Re: future of bytecode verifier

[Alexander Gladysh <agladysh@...>]

On Wed, Mar 4, 2009 at 9:58 PM, Luiz Henrique de Figueiredo
<lhf@tecgraf.puc-rio.br> wrote:
> Following several bytecode exploits found by the relentless Peter Cawley
> and others, we are considering dropping the bytecode verifier completely in
> Lua 5.2. It seems useless to make a promise that we can't seem to deliver
> without a much more complicated verifier than the current one, and possibly
> with the need for costly runtime checks as well.

I agree.

> Our impression is that applications that are open to running arbitrary Lua
> code provided by the user should avoid accepting precompiled scripts. So we
> think that adding a flag to load (the Lua function from the base library)
> to check for and reject precompiled scripts is enough for Lua-based apps
> to be able to reject precompiled scripts if they want to. We don't think
> anything else is needed in the C side, since you can always write you own
> lua_Reader function to reject precompiled scripts.

Perhaps a luaL_* convenience function?

Alexander.