From patchwork Mon Dec 28 12:46:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 353146 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_RED, 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 33445C43331 for ; Mon, 28 Dec 2020 16:06:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3ED52084D for ; Mon, 28 Dec 2020 16:06:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389001AbgL1NZq (ORCPT ); Mon, 28 Dec 2020 08:25:46 -0500 Received: from mail.kernel.org ([198.145.29.99]:54456 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388995AbgL1NZq (ORCPT ); Mon, 28 Dec 2020 08:25:46 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6B8BD22A84; Mon, 28 Dec 2020 13:25:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609161906; bh=RoysQs+gxXGp63xNUERVOgDtnxepKhU9f5tOZDw9G7M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l+9/DXTCbpnI+ZKHXtLYN/pEJPSH59xk8MZcRxcF63PuojAxJvfYyRHvEwmsOcFl0 kQQjgHaFi/lkdeG1zkq9oHnhe2rYnk0arY44Jj9+MfshEIy5B54VfR1v4iAt9ETFxu oB0M17y6HhpMlTDrMyJrAd0n/gsbgD3MCU6znWwI= 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 4.19 092/346] quota: Sanity-check quota file headers on load Date: Mon, 28 Dec 2020 13:46:51 +0100 Message-Id: <20201228124924.248082355@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124919.745526410@linuxfoundation.org> References: <20201228124919.745526410@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -158,6 +158,25 @@ 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);