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From: Stefan Monnier <monnier@iro.umontreal.ca>
Newsgroups: comp.arch
Subject: Re: Constant Stack Canaries
Date: Tue, 01 Apr 2025 22:55:56 -0400
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>> Say, if you load a single copy of a binary at 0x24680000.
>> Process A and B can't use the same mapping in the same address space,
>> with PC-rel globals, as then they would each see the other's globals.
>
> Say I load a copy of the binary text at 0x24680000 and its data at
> 0x35900000 for a distance of 0x11280000 into the address space of
> a process.
>
> Then I load another copy at 0x44680000 and its data at 55900000
> into the address space of a different process.

But then if thread A (whose state is stored at 0x35900000) sends to
thread B (whose state is at 55900000) a closure whose code points
somewhere inside 0x24680000, it will end up using the state of thread
A instead of the state of the current thread.


        Stefan