From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752114Ab2LUUq3 (ORCPT ); Fri, 21 Dec 2012 15:46:29 -0500 Received: from relay.parallels.com ([195.214.232.42]:45080 "EHLO relay.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750876Ab2LUUq1 convert rfc822-to-8bit (ORCPT ); Fri, 21 Dec 2012 15:46:27 -0500 Message-ID: <50D4CA90.60205@parallels.com> Date: Sat, 22 Dec 2012 00:46:08 +0400 From: Stanislav Kinsbursky User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Andrew Morton CC: , , , , , , , , , , , , , , , , , , , Sasha Levin , Wu Fengguang Subject: Re: [RFC PATCH v8 0/5] IPC: checkpoint/restore in userspace enhancements References: <20121024151555.5642.79086.stgit@localhost.localdomain> <20121218123601.113a29c0.akpm@linux-foundation.org> <50D28EC8.7000708@parallels.com> <20121220124751.d7ccbd8e.akpm@linux-foundation.org> In-Reply-To: <20121220124751.d7ccbd8e.akpm@linux-foundation.org> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8BIT X-Originating-IP: [173.199.153.135] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 21.12.2012 00:47, Andrew Morton пишет: > On Thu, 20 Dec 2012 08:06:32 +0400 > Stanislav Kinsbursky wrote: > >> 19.12.2012 00:36, Andrew Morton __________: >>> On Wed, 24 Oct 2012 19:34:51 +0400 >>> Stanislav Kinsbursky wrote: >>> >>>> This respin of the patch set was significantly reworked. Most part of new API >>>> was replaced by sysctls (by one per messages, semaphores and shared memory), >>>> allowing to preset desired id for next new IPC object. >>>> >>>> This patch set is aimed to provide additional functionality for all IPC >>>> objects, which is required for migration of these objects by user-space >>>> checkpoint/restore utils (CRIU). >>>> >>>> The main problem here was impossibility to set up object id. This patch set >>>> solves the problem by adding new sysctls for preset of desired id for new IPC >>>> object. >>>> >>>> Another problem was to peek messages from queues without deleting them. >>>> This was achived by introducing of new MSG_COPY flag for sys_msgrcv(). If >>>> MSG_COPY flag is set, then msgtyp is interpreted as message number. >>> According to my extensive records, Sasha hit a bug in >>> ipc-message-queue-copy-feature-introduced.patch and Fengguang found a >>> bug in >>> ipc-message-queue-copy-feature-introduced-cleanup-do_msgrcv-aroung-msg_copy-feature.patch >>> >>> It's not obvious (to me) that these things have been identified and >>> fixed. What's the status, please? >> Hello, Andrew. >> Fengguang's issue was solved by "ipc: simplify message copying" I sent you. >> But I can't find Sasha's issue. As I remember, there was some problem in >> early >> version of the patch set. But I believe its fixed now. > http://lkml.indiana.edu/hypermail/linux/kernel/1210.3/01710.html > > Subject: "ipc, msgqueue: NULL ptr deref in msgrcv" Ah, yes. Thanks. Hi found it in initial version of code, which was significantly changed (or cleaned and simplified) by further patch series. And I cant find out, how this can happen, because this patch he bisect to do not modify the queue itself, while he found the problem in testmsg.