diff options
Diffstat (limited to 'pkg/sentry/platform/kvm')
| -rw-r--r-- | pkg/sentry/platform/kvm/bluepill.go | 13 | ||||
| -rw-r--r-- | pkg/sentry/platform/kvm/bluepill_arm64.s | 12 | ||||
| -rw-r--r-- | pkg/sentry/platform/kvm/bluepill_impl_amd64.s | 12 |
3 files changed, 34 insertions, 3 deletions
diff --git a/pkg/sentry/platform/kvm/bluepill.go b/pkg/sentry/platform/kvm/bluepill.go index fd1131638..bb9967b9f 100644 --- a/pkg/sentry/platform/kvm/bluepill.go +++ b/pkg/sentry/platform/kvm/bluepill.go @@ -16,7 +16,6 @@ package kvm import ( "fmt" - "reflect" "golang.org/x/sys/unix" "gvisor.dev/gvisor/pkg/ring0" @@ -36,6 +35,14 @@ func sighandler() // dieArchSetup and the assembly implementation for dieTrampoline. func dieTrampoline() +// Return the start address of the functions above. +// +// In Go 1.17+, Go references to assembly functions resolve to an ABIInternal +// wrapper function rather than the function itself. We must reference from +// assembly to get the ABI0 (i.e., primary) address. +func addrOfSighandler() uintptr +func addrOfDieTrampoline() uintptr + var ( // bounceSignal is the signal used for bouncing KVM. // @@ -87,10 +94,10 @@ func (c *vCPU) die(context *arch.SignalContext64, msg string) { func init() { // Install the handler. - if err := safecopy.ReplaceSignalHandler(bluepillSignal, reflect.ValueOf(sighandler).Pointer(), &savedHandler); err != nil { + if err := safecopy.ReplaceSignalHandler(bluepillSignal, addrOfSighandler(), &savedHandler); err != nil { panic(fmt.Sprintf("Unable to set handler for signal %d: %v", bluepillSignal, err)) } // Extract the address for the trampoline. - dieTrampolineAddr = reflect.ValueOf(dieTrampoline).Pointer() + dieTrampolineAddr = addrOfDieTrampoline() } diff --git a/pkg/sentry/platform/kvm/bluepill_arm64.s b/pkg/sentry/platform/kvm/bluepill_arm64.s index 09c7e88e5..308f2a951 100644 --- a/pkg/sentry/platform/kvm/bluepill_arm64.s +++ b/pkg/sentry/platform/kvm/bluepill_arm64.s @@ -92,6 +92,12 @@ fallback: MOVD ·savedHandler(SB), R7 B (R7) +// func addrOfSighandler() uintptr +TEXT ·addrOfSighandler(SB), $0-8 + MOVD $·sighandler(SB), R0 + MOVD R0, ret+0(FP) + RET + // dieTrampoline: see bluepill.go, bluepill_arm64_unsafe.go for documentation. TEXT ·dieTrampoline(SB),NOSPLIT,$0 // R0: Fake the old PC as caller @@ -99,3 +105,9 @@ TEXT ·dieTrampoline(SB),NOSPLIT,$0 MOVD.P R1, 8(RSP) // R1: First argument (vCPU) MOVD.P R0, 8(RSP) // R0: Fake the old PC as caller B ·dieHandler(SB) + +// func addrOfDieTrampoline() uintptr +TEXT ·addrOfDieTrampoline(SB), $0-8 + MOVD $·dieTrampoline(SB), R0 + MOVD R0, ret+0(FP) + RET diff --git a/pkg/sentry/platform/kvm/bluepill_impl_amd64.s b/pkg/sentry/platform/kvm/bluepill_impl_amd64.s index 2bbf06b18..b7f1dd5ac 100644 --- a/pkg/sentry/platform/kvm/bluepill_impl_amd64.s +++ b/pkg/sentry/platform/kvm/bluepill_impl_amd64.s @@ -151,8 +151,20 @@ fallback: MOVQ ·savedHandler(SB), AX JMP AX +// func addrOfSighandler() uintptr +TEXT ·addrOfSighandler(SB), $0-8 + MOVQ $·sighandler(SB), AX + MOVQ AX, ret+0(FP) + RET + // dieTrampoline: see bluepill.go, bluepill_amd64_unsafe.go for documentation. TEXT ·dieTrampoline(SB),NOSPLIT,$0 PUSHQ BX // First argument (vCPU). PUSHQ AX // Fake the old RIP as caller. JMP ·dieHandler(SB) + +// func addrOfDieTrampoline() uintptr +TEXT ·addrOfDieTrampoline(SB), $0-8 + MOVQ $·dieTrampoline(SB), AX + MOVQ AX, ret+0(FP) + RET |