On Sun, Apr 08, 2018 at 08:40:10PM -0700, Alexei Starovoitov wrote: > On Sun, Apr 08, 2018 at 04:07:42PM +0800, joeyli wrote: > > > > > If the only thing that folks are paranoid about is reading > > > arbitrary kernel memory with bpf_probe_read() helper > > > then preferred patch would be to disable it during verification > > > when in lockdown mode > > > > Sorry for I didn't fully understand your idea... > > Do you mean that using bpf verifier to filter out bpf program that > > uses bpf_probe_read()? > > Take a look bpf_get_trace_printk_proto(). > Similarly we can add bpf_get_probe_read_proto() that > will return NULL if lockdown is on. > Then programs with bpf_probe_read() will be rejected by the verifier. > OK, I saw check_helper_call(). Thank you for point it out. it's good idea! Joey Lee -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
