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 X-Spam-Level: X-Spam-Status: No, score=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8135C433E9 for ; Wed, 30 Dec 2020 13:06:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C5546221FA for ; Wed, 30 Dec 2020 13:06:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726875AbgL3NGO (ORCPT ); Wed, 30 Dec 2020 08:06:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:54532 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727555AbgL3NFm (ORCPT ); Wed, 30 Dec 2020 08:05:42 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8ACFE22B2A; Wed, 30 Dec 2020 13:04:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1609333497; bh=ZSE84jnmNAMRoX0/d4aYJMeoZmF9nUQ9vl3HVCoqB38=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V8ryd7uwI2SAFl9vfFEDJYeBA9BnZGdtfPesKdwSy7j/5wAHsQ6qw6M4CrSO0mSz5 03LxbUheLkc9nFZ4esQpNFnRg1IGjdDbejab6srAx+kZ2aGChtOnOPuQQT445pc0L4 M5CYJSDTza7x2PRFoQZZ6RF7O09vCtUdtA0dqavPGYE7G3REK3MF4aDYmdJgkTZ7D1 qURv8LOp/JYESjXvx4GgJjoTtQsPbzh/lBE6d79dhrrpXuioHwEMC7JDyQ/IsOVfjy L1vcj0t39Qe/Ay8s9pGJmMq2BP+Uf/EO4uq4xOxLLfGSAaV3djxIFYgi9wMm7XumN0 dMoLQliyYhEAQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jan Kara , Andreas Dilger , Sasha Levin Subject: [PATCH AUTOSEL 4.4 2/5] quota: Don't overflow quota file offsets Date: Wed, 30 Dec 2020 08:04:51 -0500 Message-Id: <20201230130454.3637785-2-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201230130454.3637785-1-sashal@kernel.org> References: <20201230130454.3637785-1-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-kernel@vger.kernel.org From: Jan Kara [ Upstream commit 10f04d40a9fa29785206c619f80d8beedb778837 ] The on-disk quota format supports quota files with upto 2^32 blocks. Be careful when computing quota file offsets in the quota files from block numbers as they can overflow 32-bit types. Since quota files larger than 4GB would require ~26 millions of quota users, this is mostly a theoretical concern now but better be careful, fuzzers would find the problem sooner or later anyway... Reviewed-by: Andreas Dilger Signed-off-by: Jan Kara Signed-off-by: Sasha Levin --- fs/quota/quota_tree.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/quota/quota_tree.c b/fs/quota/quota_tree.c index 58efb83dec1c8..3069b11867194 100644 --- a/fs/quota/quota_tree.c +++ b/fs/quota/quota_tree.c @@ -55,7 +55,7 @@ static ssize_t read_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf) memset(buf, 0, info->dqi_usable_bs); return sb->s_op->quota_read(sb, info->dqi_type, buf, - info->dqi_usable_bs, blk << info->dqi_blocksize_bits); + info->dqi_usable_bs, (loff_t)blk << info->dqi_blocksize_bits); } static ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf) @@ -64,7 +64,7 @@ static ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf) ssize_t ret; ret = sb->s_op->quota_write(sb, info->dqi_type, buf, - info->dqi_usable_bs, blk << info->dqi_blocksize_bits); + info->dqi_usable_bs, (loff_t)blk << info->dqi_blocksize_bits); if (ret != info->dqi_usable_bs) { quota_error(sb, "dquota write failed"); if (ret >= 0) @@ -277,7 +277,7 @@ static uint find_free_dqentry(struct qtree_mem_dqinfo *info, blk); goto out_buf; } - dquot->dq_off = (blk << info->dqi_blocksize_bits) + + dquot->dq_off = ((loff_t)blk << info->dqi_blocksize_bits) + sizeof(struct qt_disk_dqdbheader) + i * info->dqi_entry_size; kfree(buf); @@ -552,7 +552,7 @@ static loff_t find_block_dqentry(struct qtree_mem_dqinfo *info, ret = -EIO; goto out_buf; } else { - ret = (blk << info->dqi_blocksize_bits) + sizeof(struct + ret = ((loff_t)blk << info->dqi_blocksize_bits) + sizeof(struct qt_disk_dqdbheader) + i * info->dqi_entry_size; } out_buf: -- 2.27.0