Sigh. That capability really is fscked up. Matthew Garrett <matthew.garrett@xxxxxxxxxx> wrote: >On Wed, 2013-09-04 at 20:52 -0700, H. Peter Anvin wrote: >> On 09/03/2013 04:50 PM, Matthew Garrett wrote: >> > IO port access would permit users to gain access to PCI >configuration >> > registers, which in turn (on a lot of hardware) give access to MMIO >register >> > space. This would potentially permit root to trigger arbitrary DMA, >so lock >> > it down by default. >> > >> > Signed-off-by: Matthew Garrett <matthew.garrett@xxxxxxxxxx> >> >> Seriously... just deny CAP_SYS_RAWIO to any system in secure mode. > >No. CAP_SYS_RAWIO blocks things that we don't want blocked (x86 >microcode updates, various disk ioctls, *device firmware uploads* and a >few others) - the semantics just don't match. We could relax those >permissions, but then we'd potentially break someone else's security >considerations. -- Sent from my mobile phone. Please pardon brevity and lack of formatting. -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
