src/encoding/json/decode.go      |  5 +++++
 src/encoding/json/decode_test.go | 33 +++++++++++++++++++++++++++++++--

diff --git a/src/encoding/json/decode.go b/src/encoding/json/decode.go
index b43484692e18565d453fa7c8b364435bf7e56803..b60e2bb0b2c4dbee63f3a4d7e59c7cb03550abe3 100644
--- a/src/encoding/json/decode.go
+++ b/src/encoding/json/decode.go
@@ -1217,6 +1217,11 @@ 	r := d.safeUnquote
 	if r == -1 {
 		return s, true
 	}
+	// Only perform up to one safe unquote for each re-scanned string
+	// literal. In some edge cases, the decoder unquotes a literal a second
+	// time, even after another literal has been re-scanned. Thus, only the
+	// first unquote can safely use safeUnquote.
+	d.safeUnquote = 0
 
 	b := make([]byte, len(s)+2*utf8.UTFMax)
 	w := copy(b, s[0:r])
diff --git a/src/encoding/json/decode_test.go b/src/encoding/json/decode_test.go
index 498bd97b46ef41dc9a2ceba27d449be428fc6d30..a49181e9823d378e1eac372281722981678e3ad7 100644
--- a/src/encoding/json/decode_test.go
+++ b/src/encoding/json/decode_test.go
@@ -2419,7 +2419,7 @@ 	*m = textUnmarshalerString(strings.ToLower(string(text)))
 	return nil
 }
 
-// Test unmarshal to a map, with map key is a user defined type.
+// Test unmarshal to a map, where the map key is a user defined type.
 // See golang.org/issues/34437.
 func TestUnmarshalMapWithTextUnmarshalerStringKey(t *testing.T) {
 	var p map[textUnmarshalerString]string
@@ -2428,6 +2428,35 @@ 		t.Fatalf("Unmarshal unexpected error: %v", err)
 	}
 
 	if _, ok := p["foo"]; !ok {
-		t.Errorf(`Key "foo" is not existed in map: %v`, p)
+		t.Errorf(`Key "foo" does not exist in map: %v`, p)
+	}
+}
+
+func TestUnmarshalRescanLiteralMangledUnquote(t *testing.T) {
+	// See golang.org/issues/38105.
+	var p map[textUnmarshalerString]string
+	if err := Unmarshal([]byte(`{"开源":"12345开源"}`), &p); err != nil {
+		t.Fatalf("Unmarshal unexpected error: %v", err)
+	}
+	if _, ok := p["开源"]; !ok {
+		t.Errorf(`Key "开源" does not exist in map: %v`, p)
+	}
+
+	// See golang.org/issues/38126.
+	type T struct {
+		F1 string `json:"F1,string"`
+	}
+	t1 := T{"aaa\tbbb"}
+
+	b, err := Marshal(t1)
+	if err != nil {
+		t.Fatalf("Marshal unexpected error: %v", err)
+	}
+	var t2 T
+	if err := Unmarshal(b, &t2); err != nil {
+		t.Fatalf("Unmarshal unexpected error: %v", err)
+	}
+	if t1 != t2 {
+		t.Errorf("Marshal and Unmarshal roundtrip mismatch: want %q got %q", t1, t2)
 	}
 }