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 96E05C25B07 for ; Mon, 8 Aug 2022 01:57:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243683AbiHHB5U (ORCPT ); Sun, 7 Aug 2022 21:57:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46050 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243756AbiHHBz4 (ORCPT ); Sun, 7 Aug 2022 21:55:56 -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 C7DA41C12C; Sun, 7 Aug 2022 18:39:23 -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 C54DE60EA5; Mon, 8 Aug 2022 01:39:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53C0FC43470; Mon, 8 Aug 2022 01:39:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1659922762; bh=2VWKfxtQ5ExyRo+X1gZyywgtIu3OQS7nZSsQWwD9TLw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=llsIFlDzhDImSYEXuygCI8w587gmkpMILAl4WnGbKCpNSMw8+5aE9U5JZTI+SDPIK 9jR5Fv358VuLwCO86k5+XbxJbOnz64WsHl4zzVq70GUAaggyr8WWFAZQUf91gsZCHB MmlmCmcS+D5p2ThIFpHf3M4AKQ6ysk640wmX2MElkGOo9JMJI3oST3ald+BEW8FgEJ yR1Pmadwh6h2Nk+Q+TAlJMSTjwHJlACnJl7pv6BrMxrq5fRMcSlL0HBVCtwNWN2Cui M2jYX+usvX+uuTH/kmjw5sx5FWFXzs/UMqtg3OZ8GoxePRti3/Hg1CHfyq76O7EhQd kNCi9FxMuJHqw== 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 4.19 03/16] ext2: Add more validity checks for inode counts Date: Sun, 7 Aug 2022 21:39:00 -0400 Message-Id: <20220808013914.316709-3-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220808013914.316709-1-sashal@kernel.org> References: <20220808013914.316709-1-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 ad9fd08f66ba..44a1f356aca2 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -1088,9 +1088,10 @@ 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; } @@ -1100,6 +1101,13 @@ 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