Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753208AbdGDM51 (ORCPT ); Tue, 4 Jul 2017 08:57:27 -0400 Received: from mga03.intel.com ([134.134.136.65]:10384 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752173AbdGDM5X (ORCPT ); Tue, 4 Jul 2017 08:57:23 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,307,1496127600"; d="scan'208";a="1190388349" 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 25/36] net, x25: convert x25_neigh.refcnt from atomic_t to refcount_t Date: Tue, 4 Jul 2017 15:53:20 +0300 Message-Id: <1499172811-16271-26-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 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-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1703 Lines: 58 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 --- 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 1ac1400..2609b57 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 bcaa180..e0cd04d 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); -- 2.7.4