Possible NULL pointer dereference on Lua_LLThread__delete__meth?? #14
Description
Dear developers:
Our static analysis tool reports an NPD bug here, since this_idx1 may be null. It may be a false positive. Thank yo for your confirmation.
lua-llthreads/src/pre_generated-llthreads.nobj.c
Line 1788 in 8dcf387
static int Lua_LLThread__delete__meth(lua_State *L) {
int this_flags_idx1 = 0;
Lua_LLThread * this_idx1;
Lua_LLThread_child *child;
this_idx1 = obj_type_Lua_LLThread_delete(L,1,&(this_flags_idx1)); //execute obj_udata_luadelete_weak which may return null.
if(!(this_flags_idx1 & OBJ_UDATA_FLAG_OWN)) { return 0; }
/* if the thread has been started and has not been detached/joined. */
if((this_idx1->state & TSTATE_STARTED) == TSTATE_STARTED &&
(this_idx1->state & (TSTATE_DETACHED|TSTATE_JOINED)) == 0) {
...;
}
llthread_destroy(this_idx1);
return 0;
}
This method may return NULL.
static FUNC_UNUSED void *obj_udata_luadelete_weak(lua_State *L, int _index, obj_type *type, int *flags) {
void *obj;
obj_udata *ud = obj_udata_luacheck_internal(L, _index, &(obj), type, 0);
if(ud == NULL) return NULL;
*flags = ud->flags;
/* null userdata. */
ud->obj = NULL;
ud->flags = 0;
/* clear the metatable in invalidate userdata. */
lua_pushnil(L);
lua_setmetatable(L, _index);
/* get objects weak table. */
lua_pushlightuserdata(L, obj_udata_weak_ref_key);
lua_rawget(L, LUA_REGISTRYINDEX); /* weak ref table. */
/* remove object from weak table. */
lua_pushlightuserdata(L, obj);
lua_pushnil(L);
lua_rawset(L, -3);
return obj;
}