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_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 A4FF6C4332D for ; Mon, 28 Dec 2020 13:42:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 800552063A for ; Mon, 28 Dec 2020 13:42:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391903AbgL1Nl7 (ORCPT ); Mon, 28 Dec 2020 08:41:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:41436 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391669AbgL1NlM (ORCPT ); Mon, 28 Dec 2020 08:41:12 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9D81C207C9; Mon, 28 Dec 2020 13:40:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609162832; bh=kgnn3OX3Ha0ANEqkEYUXQQQ3PrttaXvaQuae7vSy3dE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HbOjcJ593+FfB5eTpgZoYu4+2to8zJ2+YvMRplQ83p4fCZupa5xUc3nwgO1FnTmG7 /yKdCdisYzfyJp4sQHa5O+MsawtehqeWfZuSU6uvYHUnASEUEBA/k4xSqqpQHQkiK8 /wNJ6n6Intp9ZGrJL2irVjtzN1eR2hWetGIJPpGc= 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 5.4 069/453] quota: Sanity-check quota file headers on load Date: Mon, 28 Dec 2020 13:45:05 +0100 Message-Id: <20201228124940.566777525@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124937.240114599@linuxfoundation.org> References: <20201228124937.240114599@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 @@ -159,6 +159,25 @@ 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);