Routing: in a dnslookup, fix fail_defer_domains to defer on missing MX record. Bug 1867

2 files changed, 17 insertions, 17 deletions

diff --git a/src/src/routers/dnslookup.c b/src/src/routers/dnslookup.c
index 83ba5f689..d2be40e0f 100644
--- a/src/src/routers/dnslookup.c
+++ b/src/src/routers/dnslookup.c
@@ -305,6 +305,22 @@ for (;;)
 
   if (rc != HOST_FIND_FAILED) break;
 
+  if (ob->fail_defer_domains)
+    switch(match_isinlist(fully_qualified_name,
+	  CUSS &ob->fail_defer_domains, 0,
+	  &domainlist_anchor, addr->domain_cache, MCL_DOMAIN, TRUE, NULL))
+      {
+      case DEFER:
+	addr->message = US"lookup defer for fail_defer_domains option";
+	return DEFER;
+
+      case OK:
+	DEBUG(D_route) debug_printf("%s router: matched fail_defer_domains\n",
+	  rblock->name);
+	addr->message = US"missing MX, or all MXs point to missing A records,"
+	  " and defer requested";
+	return DEFER;
+      }
   /* Check to see if the failure is the result of MX records pointing to
   non-existent domains, and if so, set an appropriate error message; the case
   of an MX or SRV record pointing to "." is another special case that we can
@@ -335,22 +351,6 @@ for (;;)
           addr->message);
         }
       }
-    if (ob->fail_defer_domains)
-      {
-      switch(match_isinlist(fully_qualified_name,
-	    CUSS &ob->fail_defer_domains, 0,
-	    &domainlist_anchor, addr->domain_cache, MCL_DOMAIN, TRUE, NULL))
-	{
-	case DEFER:
-	  addr->message = US"lookup defer for fail_defer_domains";
-	  return DEFER;
-
-	case OK:
-	  DEBUG(D_route) debug_printf("%s router: matched fail_defer_domains\n",
-	    rblock->name);
-	  return DEFER;
-	}
-      }
     return DECLINE;
     }
 
diff --git a/src/src/utf8.c b/src/src/utf8.c
index 84ad1dc18..e394db0a8 100644
--- a/src/src/utf8.c
+++ b/src/src/utf8.c
@@ -18,7 +18,7 @@ BOOL
 string_is_utf8(const uschar * s)
 {
 uschar c;
-while ((c = *s++)) if (c & 0x80) return TRUE;
+if (s) while ((c = *s++)) if (c & 0x80) return TRUE;
 return FALSE;
 }