On Tue, 2010-07-06 at 10:50 +0200, Ondřej Surý wrote:
> I am a author of mod-vhost-ldap module and I have received complaints
> about DocumentRoot being unstable. After a fixing of dozen bugs and
> further debugging I have found out, that DocumentRoot is shared per
> process and not per thread and thus I am unable to fix that as a
> self-contained fix, since ap_document_root gets overwritten under a
> heavy load.
FWIW, when I ran into this problem in mod-vhost-ldap, I fixed it by
making a copy of the entire server_rec structure in the request pool.
My mod-vhost-ldap patch is below.
Anders
-- 8< --
>From ac2bea6ec55c4991667420d5bf503e82abd16e80 Mon Sep 17 00:00:00 2001
From: Anders Kaseorg <ande...@mit.edu>
Date: Fri, 12 Feb 2010 07:47:59 +0000
Subject: [PATCH] Copy the server_rec instead of corrupting it in place.
Signed-off-by: Anders Kaseorg <ande...@mit.edu>
---
mod_vhost_ldap.c | 32 +++++++++++++++++++++++++++-----
1 files changed, 27 insertions(+), 5 deletions(-)
diff --git a/mod_vhost_ldap.c b/mod_vhost_ldap.c
index f3b729a..ff53d11 100644
--- a/mod_vhost_ldap.c
+++ b/mod_vhost_ldap.c
@@ -94,6 +94,8 @@ typedef struct mod_vhost_ldap_request_t {
char *attributes[] =
{ "apacheServerName", "apacheDocumentRoot", "apacheScriptAlias",
"apacheSuexecUid", "apacheSuexecGid", "apacheServerAdmin", 0 };
+static int total_modules;
+
#if (APR_MAJOR_VERSION >= 1)
static APR_OPTIONAL_FN_TYPE(uldap_connection_close)
*util_ldap_connection_close;
static APR_OPTIONAL_FN_TYPE(uldap_connection_find) *util_ldap_connection_find;
@@ -117,6 +119,13 @@ static void ImportULDAPOptFn(void)
static int mod_vhost_ldap_post_config(apr_pool_t *p, apr_pool_t *plog,
apr_pool_t *ptemp, server_rec *s)
{
+ module **m;
+
+ /* Stolen from modules/generators/mod_cgid.c */
+ total_modules = 0;
+ for (m = ap_preloaded_modules; *m != NULL; m++)
+ total_modules++;
+
/* make sure that mod_ldap (util_ldap) is loaded */
if (ap_find_linked_module("util_ldap.c") == NULL) {
ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, s,
@@ -421,7 +430,6 @@ command_rec mod_vhost_ldap_cmds[] = {
#define FILTER_LENGTH MAX_STRING_LEN
static int mod_vhost_ldap_translate_name(request_rec *r)
{
- request_rec *top = (r->main)?r->main:r;
mod_vhost_ldap_request_t *reqc;
apr_table_t *e;
int failures = 0;
@@ -575,17 +583,31 @@ fallback:
return DECLINED;
}
- top->server->server_hostname = apr_pstrdup (top->pool, reqc->name);
+ if ((r->server = apr_pmemdup(r->pool, r->server,
+ sizeof(*r->server))) == NULL)
+ return HTTP_INTERNAL_SERVER_ERROR;
+
+ r->server->server_hostname = reqc->name;
if (reqc->admin) {
- top->server->server_admin = apr_pstrdup (top->pool, reqc->admin);
+ r->server->server_admin = reqc->admin;
}
// set environment variables
- e = top->subprocess_env;
+ e = r->subprocess_env;
apr_table_addn (e, "SERVER_ROOT", reqc->docroot);
- core->ap_document_root = apr_pstrdup(top->pool, reqc->docroot);
+ if ((r->server->module_config =
+ apr_pmemdup(r->pool, r->server->module_config,
+ sizeof(void *) *
+ (total_modules + DYNAMIC_MODULE_LIMIT))) == NULL)
+ return HTTP_INTERNAL_SERVER_ERROR;
+
+ if ((core = apr_pmemdup(r->pool, core, sizeof(*core))) == NULL)
+ return HTTP_INTERNAL_SERVER_ERROR;
+ ap_set_module_config(r->server->module_config, &core_module, core);
+
+ core->ap_document_root = reqc->docroot;
ap_log_rerror(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r,
"[mod_vhost_ldap.c]: translated to %s", r->filename);
--
1.7.1.1
