From patchwork Tue Feb 21 15:49:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Reshetova, Elena" X-Patchwork-Id: 9584915 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1A47960578 for ; Tue, 21 Feb 2017 15:49:44 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 067F72003F for ; Tue, 21 Feb 2017 15:49:44 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EF608288F2; Tue, 21 Feb 2017 15:49:43 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9F143223A6 for ; Tue, 21 Feb 2017 15:49:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752374AbdBUPtm (ORCPT ); Tue, 21 Feb 2017 10:49:42 -0500 Received: from mga02.intel.com ([134.134.136.20]:6976 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752777AbdBUPtk (ORCPT ); Tue, 21 Feb 2017 10:49:40 -0500 Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Feb 2017 07:49:33 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.35,190,1484035200"; d="scan'208";a="67318744" Received: from michalrx-mobl.ger.corp.intel.com (HELO elena-ThinkPad-X230.ger.corp.intel.com) ([10.249.39.9]) by orsmga005.jf.intel.com with ESMTP; 21 Feb 2017 07:49:30 -0800 From: Elena Reshetova To: linux-kernel@vger.kernel.org Cc: linux-xfs@vger.kernel.org, peterz@infradead.org, gregkh@linuxfoundation.org, darrick.wong@oracle.com, Elena Reshetova , Hans Liljestrand , Kees Cook , David Windsor Subject: [PATCH 7/7] fs, xfs: convert xfs_rui_log_item.rui_refcount from atomic_t to refcount_t Date: Tue, 21 Feb 2017 17:49:07 +0200 Message-Id: <1487692147-17066-8-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1487692147-17066-1-git-send-email-elena.reshetova@intel.com> References: <1487692147-17066-1-git-send-email-elena.reshetova@intel.com> Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 | 4 +++- 2 files changed, 5 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..2529a35 100644 --- a/fs/xfs/xfs_rmap_item.h +++ b/fs/xfs/xfs_rmap_item.h @@ -20,6 +20,8 @@ #ifndef __XFS_RMAP_ITEM_H__ #define __XFS_RMAP_ITEM_H__ +#include + /* * There are (currently) three pairs of rmap btree redo item types: map, unmap, * and convert. The common abbreviations for these are RUI (rmap update @@ -64,7 +66,7 @@ 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;