diff --git a/src/database/sql/convert.go b/src/database/sql/convert.go
index 92c3b689c1..99aed2398e 100644
--- a/src/database/sql/convert.go
+++ b/src/database/sql/convert.go
@@ -217,7 +217,12 @@ func convertAssign(dest, src interface{}) error {
 
 	dv := reflect.Indirect(dpv)
 	if sv.IsValid() && sv.Type().AssignableTo(dv.Type()) {
-		dv.Set(sv)
+		switch b := src.(type) {
+		case []byte:
+			dv.Set(reflect.ValueOf(cloneBytes(b)))
+		default:
+			dv.Set(sv)
+		}
 		return nil
 	}
 
diff --git a/src/database/sql/convert_test.go b/src/database/sql/convert_test.go
index 342875e190..ab81f2f65a 100644
--- a/src/database/sql/convert_test.go
+++ b/src/database/sql/convert_test.go
@@ -377,3 +377,15 @@ func TestRawBytesAllocs(t *testing.T) {
 		t.Fatalf("allocs = %v; want max 1", n)
 	}
 }
+
+// https://github.com/golang/go/issues/13905
+func TestUserDefinedBytes(t *testing.T) {
+	type userDefinedBytes []byte
+	var u userDefinedBytes
+	v := []byte("foo")
+
+	convertAssign(&u, v)
+	if &u[0] == &v[0] {
+		t.Fatal("userDefinedBytes got potentially dirty driver memory")
+	}
+}