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Subject: Re: [PATCH 7/7] sysvipc_find_ipc should increase position index
To:     Andreas Schwab <schwab@suse.de>
Cc:     linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        NeilBrown <neilb@suse.com>, Waiman Long <longman@redhat.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Oberparleiter <oberpar@linux.ibm.com>
References: <b7a20945-e315-8bb0-21e6-3875c14a8494@virtuozzo.com>
 <mvm4ksupdgr.fsf@suse.de>
From:   Vasily Averin <vvs@virtuozzo.com>
Message-ID: <ad24ee52-21a8-3ff0-e968-63d315472b91@virtuozzo.com>
Date:   Wed, 6 May 2020 08:03:52 +0300
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On 5/5/20 7:13 PM, Andreas Schwab wrote:
> I think this is causing this bug (seen on 5.6.8):

thank you for reporting,
yes, you are right, it's my fault
patch incorrectly updated *new_pos in case of found entry

> # ipcs -q
> 
> ------ Message Queues --------
> key        msqid      owner      perms      used-bytes   messages    
> 0x7c982867 3          root       644        0            0           
> 0x7c982867 3          root       644        0            0           
> 0x7c982867 3          root       644        0            0           
> 0x7c982867 3          root       644        0            0           

Thank you,
	Vasily Averin