From patchwork Tue Mar 14 07:07:14 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Reshetova, Elena" X-Patchwork-Id: 9622597 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 0D1F560244 for ; Tue, 14 Mar 2017 07:10:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EFF1C284EF for ; Tue, 14 Mar 2017 07:10:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E4EC2284F8; Tue, 14 Mar 2017 07:10:11 +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=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=unavailable 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 96ACC284EF for ; Tue, 14 Mar 2017 07:10:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751145AbdCNHKA (ORCPT ); Tue, 14 Mar 2017 03:10:00 -0400 Received: from mga11.intel.com ([192.55.52.93]:9169 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751072AbdCNHHs (ORCPT ); Tue, 14 Mar 2017 03:07:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=intel.com; i=@intel.com; q=dns/txt; s=intel; t=1489475267; x=1521011267; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=/XnPrE/9zbkwLwuxPFvpBSQMrU/gqbyTk1ekl6LAhO0=; b=Dmb488dGNVH4OPlhlKyIqAmoLKPPn6d2Zh0LAdh42Xiq8yFaOSLq+PlO 0kkt8eD1ADTjvCBJW71F7t4sfm4FFw==; Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Mar 2017 00:07:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,162,1486454400"; d="scan'208";a="944018249" Received: from elena-thinkpad-x230.fi.intel.com ([10.237.72.51]) by orsmga003.jf.intel.com with ESMTP; 14 Mar 2017 00:07:39 -0700 From: Elena Reshetova To: trond.myklebust@primarydata.com Cc: linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, anna.schumaker@netapp.com, peterz@infradead.org, keescook@chromium.org, Elena Reshetova , Hans Liljestrand , David Windsor Subject: [PATCH 06/12] fs, nfs: convert pnfs_layout_hdr.plh_refcount from atomic_t to refcount_t Date: Tue, 14 Mar 2017 09:07:14 +0200 Message-Id: <1489475240-6594-7-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1489475240-6594-1-git-send-email-elena.reshetova@intel.com> References: <1489475240-6594-1-git-send-email-elena.reshetova@intel.com> Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@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/nfs/pnfs.c | 12 ++++++------ fs/nfs/pnfs.h | 2 +- 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 155781c..7d39d96 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -251,7 +251,7 @@ EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver); void pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo) { - atomic_inc(&lo->plh_refcount); + refcount_inc(&lo->plh_refcount); } static struct pnfs_layout_hdr * @@ -296,7 +296,7 @@ pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo) pnfs_layoutreturn_before_put_layout_hdr(lo); - if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) { + if (refcount_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) { if (!list_empty(&lo->plh_segs)) WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n"); pnfs_detach_layout_hdr(lo); @@ -389,14 +389,14 @@ pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit) { lo->plh_retry_timestamp = jiffies; if (!test_and_set_bit(fail_bit, &lo->plh_flags)) - atomic_inc(&lo->plh_refcount); + refcount_inc(&lo->plh_refcount); } static void pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit) { if (test_and_clear_bit(fail_bit, &lo->plh_flags)) - atomic_dec(&lo->plh_refcount); + refcount_dec(&lo->plh_refcount); } static void @@ -466,7 +466,7 @@ pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo, WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags)); list_del_init(&lseg->pls_list); /* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */ - atomic_dec(&lo->plh_refcount); + refcount_dec(&lo->plh_refcount); if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)) return; if (list_empty(&lo->plh_segs) && @@ -1487,7 +1487,7 @@ alloc_init_layout_hdr(struct inode *ino, lo = pnfs_alloc_layout_hdr(ino, gfp_flags); if (!lo) return NULL; - atomic_set(&lo->plh_refcount, 1); + refcount_set(&lo->plh_refcount, 1); INIT_LIST_HEAD(&lo->plh_layouts); INIT_LIST_HEAD(&lo->plh_segs); INIT_LIST_HEAD(&lo->plh_return_segs); diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h index 75698fa..61cafea 100644 --- a/fs/nfs/pnfs.h +++ b/fs/nfs/pnfs.h @@ -186,7 +186,7 @@ struct pnfs_layoutdriver_type { }; struct pnfs_layout_hdr { - atomic_t plh_refcount; + refcount_t plh_refcount; atomic_t plh_outstanding; /* number of RPCs out */ struct list_head plh_layouts; /* other client layouts */ struct list_head plh_bulk_destroy;