https://bz.apache.org/bugzilla/show_bug.cgi?id=61558
Bug ID: 61558 Summary: Apache 2.4.27 crashes often when restarting the service. segfault in libdl-2.24.so or apache2 Product: Apache httpd-2 Version: 2.4.27 Hardware: All OS: Linux Status: NEW Severity: normal Priority: P2 Component: All Assignee: bugs@httpd.apache.org Reporter: pantal...@outlook.com Target Milestone: --- Created attachment 35362 --> https://bz.apache.org/bugzilla/attachment.cgi?id=35362&action=edit apache2ctl-t-V-M.txt Hi, I have been struggling for quite some time now on a dedicated dev server with Apache "sometimes" crashing when the Apache service is started for the first time after a server boot, or when the Apache service is restarted. It became claear after a while that it crashes at least once out of +- 25 times when I restart the Apache service (see below for the test script). Apache recovers from it somehow. I "think" that an MPM worker child process crashes, and that main Apache process then starts another one, which always starts correctly. Now is a good time to report it because I would like to upgrade some production servers from Ubuntu 14.04.5 LTS trusty to Ubuntu Artful V17.10 in a few months time. * Environment: - O.S.: Ubuntu 17.04 Zesty (Desktop edition) - Ubuntu Package: apache2-bin:amd64/zesty 2.4.27-5.1+ubuntu17.04.1+deb.sury.org+1 * Notes: - The Apache dbg packages have been installed. `apt --yes install apache2-dbg libapr1-dbg libaprutil1-dbg gdb` - This is a stable bare-metal server that is online 24x7 with no other problems. - I have removed the modules mod_security2 and mod_spamhaus, but it did not help. - No Apache sites are currently enabled, but it did not help. - I tried to reproduce it in a VM with a fresh install of Ubuntu Zesty and Apache 2.4.27 but then the crash never happens. * Reproducible test script #Bash #@doc The server will crash at least once every +-10 minutes when this script is running. while true do systemctl stop apache2; systemctl start apache2; journalctl --lines=50 --unit=apache2; sleep 10; done * The crash details in the syslog varies as follows: "error 4 in apache2" or "error 14 in libdl-2.24.so". Sep 22 11:44:04 s3black kernel: [36459.658587] apache2[12579]: segfault at 7f47d733a8c0 ip 0000559c2b73fdd4 sp 00007ffeaded5fd0 error 4 in apache2[559c2b703000+9e000] Sep 22 11:44:04 s3black systemd[1]: apache2.service: Main process exited, code=dumped, status=11/SEGV Sep 22 11:48:06 s3black kernel: [36701.689499] apache2[14568]: segfault at 7f06524308c0 ip 00005578dc332dd4 sp 00007ffdd48f9210 error 4 in apache2[5578dc2f6000+9e000] Sep 22 11:48:06 s3black systemd[1]: apache2.service: Main process exited, code=dumped, status=11/SEGV Sep 22 13:19:43 s3black kernel: [42198.677611] apache2[1417]: segfault at 7feb5dd26ad0 ip 00007feb5dd26ad0 sp 00007ffd97212488 error 14 in libdl-2.24.so[7feb607b0000+3000] Sep 22 13:19:43 s3black systemd[1]: apache2.service: Main process exited, code=dumped, status=11/SEGV Sep 22 13:41:57 s3black kernel: [43532.685282] apache2[12965]: segfault at 7f3079b9dad0 ip 00007f3079b9dad0 sp 00007ffe3b47be88 error 14 in libdl-2.24.so[7f307c627000+3000] Sep 22 13:49:28 s3black kernel: [43983.678591] apache2[16930]: segfault at 7f0f0387d8c0 ip 000056527483fdd4 sp 00007ffd4282ba10 error 4 in apache2[565274803000+9e000] * Crash report script: #Bash cd /var/crash/ apport-retrace --rebuild-package-info --sandbox=system _usr_sbin_apache2.0.crash rm --verbose -rf unpacked apport-unpack _usr_sbin_apache2.0.crash unpacked cd unpacked # gdb: get info about the backtrace echo "thread apply all bt full" | gdb /usr/sbin/apache2 CoreDump * The top of the thread stacktrace #0 0x00007feb5dd26ad0 in ?? () #1 0x00005596bd360e0e in ap_run_mpm_query (query_code=query_code@entry=2, result=result@entry=0x7ffd972124ec, _rv=_rv@entry=0x7ffd972124c4) at mpm_common.c:97 92: (apr_pool_t * pchild, server_rec * s), 93: (pchild, s), OK, DECLINED) 94: AP_IMPLEMENT_HOOK_RUN_FIRST(int, mpm, 95: (apr_pool_t *pconf, apr_pool_t *plog, server_rec *s), 96: (pconf, plog, s), DECLINED) 97: AP_IMPLEMENT_HOOK_RUN_FIRST(int, mpm_query, 98: (int query_code, int *result, apr_status_t *_rv), 99: (query_code, result, _rv), DECLINED) 100: AP_IMPLEMENT_HOOK_RUN_FIRST(apr_status_t, mpm_register_timed_callback, 101: (apr_time_t t, ap_mpm_callback_fn_t *cbfn, void *baton), 102: (t, cbfn, baton), APR_ENOTIMPL) #2 0x00005596bd361b9e in ap_mpm_query (query_code=query_code@entry=2, result=result@entry=0x7ffd972124ec) at mpm_common.c:419 414: 415: AP_DECLARE(apr_status_t) ap_mpm_query(int query_code, int *result) 416: { 417: apr_status_t rv; 418: 419: if (ap_run_mpm_query(query_code, result, &rv) == DECLINED) { 420: rv = APR_EGENERAL; 421: } 422: 423: return rv; 424: } * Attachments. I have collected as much info as possible. Thanks for your help to find the cause of this crash. If you need more information then do not hesitate to ask. -- Rolf. -- You are receiving this mail because: You are the assignee for the bug. --------------------------------------------------------------------- To unsubscribe, e-mail: bugs-unsubscr...@httpd.apache.org For additional commands, e-mail: bugs-h...@httpd.apache.org