Re: [Dazuko-devel] DazukoFS 3.1.4-rc1 posted

[John Ogness]

On 2010-10-19, Lino Sanfilippo <address@hidden> wrote:
>> IMPORTANT: This new version fixes an inode leak when removing
>> directories.
>
> I assume the fix is
>    dentry->d_inode->i_nlink = get_lower_inode(dentry->d_inode)->i_nlink;
> in dazukofs_rmdir(), right?

Correct.

> I could not find anything similar in ecryptfs code. Is this also a
> bug in ecryptfs?

I assume that ecryptfs also has this problem. But I did not take the
time to verify this.

> I looked into the vfs code by i could not find out what exactly the
> effect of the line above is.  A few words to clarify this would be
> great.

The bug (and fix) were reported on the Dazuko Savannah page:

http://savannah.nongnu.org/bugs/?func=detailitem&item_id=30982

There you will also see a simple procedure to verify the bug. This
could be done very quickly and easily to verify that ecryptfs also has
the problem.

When you look at other filesystems, you see that they indeed decrement
the i_nlink count by 2 when rmdir is called. Rather than performing
this ourself, we just copy the count from the lower filesystem. Since
ecryptfs does not do this, I expect ecryptfs to also have an inode
leak with rmdir.

John Ogness

-- 
Dazuko Maintainer