Bug 593170: Disallow urls like "show_bug.cgi?id=2323" (with no domain) in

Bugzilla/Bug.pm

@@ -2815,6 +2815,15 @@ sub add_see_also {
         ThrowUserError('bug_url_invalid', { url => $input, reason => 'http' });
     }
 
+    # This stops the following edge cases from being accepted:
+    # * show_bug.cgi?id=1
+    # * /show_bug.cgi?id=1
+    # * http:///show_bug.cgi?id=1
+    if (!$uri->authority or $uri->path !~ m{/}) {
+        ThrowUserError('bug_url_invalid',
+                       { url => $input, reason => 'path_only' });
+    }
+
     my $result;
     # Launchpad URLs
     if ($uri->authority =~ /launchpad.net$/) {

template/en/default/global/user-error.html.tmpl

@@ -245,6 +245,8 @@
     <code>[% url FILTER html %]</code> is not a valid URL to [% terms.abug %].
     [% IF reason == 'http' %]
       URLs must start with "http" or "https".
+    [% ELSIF reason == 'path_only' %]
+      You must specify a full URL.
     [% ELSIF reason == 'show_bug' %]
       [%+ field_descs.see_also %] URLs should point to one of:
       <ul>