[CritFix] Fix race condition in checking of cached maps

diff --git a/src/libutil/map.c b/src/libutil/map.c
index 689f1b0c476b1d655f700a0ff637ba7fff1e896d..a1539525b21ad8383a07b33b55db24f5f2baec41 100644 (file)
--- a/src/libutil/map.c
+++ b/src/libutil/map.c
@@ -318,9 +318,12 @@ static void
 rspamd_map_cache_cb (gint fd, short what, gpointer ud)
 {
        struct rspamd_http_map_cached_cbdata *cache_cbd = ud;
+       struct rspamd_map *map;
 
-       g_atomic_int_set (&cache_cbd->map->cache->available, 0);
+       map = cache_cbd->map;
+       g_atomic_int_set (&map->cache->available, 0);
        MAP_RELEASE (cache_cbd->shm, "rspamd_http_map_cached_cbdata");
+       msg_debug_map ("cached data is now expired now for %s", map->name);
        event_del (&cache_cbd->timeout);
        g_slice_free1 (sizeof (*cache_cbd), cache_cbd);
 }
@@ -477,7 +480,8 @@ read_data:
                        goto err;
                }
 
-               msg_info_map ("read map data from %s", cbd->data->host);
+               msg_info_map ("read map data from %s (%z bytes)", cbd->data->host,
+                               dlen);
                map->read_callback (in, cbd->data_len, &cbd->periodic->cbdata, TRUE);
 
                /*
@@ -602,6 +606,7 @@ rspamd_map_periodic_dtor (struct map_periodic_cbdata *periodic)
        if (periodic->locked) {
                rspamd_map_schedule_periodic (periodic->map, FALSE, FALSE, FALSE);
                g_atomic_int_set (periodic->map->locked, 0);
+               msg_debug_map ("unlocked map");
        }
 
        g_slice_free1 (sizeof (*periodic), periodic);
@@ -720,16 +725,21 @@ rspamd_map_read_cached (struct rspamd_map *map,
        in = rspamd_shmem_xmap (map->cache->shmem_name, PROT_READ, &len);
 
        if (in == NULL) {
+               msg_err ("cannot map cache from %s: %s", map->cache->shmem_name,
+                               strerror (errno));
                return FALSE;
        }
 
        if (len < map->cache->len) {
+               msg_err ("cannot map cache from %s: bad length %z, %z expected",
+                               map->cache->shmem_name,
+                               len, map->cache->len);
                munmap (in, len);
                return FALSE;
        }
 
        map->read_callback (in, map->cache->len, &periodic->cbdata, TRUE);
-       msg_info_map ("read map data from %s (cached)", host);
+       msg_info_map ("read map data from %s (cached) (%z bytes)", host, len);
        munmap (in, len);
 
        return TRUE;
@@ -757,14 +767,19 @@ rspamd_map_common_http_callback (struct rspamd_map *map, struct rspamd_map_backe
                                periodic->cur_backend = 0;
                                rspamd_map_periodic_callback (-1, EV_TIMEOUT, periodic);
                        }
+                       else {
+                               /* Switch to the next backend */
+                               periodic->cur_backend ++;
+                               rspamd_map_periodic_callback (-1, EV_TIMEOUT, periodic);
+                       }
 
                        return;
                }
                else if (rspamd_map_read_cached (map, periodic, data->host)) {
                        /* Switch to the next backend */
                        periodic->cur_backend ++;
-                       rspamd_map_periodic_callback (-1, EV_TIMEOUT, periodic);
                        data->last_checked = map->cache->last_checked;
+                       rspamd_map_periodic_callback (-1, EV_TIMEOUT, periodic);
 
                        return;
                }
@@ -835,7 +850,6 @@ rspamd_map_common_http_callback (struct rspamd_map *map, struct rspamd_map_backe
                cbd->periodic->errored = TRUE;
        }
 
-       /* We don't need own ref as it is now ref counted by DNS handlers */
        MAP_RELEASE (cbd, "http_callback_data");
 }
 
@@ -941,6 +955,7 @@ rspamd_map_periodic_callback (gint fd, short what, void *ud)
                        return;
                }
                else {
+                       msg_debug_map ("locked map");
                        cbd->locked = TRUE;
                }
        }
@@ -952,6 +967,8 @@ rspamd_map_periodic_callback (gint fd, short what, void *ud)
                if (cbd->locked) {
                        g_atomic_int_set (cbd->map->locked, 0);
                }
+
+               msg_debug_map ("unlocked map");
                MAP_RELEASE (cbd, "periodic");
 
                return;
@@ -960,6 +977,8 @@ rspamd_map_periodic_callback (gint fd, short what, void *ud)
        /* For each backend we need to check for modifications */
        if (cbd->cur_backend >= cbd->map->backends->len) {
                /* Last backend */
+               msg_debug_map ("finished map: %d of %d", cbd->cur_backend,
+                               cbd->map->backends->len);
                MAP_RELEASE (cbd, "periodic");
 
                return;