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=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 2C1E3C43441 for ; Mon, 19 Nov 2018 16:59:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6D62214F1 for ; Mon, 19 Nov 2018 16:59:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="1U0N32JE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6D62214F1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404808AbeKTDXh (ORCPT ); Mon, 19 Nov 2018 22:23:37 -0500 Received: from mail.kernel.org ([198.145.29.99]:35672 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404341AbeKTDXg (ORCPT ); Mon, 19 Nov 2018 22:23:36 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 787012151B; Mon, 19 Nov 2018 16:59:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542646761; bh=SXPBEUsrtImy4DfNz+V55AVF/37BeJ4SvllIM+ZlVqk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1U0N32JEu6gGIlRV1qyslVKekAarQHhNs9GavcANzvzHXBmy8ur1pRQWpNaRgiyTx A/IT2+VQC7m3W30z2dCmoeByTMReF479ATzylVavccU5lLCr/siKwOkIxnNk7S3y0A v0aqCEpPx0dGpJ4hxoIHa9W0ULsPMjiFM+ViUWq8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anatoly Trosinenko , Nicolas Pitre Subject: [PATCH 4.4 081/160] Cramfs: fix abad comparison when wrap-arounds occur Date: Mon, 19 Nov 2018 17:28:40 +0100 Message-Id: <20181119162639.071893784@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181119162630.031306128@linuxfoundation.org> References: <20181119162630.031306128@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicolas Pitre commit 672ca9dd13f1aca0c17516f76fc5b0e8344b3e46 upstream. It is possible for corrupted filesystem images to produce very large block offsets that may wrap when a length is added, and wrongly pass the buffer size test. Reported-by: Anatoly Trosinenko Signed-off-by: Nicolas Pitre Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- fs/cramfs/inode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/cramfs/inode.c +++ b/fs/cramfs/inode.c @@ -185,7 +185,8 @@ static void *cramfs_read(struct super_bl continue; blk_offset = (blocknr - buffer_blocknr[i]) << PAGE_CACHE_SHIFT; blk_offset += offset; - if (blk_offset + len > BUFFER_SIZE) + if (blk_offset > BUFFER_SIZE || + blk_offset + len > BUFFER_SIZE) continue; return read_buffers[i] + blk_offset; }