segfault in server/mpm/event/event.c:process_socket
We have seen consistent but infrequent segfaults of apache on a trusty production server with 2.4.7-1ubuntu4.13 (for more examples, see )
Oct 2 19:01:03 static kernel: [8029151.932468] apache2: segfault at 7fac797803a8 ip 00007fac90b345e0 sp 00007fac84ff8e20 error 6 in mod_mpm_
Taking the ip - base seems to put us at a consistent offset
(gdb) p/x 0x7fac90b345e0 - 0x7fac90b2e000
$1 = 0x65e0
$ addr2line -e ./mod_mpm_event.so 0x65e0
which is at the bottom of process_socket(), which looks like
1059 * Prevent this connection from writing to our connection state after it
1060 * is no longer associated with this thread. This would happen if the EOR
1061 * bucket is destroyed from the listener thread due to a connection abort
1062 * or timeout.
1064 c->sbh = NULL;
1064 seems at least plausible as a faulting location...
Some digging through httpd history reveals that this assignment was removed on the 2.4 branch with commit , which seems to be largely based on . Things have been shuffled around so much it's hard to tell exactly what might have avoided us going down this path. Even so I'm honestly not sure how to reproduce it -- on a fairly busy server it's seen at most a few times a day.