Ubuntu
python2.6 package

Python Segfault on os.exec

Bug #418848 reported by Pehr Söderman on 2009-08-25

This bug affects 2 people

Affects		Status	Importance	Assigned to	Milestone
	Python	Invalid	Undecided	Unassigned
	python2.6 (Ubuntu)	Fix Released	Low	Unassigned

Bug Description

Binary package hint: python

Ubuntu Karmic, latest python from aptitude (2.6.2-0ubuntu1).

Using the exec command causes segfaults in python. For example:

Python 2.6.2+ (release26-maint, Jul 24 2009, 16:16:12)
[GCC 4.4.1] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.execlp('true')
Segmentation fault
~>

Expected behavior (from another Linux system):
Python 2.6 (r26:66714, Feb 3 2009, 20:49:49)
[GCC 4.3.2 [gcc-4_3-branch revision 141291]] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.execlp('true')
~>

This has been confirmed on 3 different computers running karmic.

Related branches

lp:debian/python2.6

Revision history for this message

Pehr Söderman (pehrs) wrote on 2009-08-25:

Simple pyton script to reproduce the bug Edit (32 bytes, text/x-python)

Revision history for this message

Josh Kupershmidt (schmiddy) wrote on 2009-08-26:

I don't have a Karmic install handy to check the OP's reported behavior, but I can confirm that I *don't* get a segfault in Jaunty:

$ python
Python 2.6.2 (release26-maint, Apr 19 2009, 01:56:41)
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.execlp('true')
$

Revision history for this message

Marcin Wider (mwider) wrote on 2009-11-16:

I can reproduce this SegFault with Python 2.6.4 (r264:75706, Nov 2 2009, 14:38:03) - Karmic

Changed in python-defaults (Ubuntu):
status:	New → Confirmed

Revision history for this message

Matthias Klose (doko) wrote on 2009-11-16:

this is wrong code (although python shouldn't crash). execlp requires at least two arguments.

Changed in python-defaults (Ubuntu):
importance:	Undecided → Low
status:	Confirmed → Triaged

Revision history for this message

Matthias Klose (doko) wrote on 2010-03-16:

fixed in python3

Bug Watch Updater (bug-watch-updater) on 2010-03-16

Changed in python:
status:	Unknown → New

Matthias Klose (doko) on 2010-03-16

affects:	python-defaults (Ubuntu) → python2.6 (Ubuntu)
Changed in python2.6 (Ubuntu):
status:	Triaged → In Progress

Revision history for this message

Launchpad Janitor (janitor) wrote on 2010-03-20:

This bug was fixed in the package python2.6 - 2.6.5-1ubuntu1

---------------
python2.6 (2.6.5-1ubuntu1) lucid; urgency=low

* Merge with Debian (2.6.5-1).

python2.6 (2.6.5-1) unstable; urgency=low

  * Python 2.6.5 final release.
  * Fix issue #4961: Inconsistent/wrong result of askyesno function in
    tkMessageBox with Tcl8.5. LP: #462950.
  * Issue #8154, fix segfault with os.execlp('true'). LP: #418848.
  * Apply proposed patch for issue #8032, gdb7 hooks for debugging.

python2.6 (2.6.5~rc2-2) unstable; urgency=low

  * Add copyright notices for the readline and _ssl extensions.
    Closes: #573866.
  * Backport issue #8140: Extend compileall to compile single files.
    Add -i option.
  * Backport issue #6949, build _bsddb extension with db-4.8.x.

python2.6 (2.6.5~rc2-1) unstable; urgency=low

  * Python 2.6.5 release candidate 2.
    - Replace the Monty Python audio test file. Closes: #568674.
  * Fix build failure on sparc64. Closes: #570845.
-- Matthias Klose <email address hidden> Sat, 20 Mar 2010 03:57:17 +0100

Changed in python2.6 (Ubuntu):
status:	In Progress → Fix Released

Bug Watch Updater (bug-watch-updater) on 2010-03-20

Changed in python:
status:	New → Fix Released

Revision history for this message

R. David Murray (rdmurray) wrote on 2010-03-20:

This is not a bug in python. It is most likely a bug in /bin/true, crashing when called with argc set to 0. As noted in the upstream tracker, the fix applied to python is likely to break currently working python code.

Bug Watch Updater (bug-watch-updater) on 2010-03-21