Re: [PATCH 1/2] KEYS: Replace uid/gid/perm permissions checking with an ACL

From: Eric Biggers
Date: Tue Aug 06 2019 - 22:58:18 EST


On Tue, Jul 30, 2019 at 06:16:14PM -0700, Eric Biggers wrote:
> On Mon, Jul 29, 2019 at 08:49:56PM -0700, Eric Biggers wrote:
> > Hi David,
> >
> > On Tue, Jul 09, 2019 at 06:16:01PM -0700, Eric Biggers wrote:
> > > On Thu, May 23, 2019 at 04:58:27PM +0100, David Howells wrote:
> > > > Replace the uid/gid/perm permissions checking on a key with an ACL to allow
> > > > the SETATTR and SEARCH permissions to be split. This will also allow a
> > > > greater range of subjects to represented.
> > > >
> > >
> > > This patch broke 'keyctl new_session', and hence broke all the fscrypt tests:
> > >
> > > $ keyctl new_session
> > > keyctl_session_to_parent: Permission denied
> > >
> > > Output of 'keyctl show' is
> > >
> > > $ keyctl show
> > > Session Keyring
> > > 605894913 --alswrv 0 0 keyring: _ses
> > > 189223103 ----s-rv 0 0 \_ user: invocation_id
> > >
> > > - Eric
> >
> > This bug is still present in next-20190729.
> >
> > - Eric
>
> This fixes it:
>
> diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
> index aa3bfcadbc660..519c94f1cc3c2 100644
> --- a/security/keys/process_keys.c
> +++ b/security/keys/process_keys.c
> @@ -58,7 +58,7 @@ static struct key_acl session_keyring_acl = {
> .possessor_viewable = true,
> .nr_ace = 2,
> .aces = {
> - KEY_POSSESSOR_ACE(KEY_ACE__PERMS & ~KEY_ACE_JOIN),
> + KEY_POSSESSOR_ACE(KEY_ACE__PERMS),
> KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ),
> }
> };
>
>
> The old permissions were KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ, so
> I'm not sure why JOIN permission was removed?
>
> - Eric

Ping. This is still broken in linux-next.

- Eric