On 06/20, Andy Lutomirski wrote: > > On Mon, Jun 20, 2016 at 8:24 AM, Oleg Nesterov <o...@redhat.com> wrote: > > > > How about the simple change below for now? IIRC 32-bit task can't use > > "syscall" so if syscall_get_nr() >= 0 then even the wrong TS_COMPAT is > > not that bad, even if it "leaks" to user-mode. > > Hmm. That should fix the minor security issue, but it will even > further break cross-arch tracing: now a 32-bit tracer tracing a 64-bit > task that does int $0x80 will malfunction even more than it would > have.
This is broken in any case. I mean, a 32-bit debugger can't really debug a 64-bit task. I don't think this change makes the things really worse. > Also, it relies on bizarre arch details IMO. Heh, it looks as if your patch do not ;) > I think I prefer my version, coming momentarily. I disagree... I don't really understand why do we need the additional complications for the minimal fix which doesn't look very nice anyway. But I won't argue, and your patch looks correct to me. Oleg.
