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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 CD663C433DF for ; Fri, 19 Jun 2020 15:12:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9ABCC2186A for ; Fri, 19 Jun 2020 15:12:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592579573; bh=RTFHDTDn9cZ+Wm9DgGSO8r9TEyLNqlMrJWr1Kv2pi7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=oGkcUGkuqN89o8r3EUhtsrmuAUHGSS5BDrAvjGsDkrF66WTGFMSaIzCHKIRpeLtGs +W6pgLigC1gAqcjrs3JEb/flfT4dl1gcpv8+6JHONBfxc0jOcDIfiOxdHngWoSZnq4 gIUywf1A5MDiXMLdMFX/op/BCVJSZ8VFEgSXuuJc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403944AbgFSPMu (ORCPT ); Fri, 19 Jun 2020 11:12:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:43166 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392164AbgFSPMl (ORCPT ); Fri, 19 Jun 2020 11:12:41 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 054A7206FA; Fri, 19 Jun 2020 15:12:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592579560; bh=RTFHDTDn9cZ+Wm9DgGSO8r9TEyLNqlMrJWr1Kv2pi7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MtiTc1/k/J/Tvy9/9D/NvBd9tjAPGgDUVp4IAzhF/12Pn0A38H6TrDu9RMEnpJlly iPjA3GikeomDSABwg4qo8QoxNXyNyobzzOWrRCmiuBdZRiJccabZvphdpmyAKJYcAx rbWz99ZTC2XnbU0CikxPm7Usgx3PP0g7+CfNc7IM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Harshad Shirwadkar , Theodore Tso , stable@kernel.org Subject: [PATCH 5.4 181/261] ext4: fix EXT_MAX_EXTENT/INDEX to check for zeroed eh_max Date: Fri, 19 Jun 2020 16:33:12 +0200 Message-Id: <20200619141658.596612034@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141649.878808811@linuxfoundation.org> References: <20200619141649.878808811@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Harshad Shirwadkar commit c36a71b4e35ab35340facdd6964a00956b9fef0a upstream. If eh->eh_max is 0, EXT_MAX_EXTENT/INDEX would evaluate to unsigned (-1) resulting in illegal memory accesses. Although there is no consistent repro, we see that generic/019 sometimes crashes because of this bug. Ran gce-xfstests smoke and verified that there were no regressions. Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20200421023959.20879-2-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman --- fs/ext4/ext4_extents.h | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/fs/ext4/ext4_extents.h +++ b/fs/ext4/ext4_extents.h @@ -170,10 +170,13 @@ struct partial_cluster { (EXT_FIRST_EXTENT((__hdr__)) + le16_to_cpu((__hdr__)->eh_entries) - 1) #define EXT_LAST_INDEX(__hdr__) \ (EXT_FIRST_INDEX((__hdr__)) + le16_to_cpu((__hdr__)->eh_entries) - 1) -#define EXT_MAX_EXTENT(__hdr__) \ - (EXT_FIRST_EXTENT((__hdr__)) + le16_to_cpu((__hdr__)->eh_max) - 1) +#define EXT_MAX_EXTENT(__hdr__) \ + ((le16_to_cpu((__hdr__)->eh_max)) ? \ + ((EXT_FIRST_EXTENT((__hdr__)) + le16_to_cpu((__hdr__)->eh_max) - 1)) \ + : 0) #define EXT_MAX_INDEX(__hdr__) \ - (EXT_FIRST_INDEX((__hdr__)) + le16_to_cpu((__hdr__)->eh_max) - 1) + ((le16_to_cpu((__hdr__)->eh_max)) ? \ + ((EXT_FIRST_INDEX((__hdr__)) + le16_to_cpu((__hdr__)->eh_max) - 1)) : 0) static inline struct ext4_extent_header *ext_inode_hdr(struct inode *inode) {