Merge lp:~lamont/maas/bug-1655049 into lp:~maas-committers/maas/trunk

[LaMont Jones]

Protect get_vendor_for_mac() against IndexError.

Bug#1628761 can also result in IndexError being raised by netaddr.EUI().oui.registration().

[Mike Pontillo (mpontillo)]

This is unfortunate, but it looks good. Thanks for the fix.

We should probably raise this upstream.

review: Approve

=== modified file 'src/maasserver/utils/mac.py'
--- src/maasserver/utils/mac.py	2016-06-22 17:03:02 +0000
+++ src/maasserver/utils/mac.py	2017-01-09 17:01:09 +0000
@@ -18,7 +18,9 @@
     data = EUI(mac)
     try:
         return data.oui.registration().org
-    except (NotRegisteredError, UnicodeDecodeError):
+    except (IndexError, NotRegisteredError, UnicodeDecodeError):
+        # Bug#1655049: IndexError is raised for some unicode strings.  See also
+        # Bug#1628761.
         # UnicodeDecodeError can be raised if the name of the vendor cannot
         # be decoded from ascii. This is something broken in the netaddr
         # library, we are just catching the error here not to break the UI.

=== modified file 'src/maasserver/utils/tests/test_mac.py'
--- src/maasserver/utils/tests/test_mac.py	2016-12-07 12:46:14 +0000
+++ src/maasserver/utils/tests/test_mac.py	2017-01-09 17:01:09 +0000
@@ -37,3 +37,16 @@
         self.assertEqual(
             "Unknown Vendor",
             get_vendor_for_mac(factory.make_mac_address()))
+
+    def test_get_vendor_survives_index_error(self):
+        try:
+            arr = []
+            arr[3]
+        except IndexError as exc:
+            error = exc
+        eui_result = MagicMock()
+        eui_result.oui.registration.side_effect = error
+        self.patch(mac, "EUI").return_value = eui_result
+        self.assertEqual(
+            "Unknown Vendor",
+            get_vendor_for_mac(factory.make_mac_address()))