linux-kernel - Re: [PATCH] ubifs: Fix inode leak in xattr code

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Message-ID: <9db191c2-234c-3779-493a-7265409c2d69@nod.at>
Date:   Mon, 15 May 2017 19:57:47 +0200
From:   Richard Weinberger <richard@....at>
To:     dedekind1@...il.com, linux-mtd@...ts.infradead.org
Cc:     linux-kernel@...r.kernel.org, adrian.hunter@...el.com,
        stable@...r.kernel.org
Subject: Re: [PATCH] ubifs: Fix inode leak in xattr code

Artem,

Am 15.05.2017 um 18:05 schrieb Artem Bityutskiy:
> On Mon, 2017-05-15 at 17:22 +0200, Richard Weinberger wrote:
>> Alternatively we could add a iget_locked/drop_nlink/iput sequence to
>> ubifs_tnc_remove_ino(). But that will make unlink() much slower for
>> files
>> that contain xattrs.
> 
> At that level we'd need to do it for every xattr, even those that were
> never be accessed, which would be slow indeed.
> 
> But we really only need to check the inode cache: hey, icache, I am
> dying, and if you have any of my guys (xattrs), I want them to die with
> me. 
> 
> So the question is how to find our guys in the inode cache. I am not
> sure. Probably be we'd have to have our own list of cached inodes in
> the host inode, and maintain it.

BTW: Do you happen to know how other filesystems cache xattrs?
If they actually do.

Thanks,
//richard