From 506bf0c0464ace57169aadcf02ae397999c57bdd Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Wed, 18 Mar 2015 00:17:00 -0700 Subject: [PATCH] hwrng: core - allow perfect entropy from hardware devices Hardware random number quality is measured from 0 (no entropy) to 1024 (perfect entropy). Allow hardware devices to assert the full range by truncating the device-provided value at 1024 instead of 1023. Signed-off-by: Keith Packard Signed-off-by: Herbert Xu --- drivers/char/hw_random/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 83161dde53ee..571ef61f8ea9 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -179,7 +179,8 @@ skip_init: add_early_randomness(rng); current_quality = rng->quality ? : default_quality; - current_quality &= 1023; + if (current_quality > 1024) + current_quality = 1024; if (current_quality == 0 && hwrng_fill) kthread_stop(hwrng_fill); -- 2.20.1