From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C307CC433F5 for ; Mon, 28 Mar 2022 16:03:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240836AbiC1QEv (ORCPT ); Mon, 28 Mar 2022 12:04:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240807AbiC1QEt (ORCPT ); Mon, 28 Mar 2022 12:04:49 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21EF85DE50 for ; Mon, 28 Mar 2022 09:03:08 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id D934BB810D5 for ; Mon, 28 Mar 2022 16:03:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F74BC004DD; Mon, 28 Mar 2022 16:03:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1648483385; bh=P0P3Lnt4gmVt++k6Xk8i+eUeKJePtopQkH5guyzaals=; h=From:To:Cc:Subject:Date:From; b=oEzW3aC2jtw45GDsyEznM0jFg8h+Yzbq/A+p0lUe6s0UE/V+mpj8F1WgbxJpOC1T/ yPgto4nsBiPimjOwwvze5QLkxulYoqi3uh7+YyIGHf/Em/ACHGvYfjrhw5FM3z9pNt CdbLyYP3WOvSLPfWzJF++nW79ZiQClnPj1D3yFuNE3QLDx29iUO6EdDNGkLfxDWWQ8 TPJl/vI91vEINeKuW7cDofEkBBUhxPqyvQomUur8LciuSTtpnGPhcygAf1cYNpZTuh qRrAel1D7zGYsEMNIZZoKiAZjnkr4YEfXbxmXpJDLTlZ6OXDt74jeS8Kspx82WcLn4 g+ERzIdLrxWew== From: Chao Yu To: jaegeuk@kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Chao Yu , Wenqing Liu , Chao Yu Subject: [PATCH] f2fs: fix to do sanity check on inline_dots inode Date: Tue, 29 Mar 2022 00:02:53 +0800 Message-Id: <20220328160253.3102-1-chao@kernel.org> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As Wenqing reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215765 It will cause a kernel panic with steps: - mkdir mnt - mount tmp40.img mnt - ls mnt folio_mark_dirty+0x33/0x50 f2fs_add_regular_entry+0x541/0xad0 [f2fs] f2fs_add_dentry+0x6c/0xb0 [f2fs] f2fs_do_add_link+0x182/0x230 [f2fs] __recover_dot_dentries+0x2d6/0x470 [f2fs] f2fs_lookup+0x5af/0x6a0 [f2fs] __lookup_slow+0xac/0x200 lookup_slow+0x45/0x70 walk_component+0x16c/0x250 path_lookupat+0x8b/0x1f0 filename_lookup+0xef/0x250 user_path_at_empty+0x46/0x70 vfs_statx+0x98/0x190 __do_sys_newlstat+0x41/0x90 __x64_sys_newlstat+0x1a/0x30 do_syscall_64+0x37/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae The root cause is for special file: e.g. character, block, fifo or socket file, f2fs doesn't assign address space operations pointer array for mapping->a_ops field, so, in a fuzzed image, if inline_dots flag was tagged in special file, during lookup(), when f2fs runs into __recover_dot_dentries(), it will cause NULL pointer access once f2fs_add_regular_entry() calls a_ops->set_dirty_page(). Fixes: 510022a85839 ("f2fs: add F2FS_INLINE_DOTS to recover missing dot dentries") Reported-by: Wenqing Liu Signed-off-by: Chao Yu --- fs/f2fs/namei.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index 906e9e301ac8..e3f23ae9bb19 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -461,6 +461,13 @@ static int __recover_dot_dentries(struct inode *dir, nid_t pino) return 0; } + if (!S_ISDIR(dir->i_mode)) { + f2fs_err(sbi, "inconsistent inode status, skip recovering inline_dots inode (ino:%lu, i_mode:%u, pino:%u)", + dir->i_ino, dir->i_mode, pino); + set_sbi_flag(sbi, SBI_NEED_FSCK); + return -ENOTDIR; + } + err = f2fs_dquot_initialize(dir); if (err) return err; -- 2.32.0