Prevent file descriptor leaks in user input handling

lib/msf/base/sessions/hwbridge.rb

@@ -102,18 +102,18 @@ def info
   # Initializes the console's I/O handles.
   #
   def init_ui(input, output)
-    self.user_input = input
-    self.user_output = output
+    super
+
     console.init_ui(input, output)
     console.set_log_source(log_source)
-
-    super
   end
 
   ##
   # :category: Msf::Session::Interactive implementors
   #
   # Resets the console's I/O handles.
+  # Does not call super - the session preserves its own user_input/user_output
+  # while only resetting the console's I/O.
   #
   def reset_ui
     console.unset_log_source

lib/msf/base/sessions/ldap.rb

@@ -108,18 +108,18 @@ def port
   # Initializes the console's I/O handles.
   #
   def init_ui(input, output)
-    self.user_input = input
-    self.user_output = output
+    super
+
     console.init_ui(input, output)
     console.set_log_source(log_source)
-
-    super
   end
 
   ##
   # :category: Msf::Session::Interactive implementors
   #
   # Resets the console's I/O handles.
+  # Does not call super - the session preserves its own user_input/user_output
+  # while only resetting the console's I/O.
   #
   def reset_ui
     console.unset_log_source

lib/msf/base/sessions/meterpreter.rb

@@ -370,18 +370,18 @@ def execute_file(full_path, args)
   # Initializes the console's I/O handles.
   #
   def init_ui(input, output)
-    self.user_input = input
-    self.user_output = output
+    super
+
     console.init_ui(input, output)
     console.set_log_source(log_source)
-
-    super
   end
 
   ##
   # :category: Msf::Session::Interactive implementors
   #
   # Resets the console's I/O handles.
+  # Does not call super - the session preserves its own user_input/user_output
+  # while only resetting the console's I/O.
   #
   def reset_ui
     console.unset_log_source

lib/msf/base/sessions/smb.rb

@@ -95,18 +95,18 @@ def port
   # Initializes the console's I/O handles.
   #
   def init_ui(input, output)
-    self.user_input = input
-    self.user_output = output
+    super
+
     console.init_ui(input, output)
     console.set_log_source(log_source)
-
-    super
   end
 
   ##
   # :category: Msf::Session::Interactive implementors
   #
   # Resets the console's I/O handles.
+  # Does not call super - the session preserves its own user_input/user_output
+  # while only resetting the console's I/O.
   #
   def reset_ui
     console.unset_log_source

lib/msf/base/sessions/sql.rb

@@ -96,6 +96,8 @@ def init_ui(input, output)
   end
 
   # Resets the console's I/O handles.
+  # Does not call super - the session preserves its own user_input/user_output
+  # while only resetting the console's I/O.
   #
   # @return [Object]
   def reset_ui

lib/rex/ui/subscriber.rb

@@ -127,6 +127,15 @@ def gets
   # Sets the input and output handles.
   #
   def init_ui(input = nil, output = nil)
+    # Release FDs held by Input::Buffer socket pairs
+    if user_input && user_input != input && user_input.respond_to?(:close)
+      begin
+        user_input.close
+      rescue IOError, Errno::EBADF => e
+        elog("init_ui: failed to close old user_input: #{e}") if defined?(elog)
+      end
+    end
+
     self.user_input  = input
     self.user_output = output
   end
@@ -135,6 +144,15 @@ def init_ui(input = nil, output = nil)
   # Disables input/output
   #
   def reset_ui
+    # Release FDs held by Input::Buffer socket pairs
+    if user_input.respond_to?(:close)
+      begin
+        user_input.close
+      rescue IOError, Errno::EBADF => e
+        elog("reset_ui: failed to close user_input: #{e}") if defined?(elog)
+      end
+    end
+
     self.user_input  = nil
     self.user_output = nil
   end