Resolve issue 3321: (segfault) _multiprocessing.Connection() doesn't check handle

jesse.noller · jesse.noller · commit dbbd6d228b9f · 2009-01-19T15:12:22.000Z
git-svn-id: http://svn.python.org/projects/python/trunk@68768 6015fed2-1504-0410-9fe1-9d1591cc4771
diff --git a/Lib/test/test_multiprocessing.py b/Lib/test/test_multiprocessing.py
@@ -61,6 +61,8 @@
 HAVE_GETVALUE = not getattr(_multiprocessing,
                             'HAVE_BROKEN_SEM_GETVALUE', False)
 
+WIN32 = (sys.platform == "win32")
+
 #
 # Creates a wrapper for a function which records the time it takes to finish
 #
@@ -1682,6 +1684,18 @@ def test_level(self):
         logger.setLevel(level=LOG_LEVEL)
 
 #
+# Test to verify handle verification, see issue 3321
+#
+
+class TestInvalidHandle(unittest.TestCase):
+
+    def test_invalid_handles(self):
+        if WIN32:
+            return
+        conn = _multiprocessing.Connection(44977608)
+        self.assertRaises(IOError, conn.poll)
+        self.assertRaises(IOError, _multiprocessing.Connection, -1)
+#
 # Functions used to create test cases from the base ones in this module
 #
 
@@ -1785,7 +1799,7 @@ def send_bytes(self, data):
                           multiprocessing.connection.answer_challenge,
                           _FakeConnection(), b'abc')
 
-testcases_other = [OtherTest]
+testcases_other = [OtherTest, TestInvalidHandle]
 
 #
 #
diff --git a/Misc/NEWS b/Misc/NEWS
@@ -140,6 +140,10 @@ Core and Builtins
 Library
 -------
 
+- Issue #3321: _multiprocessing.Connection() doesn't check handle; added checks
+  for *nix machines for negative handles and large int handles. Without this check
+  it is possible to segfault the interpreter.
+
 - Issue #4449: AssertionError in mp_benchmarks.py, caused by an underlying issue
   in sharedctypes.py.
 
diff --git a/Modules/_multiprocessing/connection.h b/Modules/_multiprocessing/connection.h
@@ -354,7 +354,7 @@ connection_poll(ConnectionObject *self, PyObject *args)
 	}
 
 	Py_BEGIN_ALLOW_THREADS
-	res = conn_poll(self, timeout);
+	res = conn_poll(self, timeout, _save);
 	Py_END_ALLOW_THREADS
 
 	switch (res) {
diff --git a/Modules/_multiprocessing/socket_connection.c b/Modules/_multiprocessing/socket_connection.c
@@ -153,11 +153,23 @@ conn_recv_string(ConnectionObject *conn, char *buffer,
  */
 
 static int
-conn_poll(ConnectionObject *conn, double timeout)
+conn_poll(ConnectionObject *conn, double timeout, PyThreadState *_save)
 {
 	int res;
 	fd_set rfds;
 
+	/*
+	 * Verify the handle, issue 3321. Not required for windows.
+	 */ 
+	#ifndef MS_WINDOWS
+		if (((int)conn->handle) < 0 || ((int)conn->handle) >= FD_SETSIZE) {
+			Py_BLOCK_THREADS
+			PyErr_SetString(PyExc_IOError, "handle out of range in select()");
+			Py_UNBLOCK_THREADS
+			return MP_EXCEPTION_HAS_BEEN_SET;
+		}
+	#endif
+
 	FD_ZERO(&rfds);
 	FD_SET((SOCKET)conn->handle, &rfds);
 

Original file line number	Diff line number	Diff line change
`@@ -61,6 +61,8 @@`
`61`	`61`	`HAVE_GETVALUE = not getattr(_multiprocessing,`
`62`	`62`	`'HAVE_BROKEN_SEM_GETVALUE', False)`
`63`	`63`
	`64`	`+WIN32 = (sys.platform == "win32")`
	`65`	`+`
`64`	`66`	`#`
`65`	`67`	`# Creates a wrapper for a function which records the time it takes to finish`
`66`	`68`	`#`
`@@ -1682,6 +1684,18 @@ def test_level(self):`
`1682`	`1684`	`logger.setLevel(level=LOG_LEVEL)`
`1683`	`1685`
`1684`	`1686`	`#`
	`1687`	`+# Test to verify handle verification, see issue 3321`
	`1688`	`+#`
	`1689`	`+`
	`1690`	`+class TestInvalidHandle(unittest.TestCase):`
	`1691`	`+`
	`1692`	`+ def test_invalid_handles(self):`
	`1693`	`+ if WIN32:`
	`1694`	`+ return`
	`1695`	`+ conn = _multiprocessing.Connection(44977608)`
	`1696`	`+ self.assertRaises(IOError, conn.poll)`
	`1697`	`+ self.assertRaises(IOError, _multiprocessing.Connection, -1)`
	`1698`	`+#`
`1685`	`1699`	`# Functions used to create test cases from the base ones in this module`
`1686`	`1700`	`#`
`1687`	`1701`
`@@ -1785,7 +1799,7 @@ def send_bytes(self, data):`
`1785`	`1799`	`multiprocessing.connection.answer_challenge,`
`1786`	`1800`	`_FakeConnection(), b'abc')`
`1787`	`1801`
`1788`		`-testcases_other = [OtherTest]`
	`1802`	`+testcases_other = [OtherTest, TestInvalidHandle]`
`1789`	`1803`
`1790`	`1804`	`#`
`1791`	`1805`	`#`
Original file line number	Diff line number	Diff line change
`@@ -354,7 +354,7 @@ connection_poll(ConnectionObject self, PyObject args)`
`354`	`354`	`}`
`355`	`355`
`356`	`356`	`Py_BEGIN_ALLOW_THREADS`
`357`		`- res = conn_poll(self, timeout);`
	`357`	`+ res = conn_poll(self, timeout, _save);`
`358`	`358`	`Py_END_ALLOW_THREADS`
`359`	`359`
`360`	`360`	`switch (res) {`