Re: [PATCH v2 selinux] selinux: remove unneeded ipv6 hook wrappers

From: Ondrej Mosnacek
Date: Mon Oct 11 2021 - 14:21:11 EST


On Mon, Oct 11, 2021 at 7:10 PM Paul Moore <paul@xxxxxxxxxxxxxx> wrote:
> On Mon, Oct 11, 2021 at 10:25 AM Florian Westphal <fw@xxxxxxxxx> wrote:
> >
> > Netfilter places the protocol number the hook function is getting called
> > from in state->pf, so we can use that instead of an extra wrapper.
> >
> > Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
> > ---
> > v2: add back '#endif /* CONFIG_NETFILTER */' erronously axed in v1.
> > Applies to 'next' branch of
> > https://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git/
> >
> > security/selinux/hooks.c | 52 ++++++++++------------------------------
> > 1 file changed, 12 insertions(+), 40 deletions(-)
>
> ...
>
> > diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> > index e7ebd45ca345..831b857d5dd7 100644
> > --- a/security/selinux/hooks.c
> > +++ b/security/selinux/hooks.c
> > @@ -7470,38 +7442,38 @@ DEFINE_LSM(selinux) = {
> >
> > static const struct nf_hook_ops selinux_nf_ops[] = {
> > {
> > - .hook = selinux_ipv4_postroute,
> > + .hook = selinux_hook_postroute,
> > .pf = NFPROTO_IPV4,
> > .hooknum = NF_INET_POST_ROUTING,
> > .priority = NF_IP_PRI_SELINUX_LAST,
> > },
>
> Thanks for the patch Florian, although the name "selinux_hook_*" seems
> a bit ambiguous to me, after all we have a little more than 200
> "hooks" in the SELinux LSM implementation. Would you be okay with
> calling the netfilter hook functions "selinux_nf_*" or something
> similar? If you don't have time I can do the rename during the merge
> assuming we can all agree on a name.

Since selinux_ip_forward() and selinux_ip_postroute() are used only in
the hook functions, how about changing their signature and using them
as hooks directly? That would solve the naming and also remove a few
extra lines of boilerplate.

--
Ondrej Mosnacek
Software Engineer, Linux Security - SELinux kernel
Red Hat, Inc.