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Date: Mon, 16 May 2016 22:47:12 -0500
From: "Serge E. Hallyn" <serge@hallyn.com>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>,
	Djalal Harouni <tixxdz@gmail.com>, Chris Mason <clm@fb.com>,
	tytso@mit.edu, Serge Hallyn <serge.hallyn@canonical.com>,
	Josh Triplett <josh@joshtriplett.org>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	Andy Lutomirski <luto@kernel.org>,
	Seth Forshee <seth.forshee@canonical.com>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-security-module@vger.kernel.org,
	Dongsu Park <dongsu@endocode.com>,
	David Herrmann <dh.herrmann@googlemail.com>,
	Miklos Szeredi <mszeredi@redhat.com>,
	Alban Crequy <alban.crequy@gmail.com>,
	Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [RFC 1/1] shiftfs: uid/gid shifting bind mount
Message-ID: <20160517034712.GA10436@mail.hallyn.com>
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 <20160516194117.GA29354@ubuntumail>
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On Mon, May 16, 2016 at 10:28:32PM -0400, James Bottomley wrote:
> On Mon, 2016-05-16 at 19:41 +0000, Serge Hallyn wrote:
> > Hey James,
> > 
> > I probably did something wrong - but i applied your patch onto 4.6,
> > compiled in shiftfs, did
> > 
> > mount -t shiftfs -o uidmap=0:100000:65536,gidmap=0:100000:65536
> > /home/ubuntu /mnt
> > 
> > and ls segfaults and gives me kernel syslog msgs like:
> 
> Hm, it looks to be something IMA related, since the SUSE default is no
> IMA and this BUG in the filesystem is to do with the IMA version of
> i_readcount_dec.  I'll recompile my kernel to see if I can reproduce. 
>  Just in case, what's the underlying filesystem on /home/ubuntu?

It was ext4