From 134950dc97803dec941651fc12063cc630f609f1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20Chlup?= <vchlup@redhat.com>
Date: Thu, 21 Nov 2024 10:03:35 +0100
Subject: [PATCH] Fix missing locking when using mod_proxy_balancer

ref #235
---
 native/balancers/mod_lbmethod_cluster.c | 4 ++++
 native/mod_manager/mod_manager.c        | 9 ++++++---
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/native/balancers/mod_lbmethod_cluster.c b/native/balancers/mod_lbmethod_cluster.c
index 25327378..bda7ab36 100644
--- a/native/balancers/mod_lbmethod_cluster.c
+++ b/native/balancers/mod_lbmethod_cluster.c
@@ -93,7 +93,9 @@ static proxy_worker *find_best(proxy_balancer *balancer, request_rec *r)
         node_table = read_node_table(r->pool, node_storage, 0);
     }
 
+    node_storage->lock_nodes();
     mycandidate = internal_find_best_byrequests(r, balancer, vhost_table, context_table, node_table);
+    node_storage->unlock_nodes();
 
     return mycandidate;
 }
@@ -321,7 +323,9 @@ static apr_status_t mc_watchdog_callback(int state, void *data, apr_pool_t *pool
             }
 
             /* cleanup removed node in shared memory */
+            node_storage->lock_nodes();
             remove_removed_node(s, pool, now, node_table);
+            node_storage->unlock_nodes();
         }
         break;
 
diff --git a/native/mod_manager/mod_manager.c b/native/mod_manager/mod_manager.c
index b6837deb..a391f939 100644
--- a/native/mod_manager/mod_manager.c
+++ b/native/mod_manager/mod_manager.c
@@ -935,7 +935,10 @@ static apr_status_t mod_manager_manage_worker(request_rec *r, const nodeinfo_t *
     apr_table_set(params, "b_wyes", "1");
     apr_table_set(params, "b_nwrkr",
                   apr_pstrcat(r->pool, node->mess.Type, "://", node->mess.Host, ":", node->mess.Port, NULL));
-    balancer_manage(r, params);
+    rv = balancer_manage(r, params);
+    if (rv != APR_SUCCESS) {
+        return rv;
+    }
     apr_table_clear(params);
 
     /* now process the worker */
@@ -1572,7 +1575,6 @@ static char *process_config(request_rec *r, char **ptr, int *errtype)
     /* Insert the Alias and corresponding Context */
     phost = vhost;
     if (phost->host == NULL && phost->context == NULL) {
-        loc_unlock_nodes();
         /* if using mod_balancer create or update the worker */
         if (balancer_manage) {
             apr_status_t rv = mod_manager_manage_worker(r, &nodeinfo, &balancerinfo);
@@ -1580,6 +1582,7 @@ static char *process_config(request_rec *r, char **ptr, int *errtype)
         } else {
             ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "process_config: NO balancer-manager");
         }
+        loc_unlock_nodes();
         return NULL; /* Alias and Context missing */
     }
     while (phost) {
@@ -1594,7 +1597,6 @@ static char *process_config(request_rec *r, char **ptr, int *errtype)
         phost = phost->next;
         vid++;
     }
-    loc_unlock_nodes();
 
     /* if using mod_balancer create or update the worker */
     if (balancer_manage) {
@@ -1603,6 +1605,7 @@ static char *process_config(request_rec *r, char **ptr, int *errtype)
     } else {
         ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "process_config: NO balancer-manager");
     }
+    loc_unlock_nodes();
 
     ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "process_config: Done");