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Date: Mon, 14 Jul 2003 22:16:20 +0200
From: Manfred Spraul <manfred@colorfullife.com>
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To: Michal Wronski <wrona@mat.uni.torun.pl>
CC: linux-kernel@vger.kernel.org, Christoph Hellwig <hch@lst.de>
Subject: Re: [RFC][PATCH] Posix Message Queues
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Hi Michal,

You've implemented mq_open() in user space by combining open()+ioctl() 
syscalls. I think it's racy:

What if two processes call
{
    fd = mq_open("dummy",O_CREAT,0777,{.mq_maxmsg=10000});
    mq_send = mq_send(fd,buf,10000,0);
}

I think setting the queue options and creating a new queue must be 
atomic, i.e. we need a new syscall.

Could you replace the printk's with Dprintk or something like that? User 
space misbehaviour such as bad pointers should not generate printk messages.

--
    Manfred