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A comment on Inception: A simple XOR can cause a Microarchitectural Stack Overflow. Parent comment

Re:Inception: A simple XOR can cause a Microarchitectural St... by colinsane on Wednesday August 09, 2023 @01:53AM (#37059146)
isn’t every attack based on speculative execution actually just an attack over shared mutable state? i.e., if the branch predictions, cache, and so on weren’t both shared and mutable, speculative execution wouldn’t be so problematic?
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Re:Inception: A simple XOR can cause a Microarchitectural St... by nine_k on Wednesday August 09, 2023 @02:03AM (#37059212)
Indeed. Not just shared, but shared across security domains, e.g. across OS processes, or across the kernel / userspace boundary.

Speculating within one security domain would not be problematic, because anything such speculation allows to glean is already accessible normally. This is sort of similar to having a single reference to a mutable object, which is also safe.

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