BUG/MINOR: hlua: Fix memory leaks on error path when registering a task

When an error occurred in hlua_register_task(), the allocated lua context
and task must be released to avoid memory leaks.

This patch may be backported in all stable versions.

diff --git a/src/hlua.c b/src/hlua.c
index c147fc3752657dbfc6959235f554ac5523e506fd..660c967074cdd3bb849051dc1e698e1e53e17d39 100644 (file)
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -6402,8 +6402,8 @@ __LJMP static int hlua_register_init(lua_State *L)
  */
 static int hlua_register_task(lua_State *L)
 {
-       struct hlua *hlua;
-       struct task *task;
+       struct hlua *hlua = NULL;
+       struct task *task = NULL;
        int ref;
        int state_id;
 
@@ -6424,7 +6424,7 @@ static int hlua_register_task(lua_State *L)
 
        hlua = pool_alloc(pool_head_hlua);
        if (!hlua)
-               WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+               goto alloc_error;
        HLUA_INIT(hlua);
 
        /* We are in the common lua state, execute the task anywhere,
@@ -6435,13 +6435,13 @@ static int hlua_register_task(lua_State *L)
        else
                task = task_new(tid_bit);
        if (!task)
-               WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+               goto alloc_error;
 
        task->context = hlua;
        task->process = hlua_process_task;
 
        if (!hlua_ctx_init(hlua, state_id, task, 1))
-               WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+               goto alloc_error;
 
        /* Restore the function in the stack. */
        lua_rawgeti(hlua->T, LUA_REGISTRYINDEX, ref);
@@ -6451,6 +6451,12 @@ static int hlua_register_task(lua_State *L)
        task_schedule(task, now_ms);
 
        return 0;
+
+  alloc_error:
+       task_destroy(task);
+       hlua_ctx_destroy(hlua);
+       WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+       return 0; /* Never reached */
 }
 
 /* Wrapper called by HAProxy to execute an LUA converter. This wrapper