From patchwork Fri Jun 18 08:11:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhihao Cheng X-Patchwork-Id: 1494137 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=oBPbO/PS; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4G5ryG02nwz9sSs for ; Fri, 18 Jun 2021 18:03:01 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:CC :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=19rEFdjD2Oz/9KT5f6gQJYP6FTfbt6tdxgNHYIEY22Y=; b=oBPbO/PSw0t273 w1Nv/LhE4EL7u4Jam9UIHS4hNhYJsL1Md8SLBQJ8V4N99VqorNmzLh8oeXBiT/qI+SVZPv5tM5WpU 47ooc1+dVszU2KCHWD/wuM6iKoyjUZYo2xAp6V76obhAJxdEwnfmZ/eoPJ18VrMFxjmlwK7ou0wW/ rEqf+kr4KfsS0JClDdykOVNOk7aR70OBdE8LdSxoH4GNGtK++9+Enu633DVMjwODivA1Ec9nq5WoM HxHIBj9HFeXgOjOmUioOg3q2yu/18i2sAjvAZc1LkPI460n2E2DjKxDm6s7ARKaLXWJpGZrIEXj9r AVU9ubSn0QIkMEplBH4g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lu9SJ-00DDNn-4N; Fri, 18 Jun 2021 08:02:23 +0000 Received: from szxga02-in.huawei.com ([45.249.212.188]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1lu9SC-00DDIl-At for linux-mtd@lists.infradead.org; Fri, 18 Jun 2021 08:02:18 +0000 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4G5rsq6Sf1zZhF0; Fri, 18 Jun 2021 15:59:11 +0800 (CST) Received: from dggema761-chm.china.huawei.com (10.1.198.203) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2176.2; Fri, 18 Jun 2021 16:02:08 +0800 Received: from huawei.com (10.175.127.227) by dggema761-chm.china.huawei.com (10.1.198.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Fri, 18 Jun 2021 16:02:08 +0800 From: Zhihao Cheng To: , CC: , , , Subject: [PATCH] ubifs: Set/Clear I_LINKABLE under i_lock for whiteout inode Date: Fri, 18 Jun 2021 16:11:03 +0800 Message-ID: <20210618081103.3031967-1-chengzhihao1@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggema761-chm.china.huawei.com (10.1.198.203) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210618_010216_639112_23D85F95 X-CRM114-Status: UNSURE ( 6.14 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -2.3 (--) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: xfstests-generic/476 reports a warning message as below: WARNING: CPU: 2 PID: 30347 at fs/inode.c:361 inc_nlink+0x52/0x70 Call Trace: do_rename+0x502/0xd40 [ubifs] ubifs_rename+0x8b/0x180 [ubifs] vfs_rename+0x476/0x1080 do_renameat2+0x67c/0x7b0 __x64_sys_re [...] Content analysis details: (-2.3 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [45.249.212.188 listed in list.dnswl.org] 0.0 RCVD_IN_MSPIKE_H4 RBL: Very Good reputation (+4) [45.249.212.188 listed in wl.mailspike.net] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.0 RCVD_IN_MSPIKE_WL Mailspike good senders X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org xfstests-generic/476 reports a warning message as below: WARNING: CPU: 2 PID: 30347 at fs/inode.c:361 inc_nlink+0x52/0x70 Call Trace: do_rename+0x502/0xd40 [ubifs] ubifs_rename+0x8b/0x180 [ubifs] vfs_rename+0x476/0x1080 do_renameat2+0x67c/0x7b0 __x64_sys_renameat2+0x6e/0x90 do_syscall_64+0x66/0xe0 entry_SYSCALL_64_after_hwframe+0x44/0xae Following race case can cause this: rename_whiteout(Thread 1) wb_workfn(Thread 2) ubifs_rename do_rename __writeback_single_inode spin_lock(&inode->i_lock) whiteout->i_state |= I_LINKABLE inode->i_state &= ~dirty; ---- How race happens on i_state: (tmp = whiteout->i_state | I_LINKABLE) (tmp = inode->i_state & ~dirty) (whiteout->i_state = tmp) (inode->i_state = tmp) ---- spin_unlock(&inode->i_lock) inc_nlink(whiteout) WARN_ON(!(inode->i_state & I_LINKABLE)) !!! Fix to add i_lock to avoid i_state update race condition. Fixes: 9e0a1fff8db56ea ("ubifs: Implement RENAME_WHITEOUT") Signed-off-by: Zhihao Cheng --- fs/ubifs/dir.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 5bd8482e660a..7c61d0ec0159 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -1337,7 +1337,10 @@ static int do_rename(struct inode *old_dir, struct dentry *old_dentry, goto out_release; } + spin_lock(&whiteout->i_lock); whiteout->i_state |= I_LINKABLE; + spin_unlock(&whiteout->i_lock); + whiteout_ui = ubifs_inode(whiteout); whiteout_ui->data = dev; whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0)); @@ -1430,7 +1433,11 @@ static int do_rename(struct inode *old_dir, struct dentry *old_dentry, inc_nlink(whiteout); mark_inode_dirty(whiteout); + + spin_lock(&whiteout->i_lock); whiteout->i_state &= ~I_LINKABLE; + spin_unlock(&whiteout->i_lock); + iput(whiteout); }