Make KillFilter to handle 'deleted' w/o rstrip.

The initial code for this fixed used rstrip incorrectly.
This implementation uses endswith and rindex instead
and should read a bit more easily.

Also added a unit test to test that 'deleted' exe's are
filtered correctly.

Fixes LP Bug #967931.

Change-Id: I1783a8e2d59edd35734673b23e295f5a0b80b988

nova/rootwrap/filters.py

@@ -119,7 +119,8 @@ class KillFilter(CommandFilter):
             command = os.readlink("/proc/%d/exe" % int(args[1]))
             # NOTE(dprince): /proc/PID/exe may have ' (deleted)' on
             # the end if an executable is updated or deleted
-            command = command.rstrip(" (deleted)")
+            if command.endswith(" (deleted)"):
+                command = command[:command.rindex(" ")]
             if command not in self.args[1]:
                 # Affected executable not in accepted list
                 return False

nova/tests/test_nova_rootwrap.py

@@ -103,6 +103,20 @@ class RootwrapTestCase(test.TestCase):
         usercmd = ['kill', 'notapid']
         self.assertFalse(f.match(usercmd))
 
+    def test_KillFilter_deleted_exe(self):
+        """Makes sure deleted exe's are killed correctly"""
+        # See bug #967931.
+        def fake_readlink(blah):
+            return '/bin/commandddddd (deleted)'
+
+        f = filters.KillFilter("/bin/kill", "root",
+                               [""],
+                               ["/bin/commandddddd"])
+        usercmd = ['kill', 1234]
+        # Providing no signal should work
+        self.stubs.Set(os, 'readlink', fake_readlink)
+        self.assertTrue(f.match(usercmd))
+
     def test_ReadFileFilter(self):
         goodfn = '/good/file.name'
         f = filters.ReadFileFilter(goodfn)