1 files changed, 36 insertions, 1 deletions
diff --git a/pkg/sentry/platform/ptrace/subprocess_arm64.go b/pkg/sentry/platform/ptrace/subprocess_arm64.go
index bec884ba5..aed34e7ee 100644
--- a/pkg/sentry/platform/ptrace/subprocess_arm64.go
+++ b/pkg/sentry/platform/ptrace/subprocess_arm64.go
@@ -17,8 +17,12 @@
 package ptrace
 
 import (
+	"fmt"
+	"strings"
 	"syscall"
 
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/seccomp"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 )
 
@@ -37,7 +41,7 @@ const (
 // resetSysemuRegs sets up emulation registers.
 //
 // This should be called prior to calling sysemu.
-func (s *subprocess) resetSysemuRegs(regs *syscall.PtraceRegs) {
+func (t *thread) resetSysemuRegs(regs *syscall.PtraceRegs) {
 }
 
 // createSyscallRegs sets up syscall registers.
@@ -124,3 +128,34 @@ func (t *thread) adjustInitRegsRip() {
 func initChildProcessPPID(initregs *syscall.PtraceRegs, ppid int32) {
 	initregs.Regs[7] = uint64(ppid)
 }
+
+// patchSignalInfo patches the signal info to account for hitting the seccomp
+// filters from vsyscall emulation, specified below. We allow for SIGSYS as a
+// synchronous trap, but patch the structure to appear like a SIGSEGV with the
+// Rip as the faulting address.
+//
+// Note that this should only be called after verifying that the signalInfo has
+// been generated by the kernel.
+func patchSignalInfo(regs *syscall.PtraceRegs, signalInfo *arch.SignalInfo) {
+	if linux.Signal(signalInfo.Signo) == linux.SIGSYS {
+		signalInfo.Signo = int32(linux.SIGSEGV)
+
+		// Unwind the kernel emulation, if any has occurred. A SIGSYS is delivered
+		// with the si_call_addr field pointing to the current RIP. This field
+		// aligns with the si_addr field for a SIGSEGV, so we don't need to touch
+		// anything there. We do need to unwind emulation however, so we set the
+		// instruction pointer to the faulting value, and "unpop" the stack.
+		regs.Pc = signalInfo.Addr()
+		regs.Sp -= 8
+	}
+}
+
+// Noop on arm64.
+func enableCpuidFault() {
+}
+
+// appendArchSeccompRules append architecture specific seccomp rules when creating BPF program.
+// Ref attachedThread() for more detail.
+func appendArchSeccompRules(rules []seccomp.RuleSet) []seccomp.RuleSet {
+	return rules
+}