[PATCH 23/23] net, ax25: convert ax25_cb.refcount from atomic_t to refcount_t
From: Elena Reshetova <elena.reshetova@intel.com>
Date: 2017-03-17 12:20:57
Also in:
ceph-devel, linux-hams, linux-nfs, linux-rdma, linux-sctp, lkml
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 <redacted> Signed-off-by: Kees Cook <redacted> Signed-off-by: David Windsor <redacted> --- include/net/ax25.h | 6 +++--- net/ax25/af_ax25.c | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/include/net/ax25.h b/include/net/ax25.h
index e3467ba..c4a0cf6 100644
--- a/include/net/ax25.h
+++ b/include/net/ax25.h@@ -244,7 +244,7 @@ typedef struct ax25_cb { unsigned char window; struct timer_list timer, dtimer; struct sock *sk; /* Backlink to socket */ - atomic_t refcount; + refcount_t refcount; } ax25_cb; struct ax25_sock {
@@ -266,11 +266,11 @@ static inline struct ax25_cb *sk_to_ax25(const struct sock *sk) hlist_for_each_entry(__ax25, list, ax25_node) #define ax25_cb_hold(__ax25) \ - atomic_inc(&((__ax25)->refcount)) + refcount_inc(&((__ax25)->refcount)) static __inline__ void ax25_cb_put(ax25_cb *ax25) { - if (atomic_dec_and_test(&ax25->refcount)) { + if (refcount_dec_and_test(&ax25->refcount)) { kfree(ax25->digipeat); kfree(ax25); }
diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
index 90fcf5f..163e81f 100644
--- a/net/ax25/af_ax25.c
+++ b/net/ax25/af_ax25.c@@ -510,7 +510,7 @@ ax25_cb *ax25_create_cb(void) if ((ax25 = kzalloc(sizeof(*ax25), GFP_ATOMIC)) == NULL) return NULL; - atomic_set(&ax25->refcount, 1); + refcount_set(&ax25->refcount, 1); skb_queue_head_init(&ax25->write_queue); skb_queue_head_init(&ax25->frag_queue);
--
2.7.4