linux-kernel - Re: [PATCH 4/7] Teach SELinux about a new userfaultfd class

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sat, 12 Oct 2019 16:08:54 -0700
From:   Andy Lutomirski <luto@...nel.org>
To:     Daniel Colascione <dancol@...gle.com>
Cc:     Linux API <linux-api@...r.kernel.org>,
        LKML <linux-kernel@...r.kernel.org>, lokeshgidra@...gle.com,
        Nick Kralevich <nnk@...gle.com>, nosh@...gle.com,
        Tim Murray <timmurray@...gle.com>
Subject: Re: [PATCH 4/7] Teach SELinux about a new userfaultfd class

On Sat, Oct 12, 2019 at 12:16 PM Daniel Colascione <dancol@...gle.com> wrote:
>
> Use the secure anonymous inode LSM hook we just added to let SELinux
> policy place restrictions on userfaultfd use. The create operation
> applies to processes creating new instances of these file objects;
> transfer between processes is covered by restrictions on read, write,
> and ioctl access already checked inside selinux_file_receive.

This is great, and I suspect we'll want it for things like SGX, too.
But the current design seems like it will make it essentially
impossible for SELinux to reference an anon_inode class whose
file_operations are in a module, and moving file_operations out of a
module would be nasty.

Could this instead be keyed off a new struct anon_inode_class, an
enum, or even just a string?

--Andy