Path from Jeff Trawick:

> Attached is a patch to trunk that allows you to hook in to the stat
> calls from directory walk.  Call apr_stat() like core_dirwalk_stat()
> but check for APR_STATUS_IS_EACCES(rv) and decide whether to run
> lingering close and exit.  Let us know how that goes.

Backported to Apache 2.4.2.

Index: httpd-2.4.2/server/core.c
===================================================================
--- httpd-2.4.2.orig/server/core.c
+++ httpd-2.4.2/server/core.c
@@ -4779,6 +4779,12 @@ static apr_status_t core_insert_network_
     return APR_SUCCESS;
 }
 
+static apr_status_t core_dirwalk_stat(apr_finfo_t *finfo, request_rec *r,
+                                      apr_int32_t wanted) 
+{
+    return apr_stat(finfo, r->filename, wanted, r->pool);
+}
+
 static void core_dump_config(apr_pool_t *p, server_rec *s)
 {
     core_server_config *sconf = ap_get_core_module_config(s->module_config);
@@ -4855,7 +4861,8 @@ static void register_hooks(apr_pool_t *p
     ap_hook_child_status(ap_core_child_status, NULL, NULL, APR_HOOK_MIDDLE);
     ap_hook_insert_network_bucket(core_insert_network_bucket, NULL, NULL,
                                   APR_HOOK_REALLY_LAST);
-
+    ap_hook_dirwalk_stat(core_dirwalk_stat, NULL, NULL, APR_HOOK_REALLY_LAST);
+    
     /* register the core's insert_filter hook and register core-provided
      * filters
      */
Index: httpd-2.4.2/server/request.c
===================================================================
--- httpd-2.4.2.orig/server/request.c
+++ httpd-2.4.2/server/request.c
@@ -70,6 +70,7 @@ APR_HOOK_STRUCT(
     APR_HOOK_LINK(insert_filter)
     APR_HOOK_LINK(create_request)
     APR_HOOK_LINK(post_perdir_config)
+    APR_HOOK_LINK(dirwalk_stat)
 )
 
 AP_IMPLEMENT_HOOK_RUN_FIRST(int,translate_name,
@@ -91,6 +92,9 @@ AP_IMPLEMENT_HOOK_RUN_FIRST(int,auth_che
 AP_IMPLEMENT_HOOK_VOID(insert_filter, (request_rec *r), (r))
 AP_IMPLEMENT_HOOK_RUN_ALL(int, create_request,
                           (request_rec *r), (r), OK, DECLINED)
+AP_IMPLEMENT_HOOK_RUN_FIRST(apr_status_t,dirwalk_stat,
+                            (apr_finfo_t *finfo, request_rec *r, apr_int32_t wanted),
+                            (finfo, r, wanted), AP_DECLINED)
 
 /**
  * This hook allows modules to affect the request immediately after the
@@ -621,7 +625,7 @@ AP_DECLARE(int) ap_directory_walk(reques
      * with APR_ENOENT, knowing that the path is good.
      */
     if (r->finfo.filetype == APR_NOFILE || r->finfo.filetype == APR_LNK) {
-        rv = apr_stat(&r->finfo, r->filename, APR_FINFO_MIN, r->pool);
+        rv = ap_run_dirwalk_stat(&r->finfo, r, APR_FINFO_MIN);
 
         /* some OSs will return APR_SUCCESS/APR_REG if we stat
          * a regular file but we have '/' at the end of the name;
@@ -687,9 +691,8 @@ AP_DECLARE(int) ap_directory_walk(reques
              * check.
              */
             if (!(opts & OPT_SYM_LINKS)) {
-                rv = apr_stat(&thisinfo, r->filename,
-                              APR_FINFO_MIN | APR_FINFO_NAME | APR_FINFO_LINK,
-                              r->pool);
+                rv = ap_run_dirwalk_stat(&thisinfo, r,
+                                         APR_FINFO_MIN | APR_FINFO_NAME | APR_FINFO_LINK);
                 /*
                  * APR_INCOMPLETE is as fine as result as APR_SUCCESS as we
                  * have added APR_FINFO_NAME to the wanted parameter of
@@ -1104,9 +1107,8 @@ AP_DECLARE(int) ap_directory_walk(reques
              * the name of its target, if we are fixing the filename
              * case/resolving aliases.
              */
-            rv = apr_stat(&thisinfo, r->filename,
-                          APR_FINFO_MIN | APR_FINFO_NAME | APR_FINFO_LINK,
-                          r->pool);
+            rv = ap_run_dirwalk_stat(&thisinfo, r,
+                                     APR_FINFO_MIN | APR_FINFO_NAME | APR_FINFO_LINK);
 
             if (APR_STATUS_IS_ENOENT(rv)) {
                 /* Nothing?  That could be nice.  But our directory
Index: httpd-2.4.2/include/http_request.h
===================================================================
--- httpd-2.4.2.orig/include/http_request.h
+++ httpd-2.4.2/include/http_request.h
@@ -528,6 +528,15 @@ AP_DECLARE(void) ap_hook_check_authz(ap_
  */
 AP_DECLARE_HOOK(void,insert_filter,(request_rec *r))
 
+/**
+ * This hook allows modules to handle/emulate the apr_stat() calls
+ * needed for directory walk.
+ * @param r The current request
+ * @return apr_status_t or AP_DECLINED (let later modules decide)
+ * @ingroup hooks
+ */
+AP_DECLARE_HOOK(apr_status_t,dirwalk_stat,(apr_finfo_t *finfo, request_rec *r, apr_int32_t wanted))
+
 AP_DECLARE(int) ap_location_walk(request_rec *r);
 AP_DECLARE(int) ap_directory_walk(request_rec *r);
 AP_DECLARE(int) ap_file_walk(request_rec *r);