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 A21B5C43334 for ; Mon, 18 Jul 2022 11:23:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233750AbiGRLX5 (ORCPT ); Mon, 18 Jul 2022 07:23:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233294AbiGRLXz (ORCPT ); Mon, 18 Jul 2022 07:23:55 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 743442DE5 for ; Mon, 18 Jul 2022 04:23:53 -0700 (PDT) Received: from canpemm500010.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4LmffY5sjVz1M7wX; Mon, 18 Jul 2022 19:21:09 +0800 (CST) Received: from huawei.com (10.175.127.227) by canpemm500010.china.huawei.com (7.192.105.118) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 18 Jul 2022 19:23:50 +0800 From: Ye Bin To: , CC: , , Ye Bin Subject: [PATCH -next RFC] f2fs: fix null-ptr-deref in f2fs_get_dnode_of_data Date: Mon, 18 Jul 2022 19:36:09 +0800 Message-ID: <20220718113609.154371-1-yebin10@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To canpemm500010.china.huawei.com (7.192.105.118) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is issue as follows when test f2fs atomic write: F2FS-fs (loop0): Can't find valid F2FS filesystem in 2th superblock F2FS-fs (loop0): invalid crc_offset: 0 F2FS-fs (loop0): f2fs_check_nid_range: out-of-range nid=1, run fsck to fix. F2FS-fs (loop0): f2fs_check_nid_range: out-of-range nid=2, run fsck to fix. ================================================================== BUG: KASAN: null-ptr-deref in f2fs_get_dnode_of_data+0xac/0x16d0 Read of size 8 at addr 0000000000000028 by task rep/1990 CPU: 4 PID: 1990 Comm: rep Not tainted 5.19.0-rc6-next-20220715 #266 Call Trace: dump_stack_lvl+0x6e/0x91 print_report.cold+0x49a/0x6bb kasan_report+0xa8/0x130 f2fs_get_dnode_of_data+0xac/0x16d0 f2fs_do_write_data_page+0x2a5/0x1030 move_data_page+0x3c5/0xdf0 do_garbage_collect+0x2015/0x36c0 f2fs_gc+0x554/0x1d30 f2fs_balance_fs+0x7f5/0xda0 f2fs_write_single_data_page+0xb66/0xdc0 f2fs_write_cache_pages+0x716/0x1420 f2fs_write_data_pages+0x84f/0x9a0 do_writepages+0x130/0x3a0 filemap_fdatawrite_wbc+0x87/0xa0 file_write_and_wait_range+0x157/0x1c0 f2fs_do_sync_file+0x206/0x12d0 f2fs_sync_file+0x99/0xc0 vfs_fsync_range+0x75/0x140 f2fs_file_write_iter+0xd7b/0x1850 vfs_write+0x645/0x780 ksys_write+0xf1/0x1e0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd As 3db1de0e582c commit changed atomic write way which new a cow_inode for atomic write file, and also mark cow_inode as FI_ATOMIC_FILE. When f2fs_do_write_data_page write cow_inode will use cow_inode's cow_inode which is NULL. Then will trigger null-ptr-deref. To solve above issue, don't mark cow_inode as FI_ATOMIC_FILE. Fiexes: 3db1de0e582c("f2fs: change the current atomic write way") Signed-off-by: Ye Bin --- fs/f2fs/file.c | 1 - 1 file changed, 1 deletion(-) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 466eb00aa516..735802b6b754 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -2062,7 +2062,6 @@ static int f2fs_ioc_start_atomic_write(struct file *filp) spin_unlock(&sbi->inode_lock[ATOMIC_FILE]); set_inode_flag(inode, FI_ATOMIC_FILE); - set_inode_flag(fi->cow_inode, FI_ATOMIC_FILE); clear_inode_flag(fi->cow_inode, FI_INLINE_DATA); f2fs_up_write(&fi->i_gc_rwsem[WRITE]); -- 2.31.1