Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752135AbdGDMym (ORCPT ); Tue, 4 Jul 2017 08:54:42 -0400 Received: from mga05.intel.com ([192.55.52.43]:45549 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752052AbdGDMyi (ORCPT ); Tue, 4 Jul 2017 08:54:38 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,307,1496127600"; d="scan'208";a="1190387573" 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 05/36] net, decnet: convert dn_fib_info.fib_clntref from atomic_t to refcount_t Date: Tue, 4 Jul 2017 15:53:00 +0300 Message-Id: <1499172811-16271-6-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: 2350 Lines: 78 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/dn_fib.h | 5 +++-- net/decnet/dn_fib.c | 6 +++--- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/include/net/dn_fib.h b/include/net/dn_fib.h index f2ca135..81210a8 100644 --- a/include/net/dn_fib.h +++ b/include/net/dn_fib.h @@ -2,6 +2,7 @@ #define _NET_DN_FIB_H #include +#include extern const struct nla_policy rtm_dn_policy[]; @@ -28,7 +29,7 @@ struct dn_fib_info { struct dn_fib_info *fib_next; struct dn_fib_info *fib_prev; int fib_treeref; - atomic_t fib_clntref; + refcount_t fib_clntref; int fib_dead; unsigned int fib_flags; int fib_protocol; @@ -130,7 +131,7 @@ void dn_fib_free_info(struct dn_fib_info *fi); static inline void dn_fib_info_put(struct dn_fib_info *fi) { - if (atomic_dec_and_test(&fi->fib_clntref)) + if (refcount_dec_and_test(&fi->fib_clntref)) dn_fib_free_info(fi); } diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c index f9058eb..f9f6fb3 100644 --- a/net/decnet/dn_fib.c +++ b/net/decnet/dn_fib.c @@ -389,7 +389,7 @@ struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct nlattr *att } fi->fib_treeref++; - atomic_inc(&fi->fib_clntref); + refcount_set(&fi->fib_clntref, 1); spin_lock(&dn_fib_info_lock); fi->fib_next = dn_fib_info_list; fi->fib_prev = NULL; @@ -425,7 +425,7 @@ int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn switch (type) { case RTN_NAT: DN_FIB_RES_RESET(*res); - atomic_inc(&fi->fib_clntref); + refcount_inc(&fi->fib_clntref); return 0; case RTN_UNICAST: case RTN_LOCAL: @@ -438,7 +438,7 @@ int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn } if (nhsel < fi->fib_nhs) { res->nh_sel = nhsel; - atomic_inc(&fi->fib_clntref); + refcount_inc(&fi->fib_clntref); return 0; } endfor_nexthops(fi); -- 2.7.4