Merge pull request rapid7#21073 from Hemang360/fix-duplicate-job

Fix duplicate handler jobs caused by stop_handler on repeated run

Author: adfoster-r7

lib/msf/core/handler/reverse_http.rb

@@ -239,11 +239,13 @@ def setup_handler
     self.service.server_name = datastore['HttpServerName']
 
     # Add the new resource
-    service.add_resource((luri + "/").gsub("//", "/"),
+    resource_path = (luri + "/").gsub("//", "/")
+    service.add_resource(resource_path,
       'Proc' => Proc.new { |cli, req|
         on_request(cli, req)
       },
       'VirtualDirectory' => true)
+    self.resource_added = true
 
     print_status("Started #{scheme.upcase} reverse handler on #{listener_uri(local_addr)}")
     lookup_proxy_settings
@@ -259,13 +261,17 @@ def setup_handler
   #
   def stop_handler
     if self.service
-      self.service.remove_resource((luri + "/").gsub("//", "/"))
+      if self.resource_added
+        self.service.remove_resource((luri + "/").gsub("//", "/"))
+        self.resource_added = false
+      end
       self.service.deref
       self.service = nil
     end
   end
 
   attr_accessor :service # :nodoc:
+  attr_accessor :resource_added # :nodoc:
 
 protected
 

spec/lib/msf/core/handler/reverse_http_spec.rb

@@ -32,6 +32,40 @@ def ssl?
 
   end
 
+  describe '#stop_handler' do
+    let(:mock_service) { double('service') }
+    let(:payload) { create_payload }
+
+    context 'when add_resource raised and resource was not added' do
+      before do
+        payload.service = mock_service
+        payload.resource_added = false
+      end
+
+      it 'does not remove the resource but still derefs the service' do
+        expect(mock_service).not_to receive(:remove_resource)
+        expect(mock_service).to receive(:deref)
+        payload.stop_handler
+        expect(payload.service).to be_nil
+      end
+    end
+
+    context 'when the resource was successfully added' do
+      before do
+        payload.service = mock_service
+        payload.resource_added = true
+      end
+
+      it 'removes the resource and derefs the service' do
+        expect(mock_service).to receive(:remove_resource).with('/')
+        expect(mock_service).to receive(:deref)
+        payload.stop_handler
+        expect(payload.service).to be_nil
+        expect(payload.resource_added).to eq(false)
+      end
+    end
+  end
+
   describe '#luri' do
     subject(:luri) do
       create_payload.luri