Bug#803043: mod_perl2 / Apache segfaults after upgrading from Wheezy to Jessie

[Patrick Matthäi]

Hi again,

this happened while I checked out a svn repository:

root at git:/tmp/apache# gdb /usr/sbin/apache2 -c core
GNU gdb (Debian 7.7.1+dfsg-5) 7.7.1
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Reading symbols from /usr/sbin/apache2...Reading symbols from 
/usr/lib/debug//usr/sbin/apache2...done.
done.

warning: core file may not match specified executable file.
[New LWP 8295]
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[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `/usr/sbin/apache2 -k start'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007f5918853add in read () at ../sysdeps/unix/syscall-template.S:81
81      ../sysdeps/unix/syscall-template.S: Datei oder Verzeichnis nicht 
gefunden.
(gdb) bt
#0  0x00007f5918853add in read () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f59193b59c7 in read (__nbytes=1, __buf=0x7fffad821e83, 
__fd=<optimized out>) at /usr/include/x86_64-linux-gnu/bits/unistd.h:44
#2  ap_mpm_podx_check (pod=<optimized out>) at mpm_unix.c:535
#3  0x00007f5911a7fb34 in child_main (child_num_arg=0) at worker.c:1341
#4  0x00007f5911a826c5 in make_child (s=0x7f59195afde0, slot=0) at 
worker.c:1427
#5  0x00007f5911a82745 in startup_children (number_to_start=2) at 
worker.c:1452
#6  0x00007f5911a8325e in worker_run (_pconf=0x7f59195d7028, 
plog=0x7f59195ab028, s=0x7f59195afde0) at worker.c:1811
#7  0x00007f591938ee7e in ap_run_mpm (pconf=0x7f59195d7028, 
plog=0x7f59195ab028, s=0x7f59195afde0) at mpm_common.c:94
#8  0x00007f59193883c3 in main (argc=3, argv=0x7fffad8222a8) at main.c:777
(gdb) bt full
#0  0x00007f5918853add in read () at ../sysdeps/unix/syscall-template.S:81
No locals.
#1  0x00007f59193b59c7 in read (__nbytes=1, __buf=0x7fffad821e83, 
__fd=<optimized out>) at /usr/include/x86_64-linux-gnu/bits/unistd.h:44
No locals.
#2  ap_mpm_podx_check (pod=<optimized out>) at mpm_unix.c:535
         c = 25 '\031'
         fd = 5
         rc = <optimized out>
#3  0x00007f5911a7fb34 in child_main (child_num_arg=0) at worker.c:1341
         threads = 0x7f591aa11910
         ts = 0x7f5919529110
         thread_attr = 0x7f5919529130
         start_thread_id = 0x7f5919529190
#4  0x00007f5911a826c5 in make_child (s=0x7f59195afde0, slot=0) at 
worker.c:1427
No locals.
#5  0x00007f5911a82745 in startup_children (number_to_start=2) at 
worker.c:1452
         i = 0
#6  0x00007f5911a8325e in worker_run (_pconf=0x7f59195d7028, 
plog=0x7f59195ab028, s=0x7f59195afde0) at worker.c:1811
         rv = -512
#7  0x00007f591938ee7e in ap_run_mpm (pconf=0x7f59195d7028, 
plog=0x7f59195ab028, s=0x7f59195afde0) at mpm_common.c:94
         pHook = <optimized out>
         n = 0
         rv = -1
#8  0x00007f59193883c3 in main (argc=3, argv=0x7fffad8222a8) at main.c:777
         c = 0 '\000'
         error = 0xfffffffffffffe00 <error: Cannot access memory at 
address 0xfffffffffffffe00>
         process = 0x7f59195e0118
         pconf = 0x7f59195d7028
         plog = 0x7f59195ab028
         ptemp = 0x7f59195ad028
         pcommands = 0x7f59195b5028
         opt = 0x7f59195b5118
         mod = 0x7f59195ec1c0 <ap_prelinked_modules+64>
         opt_arg = 0x7f59195e0028 "(@^\031Y\177"
         signal_server = 0xfffffffffffffe00
(gdb)

[Mon Oct 26 13:14:58.134998 2015] [core:notice] [pid 8291:tid 
140020654380928] AH00051: child pid 8295 exit signal Segmentation fault 
(11), possible coredump in /tmp/apache

And as I said it was enough here on this server to activate the perl 
module. Perl itself is not used.

-- 
/*
Mit freundlichem Gruß / With kind regards,
  Patrick Matthäi
  GNU/Linux Debian Developer

   Blog: http://www.linux-dev.org/
E-Mail: pmatthaei at debian.org
         patrick at linux-dev.org
*/