diff --git a/src/runtime/slice.go b/src/runtime/slice.go
index cfa862e047..66bb7d9d93 100644
--- a/src/runtime/slice.go
+++ b/src/runtime/slice.go
@@ -124,7 +124,7 @@ func unsafeslice(et *_type, ptr unsafe.Pointer, len int) {
 	}
 
 	mem, overflow := math.MulUintptr(et.size, uintptr(len))
-	if overflow || mem > maxAlloc || len < 0 {
+	if overflow || mem > -uintptr(ptr) || len < 0 {
 		panicunsafeslicelen()
 	}
 }
diff --git a/test/unsafebuiltins.go b/test/unsafebuiltins.go
index 4c940aa855..d04bcbdc7d 100644
--- a/test/unsafebuiltins.go
+++ b/test/unsafebuiltins.go
@@ -47,6 +47,11 @@ func main() {
 		// size overflows address space
 		mustPanic(func() { _ = unsafe.Slice(new(uint64), maxUintptr/8) })
 		mustPanic(func() { _ = unsafe.Slice(new(uint64), maxUintptr/8+1) })
+
+		// sliced memory overflows address space
+		last := (*byte)(unsafe.Pointer(^uintptr(0)))
+		_ = unsafe.Slice(last, 1)
+		mustPanic(func() { _ = unsafe.Slice(last, 2) })
 	}
 }