1 files changed, 55 insertions, 7 deletions

diff --git a/modules/ldap/util_ldap_cache_mgr.c b/modules/ldap/util_ldap_cache_mgr.c
index 56b8cbec..6bb066ab 100644
--- a/modules/ldap/util_ldap_cache_mgr.c
+++ b/modules/ldap/util_ldap_cache_mgr.c
@@ -385,6 +385,7 @@ void *util_ald_cache_fetch(util_ald_cache_t *cache, void *payload)
 void *util_ald_cache_insert(util_ald_cache_t *cache, void *payload)
 {
     unsigned long hashval;
+    void *tmp_payload;
     util_cache_node_t *node;
 
     /* sanity check */
@@ -397,21 +398,68 @@ void *util_ald_cache_insert(util_ald_cache_t *cache, void *payload)
         util_ald_cache_purge(cache);
         if (cache->numentries >= cache->maxentries) {
             /* if the purge was not effective, we leave now to avoid an overflow */
+            ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
+                         "Purge of LDAP cache failed");
             return NULL;
         }
     }
 
-    /* should be safe to add an entry */
-    if ((node = (util_cache_node_t *)util_ald_alloc(cache, sizeof(util_cache_node_t))) == NULL) {
-        return NULL;
+    node = (util_cache_node_t *)util_ald_alloc(cache,
+                                               sizeof(util_cache_node_t));
+    if (node == NULL) {
+        /*
+         * XXX: The cache management should be rewritten to work
+         * properly when LDAPSharedCacheSize is too small.
+         */
+        ap_log_error(APLOG_MARK, APLOG_WARNING, 0, NULL,
+                     "LDAPSharedCacheSize is too small. Increase it or "
+                     "reduce LDAPCacheEntries/LDAPOpCacheEntries!");
+        if (cache->numentries < cache->fullmark) {
+            /*
+             * We have not even reached fullmark, trigger a complete purge.
+             * This is still better than not being able to add new entries
+             * at all.
+             */
+            cache->marktime = apr_time_now();
+        }
+        util_ald_cache_purge(cache);
+        node = (util_cache_node_t *)util_ald_alloc(cache,
+                                                   sizeof(util_cache_node_t));
+        if (node == NULL) {
+            ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
+                         "Could not allocate memory for LDAP cache entry");
+            return NULL;
+        }
     }
 
     /* Take a copy of the payload before proceeeding. */
-    payload = (*cache->copy)(cache, payload);
-    if (!payload) {
-        util_ald_free(cache, node);
-        return NULL;
+    tmp_payload = (*cache->copy)(cache, payload);
+    if (tmp_payload == NULL) {
+        /*
+         * XXX: The cache management should be rewritten to work
+         * properly when LDAPSharedCacheSize is too small.
+         */
+        ap_log_error(APLOG_MARK, APLOG_WARNING, 0, NULL,
+                     "LDAPSharedCacheSize is too small. Increase it or "
+                     "reduce LDAPCacheEntries/LDAPOpCacheEntries!");
+        if (cache->numentries < cache->fullmark) {
+            /*
+             * We have not even reached fullmark, trigger a complete purge.
+             * This is still better than not being able to add new entries
+             * at all.
+             */
+            cache->marktime = apr_time_now();
+        }
+        util_ald_cache_purge(cache);
+        tmp_payload = (*cache->copy)(cache, payload);
+        if (tmp_payload == NULL) {
+            ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
+                         "Could not allocate memory for LDAP cache value");
+            util_ald_free(cache, node);
+            return NULL;
+        }
     }
+    payload = tmp_payload;
 
     /* populate the entry */
     cache->inserts++;