[sr-dev] git:4.3:3181001e: dialog: fix race due to deep copy of dlg hash table slot when saving to db

[Daniel-Constantin Mierla]

Module: kamailio
Branch: 4.3
Commit: 3181001ebae49847ed210428946fde96e89e9c4f
URL: https://github.com/kamailio/kamailio/commit/3181001ebae49847ed210428946fde96e89e9c4f

Author: Daniel-Constantin Mierla <miconda at gmail.com>
Committer: Daniel-Constantin Mierla <miconda at gmail.com>
Date: 2015-10-02T14:11:05+02:00

dialog: fix race due to deep copy of dlg hash table slot when saving to db

(cherry picked from commit 2d9c7f9658fe78979df69c81f56b36366b80a262)

---

Modified: modules/dialog/dlg_db_handler.c

---

Diff:  https://github.com/kamailio/kamailio/commit/3181001ebae49847ed210428946fde96e89e9c4f.diff
Patch: https://github.com/kamailio/kamailio/commit/3181001ebae49847ed210428946fde96e89e9c4f.patch

---

diff --git a/modules/dialog/dlg_db_handler.c b/modules/dialog/dlg_db_handler.c
index 5dddd63..aed40e7 100644
--- a/modules/dialog/dlg_db_handler.c
+++ b/modules/dialog/dlg_db_handler.c
@@ -862,43 +862,31 @@ int update_dialog_dbinfo_unsafe(struct dlg_cell * cell)
 
 int update_dialog_dbinfo(struct dlg_cell * cell)
 {
-	struct dlg_entry entry;
 	/* lock the entry */
-	entry = (d_table->entries)[cell->h_entry];
-	dlg_lock( d_table, &entry);
+	dlg_lock(d_table, &d_table->entries[cell->h_entry]);
 	if (update_dialog_dbinfo_unsafe(cell) != 0) {
-		dlg_unlock( d_table, &entry);
+		dlg_unlock(d_table, &d_table->entries[cell->h_entry]);
 		return -1;
 	} 
-	dlg_unlock( d_table, &entry);
+	dlg_unlock(d_table, &d_table->entries[cell->h_entry]);
 	return 0;
 }
 
 void dialog_update_db(unsigned int ticks, void * param)
 {
-	int index;
-	struct dlg_entry entry;
-	struct dlg_cell  * cell; 
+	int i;
+	struct dlg_cell *cell;
 
 	LM_DBG("saving current_info \n");
-	
-	for(index = 0; index< d_table->size; index++){
-		/* lock the whole entry */
-		entry = (d_table->entries)[index];
-		dlg_lock( d_table, &entry);
-
-		for(cell = entry.first; cell != NULL; cell = cell->next){
-			if (update_dialog_dbinfo_unsafe(cell) != 0) {
-				dlg_unlock( d_table, &entry);
-				goto error;
-			}
-		}
-		dlg_unlock( d_table, &entry);
 
+	for(i = 0; i < d_table->size; i++){
+		/* lock the slot */
+		dlg_lock(d_table, &d_table->entries[i]);
+		for(cell = d_table->entries[i].first; cell != NULL; cell = cell->next){
+			/* if update fails for one dlg, still do it for the next ones */
+			update_dialog_dbinfo_unsafe(cell);
+		}
+		dlg_unlock(d_table, &d_table->entries[i]);
 	}
-
 	return;
-
-error:
-	dlg_unlock( d_table, &entry);
 }