Return-Path: Received: from mga03.intel.com ([134.134.136.65]:43703 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752686AbdGDMy5 (ORCPT ); Tue, 4 Jul 2017 08:54:57 -0400 From: Elena Reshetova To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-decnet-user@lists.sourceforge.net, davem@davemloft.net, jmorris@namei.org, kaber@trash.net, yoshfuji@linux-ipv6.org, kuznet@ms2.inr.ac.ru, 3chas3@gmail.com, ralf@linux-mips.org, stephen@networkplumber.org, jchapman@katalix.com, jhs@mojatatu.com, bridge@lists.linux-foundation.org, linux-hams@vger.kernel.org, linux-x25@vger.kernel.org, peterz@infradead.org, keescook@chromium.org, linux-rdma@vger.kernel.org, linux-sctp@vger.kernel.org, vyasevich@gmail.com, nhorman@tuxdriver.com, linux-nfs@vger.kernel.org, zyan@redhat.com, sage@redhat.com, bfields@fieldses.org, jlayton@poochiereds.net, steffen.klassert@secunet.com, herbert@gondor.apana.org.au, santosh.shilimkar@oracle.com, jreuter@yaina.de, Elena Reshetova , Hans Liljestrand , David Windsor Subject: [PATCH 07/36] net, atm: convert lec_arp_table.usage from atomic_t to refcount_t Date: Tue, 4 Jul 2017 15:53:02 +0300 Message-Id: <1499172811-16271-8-git-send-email-elena.reshetova@intel.com> In-Reply-To: <1499172811-16271-1-git-send-email-elena.reshetova@intel.com> References: <1499172811-16271-1-git-send-email-elena.reshetova@intel.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: 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 --- net/atm/lec.c | 6 +++--- net/atm/lec_arpc.h | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/net/atm/lec.c b/net/atm/lec.c index 7554571..093fe87 100644 --- a/net/atm/lec.c +++ b/net/atm/lec.c @@ -101,12 +101,12 @@ static void lec_vcc_close(struct lec_priv *priv, struct atm_vcc *vcc); /* must be done under lec_arp_lock */ static inline void lec_arp_hold(struct lec_arp_table *entry) { - atomic_inc(&entry->usage); + refcount_inc(&entry->usage); } static inline void lec_arp_put(struct lec_arp_table *entry) { - if (atomic_dec_and_test(&entry->usage)) + if (refcount_dec_and_test(&entry->usage)) kfree(entry); } @@ -1564,7 +1564,7 @@ static struct lec_arp_table *make_entry(struct lec_priv *priv, to_return->last_used = jiffies; to_return->priv = priv; skb_queue_head_init(&to_return->tx_wait); - atomic_set(&to_return->usage, 1); + refcount_set(&to_return->usage, 1); return to_return; } diff --git a/net/atm/lec_arpc.h b/net/atm/lec_arpc.h index ec67435..d923f53 100644 --- a/net/atm/lec_arpc.h +++ b/net/atm/lec_arpc.h @@ -47,7 +47,7 @@ struct lec_arp_table { * the length of the tlvs array */ struct sk_buff_head tx_wait; /* wait queue for outgoing packets */ - atomic_t usage; /* usage count */ + refcount_t usage; /* usage count */ }; /* -- 2.7.4