On Thu, Nov 08, 2012 at 10:40:33AM +0100, Thomas Renninger wrote: > On Wednesday, November 07, 2012 09:54:03 PM Matthew Garrett wrote: > > Is there a case where modifying MSRs or EC registers can cause arbitrary > > code execution? > > Ok, I am not familiar enough with this secure stuff. > Theoretically writing EC registers could be used to trick ACPI > code and change the way it is processed by inspecting ACPI > code for bad EC register return values. I'd prefer to see an actual example before worrying too much about this. > Similar for MSR, the kernel could be (not directly) influenced > by setting MSR registers in a way it does not expect them to be. Again, I'd like to see an example of arbitrary code execution. > I expect it's easy to get the system totally stalled/hang/rebooted > with bad MSR writes which I thought should be forbidden for > userspace (even for root...) in secure boot mode. root can call halt, which is a trivial DoS. It's not worth worrying about people wedging the system. -- Matthew Garrett | mjg59@xxxxxxxxxxxxx -- 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