Bug 231908 - Double free or corruption detected by glibc when using mem_cache_module and mod_python
Summary: Double free or corruption detected by glibc when using mem_cache_module and m...
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Fedora
Classification: Fedora
Component: httpd
Version: 5
Hardware: x86_64
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Joe Orton
QA Contact:
URL:
Whiteboard: bzcl34nup
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2007-03-12 22:10 UTC by Andy Price
Modified: 2008-05-06 19:20 UTC (History)
1 user (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2008-05-06 19:20:46 UTC
Type: ---
Embargoed:


Attachments (Terms of Use)
The vhost file that triggers the bug (789 bytes, text/plain)
2007-03-12 22:10 UTC, Andy Price
no flags Details
Output of running symclash.py (2.08 KB, text/plain)
2007-03-12 22:47 UTC, Andy Price
no flags Details

Description Andy Price 2007-03-12 22:10:51 UTC
Description of problem:

Since this morning browsing to a vhost using mod_python with mem_cache_module
loaded in httpd.conf gives glibc "double free or corruption" errors in
/var/log/httpd/error_log and makes httpd processes stick around.

Version-Release number of selected component (if applicable):

httpd-2.2.2-1.2
mod_python-3.2.8-3

How reproducible:

Happens every time I uncomment the following line in httpd.conf:
#LoadModule mem_cache_module modules/mod_mem_cache.so

Steps to Reproduce:
1. Set up a vhost as shown in the attached vhost file
2. Make sure the following line is in your httpd.conf:
LoadModule mem_cache_module modules/mod_mem_cache.so
3. Reload httpd
4. tail -f /var/log/httpd/error_log
5. Open a web browser and browse to the vhost
  
Actual results:
1. No response received by the browser
2. In /var/log/httpd/error_log:
*** glibc detected *** /usr/sbin/httpd: double free or corruption (fasttop):
0x000055555623b700 ***

3. Each time I reload the browser, a new httpd process starts and a new "double
free or corruption" line is added to the error_log. The processes persist until
killed.

Expected results:
1. The vhost's web page to load nicely in the browser
2. No errors in error_log
3. httpd processes only stick around until the end of the session

Additional info:
1. Commenting out the LoadModule line mentioned above in httpd.conf fixes it.
2. Bug #205018 seems like it could be related (it's where I found the fix) but
it's closed.
3. Bug #230127 might possibly also be related
4. Packages upgraded this morning:

Installed: python-sqlite2.x86_64 1:2.3.2-2.fc5
Updated: mod_suphp.x86_64 0.6.2-1.fc5
Updated: trac.noarch 0.10.3.1-1.fc5

Comment 1 Andy Price 2007-03-12 22:10:55 UTC
Created attachment 149875 [details]
The vhost file that triggers the bug

Comment 2 Joe Orton 2007-03-12 22:20:57 UTC
This is undoubtedly a global symbol collision.  It should be fixed in
mod_mem_cache, no doubt; it would be useful to know exactly what the problem is:
can you download http://people.redhat.com/jorton/symclash/symclash.py

and run as follows:

# ./symclash.py /usr/lib64/httpd/modules/mod_mem_cache.so \
    /usr/lib64/python2.4/{*/*.so,*/*/*.so,*/*/*/*.so}

and attach the output to this bug report.

Comment 3 Andy Price 2007-03-12 22:47:16 UTC
Created attachment 149878 [details]
Output of running symclash.py

As requested

Comment 4 Joe Orton 2007-03-12 22:57:33 UTC
Great, thanks.  The collision is:

Clashes for /usr/lib64/python2.4/site-packages/pysqlite2/_sqlite.so:
  with /usr/lib64/python2.4/site-packages/_sqlite.so => init_sqlite
  with /usr/lib64/httpd/modules/mod_mem_cache.so => cache_init


Comment 5 Joe Orton 2007-05-25 13:12:09 UTC
The fix for this needs to go upstream first, but is well understood.  (the
symbol collision has been fixed in python-sqlite2 also, for the record)

Comment 6 Bug Zapper 2008-04-04 06:30:58 UTC
Fedora apologizes that these issues have not been resolved yet. We're
sorry it's taken so long for your bug to be properly triaged and acted
on. We appreciate the time you took to report this issue and want to
make sure no important bugs slip through the cracks.

If you're currently running a version of Fedora Core between 1 and 6,
please note that Fedora no longer maintains these releases. We strongly
encourage you to upgrade to a current Fedora release. In order to
refocus our efforts as a project we are flagging all of the open bugs
for releases which are no longer maintained and closing them.
http://fedoraproject.org/wiki/LifeCycle/EOL

If this bug is still open against Fedora Core 1 through 6, thirty days
from now, it will be closed 'WONTFIX'. If you can reporduce this bug in
the latest Fedora version, please change to the respective version. If
you are unable to do this, please add a comment to this bug requesting
the change.

Thanks for your help, and we apologize again that we haven't handled
these issues to this point.

The process we are following is outlined here:
http://fedoraproject.org/wiki/BugZappers/F9CleanUp

We will be following the process here:
http://fedoraproject.org/wiki/BugZappers/HouseKeeping to ensure this
doesn't happen again.

And if you'd like to join the bug triage team to help make things
better, check out http://fedoraproject.org/wiki/BugZappers

Comment 7 Bug Zapper 2008-05-06 19:20:44 UTC
This bug is open for a Fedora version that is no longer maintained and
will not be fixed by Fedora. Therefore we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen thus bug against that version.

Thank you for reporting this bug and we are sorry it could not be fixed.


Note You need to log in before you can comment on or make changes to this bug.