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A comment on Moving the Linux Kernel to Modern C. Parent comment

Re:Moving the Linux Kernel to Modern C by mwint on Thursday February 24, 2022 @04:05PM (#30460269)
What's a Ken Thompson attack?
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Re:Moving the Linux Kernel to Modern C by nl on Thursday February 24, 2022 @04:20PM (#30460452)
Ken Thompson's "cc hack" - Presented in the journal, Communication of the ACM, Vol. 27, No. 8, August 1984, in a paper entitled "Reflections on Trusting Trust", Ken Thompson, co-author of UNIX, recounted a story of how he created a version of the C compiler that, when presented with the source code for the "login" program, would automatically compile in a backdoor to allow him entry to the system.

https://www.win.tue.nl/~aeb/linux/hh/thompson/trust.html

The paper's a pretty entertaining read:

> First we compile the modified source with the normal C compiler to produce a bugged binary. We install this binary as the official C. We can now remove the bugs from the source of the compiler and the new binary will reinsert the bugs whenever it is compiled. Of course, the login command will remain bugged with no trace in source anywhere.

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Re:Moving the Linux Kernel to Modern C by febstar on Thursday February 24, 2022 @04:12PM (#30460351)
Most likely referring to "Reflections on Trusting Trust" [0]; i.e. when the compiler is itself the attack vector.

[0]: https://www.cs.cmu.edu/~rdriley/487/papers/Thompson_1984_Ref...

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Re:Moving the Linux Kernel to Modern C by Jtsummers on Thursday February 24, 2022 @04:10PM (#30460326)
https://www.cs.cmu.edu/~rdriley/487/papers/Thompson_1984_Ref...

Ken Thompson, Reflections on Trusting Trust.

EDIT: I don't think I've seen 5 nearly simultaneous replies sharing the same link before.

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Re:Moving the Linux Kernel to Modern C by ksec on Thursday February 24, 2022 @04:29PM (#30460549)
>EDIT: I don't think I've seen 5 nearly simultaneous replies sharing the same link before.

LOL I was searching for a non-PDF link and delayed the reply. It would have been 6 simultaneous answer.

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Re:Moving the Linux Kernel to Modern C by bombcar on Thursday February 24, 2022 @04:11PM (#30460334)
https://www.cs.cmu.edu/~rdriley/487/papers/Thompson_1984_Ref...

How do you prove your stack is secure?

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Re:Moving the Linux Kernel to Modern C by gmfawcett on Thursday February 24, 2022 @06:43PM (#30461925)
Solution: the compiler for the microlanguage at the bottom of the stack is none other than the kindly and incorruptible American film star, Tom Hanks.
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Re:Moving the Linux Kernel to Modern C by esarc on Thursday February 24, 2022 @04:13PM (#30460364)
https://www.cs.cmu.edu/~rdriley/487/papers/Thompson_1984_Ref...
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Re:Moving the Linux Kernel to Modern C by ksec on Thursday February 24, 2022 @04:25PM (#30460521)
Reflections on Trusting Trust - Ken Thompson

https://wiki.c2.com/?TheKenThompsonHack

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Re:Moving the Linux Kernel to Modern C by mindcrime on Thursday February 24, 2022 @04:11PM (#30460339)
I believe the person you are replying to is using that as an allusion to the issues discussed in the famous "Reflections on Trusting Trust" paper[1] by Ken Thompson.

[1]: https://www.cs.cmu.edu/~rdriley/487/papers/Thompson_1984_Ref...

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