Re: 2nd Linux kernel patch to remove stack exec

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Bryan Reece <reece@TAZ.NCEYE.NET> wrote:

> Wouldn't it be a better idea to patch crt0 and the function entry and
> exit code to generate a magic cookie a word or so long at startup,
> write this cookie just below the return address on entry, and test it
> before returning, dying horribly if it's not correct anymore?

No -- this is far too expensive. The other proposal has the advantage
of not slowing down all applications and of not requiring recompilation.

Andreas.

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