diff options
Diffstat (limited to 'pkg/sentry/platform/ring0')
| -rw-r--r-- | pkg/sentry/platform/ring0/kernel_amd64.go | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/pkg/sentry/platform/ring0/kernel_amd64.go b/pkg/sentry/platform/ring0/kernel_amd64.go index c828af654..117e86104 100644 --- a/pkg/sentry/platform/ring0/kernel_amd64.go +++ b/pkg/sentry/platform/ring0/kernel_amd64.go @@ -162,17 +162,16 @@ func IsCanonical(addr uint64) bool { // code that uses IP-relative addressing inside of absolute addresses. That's // the case for amd64, but may not be the case for other architectures. // +// Precondition: the Rip, Rsp, Fs and Gs registers must be canonical. + +// //go:nosplit func (c *CPU) SwitchToUser(switchOpts SwitchOpts) (vector Vector) { - // Check for canonical addresses. - regs := switchOpts.Registers - if !IsCanonical(regs.Rip) || !IsCanonical(regs.Rsp) || !IsCanonical(regs.Fs_base) || !IsCanonical(regs.Gs_base) { - return GeneralProtectionFault - } userCR3 := switchOpts.PageTables.CR3(!switchOpts.Flush, switchOpts.UserPCID) kernelCR3 := c.kernel.PageTables.CR3(true, switchOpts.KernelPCID) // Sanitize registers. + regs := switchOpts.Registers regs.Eflags &= ^uint64(UserFlagsClear) regs.Eflags |= UserFlagsSet regs.Cs = uint64(Ucode64) // Required for iret. |