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To: Andi Kleen <andi@firstfloor.org>
Cc: akpm@osdl.org, wli@holomorphy.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Terminate hugetlbfs mount argument list
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References: <20080311224204.GA16719@basil.nowhere.org>
From: Roland Dreier <rdreier@cisco.com>
Date: Tue, 11 Mar 2008 15:48:46 -0700
In-Reply-To: <20080311224204.GA16719@basil.nowhere.org> (Andi Kleen's message of "Tue, 11 Mar 2008 23:42:04 +0100")
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 > The match_table_t for the mount arguments in hugetlbfs wasn't 
 > terminated as match_tokens expect. I didn't see a crash just code
 > audit, but it's still safer to terminate it in case the variables after
 > that in .data are not NULL.

I think you're misunderstanding the match_token() interface.  The
comment before match_token() says:

 * @table: match_table_t describing the set of allowed option tokens and the
 * arguments that may be associated with them. Must be terminated with a
 * &struct match_token whose pattern is set to the NULL pointer.

and that's exactly what already exists here:

 	{Opt_gid,	"gid=%u"},
 	{Opt_err,	NULL},

So your patch is effectively an obfuscated NOP.

 - R.