Re: Thoughts on lua_checkstack() implicit usage

[Peng Zhicheng <pengzhicheng1986@...>]

于 2011年10月21日 23:29, Rebel Neurofog 写道:
> > The problem comes with implicit stack usage by calls like luaL_ref() (and others I presume).
> As for me, luaL_checkstack () bothers me the most.
> This function is supposed to grow extra stack space or throw error if
> stack can't grow anymore.
> And so it does: it calls luaL_error () which seems to use additional
> stack space WITHOUT checking extra space.
> Sounds like major security issue.
> Do I miss something?

lLua reserved some stack slots for common internal use.
grep `EXTRA_STACK' from the source code, you will find it.