From patchwork Fri Jun 19 14:33:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 224263 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=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 0C5F6C433E0 for ; Fri, 19 Jun 2020 14:38:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D58B720CC7 for ; Fri, 19 Jun 2020 14:38:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592577506; bh=YgsRd3RmLnVM1wIbfeCexFiwLKDhAcn/ht2Pqp1VxRY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ZOiXS2RrdvMeweHTzQoB7GrfQ9d/ikNG7Q5J1Rz8K2a0OX4uoULDbW2nNyABIJGHG 0WIQw0P2BzopMbGMrNn+iZDBTVlbQhH9FMvqPXZJwyKDKwAyA3mfR413C5vgyPXIIL 7Tlk+LuFzuR1Ob751gOC9ZPF0cTjdR1kIJVDOXuE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387866AbgFSOiZ (ORCPT ); Fri, 19 Jun 2020 10:38:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:55466 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733263AbgFSOiX (ORCPT ); Fri, 19 Jun 2020 10:38:23 -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 037F8208B8; Fri, 19 Jun 2020 14:38:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592577503; bh=YgsRd3RmLnVM1wIbfeCexFiwLKDhAcn/ht2Pqp1VxRY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M/48W09YnPyNygCB9U2ytLchTgfMr2XjG/163ThWRyVp954T+UQ2E2G+ZhMosKGby V3Adt/rweSCIWjiTXCVM6TILPB+fdGnY8S1WyR7Wr3bAlP7VUuYRt4sgHK0P6OV3ZP M30HZxC18/H8OF+y2HpCEOCDwqXzw8C2HMwXYQsA= 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 4.4 077/101] ext4: fix EXT_MAX_EXTENT/INDEX to check for zeroed eh_max Date: Fri, 19 Jun 2020 16:33:06 +0200 Message-Id: <20200619141618.042142094@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141614.001544111@linuxfoundation.org> References: <20200619141614.001544111@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -169,10 +169,13 @@ struct ext4_ext_path { (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) {