On Sun, Mar 21, 2021 at 12:50:47PM -0600, Jonathan Corbet wrote:
> John Wood <john.wood@xxxxxxx> writes:
>
> > Add some info detailing what is the Brute LSM, its motivation, weak
> > points of existing implementations, proposed solutions, enabling,
> > disabling and self-tests.
> >
> > Signed-off-by: John Wood <john.wood@xxxxxxx>
> > ---
> > Documentation/admin-guide/LSM/Brute.rst | 278 ++++++++++++++++++++++++
> > Documentation/admin-guide/LSM/index.rst | 1 +
> > security/brute/Kconfig | 3 +-
> > 3 files changed, 281 insertions(+), 1 deletion(-)
> > create mode 100644 Documentation/admin-guide/LSM/Brute.rst
>
> Thanks for including documentation with the patch!
>
> As you get closer to merging this, though, you'll want to take a minute
> (OK, a few minutes) to build the docs and look at the result; there are
Thanks, I will do it.
> a number of places where you're not going to get what you expect. Just
> as an example:
>
> [...]
>
> > +Based on the above scenario it would be nice to have this detected and
> > +mitigated, and this is the goal of this implementation. Specifically the
> > +following attacks are expected to be detected:
> > +
> > +1.- Launching (fork()/exec()) a setuid/setgid process repeatedly until a
> > + desirable memory layout is got (e.g. Stack Clash).
> > +2.- Connecting to an exec()ing network daemon (e.g. xinetd) repeatedly until a
> > + desirable memory layout is got (e.g. what CTFs do for simple network
> > + service).
> > +3.- Launching processes without exec() (e.g. Android Zygote) and exposing state
> > + to attack a sibling.
> > +4.- Connecting to a fork()ing network daemon (e.g. apache) repeatedly until the
> > + previously shared memory layout of all the other children is exposed (e.g.
> > + kind of related to HeartBleed).
>
> Sphinx will try to recognize your enumerated list, but that may be a bit
> more punctuation than it is prepared to deal with; I'd take the hyphens
> out, if nothing else.
Thanks. I will fix this for the next version.
> > +These statistics are hold by the brute_stats struct.
> > +
> > +struct brute_cred {
> > + kuid_t uid;
> > + kgid_t gid;
> > + kuid_t suid;
> > + kgid_t sgid;
> > + kuid_t euid;
> > + kgid_t egid;
> > + kuid_t fsuid;
> > + kgid_t fsgid;
> > +};
>
> That will certainly not render the way you want. What you need here is
> a literal block:
>
> These statistics are hold by the brute_stats struct::
>
> struct brute_cred {
> kuid_t uid;
> kgid_t gid;
> kuid_t suid;
> kgid_t sgid;
> kuid_t euid;
> kgid_t egid;
> kuid_t fsuid;
> kgid_t fsgid;
> };
>
> The "::" causes all of the indented text following to be formatted
> literally.
Thanks a lot for your comments and guidance. I will build the docs and
check if the output is as I want.
> Thanks,
>
> jon
Regards,
John Wood
