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Date: Sun, 26 Oct 2014 15:26:04 +0100
From: Mateusz Guzik <mjguzik@gmail.com>
To: Tiwei Bie <btw@mail.ustc.edu.cn>
Subject: Re: Questions with 'MPASS(ngrp <= ngroups_max)' assertion in
 kern_setgroups()
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On Sun, Oct 26, 2014 at 09:47:01PM +0800, Tiwei Bie wrote:
> Hello, Mateusz!
> 
> The check in kern_setgroups's callers is:
> 
> 	if (gidsetsize > ngroups_max + 1)
> 		return (EINVAL);
> 
> So, gidsetsize could be (ngroups_max + 1). And under this condition, the assertion
> 
> 	MPASS(ngrp <= ngroups_max);
> 
> in kern_setgroups() will fail. One of them should be fixed.
> 
> 

Indeed, thanks.

Fixed in r273691.

-- 
Mateusz Guzik <mjguzik gmail.com>