Recent changes to bugs

File Descriptor Leak on /dev/pmtx

2007-08-02T15:30:01Z

For each SSH session one file descriptor is leaked:

# python
Python 2.2.3 (#1, Jun 12 2003, 09:31:58)
[GCC 3.2.2 20030222 (Red Hat Linux 3.2.2-5)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import pyssh
>>> s=pyssh.Ssh()

--- switching to terminal 2

# ps -ef | grep python
root 12737 12730 0 10:59 pts/2 00:00:08 python /usr/lib/python2.2/site-packages/mpcsim/main.py
root 13592 13078 0 17:21 pts/6 00:00:00 python
root 13595 13137 0 17:21 pts/7 00:00:00 grep python
# lsof -p 13592 | grep ptmx | wc -l
0

--- switching back to terminal 1

>>> for i in range(10):
... s.login()
... s.logout()
...
User input required for ssh connection.
(login/logout spam)
>>>

--- switching back to terminal 2

# lsof -p 13592 | grep ptmx | wc -l
10

Following patch fixes this:

--- ptyext.orig.py 2007-08-02 17:27:13.000000000 +0200
+++ ptyext.py 2007-08-02 17:27:53.000000000 +0200
@@ -161,6 +161,8 @@
os.close(stdin_fd)
if stdout_fd > STDERR_FILENO:
os.close(stdout_fd)
+ if master_fd > STDERR_FILENO:
+ os.close(master_fd)

def spawn(argv, master_read=_read, stdin_read=_read, stdin_fd=STDIN_FILENO,
stdout_fd=STDOUT_FILENO):

blocks forever in Ssh.close() if two or more instances used

2007-01-24T16:18:11Z

If you create more than one instances of pyssh,Ssh in the same process, then the process hangs when you close() any of them.

The problem is that each instance registers a signal handler to handle SIGCHLD, so each of them sees the signal, and each of them calls a blocking os.waitpid() on the pid its own SSH process. When the first SIGCHLD arrives, all the instances call a blocking os.waitpid(), even those which do not expect their SSH subprocess to exit.

The solution is to use a nonblocking os.waitpid() call.

fssa.py tries to stat everything in /tmp

2006-09-22T16:52:14Z

Basically, fssa.py fails occassionaly when it tries to
stat things that it shouldn't. The following patch is a
fix.

13a14,15
> import glob
>
31,36c35,39
< for filename in os.listdir('/tmp'):
< file_stat = os.stat("/tmp/%s" % (filename))
< if file_stat[stat.ST_UID] == os.getuid() \ < and stat.S_ISDIR(file_stat[stat.ST_MODE]) \ < and filename.find('ssh-') == 0:
< candidate_dirs.append("/tmp/%s" %
filename)
---
> for filename in glob.glob('/tmp/ssh-*'):
> file_stat = os.stat(filename)
> if (file_stat[stat.ST_UID] == os.getuid() and
> stat.S_ISDIR(file_stat[stat.ST_MODE])):
> candidate_dirs.append(filename)