On Thu, Jun 15, 2017 at 01:59:43PM +0200, Stephan Müller wrote: > I would think that the issue regarding the logging is relevant for > cryptographic use cases or use cases requiring strong random numbers only. > Only those use cases should be fixed eventually to wait for a fully seeded > DRNG. > > The logged messages you present here indicate use cases where no strong > security is required. It looks like that the logs show ASLR related use of > random numbers. Those do not require a fully seeded ChaCha20 DRNG.
I suspect there is a range of opinions aobut whether or not ASLR requires strongly secure random numbers or not. It seems pretty clear that if we proposed using prandom_u32 for ASLR, people would object very strongly indeed, since that would make it trivially easy for attackers to circumvent ASLR protections. > IMHO, users using the get_random_u64 or get_random_u32 are use cases that do > not require a fully seeded DRNG thus do not need a cryptographically strong > random number. Hence, I would think that the logging should be removed from > get_random_u32/u64. You are effectively proposing that there ought to be a middle range of security between prandom_32, get_random_u32/get_random_u64 and get_random_bytes(). I think that's going to lead to all sorts of complexity and bugs from people not understanding when they should use get_random_u32 vs get_random_bytes versus prandom_u32. And then we'll end up needing to audit all of the callsites for get_random_u32() so they don't violate this new usage rule that you are proposing. - Ted