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Date: Fri, 02 Aug 2002 15:46:45 +0200
From: Kasper Dupont <kasperd@daimi.au.dk>
Organization: daimi.au.dk
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To: Linux-Kernel <linux-kernel@vger.kernel.org>
Subject: [RFC] Race condition?
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Is there a race condition in this piece of code from do_fork in
linux/kernel/fork.c? I cannot see what prevents two processes
from calling this at the same time and both successfully fork
even though the user had only one process left.

        if (atomic_read(&p->user->processes) >= p->rlim[RLIMIT_NPROC].rlim_cur
                      && !capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE))
                goto bad_fork_free;

        atomic_inc(&p->user->__count);
        atomic_inc(&p->user->processes);

-- 
Kasper Dupont -- der bruger for meget tid p? usenet.
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