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A comment on The Lost Art of Structure Packing (2018). Parent comment

Re:The Lost Art of Structure Packing (2018) by rurban on Monday April 27, 2020 @05:04PM (#23000012)
Agree. memset should be secure by default. That means it should not be optimized away by the compiler. And second the secure variant should flush the content, so that cache attacks can not read secrets which were memset'ed, but still in the cache on broken CPU's (Intel).
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Re:The Lost Art of Structure Packing (2018) by saagarjha on Monday April 27, 2020 @09:45PM (#23002432)
sloooooooooooooooow. No, really, do you want a full flush every time you do a memset? That would be horrendous for performance.
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Re:The Lost Art of Structure Packing (2018) by kazinator on Tuesday April 28, 2020 @06:03PM (#23012681)
"And second the secure variant should flush ..."

Probably means the extra-secure variant, more secure than the regular non-optimized-away memset that really clears the memory, but without the flush.

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Re:The Lost Art of Structure Packing (2018) by saagarjha on Tuesday April 28, 2020 @08:19PM (#23013785)
Yeah, that's a more reasonable interpretation.
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