Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753417AbdGDM7B (ORCPT ); Tue, 4 Jul 2017 08:59:01 -0400 Received: from mga11.intel.com ([192.55.52.93]:17674 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751852AbdGDM6z (ORCPT ); Tue, 4 Jul 2017 08:58:55 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,307,1496127600"; d="scan'208";a="1190388634" 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 34/36] net, ax25: convert ax25_uid_assoc.refcount from atomic_t to refcount_t Date: Tue, 4 Jul 2017 15:53:29 +0300 Message-Id: <1499172811-16271-35-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: 1931 Lines: 66 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/ax25.h | 8 ++++---- net/ax25/ax25_uid.c | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/include/net/ax25.h b/include/net/ax25.h index e602f81..edd82f0 100644 --- a/include/net/ax25.h +++ b/include/net/ax25.h @@ -11,7 +11,7 @@ #include #include #include -#include +#include #include #include @@ -158,7 +158,7 @@ enum { typedef struct ax25_uid_assoc { struct hlist_node uid_node; - atomic_t refcount; + refcount_t refcount; kuid_t uid; ax25_address call; } ax25_uid_assoc; @@ -167,11 +167,11 @@ typedef struct ax25_uid_assoc { hlist_for_each_entry(__ax25, list, uid_node) #define ax25_uid_hold(ax25) \ - atomic_inc(&((ax25)->refcount)) + refcount_inc(&((ax25)->refcount)) static inline void ax25_uid_put(ax25_uid_assoc *assoc) { - if (atomic_dec_and_test(&assoc->refcount)) { + if (refcount_dec_and_test(&assoc->refcount)) { kfree(assoc); } } diff --git a/net/ax25/ax25_uid.c b/net/ax25/ax25_uid.c index 0403b0d..83b035f 100644 --- a/net/ax25/ax25_uid.c +++ b/net/ax25/ax25_uid.c @@ -107,7 +107,7 @@ int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax) if ((ax25_uid = kmalloc(sizeof(*ax25_uid), GFP_KERNEL)) == NULL) return -ENOMEM; - atomic_set(&ax25_uid->refcount, 1); + refcount_set(&ax25_uid->refcount, 1); ax25_uid->uid = sax25_kuid; ax25_uid->call = sax->sax25_call; -- 2.7.4