From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751821AbdCHI7W (ORCPT ); Wed, 8 Mar 2017 03:59:22 -0500 Received: from mga07.intel.com ([134.134.136.100]:32163 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751840AbdCHI7V (ORCPT ); Wed, 8 Mar 2017 03:59:21 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,262,1486454400"; d="scan'208";a="1139427415" From: Elena Reshetova To: darrick.wong@oracle.com Cc: linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, Elena Reshetova , Hans Liljestrand , Kees Cook , David Windsor Subject: [PATCH 5/5] fs, xfs: convert xfs_rui_log_item.rui_refcount from atomic_t to refcount_t Date: Wed, 8 Mar 2017 10:53:39 +0200 Message-Id: <1488963219-11709-6-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1488963219-11709-1-git-send-email-elena.reshetova@intel.com> References: <1488963219-11709-1-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 --- fs/xfs/xfs_rmap_item.c | 4 ++-- fs/xfs/xfs_rmap_item.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c index 73c8278..5e1664a 100644 --- a/fs/xfs/xfs_rmap_item.c +++ b/fs/xfs/xfs_rmap_item.c @@ -204,7 +204,7 @@ xfs_rui_init( ruip->rui_format.rui_nextents = nextents; ruip->rui_format.rui_id = (uintptr_t)(void *)ruip; atomic_set(&ruip->rui_next_extent, 0); - atomic_set(&ruip->rui_refcount, 2); + refcount_set(&ruip->rui_refcount, 2); return ruip; } @@ -243,7 +243,7 @@ void xfs_rui_release( struct xfs_rui_log_item *ruip) { - if (atomic_dec_and_test(&ruip->rui_refcount)) { + if (refcount_dec_and_test(&ruip->rui_refcount)) { xfs_trans_ail_remove(&ruip->rui_item, SHUTDOWN_LOG_IO_ERROR); xfs_rui_item_free(ruip); } diff --git a/fs/xfs/xfs_rmap_item.h b/fs/xfs/xfs_rmap_item.h index 340c968..1e425a9 100644 --- a/fs/xfs/xfs_rmap_item.h +++ b/fs/xfs/xfs_rmap_item.h @@ -64,7 +64,7 @@ struct kmem_zone; */ struct xfs_rui_log_item { struct xfs_log_item rui_item; - atomic_t rui_refcount; + refcount_t rui_refcount; atomic_t rui_next_extent; unsigned long rui_flags; /* misc flags */ struct xfs_rui_log_format rui_format; -- 2.7.4