Andrew Ayer

Anonymous on 2014-07-15 at 14:55:

The rationale for not aborting is there: unsafe core files. Is it worse than sketchy entropy? I can't tell. It's a case by case thing really. Also, the sketchy looking code isn't necessarily all that bad. Keep this in mind people, rdrand is a rather recent addition and prior to that, most common systems weren't expected to have a hardware random generator. So we devised lots of ways to collect entropy from timing and supposedly unpredictable events. The in-kernel entropy generation has always seemed sketchy, just like the fallback function. Ugly it is, but not necessarily bad. Also, some of the kernel entropy is likely to be in the data the fallback uses; see AT_RANDOM, ASLR, PIE, etc. Hopefully though Linux will get a getentropy() call and we can get rid of the sketchy looking code. I think everyone should be happy with that.

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