On Wed, Sep 30, 2015 at 11:27:34AM -0700, Andy Lutomirski wrote: > On Wed, Sep 30, 2015 at 11:13 AM, Tycho Andersen > <tycho.ander...@canonical.com> wrote: > > This patch introduces the concept of a seccomp fd, with a similar interface > > and usage to ebpf fds. Initially, one is allowed to create, install, and > > dump these fds. Any manipulation of seccomp fds requires users to be root > > in their own user namespace, matching the checks done for > > SECCOMP_SET_MODE_FILTER. > > > > Installing a filterfd has some gotchas, though. Andy mentioned previously > > that we should restrict installation to filter fds whose parent is already > > in the filter tree. This doesn't quite work in the case of created seccomp > > fds, since once you install a filter fd, you can't install any other filter > > fd since it has no parent and there is no way to "pre-chain" filters before > > installing them. > > ISTM, if we like the seccomp fd approach, we should have them be > created with a parent already set. IOW the default should be that > their parent is the creator's seccomp fd and, if needed, creators > could specify a different parent.
Allowing people doing SECCOMP_FD_NEW to specify a parent fd would work. Then we can disallow installing a seccomp fd if its parent is not the current filter, and get rid of the whole mess with prev locking and all that. Tycho -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
