ab crashed with SIGSEGV in main()

[Sasha Levin]

Binary package hint: apache2-utils

I ran ab with a high number of connections (-n 1000000000) and got the error.

ProblemType: Crash
Architecture: amd64
Date: Tue Oct 13 18:30:18 2009
DistroRelease: Ubuntu 9.10
ExecutablePath: /usr/sbin/ab
NonfreeKernelModules: fglrx
Package: apache2-utils 2.2.12-1ubuntu2
ProcCmdline: ab -c 1000 -n 1000000000 -r 192.168.0.127/
ProcEnviron:
 SHELL=/bin/bash
 LANG=en_US.UTF-8
ProcVersionSignature: Ubuntu 2.6.31-13.45-generic
SegvAnalysis:
 Segfault happened at: 0x7f899657cf67: mov %rax,0x0(%rbp)
 PC (0x7f899657cf67) ok
 source "%rax" ok
 destination "0x0(%rbp)" (0x00000000) not located in a known VMA region (needed writable region)!
SegvReason: writing NULL VMA
Signal: 11
SourcePackage: apache2
StacktraceTop:
 ?? () from /usr/sbin/ab
 ?? () from /usr/sbin/ab
 main () from /usr/sbin/ab
Title: ab crashed with SIGSEGV in main()
Uname: Linux 2.6.31-13-generic x86_64
UserGroups:

[Chuck Short (zulcss)]

Can you give the exact command you used to get this crash dump?

Thanks
chuck

[Sasha Levin (sasha-comsleep)]

The exact command was in the original report.

"ab -c 1000 -n 1000000000 -r 192.168.0.127/"

Sasha.

[Apport retracing service (apport)]

StacktraceTop:close_connection (c=0x7f8994280560)
test ()
main (argc=7, argv=0x7fff77762d78)

[Chuck Short (zulcss)]

I was able to reproduce this on karmic.

Thanks
chuck

[Chuck Short (zulcss)]

This is the patch that fixes it:

http://svn.apache.org/viewvc?view=revision&revision=826497

chuck@kenny:~/work/server/bugs/karmic/apache/build$ ab -c 1000 -n 1000000000 -r 127.0.0.1/
This is ApacheBench, Version 2.3 <$Revision: 655654 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/

Benchmarking 127.0.0.1 (be patient)
Cannot allocate memory for result statistics
chuck@kenny:~/work/server/bugs/karmic/apache/build$

Will fix it for lucid and do an SRU.

Thanks for the bug report.

Regards
chuck

[Launchpad Janitor (janitor)]

This bug was fixed in the package apache2 - 2.2.14-5ubuntu2

---------------
apache2 (2.2.14-5ubuntu2) lucid; urgency=low

  * debian/patches/203_fix-ab-segfault.dpatch: Fix segfaulting ab when using really
    wacky options. (LP: #450501)
 -- Chuck Short <email address hidden> Mon, 08 Mar 2010 14:53:17 -0500