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=-3.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 F3977C433E1 for ; Tue, 25 Aug 2020 21:10:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C2A2E20665 for ; Tue, 25 Aug 2020 21:10:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="o1+Ga/3+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726542AbgHYVKz (ORCPT ); Tue, 25 Aug 2020 17:10:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39448 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726149AbgHYVKx (ORCPT ); Tue, 25 Aug 2020 17:10:53 -0400 Received: from mail-ej1-x635.google.com (mail-ej1-x635.google.com [IPv6:2a00:1450:4864:20::635]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E0C4AC061574 for ; Tue, 25 Aug 2020 14:10:52 -0700 (PDT) Received: by mail-ej1-x635.google.com with SMTP id d26so10253ejr.1 for ; Tue, 25 Aug 2020 14:10:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition; bh=M61YkM2EGZM7C+AO87egaaUA1bKcbiaDgTY2Z2xt/1E=; b=o1+Ga/3+vG4PKIXBhnjvOF5prfySob+Zzq+3ml09CSzQQYHE8gdwHaZliOs5WeEMOB /lj8GuMHA6cHpLBbl0GSd6ygzopcZlmiobNRNtMVkUfArhOhKTMdzRo68tIysMk2g3wI oW3gGhiDe7ayp4QFEzsQ4a/JGi1OIU5LFBNhb4gTyBatCBFzoOYiCIcpDp+ECDRhqO0O W3AdsA/X30hUoEgGVSp5xBi7OvFaRBbJUxCgBqmWzVOXBGYUtcveUOxHTgpYYtl4Y/5S xP05ZFF9mbezgLvfhGzrgxYezhbwMsEkvmbxzXRnm8a38IMVmtMpxn6L7n4bv6XrpvBP un8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition; bh=M61YkM2EGZM7C+AO87egaaUA1bKcbiaDgTY2Z2xt/1E=; b=DIvd9TRzG4vVqy8OHU+kUnBfkn6u2xRn920w+Qv0xflgMYEW5TC+c5DoleUlAUzvta M8G0jT4nbmr1SZY0jtSSbC7AYmtlKtQ/THRPpXCX/w2Sd8UYAKm3VEhljpuvF/KZ4Fc5 cTvxq+wLg6x1Nu7CsoAwK9dhYDa9P397CWGahPRs6xpX0/b5uS5uZ/c/6PcftIrt0Z4u Ip7ockMhDwLKOpFc8by4cmTiZ/n7jDAjdoCuX2fCWNmppYTn9iquomHSxZX2Z716a7qL +teuPZ2GNqsTebF6e18Ecv9x2nhNC3FdvCeSuZ5EuzTyOvx24sbFKqLIU/vuKmOXRGdu CwrA== X-Gm-Message-State: AOAM5318teaia34FNehNGwyyfQ3w+7lXXT/a8q6FhGh7udOFuMliaqqf 48nUwcqZSMxSngdv8yN6zMYDSL1TWQ== X-Google-Smtp-Source: ABdhPJyOp2ieRNfsu+2E3EFLqHWekRIAbODJGn+pSjsR3EIrE6WSALeNWEVBKLUkpORtoi46at8l6w== X-Received: by 2002:a17:906:a085:: with SMTP id q5mr12319275ejy.136.1598389851377; Tue, 25 Aug 2020 14:10:51 -0700 (PDT) Received: from localhost.localdomain ([46.53.251.143]) by smtp.gmail.com with ESMTPSA id ca3sm157967edb.72.2020.08.25.14.10.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Aug 2020 14:10:50 -0700 (PDT) Date: Wed, 26 Aug 2020 00:10:48 +0300 From: Alexey Dobriyan To: linux-xfs@vger.kernel.org Cc: darrick.wong@oracle.com Subject: "signed < sizeof()" bug in xfs_attr_shortform_verify() ? Message-ID: <20200825211048.GA2162993@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org xfs_attr_shortform_verify() contains the following code: int64_t size = ifp->if_bytes; /* * Give up if the attribute is way too short. */ if (size < sizeof(struct xfs_attr_sf_hdr)) return __this_address; In general "if (signed < sizeof())" is wrong because of how type promotions work. Such check won't catch small negative values. I don't know XFS well enough to know if negative values were excluded somewhere above the callchain, but maybe someone else does.