Issue #26644: Raise ValueError for negative SSLSocket.recv() and read()

Lib/test/test_ssl.py

@@ -2792,6 +2792,13 @@ else:
                         # consume data
                         s.read()
 
+                # read(-1, buffer) is supported, even though read(-1) is not
+                data = b"data"
+                s.send(data)
+                buffer = bytearray(len(data))
+                self.assertEqual(s.read(-1, buffer), len(data))
+                self.assertEqual(buffer, data)
+
                 # Make sure sendmsg et al are disallowed to avoid
                 # inadvertent disclosure of data and/or corruption
                 # of the encrypted data stream
@@ -2801,6 +2808,10 @@ else:
                                   s.recvmsg_into, bytearray(100))
 
                 s.write(b"over\n")
+
+                self.assertRaises(ValueError, s.recv, -1)
+                self.assertRaises(ValueError, s.read, -1)
+
                 s.close()
 
         def test_nonblocking_send(self):

Misc/NEWS

@@ -94,6 +94,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #26644: Raise ValueError rather than SystemError when a negative
+  length is passed to SSLSocket.recv() or read().
+
 - Issue #26616: Fixed a bug in datetime.astimezone() method.
 
 - Issue #21925: :func:`warnings.formatwarning` now catches exceptions on

Modules/_ssl.c

@@ -1895,6 +1895,11 @@ _ssl__SSLSocket_read_impl(PySSLSocket *self, int len, int group_right_1,
     _PyTime_t timeout, deadline = 0;
     int has_timeout;
 
+    if (!group_right_1 && len < 0) {
+        PyErr_SetString(PyExc_ValueError, "size should not be negative");
+        return NULL;
+    }
+
     if (sock != NULL) {
         if (((PyObject*)sock) == Py_None) {
             _setSSLError("Underlying socket connection gone",