Re: what is the role of the `seed` field in the Lua global state?

[云风 Cloud Wu <cloudwu@...>]

Roberto Ierusalimschy <roberto@inf.puc-rio.br> 于2020年3月11日周三 下午8:57写道：
>
> > > What does this seed accomplish?  What problem does it solve?
> > >
> >
> > I suspect it is related to this:
> > https://stackoverflow.com/questions/9241230/what-is-murmurhash3-seed-parameter/9241429#9241429
> >
> > attackers may use the properties of a hash function to construct a denial
> > > of service attack. They could do this by providing strings to your hash
> > > function that all hash to the same value destroying the performance of your
> > > hash table. But if you use a different seed for each run of your program,
> > > the set of strings the attackers must use changes.
>
> Exactly.
>
> -- Roberto
>

Is there any way to specify a seed when I create a new lua VM ? It's
very useful for reproduction of bugs .
If the seed is always random, the order of table iteration would be
different every time.

I wish you can add a new api to create a lua VM with a seed in future.

-- 
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