prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  $UID not spitting out UID
  **Describe the bug**
  A hacker found a way to get inside the cowrie box and executed "echo $UID". The reply that came back was empty, and the hacker disconnected. My normal box returned the UID.
  
  **To Reproduce**
  Steps to reproduce the behavior:
  1. Connect to linux machine
  2. Type in "Echo $UID" (response should be something like 1001 or 0)
  3. Connect to cowrie
  4. Type in "echo $UID"
  5. See nothing replied on screen.
  
  **Expected behavior**
  When someone uses the variable $UID, get the variable from the honeyfs/etc/passwd file or return 0.
  
  **Server (please complete the following information):**
   - OS: Linux nanopineo2 5.8.6-sunxi64 #20.08.2 SMP Fri Sep 4 08:52:31 CEST 2020 aarch64 GNU/Linux
   - Python: Python 3.7.3
  
  **Additional context**
  My hackers seem to get smarter each day...
  
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `src/cowrie/shell/session.py`
  Content:
  ```
  1 # Copyright (c) 2009-2014 Upi Tamminen <desaster@gmail.com>
  2 # See the COPYRIGHT file for more information
  3 
  4 from __future__ import absolute_import, division
  5 
  6 from twisted.conch.interfaces import ISession
  7 from twisted.conch.ssh import session
  8 from twisted.python import log
  9 
  10 from zope.interface import implementer
  11 
  12 from cowrie.insults import insults
  13 from cowrie.shell import protocol
  14 
  15 
  16 @implementer(ISession)
  17 class SSHSessionForCowrieUser(object):
  18 
  19     def __init__(self, avatar, reactor=None):
  20         """
  21         Construct an C{SSHSessionForCowrieUser}.
  22 
  23         @param avatar: The L{CowrieUser} for whom this is an SSH session.
  24         @param reactor: An L{IReactorProcess} used to handle shell and exec
  25             requests. Uses the default reactor if None.
  26         """
  27         self.protocol = None
  28         self.avatar = avatar
  29         self.server = avatar.server
  30         self.uid = avatar.uid
  31         self.gid = avatar.gid
  32         self.username = avatar.username
  33         self.environ = {
  34             'LOGNAME': self.username,
  35             'SHELL': '/bin/bash',
  36             'USER': self.username,
  37             'HOME': self.avatar.home,
  38             'TMOUT': '1800',
  39             'UID': self.uid}
  40         if self.uid == 0:
  41             self.environ['PATH'] = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'
  42         else:
  43             self.environ['PATH'] = '/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games'
  44 
  45         self.server.initFileSystem()
  46 
  47         if self.avatar.temporary:
  48             self.server.fs.mkdir(self.avatar.home, self.uid, self.gid, 4096, 755)
  49 
  50     def openShell(self, processprotocol):
  51         self.protocol = insults.LoggingServerProtocol(
  52             protocol.HoneyPotInteractiveProtocol, self)
  53         self.protocol.makeConnection(processprotocol)
  54         processprotocol.makeConnection(session.wrapProtocol(self.protocol))
  55 
  56     def getPty(self, terminal, windowSize, attrs):
  57         self.environ['TERM'] = terminal.decode("utf-8")
  58         log.msg(
  59             eventid='cowrie.client.size',
  60             width=windowSize[1],
  61             height=windowSize[0],
  62             format='Terminal Size: %(width)s %(height)s'
  63         )
  64         self.windowSize = windowSize
  65         return None
  66 
  67     def execCommand(self, processprotocol, cmd):
  68         self.protocol = insults.LoggingServerProtocol(
  69             protocol.HoneyPotExecProtocol, self, cmd)
  70         self.protocol.makeConnection(processprotocol)
  71         processprotocol.makeConnection(session.wrapProtocol(self.protocol))
  72 
  73     def closed(self):
  74         """
  75         this is reliably called on both logout and disconnect
  76         we notify the protocol here we lost the connection
  77         """
  78         if self.protocol:
  79             self.protocol.connectionLost("disconnected")
  80             self.protocol = None
  81 
  82     def eofReceived(self):
  83         if self.protocol:
  84             self.protocol.eofReceived()
  85 
  86     def windowChanged(self, windowSize):
  87         self.windowSize = windowSize
  88
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/src/cowrie/shell/session.py b/src/cowrie/shell/session.py
  --- a/src/cowrie/shell/session.py
  +++ b/src/cowrie/shell/session.py
  @@ -36,7 +36,7 @@
               'USER': self.username,
               'HOME': self.avatar.home,
               'TMOUT': '1800',
  -            'UID': self.uid}
  +            'UID': str(self.uid)}
           if self.uid == 0:
               self.environ['PATH'] = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'
           else:
  
verification_info: {"golden_diff": "diff --git a/src/cowrie/shell/session.py b/src/cowrie/shell/session.py\n--- a/src/cowrie/shell/session.py\n+++ b/src/cowrie/shell/session.py\n@@ -36,7 +36,7 @@\n             'USER': self.username,\n             'HOME': self.avatar.home,\n             'TMOUT': '1800',\n-            'UID': self.uid}\n+            'UID': str(self.uid)}\n         if self.uid == 0:\n             self.environ['PATH'] = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'\n         else:\n", "issue": "$UID not spitting out UID\n**Describe the bug**\r\nA hacker found a way to get inside the cowrie box and executed \"echo $UID\". The reply that came back was empty, and the hacker disconnected. My normal box returned the UID.\r\n\r\n**To Reproduce**\r\nSteps to reproduce the behavior:\r\n1. Connect to linux machine\r\n2. Type in \"Echo $UID\" (response should be something like 1001 or 0)\r\n3. Connect to cowrie\r\n4. Type in \"echo $UID\"\r\n5. See nothing replied on screen.\r\n\r\n**Expected behavior**\r\nWhen someone uses the variable $UID, get the variable from the honeyfs/etc/passwd file or return 0.\r\n\r\n**Server (please complete the following information):**\r\n - OS: Linux nanopineo2 5.8.6-sunxi64 #20.08.2 SMP Fri Sep 4 08:52:31 CEST 2020 aarch64 GNU/Linux\r\n - Python: Python 3.7.3\r\n\r\n**Additional context**\r\nMy hackers seem to get smarter each day...\r\n\n", "before_files": [{"content": "# Copyright (c) 2009-2014 Upi Tamminen <desaster@gmail.com>\n# See the COPYRIGHT file for more information\n\nfrom __future__ import absolute_import, division\n\nfrom twisted.conch.interfaces import ISession\nfrom twisted.conch.ssh import session\nfrom twisted.python import log\n\nfrom zope.interface import implementer\n\nfrom cowrie.insults import insults\nfrom cowrie.shell import protocol\n\n\n@implementer(ISession)\nclass SSHSessionForCowrieUser(object):\n\n    def __init__(self, avatar, reactor=None):\n        \"\"\"\n        Construct an C{SSHSessionForCowrieUser}.\n\n        @param avatar: The L{CowrieUser} for whom this is an SSH session.\n        @param reactor: An L{IReactorProcess} used to handle shell and exec\n            requests. Uses the default reactor if None.\n        \"\"\"\n        self.protocol = None\n        self.avatar = avatar\n        self.server = avatar.server\n        self.uid = avatar.uid\n        self.gid = avatar.gid\n        self.username = avatar.username\n        self.environ = {\n            'LOGNAME': self.username,\n            'SHELL': '/bin/bash',\n            'USER': self.username,\n            'HOME': self.avatar.home,\n            'TMOUT': '1800',\n            'UID': self.uid}\n        if self.uid == 0:\n            self.environ['PATH'] = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'\n        else:\n            self.environ['PATH'] = '/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games'\n\n        self.server.initFileSystem()\n\n        if self.avatar.temporary:\n            self.server.fs.mkdir(self.avatar.home, self.uid, self.gid, 4096, 755)\n\n    def openShell(self, processprotocol):\n        self.protocol = insults.LoggingServerProtocol(\n            protocol.HoneyPotInteractiveProtocol, self)\n        self.protocol.makeConnection(processprotocol)\n        processprotocol.makeConnection(session.wrapProtocol(self.protocol))\n\n    def getPty(self, terminal, windowSize, attrs):\n        self.environ['TERM'] = terminal.decode(\"utf-8\")\n        log.msg(\n            eventid='cowrie.client.size',\n            width=windowSize[1],\n            height=windowSize[0],\n            format='Terminal Size: %(width)s %(height)s'\n        )\n        self.windowSize = windowSize\n        return None\n\n    def execCommand(self, processprotocol, cmd):\n        self.protocol = insults.LoggingServerProtocol(\n            protocol.HoneyPotExecProtocol, self, cmd)\n        self.protocol.makeConnection(processprotocol)\n        processprotocol.makeConnection(session.wrapProtocol(self.protocol))\n\n    def closed(self):\n        \"\"\"\n        this is reliably called on both logout and disconnect\n        we notify the protocol here we lost the connection\n        \"\"\"\n        if self.protocol:\n            self.protocol.connectionLost(\"disconnected\")\n            self.protocol = None\n\n    def eofReceived(self):\n        if self.protocol:\n            self.protocol.eofReceived()\n\n    def windowChanged(self, windowSize):\n        self.windowSize = windowSize\n", "path": "src/cowrie/shell/session.py"}], "after_files": [{"content": "# Copyright (c) 2009-2014 Upi Tamminen <desaster@gmail.com>\n# See the COPYRIGHT file for more information\n\nfrom __future__ import absolute_import, division\n\nfrom twisted.conch.interfaces import ISession\nfrom twisted.conch.ssh import session\nfrom twisted.python import log\n\nfrom zope.interface import implementer\n\nfrom cowrie.insults import insults\nfrom cowrie.shell import protocol\n\n\n@implementer(ISession)\nclass SSHSessionForCowrieUser(object):\n\n    def __init__(self, avatar, reactor=None):\n        \"\"\"\n        Construct an C{SSHSessionForCowrieUser}.\n\n        @param avatar: The L{CowrieUser} for whom this is an SSH session.\n        @param reactor: An L{IReactorProcess} used to handle shell and exec\n            requests. Uses the default reactor if None.\n        \"\"\"\n        self.protocol = None\n        self.avatar = avatar\n        self.server = avatar.server\n        self.uid = avatar.uid\n        self.gid = avatar.gid\n        self.username = avatar.username\n        self.environ = {\n            'LOGNAME': self.username,\n            'SHELL': '/bin/bash',\n            'USER': self.username,\n            'HOME': self.avatar.home,\n            'TMOUT': '1800',\n            'UID': str(self.uid)}\n        if self.uid == 0:\n            self.environ['PATH'] = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'\n        else:\n            self.environ['PATH'] = '/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games'\n\n        self.server.initFileSystem()\n\n        if self.avatar.temporary:\n            self.server.fs.mkdir(self.avatar.home, self.uid, self.gid, 4096, 755)\n\n    def openShell(self, processprotocol):\n        self.protocol = insults.LoggingServerProtocol(\n            protocol.HoneyPotInteractiveProtocol, self)\n        self.protocol.makeConnection(processprotocol)\n        processprotocol.makeConnection(session.wrapProtocol(self.protocol))\n\n    def getPty(self, terminal, windowSize, attrs):\n        self.environ['TERM'] = terminal.decode(\"utf-8\")\n        log.msg(\n            eventid='cowrie.client.size',\n            width=windowSize[1],\n            height=windowSize[0],\n            format='Terminal Size: %(width)s %(height)s'\n        )\n        self.windowSize = windowSize\n        return None\n\n    def execCommand(self, processprotocol, cmd):\n        self.protocol = insults.LoggingServerProtocol(\n            protocol.HoneyPotExecProtocol, self, cmd)\n        self.protocol.makeConnection(processprotocol)\n        processprotocol.makeConnection(session.wrapProtocol(self.protocol))\n\n    def closed(self):\n        \"\"\"\n        this is reliably called on both logout and disconnect\n        we notify the protocol here we lost the connection\n        \"\"\"\n        if self.protocol:\n            self.protocol.connectionLost(\"disconnected\")\n            self.protocol = None\n\n    def eofReceived(self):\n        if self.protocol:\n            self.protocol.eofReceived()\n\n    def windowChanged(self, windowSize):\n        self.windowSize = windowSize\n", "path": "src/cowrie/shell/session.py"}]}