Re: illegal luaL_buffer usage in loadlib.c

[Russell Haley <russ.haley@...>]

On Wed, Dec 13, 2017 at 4:48 AM, Roberto Ierusalimschy
<roberto@inf.puc-rio.br> wrote:
>> > In findloader (https://www.lua.org/source/5.3/loadlib.c.html#findloader)
>> > luaL_buffinit is called before pushing the searchers table onto the
>> > stack.
>> > This breaks the "balanced stack" that luaL_buffinit is documented to expect.
>> > Also, later code then assumes that the searchers table is at index 3.
>> >
>> > Now, this doesn't actually manifest in a bug in PUC Rio lua 5.3, as
>> > the implementation of luaL_buffinit doesn't touch the stack.
>> > However if someone were to extract parts of loadlib.c to use with a
>> > different auxlib implementation then there might be issues.
>> >
>> > The fix is to simply move the luaL_buffinit call below the lua_getfield call.
>>
>> Thanks for the correction.
>
> BTW, 'searchpath' has the same issue. (The call to 'luaL_gsub' leaves
> a string on the stack.)
>
> -- Roberto
>

For my edification, if it *could* occur would this be considered a memory leak?

Russ