linux-kernel - Re: [PATCH v2] fs: handle shrinker registration failure in sget

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20171123145540.GB21978@ZenIV.linux.org.uk>
Date:   Thu, 23 Nov 2017 14:55:40 +0000
From:   Al Viro <viro@...IV.linux.org.uk>
To:     Michal Hocko <mhocko@...nel.org>
Cc:     Dave Chinner <david@...morbit.com>, Jan Kara <jack@...e.cz>,
        Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>,
        LKML <linux-kernel@...r.kernel.org>,
        linux-fsdevel@...r.kernel.org,
        Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH v2] fs: handle shrinker registration failure in
 sget_userns

On Thu, Nov 23, 2017 at 03:35:37PM +0100, Michal Hocko wrote:
> Hopefully less screwed version.  But as I've said I am not really
> familiar with the code and do not feel competent to change it so please
> be very careful here. I've moved the shrinker registration to
> alloc_super which turned out to be simpler.

I don't get it.  Why the hell do we need all that PITA in the first place?
Just make sget_userns() end with
	if (unlikely(regsiter_shrinker(&s->s_shrink) != 0)) {
		deactivate_locked_super(s);
		s = ERR_PTR(-ENOMEM);
	}
	return s;
and be done with that.  All there is to it...