[PATCH v13 10/10] fs/ioctl: Add a comment to keep the logic in sync with the Landlock LSM

[Mickaël Salaün]

On Thu, Mar 28, 2024 at 09:08:13AM -0400, Paul Moore wrote:
> On Thu, Mar 28, 2024 at 8:11 AM Mickaël Salaün <mic at digikod.net> wrote:
> > On Wed, Mar 27, 2024 at 01:10:40PM +0000, Günther Noack wrote:
> > > Landlock's IOCTL support needs to partially replicate the list of
> > > IOCTLs from do_vfs_ioctl().  The list of commands implemented in
> > > do_vfs_ioctl() should be kept in sync with Landlock's IOCTL policies.
> > >
> > > Signed-off-by: Günther Noack <gnoack at google.com>
> > > ---
> > >  fs/ioctl.c | 3 +++
> > >  1 file changed, 3 insertions(+)
> > >
> > > diff --git a/fs/ioctl.c b/fs/ioctl.c
> > > index 1d5abfdf0f22..661b46125669 100644
> > > --- a/fs/ioctl.c
> > > +++ b/fs/ioctl.c
> > > @@ -796,6 +796,9 @@ static int ioctl_get_fs_sysfs_path(struct file *file, void __user *argp)
> > >   *
> > >   * When you add any new common ioctls to the switches above and below,
> > >   * please ensure they have compatible arguments in compat mode.
> > > + *
> > > + * The commands which are implemented here should be kept in sync with the IOCTL
> > > + * security policies in the Landlock LSM.
> >
> > Suggestion:
> > "with the Landlock IOCTL security policy defined in security/landlock/fs.c"
> 
> We really shouldn't have any comments or code outside of the security/
> directory that reference a specific LSM implementation.  I'm sure
> there are probably a few old comments referring to SELinux, but those
> are bugs as far as I'm concerned (if anyone spots one, please let me
> know or send me a patch!).
> 
> How about the following?
> 
> "The LSM list should also be notified of any command additions or

"The LSM mailing list..."

> changes as specific LSMs may be affected."

Looks good.

> 
> -- 
> paul-moore.com
>