From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753027AbdBTKZc (ORCPT ); Mon, 20 Feb 2017 05:25:32 -0500 Received: from mga02.intel.com ([134.134.136.20]:30004 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752988AbdBTKZ3 (ORCPT ); Mon, 20 Feb 2017 05:25:29 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.35,186,1484035200"; d="scan'208";a="935966891" From: Elena Reshetova To: linux-kernel@vger.kernel.org Cc: cgroups@vger.kernel.org, linux-audit@redhat.com, linux-fsdevel@vger.kernel.org, peterz@infradead.org, gregkh@linuxfoundation.org, viro@zeniv.linux.org.uk, tj@kernel.org, mingo@redhat.com, hannes@cmpxchg.org, lizefan@huawei.com, acme@kernel.org, alexander.shishkin@linux.intel.com, paul@paul-moore.com, eparis@redhat.com, akpm@linux-foundation.org, arnd@arndb.de, luto@kernel.org, Elena Reshetova , Hans Liljestrand , Kees Cook , David Windsor Subject: [PATCH 16/19] kernel: convert audit_watch.count from atomic_t to refcount_t Date: Mon, 20 Feb 2017 12:19:05 +0200 Message-Id: <1487585948-6401-17-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1487585948-6401-1-git-send-email-elena.reshetova@intel.com> References: <1487585948-6401-1-git-send-email-elena.reshetova@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- kernel/audit_watch.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index f79e465..8ca9e6c 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -46,7 +46,7 @@ */ struct audit_watch { - atomic_t count; /* reference count */ + refcount_t count; /* reference count */ dev_t dev; /* associated superblock device */ char *path; /* insertion path */ unsigned long ino; /* associated inode number */ @@ -111,12 +111,12 @@ static inline struct audit_parent *audit_find_parent(struct inode *inode) void audit_get_watch(struct audit_watch *watch) { - atomic_inc(&watch->count); + refcount_inc(&watch->count); } void audit_put_watch(struct audit_watch *watch) { - if (atomic_dec_and_test(&watch->count)) { + if (refcount_dec_and_test(&watch->count)) { WARN_ON(watch->parent); WARN_ON(!list_empty(&watch->rules)); kfree(watch->path); @@ -178,7 +178,7 @@ static struct audit_watch *audit_init_watch(char *path) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&watch->rules); - atomic_set(&watch->count, 1); + refcount_set(&watch->count, 1); watch->path = path; watch->dev = AUDIT_DEV_UNSET; watch->ino = AUDIT_INO_UNSET; -- 2.7.4