Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752969AbdGDM4N (ORCPT ); Tue, 4 Jul 2017 08:56:13 -0400 Received: from mga07.intel.com ([134.134.136.100]:4768 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752559AbdGDM4K (ORCPT ); Tue, 4 Jul 2017 08:56:10 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,307,1496127600"; d="scan'208";a="1190388034" 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 16/36] net, netrom: convert nr_neigh.refcount from atomic_t to refcount_t Date: Tue, 4 Jul 2017 15:53:11 +0300 Message-Id: <1499172811-16271-17-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: 2409 Lines: 74 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/netrom.h | 7 ++++--- net/netrom/nr_route.c | 4 ++-- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/include/net/netrom.h b/include/net/netrom.h index 110350a..cecb4fd 100644 --- a/include/net/netrom.h +++ b/include/net/netrom.h @@ -11,6 +11,7 @@ #include #include #include +#include #define NR_NETWORK_LEN 15 #define NR_TRANSPORT_LEN 5 @@ -93,7 +94,7 @@ struct nr_neigh { unsigned short count; unsigned int number; unsigned char failed; - atomic_t refcount; + refcount_t refcount; }; struct nr_route { @@ -128,11 +129,11 @@ static __inline__ void nr_node_put(struct nr_node *nr_node) } #define nr_neigh_hold(__nr_neigh) \ - atomic_inc(&((__nr_neigh)->refcount)) + refcount_inc(&((__nr_neigh)->refcount)) static __inline__ void nr_neigh_put(struct nr_neigh *nr_neigh) { - if (atomic_dec_and_test(&nr_neigh->refcount)) { + if (refcount_dec_and_test(&nr_neigh->refcount)) { if (nr_neigh->ax25) ax25_cb_put(nr_neigh->ax25); kfree(nr_neigh->digipeat); diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c index d72a4f1..6b72970 100644 --- a/net/netrom/nr_route.c +++ b/net/netrom/nr_route.c @@ -149,7 +149,7 @@ static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic, nr_neigh->count = 0; nr_neigh->number = nr_neigh_no++; nr_neigh->failed = 0; - atomic_set(&nr_neigh->refcount, 1); + refcount_set(&nr_neigh->refcount, 1); if (ax25_digi != NULL && ax25_digi->ndigi > 0) { nr_neigh->digipeat = kmemdup(ax25_digi, @@ -431,7 +431,7 @@ static int __must_check nr_add_neigh(ax25_address *callsign, nr_neigh->count = 0; nr_neigh->number = nr_neigh_no++; nr_neigh->failed = 0; - atomic_set(&nr_neigh->refcount, 1); + refcount_set(&nr_neigh->refcount, 1); if (ax25_digi != NULL && ax25_digi->ndigi > 0) { nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi), -- 2.7.4