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I don't understand, isn't this pointless? I could just change some other data structure or variable, hell, I'll just change the sudo input buffer size and do a stack overflow, or a memcpy size into a heap overflow, or what stops me changing a jne (Jump if Not Equal) instruction to a jg (Jump if Greater) and bypassing the if's?

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I'd argue its worse than pointless, at best it does nothing and at worse it seems to make the code harder to understand and audit, which could result in more future vulnerabilities.

The associated paper abstract claims to have broken sudo by rowhammering register values. It stands to reason that these mitigations thwart the found attacks - the commit message points to the paper as the reason for these mitigations, after all.

Preventing known attacks is not pointless at all.

I think the point is that if your known attack I'd "target was shot in the right hand" making them wear a protective glove on their right hand isn't a good defense. You would want two protective gloves, a helmet and bulletproof vest.

Indeed. Trying to write code that can essentially work correctly with arbitrary memory corruption is not something that should even be attempted.

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