[tor-commits] [stem/master] Unexpected OSError from proc's connections() funciton

[atagar at torproject.org]

commit 3d4825791fd4258eecbc290842d031df8a75fefa
Author: Damian Johnson <atagar at torproject.org>
Date:   Tue Jan 19 09:43:48 2016 -0800

    Unexpected OSError from proc's connections() funciton
    
    We're documented as raising an IOError but our os.listdir() can potentially
    raise an exexpected OSError...
    
      Exception in thread Thread-5:
      Traceback (most recent call last):
        File "/usr/lib/python2.7/threading.py", line 810, in __bootstrap_inner
          self.run()
        File "/home/pi/nyx/nyx/util/tracker.py", line 382, in run
          is_successful = self._task(self._process_pid, self._process_name)
        File "/home/pi/nyx/nyx/util/tracker.py", line 503, in _task
          for conn in connection.get_connections(resolver, process_pid = process_pid, process_name = process_name):
        File "/usr/local/lib/python2.7/dist-packages/stem/util/connection.py", line 195, in get_connections
          return [Connection(*conn) for conn in stem.util.proc.connections(process_pid)]
        File "/usr/local/lib/python2.7/dist-packages/stem/util/proc.py", line 358, in connections
          for fd in os.listdir('/proc/%s/fd' % pid):
      OSError: [Errno 13] Permission denied: '/proc/32443/fd'
    
    Caught thanks to Derrick Oswald.
---
 stem/util/proc.py |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/stem/util/proc.py b/stem/util/proc.py
index 8093075..5d2219c 100644
--- a/stem/util/proc.py
+++ b/stem/util/proc.py
@@ -355,7 +355,12 @@ def connections(pid):
   start_time, parameter = time.time(), 'process connections'
   inodes = []
 
-  for fd in os.listdir('/proc/%s/fd' % pid):
+  try:
+    fd_contents = os.listdir('/proc/%s/fd' % pid)
+  except OSError as exc:
+    raise IOError('Unable to read our file descriptors: %s' % exc)
+
+  for fd in fd_contents:
     fd_path = '/proc/%s/fd/%s' % (pid, fd)
 
     try: