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

[Jeff Mahoney <jeffm@suse.com>]

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On 5/31/13 3:31 PM, Jan Kara wrote:
> 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.

Thanks, Jan.

I have a few other fixes that we've had in SLE11 for a while that should
probably make it into the next release as well.

I've published them at:
git://jeffreymahoney.com/linux/linux-upstream reiserfs-for-3.10

There are 3 patches, HEAD is 7c769dbb (reiserfs: fix problems with
chowning setuid file w/ xattrs)

It includes this fix.

-Jeff

> 
> 								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


-- 
Jeff Mahoney
SUSE Labs


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