Merge branch '2018.3' into network_dns_check_test

salt/utils/process.py

@@ -806,7 +806,7 @@ def default_signals(*signals):
     old_signals = {}
     for signum in signals:
         try:
-            old_signals[signum] = signal.getsignal(signum)
+            saved_signal = signal.getsignal(signum)
             signal.signal(signum, signal.SIG_DFL)
         except ValueError as exc:
             # This happens when a netapi module attempts to run a function
@@ -816,6 +816,8 @@ def default_signals(*signals):
                 'Failed to register signal for signum %d: %s',
                 signum, exc
             )
+        else:
+            old_signals[signum] = saved_signal
 
     # Do whatever is needed with the reset signals
     yield