Messages in this thread | | | From | Andrew Lutomirski <> | Date | Thu, 24 May 2012 16:43:29 -0700 | Subject | Re: [RFC PATCH 0/3] move the secure_computing call |
| |
On Thu, May 24, 2012 at 4:40 PM, James Morris <jmorris@namei.org> wrote: > On Thu, 24 May 2012, Will Drewry wrote: > >> As is, the biggest benefit of this change is just setting consistent >> expectations in what the ptrace/seccomp interactions should be. The >> current ability for ptrace to "bypass" secure computing (by remapping >> allowed system calls) is not necessarily a problem, but it is not >> necessarily intuitive behavior. > > Indeed -- while the purpose of seccomp is to reduce the attack surface of > the syscall interface, if a user allows ptrace, attackers will definitely > see that as an attack vector, if it allows them to increase that attack > surface. > > It at least needs to be well-documented.
IMO the behavior should change. Alternatively, a post-ptrace syscall should have to pass the *tracer's* seccomp filter, but that seems overcomplicated and confusing.
OTOH, allowing ptrace in a seccomp filter is asking for trouble anyway -- if you can ptrace something outside the sandbox, you've escaped.
--Andy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |