diff options
Diffstat (limited to 'pkg')
| -rw-r--r-- | pkg/sentry/platform/ring0/kernel_amd64.go | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/pkg/sentry/platform/ring0/kernel_amd64.go b/pkg/sentry/platform/ring0/kernel_amd64.go index 3577b5127..0feff8778 100644 --- a/pkg/sentry/platform/ring0/kernel_amd64.go +++ b/pkg/sentry/platform/ring0/kernel_amd64.go @@ -70,6 +70,14 @@ func (c *CPU) init() { c.tss.ist1Lo = uint32(stackAddr) c.tss.ist1Hi = uint32(stackAddr >> 32) + // Set the I/O bitmap base address beyond the last byte in the TSS + // to block access to the entire I/O address range. + // + // From section 18.5.2 "I/O Permission Bit Map" from Intel SDM vol1: + // I/O addresses not spanned by the map are treated as if they had set + // bits in the map. + c.tss.ioPerm = tssLimit + 1 + // Permanently set the kernel segments. c.registers.Cs = uint64(Kcode) c.registers.Ds = uint64(Kdata) |