> -----Original Message----- > From: James Morris [mailto:jmor...@namei.org] > Sent: Thursday, September 27, 2018 3:47 PM > To: Casey Schaufler <ca...@schaufler-ca.com> > Cc: Schaufler, Casey <casey.schauf...@intel.com>; kris...@linux.intel.com; > kernel-harden...@lists.openwall.com; Dock, Deneen T > <deneen.t.d...@intel.com>; linux-ker...@vger.kernel.org; Hansen, Dave > <dave.han...@intel.com>; linux-security-mod...@vger.kernel.org; > selinux@tycho.nsa.gov; ar...@linux.intel.com > 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@tycho.nsa.gov To unsubscribe, send email to selinux-le...@tycho.nsa.gov. To get help, send an email containing "help" to selinux-requ...@tycho.nsa.gov.
