diff --git a/Lib/test/test_codecs.py b/Lib/test/test_codecs.py index 93660f7a198..f2a1ae3f790 100644 --- a/Lib/test/test_codecs.py +++ b/Lib/test/test_codecs.py @@ -668,6 +668,8 @@ class UTF8Test(ReadTest): self.assertTrue(codecs.lookup_error("surrogatepass")) with self.assertRaises(UnicodeDecodeError): b"abc\xed\xa0".decode("utf-8", "surrogatepass") + with self.assertRaises(UnicodeDecodeError): + b"abc\xed\xa0z".decode("utf-8", "surrogatepass") @unittest.skipUnless(sys.platform == 'win32', 'cp65001 is a Windows-only codec') diff --git a/Misc/NEWS b/Misc/NEWS index 9b27caf00eb..16741cd4058 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -10,6 +10,9 @@ What's New in Python 3.4.0 Alpha 1? Core and Builtins ----------------- +- Issue #16336: fix input checking in the surrogatepass error handler. + Patch by Serhiy Storchaka. + - Issue #8401: assigning an int to a bytearray slice (e.g. b[3:4] = 5) now raises an error. diff --git a/Python/codecs.c b/Python/codecs.c index 5cfb1c90014..37ae41b1ca4 100644 --- a/Python/codecs.c +++ b/Python/codecs.c @@ -791,10 +791,10 @@ PyCodec_SurrogatePassErrors(PyObject *exc) /* Try decoding a single surrogate character. If there are more, let the codec call us again. */ p += start; - if (strlen(p) > 2 && - ((p[0] & 0xf0) == 0xe0 || - (p[1] & 0xc0) == 0x80 || - (p[2] & 0xc0) == 0x80)) { + if (PyBytes_GET_SIZE(object) - start >= 3 && + (p[0] & 0xf0) == 0xe0 && + (p[1] & 0xc0) == 0x80 && + (p[2] & 0xc0) == 0x80) { /* it's a three-byte code */ ch = ((p[0] & 0x0f) << 12) + ((p[1] & 0x3f) << 6) + (p[2] & 0x3f); if (!Py_UNICODE_IS_SURROGATE(ch))