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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 BEE08C43333 for ; Wed, 23 Dec 2020 15:34:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A84B02158C for ; Wed, 23 Dec 2020 15:34:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729092AbgLWPe5 (ORCPT ); Wed, 23 Dec 2020 10:34:57 -0500 Received: from mail.kernel.org ([198.145.29.99]:46350 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729020AbgLWPev (ORCPT ); Wed, 23 Dec 2020 10:34:51 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2A2AD23357; Wed, 23 Dec 2020 15:33:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1608737638; bh=aGC0JfFCEIt7cjYdcfYSxj1bmNL0C97XIs09NRvgTDQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=egYoI+vmWu3uQulSuDUm9J73dTv06BMzOG/yF9MZxAwq8ZhrAql9XmSFY57x8oEoZ Ldl/EZuM01+dy8fQjfzujHSqRkg1ZlU3CyzOg8rI+nhwOiifmHsS+kOX4rZ5iS/kS8 p5M/JYGhanZaeXzPld5wJmwfEDtYx6u2t7KfOkQE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+f816042a7ae2225f25ba@syzkaller.appspotmail.com, Andreas Dilger , Jan Kara Subject: [PATCH 5.10 35/40] quota: Sanity-check quota file headers on load Date: Wed, 23 Dec 2020 16:33:36 +0100 Message-Id: <20201223150517.227345425@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201223150515.553836647@linuxfoundation.org> References: <20201223150515.553836647@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: linux-kernel@vger.kernel.org From: Jan Kara commit 11c514a99bb960941535134f0587102855e8ddee upstream. Perform basic sanity checks of quota headers to avoid kernel crashes on corrupted quota files. CC: stable@vger.kernel.org Reported-by: syzbot+f816042a7ae2225f25ba@syzkaller.appspotmail.com Reviewed-by: Andreas Dilger Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman --- fs/quota/quota_v2.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) --- a/fs/quota/quota_v2.c +++ b/fs/quota/quota_v2.c @@ -157,6 +157,25 @@ static int v2_read_file_info(struct supe qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk); qinfo->dqi_ops = &v2r1_qtree_ops; } + ret = -EUCLEAN; + /* Some sanity checks of the read headers... */ + if ((loff_t)qinfo->dqi_blocks << qinfo->dqi_blocksize_bits > + i_size_read(sb_dqopt(sb)->files[type])) { + quota_error(sb, "Number of blocks too big for quota file size (%llu > %llu).", + (loff_t)qinfo->dqi_blocks << qinfo->dqi_blocksize_bits, + i_size_read(sb_dqopt(sb)->files[type])); + goto out; + } + if (qinfo->dqi_free_blk >= qinfo->dqi_blocks) { + quota_error(sb, "Free block number too big (%u >= %u).", + qinfo->dqi_free_blk, qinfo->dqi_blocks); + goto out; + } + if (qinfo->dqi_free_entry >= qinfo->dqi_blocks) { + quota_error(sb, "Block with free entry too big (%u >= %u).", + qinfo->dqi_free_entry, qinfo->dqi_blocks); + goto out; + } ret = 0; out: up_read(&dqopt->dqio_sem);