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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1AD0BC76188 for ; Tue, 4 Apr 2023 01:08:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231933AbjDDBH6 (ORCPT ); Mon, 3 Apr 2023 21:07:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35862 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229684AbjDDBH5 (ORCPT ); Mon, 3 Apr 2023 21:07:57 -0400 Received: from mail-oa1-x31.google.com (mail-oa1-x31.google.com [IPv6:2001:4860:4864:20::31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82095269E for ; Mon, 3 Apr 2023 18:07:56 -0700 (PDT) Received: by mail-oa1-x31.google.com with SMTP id 586e51a60fabf-17683b570b8so32782737fac.13 for ; Mon, 03 Apr 2023 18:07:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1680570476; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=2qpGvufRL21Qgh/K6vS9SQYjOD5hNXpcU2M8DyK23pQ=; b=CKDZYmc0msmHg/I5U/sqq7nb8Eh28vhVCXYpYO1pBjPVjh6LpVRl2g46mhLrwaHflz 71Ycn9mNiNDFBJQbpJLoc1vyOJAnGVZ2xjs1QNTzvyDvyqmSmKY9/FfmMX+e2mnZMH+H DEaj+QMmkGeNJJvyV/T8gn1HaXnWq+cTH14p2NieXCupYU2cmFKOg7cXm0J8oj1Z6qSh T4XSy4OBMu9fL9GAEXXiHUTuK2TqS9/vINcgfXuekSK4SfLPA7xoMNOjseT0qPGd6Hml qjX7lYz/pLVWbw1tabtGF3RzwCG7byaQjy/RjspMTIqutZ4hYxZnLCDmXqAtKyl4+1eS Jo6Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680570476; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=2qpGvufRL21Qgh/K6vS9SQYjOD5hNXpcU2M8DyK23pQ=; b=c/Pgs9OkuZDJnoqDY9d2k7Y6n/V5DDAULiUpBFHASBV/8NdutzktgPuC2/Z3MK+G9+ 7ER1r25YsKjn1M+gK/1dh18Kt47vyZLr0HcIoI+TFMWkeNgEl14j6FvlEBuF2N0+OCYH CaV3s6hxM2l/GSEuv2hDqUXvXLIxK5avoUAUnEwjGSwcmQ3l2KPmyEeV8mPENH/9CoIC scFLT8Pu7s+uWliATHdTKsRiShwvZKnbve1Ra4Uof0qxvkkVS984aP4EMMwXmx4ouTg3 LLL3pvMvINZumR8pc4SYqiz2zbYt/1KLxDTAXTIP1ET+HFM5Uj9bHakrkkdvE4b+qdvy ie+Q== X-Gm-Message-State: AAQBX9d/8jnpUOC2SPYAPLlytqMul5iuBJVfdsSsqegVLwioCHfR49h7 H1itmqMzk11oy71e2IWj3dJqJvlVVzNCQGJlklo= X-Google-Smtp-Source: AKy350arZSc8powkSpIdXPuONpjvmwdVG3MJ6B/hnhL9Q1mGDIbyQglb6u2pktxFEwGW+a7qmuu/23hznXXuDE6WgEA= X-Received: by 2002:a05:6870:12d0:b0:17e:2ddf:b23c with SMTP id 16-20020a05687012d000b0017e2ddfb23cmr488079oam.0.1680570475807; Mon, 03 Apr 2023 18:07:55 -0700 (PDT) MIME-Version: 1.0 References: <20230402130557.17662-1-worldhello.net@gmail.com> In-Reply-To: From: Jiang Xin Date: Tue, 4 Apr 2023 09:07:43 +0800 Message-ID: Subject: Re: [PATCH] object-info: init request_info before reading arg To: Junio C Hamano Cc: Git List , Bruno Albuquerque , Jiang Xin Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Tue, Apr 4, 2023 at 12:36=E2=80=AFAM Junio C Hamano = wrote: > > Jiang Xin writes: > > > From: Jiang Xin > > > > When retrieving object info via capability "object-info", we store the > > command args into a requested_info variable, but forget to initialize > > it. Initialize the variable before use to prevent unexpected output. > > Good eyes. We read the request packets to decide if we want to flip > the .size member of the structure, but the result would not make > much sense if the structure starts with a random garbage in it. > > I wonder if we can tell our compilers (or runtime checker) to help > catch a mistake like this. Did you see our sanitizers complain, or > something? I accidentally came across this issue when I wanted to implement a new similar capability. I'm curious why adding "-Wuninitialized" or "-Wmaybe-uninitialized" to gcc fails to spot this case.