• Jason A. Donenfeld's avatar
    random: do not re-init if crng_reseed completes before primary init · 9c3ddde3
    Jason A. Donenfeld authored
    If the bootloader supplies sufficient material and crng_reseed() is called
    very early on, but not too early that wqs aren't available yet, then we
    might transition to crng_init==2 before rand_initialize()'s call to
    crng_initialize_primary() made. Then, when crng_initialize_primary() is
    called, if we're trusting the CPU's RDRAND instructions, we'll
    needlessly reinitialize the RNG and emit a message about it. This is
    mostly harmless, as numa_crng_init() will allocate and then free what it
    just allocated, and excessive calls to invalidate_batched_entropy()
    aren't so harmful. But it is funky and the extra message is confusing,
    so avoid the re-initialization all together by checking for crng_init <
    2 in crng_initialize_primary(), just as we already do in crng_reseed().
    Reviewed-by: default avatarDominik Brodowski <linux@dominikbrodowski.net>
    Signed-off-by: default avatarJason A. Donenfeld <Jason@zx2c4.com>
    9c3ddde3
random.c 68.2 KB