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Re:Intel Analysis of Speculative Execution Side Channels [pdf] by bogomipz on Friday January 05, 2018 @03:11PM (#16081248)
Section 2.2.1 states:

>"An attacker discovers or causes the creation of ‘confused deputy’ code which allows the attacker to cause speculative operations to reveal information not normally accessible to the attacker."

Can someone say what ‘confused deputy’ code means here? This is not a term I have ever come across before.

The authors then go on to state:

>"If the attacker can identify an appropriate ‘confused deputy’ in a more privileged level, the attackermay be able to exploit that deputy in order to deduce the contents of memory accessible to that deputy but not to the attacker."

Here the reference is to an "appropriate 'confused deputy.' Are these just weasel words? Can someone shed some light on "confused deputies" and what makes one "appropriate"?

Re:Intel Analysis of Speculative Execution Side Channels [pdf] by detaro on Friday January 05, 2018 @03:16PM (#16081287)
https://en.wikipedia.org/wiki/Confused_deputy_problem

That said, I don't think it's good label for what's going on.

Re:Intel Analysis of Speculative Execution Side Channels [pdf] by tlb on Friday January 05, 2018 @03:26PM (#16081369)
It's sort of victim blaming. The code is wrong for having instructions corresponding to a[*b] anywhere in it, rather than our processor is wrong by speculatively executing them with visible effects.
Re:Intel Analysis of Speculative Execution Side Channels [pdf] by fyi1183 on Saturday January 06, 2018 @03:32AM (#16084401)
Those visible effects (caches being primed by speculative execution) are desirable in many cases though, so it's misleading to say the processor is wrong.
Re:Intel Analysis of Speculative Execution Side Channels [pdf] by bogomipz on Friday January 05, 2018 @03:28PM (#16081387)
Thanks, yes agreed, this sounds like a willfully misplaced label.