Fix panic in EscapeReader (#18820) There is a potential panic due to a mistaken resetting of the length parameter when multibyte characters go over a read boundary. Signed-off-by: Andrew Thornton <art27@cantab.net>

Changes

2 changed files (+10/-0)

• modules/charset/escape.go
  • @@ -74,6 +74,7 @@ readingloop:
    for err == nil { n, err = text.Read(buf[readStart:]) bs := buf[:n+readStart] + n = len(bs) i := 0 for i < len(bs) {
• modules/charset/escape_test.go
  • @@ -200,3 +200,12 @@ func TestEscapeControlReader(t *testing.T) {
    }) } } + + func TestEscapeControlReader_panic(t *testing.T) { + bs := make([]byte, 0, 20479) + bs = append(bs, 'A') + for i := 0; i < 6826; i++ { + bs = append(bs, []byte("—")...) + } + _, _ = EscapeControlBytes(bs) + }