[Mod_nss-list] NSSSessionTickets causes some segfault in error log

[Rob Crittenden]

Oliver Graute wrote:
> Hello Rob,
> 
> here the Backtrace I got from gdb
> 
> gdb httpd
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> Reading symbols from httpd...(no debugging symbols found)...done.
> (gdb) run -X -e debug -k start
> Starting program: /usr/sbin/httpd -X -e debug -k start
> warning: Unable to find libthread_db matching inferior's thread
> library, thread debugging will not be available.
> [Tue Mar 01 08:13:03.030657 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module authn_file_module from
> /usr/lib/apache2/modules/mod_authn_file.so
> [Tue Mar 01 08:13:03.079515 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module authn_core_module from
> /usr/lib/apache2/modules/mod_authn_core.so
> [Tue Mar 01 08:13:03.132191 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module authz_host_module from
> /usr/lib/apache2/modules/mod_authz_host.so
> [Tue Mar 01 08:13:03.184107 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module authz_groupfile_module from
> /usr/lib/apache2/modules/mod_authz_groupfile.so
> [Tue Mar 01 08:13:03.234788 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module authz_user_module from
> /usr/lib/apache2/modules/mod_authz_user.so
> [Tue Mar 01 08:13:03.291208 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module authz_core_module from
> /usr/lib/apache2/modules/mod_authz_core.so
> [Tue Mar 01 08:13:03.346248 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module access_compat_module from
> /usr/lib/apache2/modules/mod_access_compat.so
> [Tue Mar 01 08:13:03.403987 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module auth_basic_module from
> /usr/lib/apache2/modules/mod_auth_basic.so
> [Tue Mar 01 08:13:03.462869 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module socache_shmcb_module from
> /usr/lib/apache2/modules/mod_socache_shmcb.so
> [Tue Mar 01 08:13:03.524206 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module reqtimeout_module from
> /usr/lib/apache2/modules/mod_reqtimeout.so
> [Tue Mar 01 08:13:03.587161 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module filter_module from
> /usr/lib/apache2/modules/mod_filter.so
> [Tue Mar 01 08:13:03.670177 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module deflate_module from
> /usr/lib/apache2/modules/mod_deflate.so
> [Tue Mar 01 08:13:03.737604 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module mime_module from
> /usr/lib/apache2/modules/mod_mime.so
> [Tue Mar 01 08:13:03.811455 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module log_config_module from
> /usr/lib/apache2/modules/mod_log_config.so
> [Tue Mar 01 08:13:03.878182 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module env_module from
> /usr/lib/apache2/modules/mod_env.so
> [Tue Mar 01 08:13:03.952743 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module headers_module from
> /usr/lib/apache2/modules/mod_headers.so
> [Tue Mar 01 08:13:04.024100 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module setenvif_module from
> /usr/lib/apache2/modules/mod_setenvif.so
> [Tue Mar 01 08:13:04.096323 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module version_module from
> /usr/lib/apache2/modules/mod_version.so
> [Tue Mar 01 08:13:04.594068 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module nss_module from
> /usr/lib/apache2/modules/libmodnss.so
> [Tue Mar 01 08:13:04.687089 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module mpm_prefork_module from
> /usr/lib/apache2/modules/mod_mpm_prefork.so
> [Tue Mar 01 08:13:04.773117 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module unixd_module from
> /usr/lib/apache2/modules/mod_unixd.so
> [Tue Mar 01 08:13:04.862035 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module status_module from
> /usr/lib/apache2/modules/mod_status.so
> [Tue Mar 01 08:13:04.956650 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module autoindex_module from
> /usr/lib/apache2/modules/mod_autoindex.so
> [Tue Mar 01 08:13:05.046425 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module dir_module from
> /usr/lib/apache2/modules/mod_dir.so
> [Tue Mar 01 08:13:05.140571 2016] [so:debug] [pid 588] mod_so.c(266):
> AH01575: loaded module alias_module from
> /usr/lib/apache2/modules/mod_alias.so
> [58887.850679] TCP: request_sock_TCP: Possible SYN flooding on port
> 443. Dropping request.  Check SNMP counters.
> 
> Program received signal SIGSEGV, Segmentation fault.
> 0x76b366dc in ?? () from /usr/lib/libssl3.so
> (gdb) where
> #0  0x76b366dc in ?? () from /usr/lib/libssl3.so
> #1  0x769ac830 in PR_CallOnceWithArg () from /usr/lib/libnspr4.so
> #2  0x769ac830 in PR_CallOnceWithArg () from /usr/lib/libnspr4.so
> #3  0x76b359ac in ?? () from /usr/lib/libssl3.so
> Backtrace stopped: previous frame identical to this frame (corrupt stack?)
> (gdb)

Just an educated guess but looks like it is failing in a call to
ssl3_GetSessionTicketKeysPKCS11() which calls:

    if (PR_CallOnceWithArg(&generate_session_keys_once,
            ssl3_GenerateSessionTicketKeysPKCS11, ss) != PR_SUCCESS)
        return SECFailure;

Unfortunately the symbols are still missing from your build so its hard
to know why.

rob