From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Vegard Nossum" <vegard.nossum@gmail.com>
Subject: Re: latest -git: A peculiar case of a stuck process (ext3/sched-related?)
Date: Fri, 18 Jul 2008 12:39:18 +0200
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	"Ingo Molnar" <mingo@elte.hu>,
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To: "Andrew Morton" <akpm@linux-foundation.org>
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On Fri, Jul 18, 2008 at 12:32 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> On Fri, 18 Jul 2008 12:17:17 +0200 "Vegard Nossum" <vegard.nossum@gmail.com> wrote:
>
>> And the ext3_find_entry() corresponds to this line:
>>
>>         for (; de < top; de = ext3_next_entry(de)) /* <--- HERE! */
>>         if (ext3_match (namelen, name, de)) {
>>                 if (!ext3_check_dir_entry("ext3_find_entry",
>>                                           dir, de, bh,
>>                           (block<<EXT3_BLOCK_SIZE_BITS(sb))
>>                                   +((char *)de - bh->b_data))) {
>>                         brelse (bh);
>>                         *err = ERR_BAD_DX_DIR;
>>                         goto errout;
>>                 }
>>                 *res_dir = de;
>>                 dx_release (frames);
>>                 return bh;
>>         }
>>
>> Is it possible that this loop can get stuck with a corrupt filesystem image?
>
> yup.  ext2 did that a couple of times.  See the explicit check for
> de->rec_len == 0 in ext2_find_entry().
>
> We fixed one filesystem and forgot the others.  Again.

Wow, that change is OLD, though:

commit aa4f3f285643956bb614cf7b8f88e15f3a375886
Author: Andrew Morton <akpm@zip.com.au>
Date:   Mon Apr 29 23:51:34 2002 -0700

    [PATCH] ext2 directory handling

Will you also send the patch for ext3? :-)


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036