Re: [PATCH 2/4] generic: ensure we drop suid after fallocate

["Darrick J. Wong" <djwong@kernel.org>]

On Sun, Apr 17, 2022 at 11:40:32PM +0800, Eryu Guan wrote:
> On Fri, Apr 15, 2022 at 04:42:33PM +0300, Amir Goldstein wrote:
> > > Hi Darrick, that's another story, you don't need to worry about that in this case :)
> > > I'd like to ack this patch, but hope to move it from generic/ to shared/ . Maybe
> > > Eryu can help to move it, or I can do that after I get the push permission.
> > >
> > > The reason why I intend moving it to shared is:
> > > Although we are trying to get rid of tests/shared/, but the tests/shared/ still help to
> > > remind us what cases are still not real generic cases. We'll try to help all shared
> > > cases to be generic. When the time is ready, I'd like to move this case to generic/
> > > and change _supported_fs from "xfs btrfs ext4" to "generic".
> > >
> > 
> > Sorry, but I have to object to this move.
> > I do not think that is what tests/shared should be used for.
> 
> After reading all the discussions, I prefer option 2 here as well, it's
> testing for a security bug, and all affected filesystems should be fixed,
> and a new failure will remind people there's something to be fixed.

Ok.  I'll put it back to _supported_fs generic and leave the tests in
tests/generic/.  Thank you for making a decision. :)

--D

> > 
> > My preferences are:
> > 1. _suppoted_fs generic && _require_xfs_io_command "finsert"
> 
> As btrfs doesn't support "finsert", so the falloc/fpunch tests won't run
> on btrfs, and we miss test coverage there.
> 
> > 2. _suppoted_fs generic
> > 3. _supported_fs xfs btrfs ext4 (without moving to tests/shared)
> 
> This is weired. And if we really want to restrict the new behavior
> within xfs, btrfs and ext4 for now, then I can live with a whitelist
> _require rule, and a good comment on it.
> 
> Thanks,
> Eryu