Bug 106664

I can't reproduce with httpd-2.0.47-8, can you update to that and try again?

Hmm, still present:

[...]
root@wombat:~> rpm -q glibc httpd; uname -r
glibc-2.3.2-98
httpd-2.0.47-8
2.4.22-1.2087.nptl
root@wombat:~> sysctl -w kernel.exec-shield=0
kernel.exec-shield = 0
root@wombat:~> service httpd restart
Stopping httpd:                                            [  OK  ]
Starting httpd:                                            [FAILED]
root@wombat:~> httpd
Segmentation fault
root@wombat:~> sysctl -w kernel.exec-shield=1
kernel.exec-shield = 1
root@wombat:~> service httpd restart
Stopping httpd:                                            [FAILED]
Starting httpd:                                            [  OK  ]
root@wombat:~>
[...]

Any additional info you might need? FYI, the machine should have virtually all
packages installed.

Can you:

strace httpd
rpm -qf /etc/httpd/conf.d/*.conf

I'd ask for a backtrace but gdb doesn't support PIE yet :(

Here you are:

[...]
root@wombat:~> sysctl -w kernel.exec-shield=0
kernel.exec-shield = 0
root@wombat:~> service httpd stop
Stopping httpd:                                            [  OK  ]
root@wombat:~> strace httpd
execve("/usr/sbin/httpd", ["httpd"], [/* 28 vars */]) = 0
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
+++ killed by SIGSEGV +++
root@wombat:~> rpm -qf /etc/httpd/conf.d/*.conf
file /etc/httpd/conf.d/chorios.conf is not owned by any package
file /etc/httpd/conf.d/homedir.conf is not owned by any package
mod_perl-1.99_09-10
php-4.3.3-2
mod_python-3.0.3-3
squirrelmail-1.4.0-1
mod_ssl-2.0.47-8
mod_dav_svn-0.31.0-1
root@wombat:~>
[...]

It is very suspicious to me that it segfaults immediately before even trying to
load libraries etc. Correction to my previous post: prelink is _not_ installed
(I guessed that wrong prelinkage could be the culprit) -- shall I leave it like
that or install it?

You could try something like

LD_DEBUG=all LD_DEBUG_OUTPUT=/tmp/httpd /usr/sbin/httpd

Jakub, any ideas about this?

Created attachment 95101 [details]
LD_DEBUG output of httpd run with exec-shield off

That was the file from strace, can you attach the one from httpd too?

No, because running it on httpd alone doesn't produce a file.

ld.so problem? toolchain problem? kernel problem?

Calling QA people - can anyone reproduce these problems on Fedora Test 3? I
still can't.  If there is some problem with PIE then we need to get it fixed ASAP.

[root@pepsi root]# rpm -q httpd
httpd-2.0.47-8
[root@pepsi root]# uname -r
2.4.22-1.2088.nptl

Ah ha.  I *can* reproduce this on Test 3 if I "prelink -u /usr/sbin/httpd".

execve("/usr/sbin/httpd", ["/usr/sbin/httpd"], [/* 31 vars */]) = 0
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
+++ killed by SIGSEGV +++

Interestingly (or maybe it isn't), I *can* start up httpd OK using:

# /lib/ld-linux.so.2 /usr/sbin/httpd

Jakub are you looking into this?

Ingo tracked this down to a kernel problem.

Reproduction case was having:

/lib/ld-linux.so.2 not prelinked
exec-shield off
executable with a large bss

e.g. int foo[30000]; int main() {return 0;}

*** Bug 105772 has been marked as a duplicate of this bug. ***

Fix will be in tomorrows rawhide push.

Fixed.