2 ms·
That issue can be dealt with using an IOMMU under host control. Those limit where the peripheral can DMA regardless of its firmware.
by jlokier 3y ago
That issue can be dealt with using an IOMMU under host control. Those limit where the peripheral can DMA regardless of its firmware.
- isopede 3y agoIsn't this just an instance of "trusting trust?" How do you know the IOMMU hasn't been backdoored? "Open" firmware doesn't mean open RTL. Where is the line drawn?
- Dylan16807 3y agoWhether you want open firmware in the first place is a significantly different question from how you isolate hardware with closed firmware. But more directly, worrying about one part having a backdoor is a lot better than worrying about twenty parts having a backdoor.
- saagarjha 3y agoJust an example, DARTs and IOMMUs help close down that line of attack but there are still many proprietary and inscrutable blobs/peripherals/monitors that alter the behavior of modern computers which are almost impossible to avoid in general.