Hacker News new | ask | show | jobs
by LtWorf 395 days ago
Current kernels zero pages. The code was buggy to begin with.
1 comments

No, there was no bug. The code used an uninitialised array as a place to XOR randomness from various sources into. It didn't initialise the array since there was no value in doing so, because the whole point is to be random anyway.
As I said, new kernels zero the pages, an uninitialized area is likely to be zeroed or be rather deterministic.
Which is fine. It's not a bug if it's zero. There's just no point going out of your way to set it to zero when you're only going to xor a bunch of random values into it anyway.
The whole issue was caused because it was always zero because the patch zeroed it (:

Can you please read about the issue before commenting more?

> The whole issue was caused because it was always zero because the patch zeroed it (:

No it wasn't. The patch removed the read of the randomness buffer that folded it into another buffer (the MD_Update calls) because Valgrind was warning that the buffer it was reading from had never been initialised.

> Can you please read about the issue before commenting more?

Right back at you.