Re: [PATCH] reiserfs: fix spurious multiple-fill in reiserfs_readdir_dentry

[Jan Kara <jack@suse.cz>]

On Fri 31-05-13 15:07:52, Jeff Mahoney wrote:
> After sleeping for filldir(), we check to see if the file system has
> changed and research. The next_pos pointer is updated but its value
> isn't pushed into the key used for the search itself. As a result,
> the search returns the same item that the last cycle of the loop did
> and filldir() is called multiple times with the same data.
> 
> The end result is that the buffer can contain the same name multiple
> times. This can be returned to userspace or used internally in the
> xattr code where it can manifest with the following warning:
> 
> jdm-20004 reiserfs_delete_xattrs: Couldn't delete all xattrs (-2)
> 
> reiserfs_for_each_xattr uses reiserfs_readdir_dentry to iterate over
> the xattr names and ends up trying to unlink the same name twice. The
> second attempt fails with -ENOENT and the error is returned. At some
> point I'll need to add support into reiserfsck to remove the orphaned
> directories left behind when this occurs.
> 
> The fix is to push the value into the key before researching.
  The patch looks good. I've added it to my tree.

								Honza
> 
> Signed-off-by: Jeff Mahoney <jeffm@suse.com>
> ---
>  fs/reiserfs/dir.c |    2 ++
>  1 file changed, 2 insertions(+)
> 
> --- a/fs/reiserfs/dir.c	2013-05-31 14:29:35.945840685 -0400
> +++ b/fs/reiserfs/dir.c	2013-05-31 14:30:05.473952112 -0400
> @@ -204,6 +204,8 @@ int reiserfs_readdir_dentry(struct dentr
>  				next_pos = deh_offset(deh) + 1;
>  
>  				if (item_moved(&tmp_ih, &path_to_entry)) {
> +					set_cpu_key_k_offset(&pos_key,
> +							     next_pos);
>  					goto research;
>  				}
>  			}	/* for */
> 
> 
> -- 
> Jeff Mahoney
-- 
Jan Kara <jack@suse.cz>
SUSE Labs, CR