcount_t refcnt; }; struct x25_sock { @@ -243,12 +243,12 @@ void x25_link_free(void); /* x25_neigh.c */ static __inline__ void x25_neigh_hold(struct x25_neigh *nb) { - atomic_inc(&nb->refcnt); + refcount_inc(&nb->refcnt); } static __inline__ void x25_neigh_put(struct x25_neigh *nb) { - if (atomic_dec_and_test(&nb->refcnt)) + if (refcount_dec_and_test(&nb->refcnt)) kfree(nb); } diff --git a/net/x25/x25_link.c b/net/x25/x25_link.c index bcaa180d6a3f..e0cd04d28352 100644 --- a/net/x25/x25_link.c +++ b/net/x25/x25_link.c @@ -266,7 +266,7 @@ void x25_link_device_up(struct net_device *dev) X25_MASK_PACKET_SIZE | X25_MASK_WINDOW_SIZE; nb->t20 = sysctl_x25_restart_request_timeout; - atomic_set(&nb->refcnt, 1); + refcount_set(&nb->refcnt, 1); write_lock_bh(&x25_neigh_list_lock); list_add(&nb->node, &x25_neigh_list); -- cgit