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 8A833C352AA for ; Tue, 5 Apr 2022 11:47:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381647AbiDELqs (ORCPT ); Tue, 5 Apr 2022 07:46:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48494 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354756AbiDEKPd (ORCPT ); Tue, 5 Apr 2022 06:15:33 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D3A36C4A5; Tue, 5 Apr 2022 03:02:36 -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 dfw.source.kernel.org (Postfix) with ESMTPS id BE4E161740; Tue, 5 Apr 2022 10:02:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C5E64C385A1; Tue, 5 Apr 2022 10:02:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649152955; bh=locgQxsyc0MpvAdZeZH1B7amSJ1o7txFD/CTHTitM/g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JkaBythOPpsAqlnM1UmkT7GPGCubDuz0L2jj5NP97f1xYymLODM6pqSeHblqidvGh AAoq35pmx1535L62sEVigAp0dVvWiTTcvv4mrmzX8dSD4sJahLBCz2Z8G1ukpGJHlV iAXo2peRT/GWXjRsoznlcHDN23G9BuhJQmehFsNE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chao Yu , Jaegeuk Kim Subject: [PATCH 5.10 050/599] f2fs: fix to do sanity check on .cp_pack_total_block_count Date: Tue, 5 Apr 2022 09:25:44 +0200 Message-Id: <20220405070300.317859746@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070258.802373272@linuxfoundation.org> References: <20220405070258.802373272@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Chao Yu commit 5b5b4f85b01604389f7a0f11ef180a725bf0e2d4 upstream. As bughunter reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215709 f2fs may hang when mounting a fuzzed image, the dmesg shows as below: __filemap_get_folio+0x3a9/0x590 pagecache_get_page+0x18/0x60 __get_meta_page+0x95/0x460 [f2fs] get_checkpoint_version+0x2a/0x1e0 [f2fs] validate_checkpoint+0x8e/0x2a0 [f2fs] f2fs_get_valid_checkpoint+0xd0/0x620 [f2fs] f2fs_fill_super+0xc01/0x1d40 [f2fs] mount_bdev+0x18a/0x1c0 f2fs_mount+0x15/0x20 [f2fs] legacy_get_tree+0x28/0x50 vfs_get_tree+0x27/0xc0 path_mount+0x480/0xaa0 do_mount+0x7c/0xa0 __x64_sys_mount+0x8b/0xe0 do_syscall_64+0x38/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae The root cause is cp_pack_total_block_count field in checkpoint was fuzzed to one, as calcuated, two cp pack block locates in the same block address, so then read latter cp pack block, it will block on the page lock due to the lock has already held when reading previous cp pack block, fix it by adding sanity check for cp_pack_total_block_count. Cc: stable@vger.kernel.org Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman --- fs/f2fs/checkpoint.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -851,6 +851,7 @@ static struct page *validate_checkpoint( struct page *cp_page_1 = NULL, *cp_page_2 = NULL; struct f2fs_checkpoint *cp_block = NULL; unsigned long long cur_version = 0, pre_version = 0; + unsigned int cp_blocks; int err; err = get_checkpoint_version(sbi, cp_addr, &cp_block, @@ -858,15 +859,16 @@ static struct page *validate_checkpoint( if (err) return NULL; - if (le32_to_cpu(cp_block->cp_pack_total_block_count) > - sbi->blocks_per_seg) { + cp_blocks = le32_to_cpu(cp_block->cp_pack_total_block_count); + + if (cp_blocks > sbi->blocks_per_seg || cp_blocks <= F2FS_CP_PACKS) { f2fs_warn(sbi, "invalid cp_pack_total_block_count:%u", le32_to_cpu(cp_block->cp_pack_total_block_count)); goto invalid_cp; } pre_version = *version; - cp_addr += le32_to_cpu(cp_block->cp_pack_total_block_count) - 1; + cp_addr += cp_blocks - 1; err = get_checkpoint_version(sbi, cp_addr, &cp_block, &cp_page_2, version); if (err)