> -----Original Message----- > From: James Morris [mailto:jmorris@xxxxxxxxx] > Sent: Thursday, September 27, 2018 3:47 PM > To: Casey Schaufler <casey@xxxxxxxxxxxxxxxx> > Cc: Schaufler, Casey <casey.schaufler@xxxxxxxxx>; kristen@xxxxxxxxxxxxxxx; > kernel-hardening@xxxxxxxxxxxxxxxxxx; Dock, Deneen T > <deneen.t.dock@xxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; Hansen, Dave > <dave.hansen@xxxxxxxxx>; linux-security-module@xxxxxxxxxxxxxxx; > selinux@xxxxxxxxxxxxx; arjan@xxxxxxxxxxxxxxx > Subject: Re: [PATCH v5 5/5] sidechannel: Linux Security Module for sidechannel > > On Thu, 27 Sep 2018, Casey Schaufler wrote: > > > On 9/27/2018 2:45 PM, James Morris wrote: > > > On Wed, 26 Sep 2018, Casey Schaufler wrote: > > > > > >> + /* > > >> + * Namespace checks. Considered safe if: > > >> + * cgroup namespace is the same > > >> + * User namespace is the same > > >> + * PID namespace is the same > > >> + */ > > >> + if (current->nsproxy) > > >> + ccgn = current->nsproxy->cgroup_ns; > > >> + if (p->nsproxy) > > >> + pcgn = p->nsproxy->cgroup_ns; > > >> + if (ccgn != pcgn) > > >> + return -EACCES; > > >> + if (current->cred->user_ns != p->cred->user_ns) > > >> + return -EACCES; > > >> + if (task_active_pid_ns(current) != task_active_pid_ns(p)) > > >> + return -EACCES; > > >> + return 0; > > > I really don't like the idea of hard-coding namespace security semantics > > > in an LSM. Also, I'm not sure if these semantics make any sense. > > > > Checks on namespaces where explicitly requested. > > By whom and what is the rationale? The rationale is to protect containers. Since those closest thing there is to a definition of containers is "uses namespaces" that becomes the focus. Separating them out does not make too much sense as I would expect someone concerned with one to be concerned with all. _______________________________________________ Selinux mailing list Selinux@xxxxxxxxxxxxx To unsubscribe, send email to Selinux-leave@xxxxxxxxxxxxx. To get help, send an email containing "help" to Selinux-request@xxxxxxxxxxxxx.
