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Date: Thu, 29 Jul 2004 15:46:25 -0700
From: Andrew Morton <akpm@osdl.org>
To: Jan Blunck <j.blunck@tu-harburg.de>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ext2_readdir() filp->f_pos fix
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Jan Blunck <j.blunck@tu-harburg.de> wrote:
>
> If the whole inode is read, ext2_readdir() sets the f_pos to a multiple 

                    ^^ directory

> of the page size (because of the conditions of the outer for loop). This 
> sets the wrong f_pos for directory inodes on ext2 partitions with a 
> block size differing from the page size.

Interesting.  How did you actually notice this?  Is the same problem not present
in 2.4?

If the IS_ERR(page) returns true, should we not advance f_pos to skip this
page?

If the filldir() call returns non-zero your patch will leave f_pos pointing at
the problematic directory entry.  I'm not sure whether this is desirable.

hmm, ext2_readir() isn't propagating EFAULT back up to the caller.