Re: [PATCH 03/18] ovl: stack miscattr

[Miklos Szeredi]

On Fri, Feb 5, 2021 at 4:25 PM Miklos Szeredi <miklos@xxxxxxxxxx> wrote:
>
> On Fri, Feb 5, 2021 at 12:49 AM Vivek Goyal <vgoyal@xxxxxxxxxx> wrote:
>
> > > +int ovl_miscattr_set(struct dentry *dentry, struct miscattr *ma)
> > > +{
> > > +     struct inode *inode = d_inode(dentry);
> > > +     struct dentry *upperdentry;
> > > +     const struct cred *old_cred;
> > > +     int err;
> > > +
> > > +     err = ovl_want_write(dentry);
> > > +     if (err)
> > > +             goto out;
> > > +
> > > +     err = ovl_copy_up(dentry);
> > > +     if (!err) {
> > > +             upperdentry = ovl_dentry_upper(dentry);
> > > +
> > > +             old_cred = ovl_override_creds(inode->i_sb);
> > > +             /* err = security_file_ioctl(real.file, cmd, arg); */
> >
> > Is this an comment intended?
>
> I don't remember, but I guess not.  Will fix and test.

Sorry, yes, problem is that there's no file pointer available at this point.

Fix is probably to introduce security_inode_miscattr_perm() hook.

Thanks,
Miklos