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From: Roland McGrath <roland@redhat.com>
To: Oleg Nesterov <oleg@redhat.com>
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Cc: Andrew Morton <akpm@linux-foundation.org>,
       Jerome Marchand <jmarchan@redhat.com>,
       Denys Vlasenko <dvlasenk@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/4] ptrace: fix possible zombie leak on PTRACE_DETACH
In-Reply-To: Oleg Nesterov's message of  Thursday, 29 January 2009 05:29:23 +0100 <20090129042923.GA5118@redhat.com>
References: <20090129042923.GA5118@redhat.com>
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Date: Wed,  4 Feb 2009 17:30:42 -0800 (PST)
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ACK on the change, though looks different if you put __ptrace_detach in
ptrace.c with the earliar patch, as I suggest.  Also, I think this warrants
a comment for the release_task call mentioning briefly what it means:

	/*
	 * The flag means __ptrace_detach() determined that this child
	 * was a zombie that should have been auto-reaped already.
	 * Don't leak it.
	 */
	if (unlikely(dead))
		release_task(child);


Thanks,
Roland