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From: Tiwei Bie <btw@mail.ustc.edu.cn>
To: mjg@freebsd.org
Subject: Questions with 'MPASS(ngrp <= ngroups_max)' assertion in
 kern_setgroups()
Date: Sun, 26 Oct 2014 21:47:01 +0800
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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.

Tiwei Bie