Received: by 2002:ac0:a5a7:0:0:0:0:0 with SMTP id m36-v6csp857937imm; Mon, 9 Jul 2018 11:57:02 -0700 (PDT) X-Google-Smtp-Source: AAOMgpeyu2C5l0SaOYhcoodKnh8FCjL9YlmMlMvgGB2Mn6Uw/Ezbjf2pVbz2yrNTP9Zefq6vDFrg X-Received: by 2002:a65:44c3:: with SMTP id g3-v6mr19883116pgs.231.1531162622458; Mon, 09 Jul 2018 11:57:02 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1531162622; cv=none; d=google.com; s=arc-20160816; b=KqCBab4ZjEcXzhf4YHVlyxmrjFtPMkR6vtrbCr+YIu9Ez/HklZ5AAHgfN2ydLwe5p4 cazRTmyGSoZYWOgdsyWQfyZtWX9BT7dijW2fsNMXyXjoE2KikROIcjw0ULUesos3DNuP Lc1MynrMA7Wmp3fLpyuYdGyjXMy+DqiTGC6dXDlX0OaJJSSuZEmVc9vMLdvio+Av98jJ vCTFeIs7Dsge203K9Wm537L8q8STR1h84aou4OY9D60WmpTT3y7vZvYvIUzTvQ9T8xVo /5kHFNYBsZjKAsPUhQxFmJ5Z3i/a00qXLMZZBdrGQZb8U7FXMcQx+1CrAaQaXOV8sRj1 /UIA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:arc-authentication-results; bh=+gf0Py5qFJYkzjIcRnD+DwGc3fdpKwjqZlYLJZDJrkk=; b=riLpNpjEP6iwPH1QNwXQmRvZZa163pVzEW1+Pe3gpCWQBTEf+HKFPpCZeEVLSsxhXm zLo+sZNfrGuJvr1OiZD7VMXRz1Jccwc6DvtvkC+nWYXmMIWsxBqZ2nMu20TyGGGT29K3 SBLazlwRz9ra7UhTpmnsb7hoNbYXH7sK2z19mc7bK2NfsLn2K9fbLJENcfpXaZpk+CQP NNUbPzi6+cD3NQ6j2vGOP5nVuBc326zMLYpFqj51foKTiGlwimHQ8ig7Kc0KIKAQi1lp 0kQh+Yk26FYn6HiU/sdEeHJZZyXBNAsKktB5Cb5LzZKKWBad07DfsVOZw26jxrS56+WH 36Uw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id e14-v6si2236332pgg.345.2018.07.09.11.56.48; Mon, 09 Jul 2018 11:57:02 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754660AbeGISqu (ORCPT + 99 others); Mon, 9 Jul 2018 14:46:50 -0400 Received: from mx2.suse.de ([195.135.220.15]:47266 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754517AbeGISqu (ORCPT ); Mon, 9 Jul 2018 14:46:50 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id B16D5ADB1; Mon, 9 Jul 2018 18:46:48 +0000 (UTC) Date: Mon, 9 Jul 2018 11:46:38 -0700 From: Davidlohr Bueso To: Manfred Spraul Cc: Andrew Morton , Dmitry Vyukov , LKML , 1vier1@web.de, Kees Cook Subject: Re: [PATCH 05/12] ipc/util.c: correct comment in ipc_obtain_object_check Message-ID: <20180709184638.xj7tscl55zljboqx@linux-r8p5> References: <20180709151019.1336-1-manfred@colorfullife.com> <20180709151019.1336-6-manfred@colorfullife.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20180709151019.1336-6-manfred@colorfullife.com> User-Agent: NeoMutt/20170912 (1.9.0) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 09 Jul 2018, Manfred Spraul wrote: >The comment that explains ipc_obtain_object_check is wrong: >The function checks the sequence number, not the reference >counter. >Note that checking the reference counter would be meaningless: >The reference counter is decreased without holding any locks, >thus an object with kern_ipc_perm.deleted=true may disappear at >the end of the next rcu grace period. > >Signed-off-by: Manfred Spraul >Cc: Davidlohr Bueso Reviewed-by: Davidlohr Bueso