1527688 – httpd 2.4.6-67 reload causes leak of semaphores

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Bug 1527688 - httpd 2.4.6-67 reload causes leak of semaphores

Summary: httpd 2.4.6-67 reload causes leak of semaphores

Keywords:
Status:	CLOSED INSUFFICIENT_DATA
Alias:	None
Product:	Red Hat Enterprise Linux 7
Classification:	Red Hat
Component:	httpd
Sub Component:
Version:	7.4
Hardware:	x86_64
OS:	Linux
Priority:	unspecified
Severity:	medium
Target Milestone:	rc
Target Release:	---
Assignee:	Luboš Uhliarik
QA Contact:	BaseOS QE - Apps
Docs Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+	depends on / blocked

Reported:	2017-12-19 22:34 UTC by apircalabu
Modified:	2019-06-27 15:49 UTC (History)
CC List:	8 users (show)
Fixed In Version:
Doc Type:	If docs needed, set a value
Doc Text:
Clone Of:	1410883
Environment:
Last Closed:	2019-06-27 15:49:54 UTC
Target Upstream Version:
Embargoed:

Attachments	(Terms of Use)

Description apircalabu 2017-12-19 22:34:52 UTC

+++ This bug was initially created as a clone of Bug #1410883 +++

Seeing the same semaphore leak on multiple CentOS 7.4 shared hosting servers running httpd-2.4.6-67.el7.centos.6.x86_64

How to reproduce:

( ipcs -s | grep apache | wc -l ) ; ( for i in `seq 10` ; do httpd -k graceful ; sleep 1 ; echo -n "$i " ; done ) ; echo ; ( ipcs -s | grep apache | wc -l )
54
1 2 3 4 5 6 7 8 9 10 
59

httpd -V
Server version: Apache/2.4.6 (CentOS)
Server built:   Oct 19 2017 20:39:16
Server's Module Magic Number: 20120211:24
Server loaded:  APR 1.4.8, APR-UTIL 1.5.2
Compiled using: APR 1.4.8, APR-UTIL 1.5.2
Architecture:   64-bit
Server MPM:     prefork
  threaded:     no
    forked:     yes (variable process count)
Server compiled with....
 -D APR_HAS_SENDFILE
 -D APR_HAS_MMAP
 -D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
 -D APR_USE_SYSVSEM_SERIALIZE
 -D APR_USE_PTHREAD_SERIALIZE
 -D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
 -D APR_HAS_OTHER_CHILD
 -D AP_HAVE_RELIABLE_PIPED_LOGS
 -D DYNAMIC_MODULE_LIMIT=256
 -D HTTPD_ROOT="/etc/httpd"
 -D SUEXEC_BIN="/usr/sbin/suexec"
 -D DEFAULT_PIDLOG="/run/httpd/httpd.pid"
 -D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
 -D DEFAULT_ERRORLOG="logs/error_log"
 -D AP_TYPES_CONFIG_FILE="conf/mime.types"
 -D SERVER_CONFIG_FILE="conf/httpd.conf"

httpd -DDUMP_MODULES
Loaded Modules:
 core_module (static)
 so_module (static)
 http_module (static)
 access_compat_module (shared)
 actions_module (shared)
 alias_module (shared)
 allowmethods_module (shared)
 auth_basic_module (shared)
 auth_digest_module (shared)
 authn_anon_module (shared)
 authn_core_module (shared)
 authn_dbd_module (shared)
 authn_dbm_module (shared)
 authn_file_module (shared)
 authn_socache_module (shared)
 authz_core_module (shared)
 authz_dbd_module (shared)
 authz_dbm_module (shared)
 authz_groupfile_module (shared)
 authz_host_module (shared)
 authz_owner_module (shared)
 authz_user_module (shared)
 autoindex_module (shared)
 cache_module (shared)
 cache_disk_module (shared)
 data_module (shared)
 dbd_module (shared)
 deflate_module (shared)
 dir_module (shared)
 dumpio_module (shared)
 echo_module (shared)
 env_module (shared)
 expires_module (shared)
 ext_filter_module (shared)
 filter_module (shared)
 headers_module (shared)
 include_module (shared)
 info_module (shared)
 log_config_module (shared)
 logio_module (shared)
 mime_magic_module (shared)
 mime_module (shared)
 negotiation_module (shared)
 remoteip_module (shared)
 reqtimeout_module (shared)
 rewrite_module (shared)
 setenvif_module (shared)
 slotmem_plain_module (shared)
 slotmem_shm_module (shared)
 socache_dbm_module (shared)
 socache_memcache_module (shared)
 socache_shmcb_module (shared)
 status_module (shared)
 substitute_module (shared)
 suexec_module (shared)
 unique_id_module (shared)
 unixd_module (shared)
 userdir_module (shared)
 version_module (shared)
 vhost_alias_module (shared)
 dav_module (shared)
 dav_fs_module (shared)
 dav_lock_module (shared)
 lua_module (shared)
 mpm_prefork_module (shared)
 proxy_module (shared)
 lbmethod_bybusyness_module (shared)
 lbmethod_byrequests_module (shared)
 lbmethod_bytraffic_module (shared)
 lbmethod_heartbeat_module (shared)
 proxy_ajp_module (shared)
 proxy_balancer_module (shared)
 proxy_connect_module (shared)
 proxy_express_module (shared)
 proxy_fcgi_module (shared)
 proxy_fdpass_module (shared)
 proxy_ftp_module (shared)
 proxy_http_module (shared)
 proxy_scgi_module (shared)
 proxy_wstunnel_module (shared)
 ssl_module (shared)
 systemd_module (shared)
 cgi_module (shared)
 php5_module (shared)
 aclr_module (shared)
 cloudflare_module (shared)
 fcgid_module (shared)
 passenger_module (shared)
 sysenv_module (shared)

Comment 2 Joe Orton 2018-02-23 09:54:21 UTC

The bug referenced is specific to mod_proxy_hcheck/mod_watchdog, which are not loaded in your configuration.

Thank you for taking the time to report this issue to us. We appreciate the feedback and use reports such as this one to guide our efforts at improving our products. That being said, this bug tracking system is not a mechanism for requesting support, and we are not able to guarantee the timeliness or suitability of a resolution.

If this issue is critical or in any way time sensitive, please raise a ticket through the regular Red Hat support channels to ensure it receives the proper attention and prioritization to assure a timely resolution. 

For information on how to contact the Red Hat production support team, please visit:
    https://www.redhat.com/support/process/production/#howto

Comment 5 Joe Orton 2019-06-27 15:49:54 UTC

There are also multiple third-party modules reported.  If you can reproduce on RHEL with RHEL packages, please file a support ticket.

 cloudflare_module (shared)
 fcgid_module (shared)
 passenger_module (shared)

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