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 C524EC25B0C for ; Mon, 8 Aug 2022 01:33:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242130AbiHHBdW (ORCPT ); Sun, 7 Aug 2022 21:33:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57892 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242126AbiHHBcp (ORCPT ); Sun, 7 Aug 2022 21:32:45 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2F0ECE08; Sun, 7 Aug 2022 18:32:25 -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 1D060B80DC0; Mon, 8 Aug 2022 01:32:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0ED1EC433C1; Mon, 8 Aug 2022 01:32:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1659922342; bh=Ll3VrOpxsVmeadqheby9L6HRHAFePhaWMYtkUoqpQtY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T/+xKW8foK/5W1nr9jPRLOlhEHRHv1Z/jZabrfga+FDoDdkIa3BH+Wy5L2SDjpMoy 8Ay5cAYZ1eCK6LR0bpYh922qnJXQWhd7PF586SJZC7lwzkMituCvn9uOgzOT/3gNnB ACPRBlRBY+5Dy6ibFF/TmcpF+OJPjwODnYPw1llRTM/Gdc/Z3kDyo0RH9ZiPWiVDyJ Je8Uj81+X5NO7ZQOCmdJ43HxK71nfmBisq7/tuLL+37nMsNtWKpjlYiTDVYOG9NQLX J8/JQsRqOG6zQshzAVceqqXmstBqlRf0EPD19gzKP/uXHpIdctAZ5/PeXs6HbrwGQj CcWiMCIjREnuQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jan Kara , syzbot+d273f7d7f58afd93be48@syzkaller.appspotmail.com, Sasha Levin , jack@suse.com, linux-ext4@vger.kernel.org Subject: [PATCH AUTOSEL 5.19 15/58] ext2: Add more validity checks for inode counts Date: Sun, 7 Aug 2022 21:30:33 -0400 Message-Id: <20220808013118.313965-15-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220808013118.313965-1-sashal@kernel.org> References: <20220808013118.313965-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org From: Jan Kara [ Upstream commit fa78f336937240d1bc598db817d638086060e7e9 ] Add checks verifying number of inodes stored in the superblock matches the number computed from number of inodes per group. Also verify we have at least one block worth of inodes per group. This prevents crashes on corrupted filesystems. Reported-by: syzbot+d273f7d7f58afd93be48@syzkaller.appspotmail.com Signed-off-by: Jan Kara Signed-off-by: Sasha Levin --- fs/ext2/super.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/ext2/super.c b/fs/ext2/super.c index f6a19f6d9f6d..cdffa2a041af 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -1059,9 +1059,10 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) sbi->s_frags_per_group); goto failed_mount; } - if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { + if (sbi->s_inodes_per_group < sbi->s_inodes_per_block || + sbi->s_inodes_per_group > sb->s_blocksize * 8) { ext2_msg(sb, KERN_ERR, - "error: #inodes per group too big: %lu", + "error: invalid #inodes per group: %lu", sbi->s_inodes_per_group); goto failed_mount; } @@ -1071,6 +1072,13 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - le32_to_cpu(es->s_first_data_block) - 1) / EXT2_BLOCKS_PER_GROUP(sb)) + 1; + if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group != + le32_to_cpu(es->s_inodes_count)) { + ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu", + le32_to_cpu(es->s_inodes_count), + (u64)sbi->s_groups_count * sbi->s_inodes_per_group); + goto failed_mount; + } db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / EXT2_DESC_PER_BLOCK(sb); sbi->s_group_desc = kmalloc_array(db_count, -- 2.35.1