Merge pull request #1978 from lubinszARM:pr_signal_mm

PiperOrigin-RevId: 307078788

pkg/sentry/mm/lifecycle.go

@@ -84,6 +84,7 @@ func (mm *MemoryManager) Fork(ctx context.Context) (*MemoryManager, error) {
 		dumpability:        mm.dumpability,
 		aioManager:         aioManager{contexts: make(map[uint64]*AIOContext)},
 		sleepForActivation: mm.sleepForActivation,
+		vdsoSigReturnAddr:  mm.vdsoSigReturnAddr,
 	}
 
 	// Copy vmas.

pkg/sentry/mm/metadata.go

@@ -167,3 +167,17 @@ func (mm *MemoryManager) SetExecutable(file fsbridge.File) {
 		orig.DecRef()
 	}
 }
+
+// VDSOSigReturn returns the address of vdso_sigreturn.
+func (mm *MemoryManager) VDSOSigReturn() uint64 {
+	mm.metadataMu.Lock()
+	defer mm.metadataMu.Unlock()
+	return mm.vdsoSigReturnAddr
+}
+
+// SetVDSOSigReturn sets the address of vdso_sigreturn.
+func (mm *MemoryManager) SetVDSOSigReturn(addr uint64) {
+	mm.metadataMu.Lock()
+	defer mm.metadataMu.Unlock()
+	mm.vdsoSigReturnAddr = addr
+}

pkg/sentry/mm/mm.go

@@ -231,6 +231,9 @@ type MemoryManager struct {
 	// before trying to activate the address space. When set to true, delays in
 	// activation are not reported as stuck tasks by the watchdog.
 	sleepForActivation bool
+
+	// vdsoSigReturnAddr is the address of 'vdso_sigreturn'.
+	vdsoSigReturnAddr uint64
 }
 
 // vma represents a virtual memory area.