[PATCH 2/3] random: rng-seed source is utf-8

Masami Hiramatsu
2020-02-14T06:10:36Z

From: Mark Salyzyn <salyzyn@android.com>

commit 428826f5358c922dc378830a1717b682c0823160
("fdt: add support for rng-seed") makes the assumption that the data
in rng-seed is binary, when it is typically constructed of utf-8
characters which has a bitness of roughly 6 to give appropriate
credit due for the entropy.

Fixes: 428826f5358c ("fdt: add support for rng-seed")
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Cc: linux-kernel@vger.kernel.org
Cc: kernel-team@android.com
Cc: Kees Cook <keescook@chromium.org>
Cc: Theodore Y. Ts'o <tytso@mit.edu>
---
drivers/char/random.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index c7f9584de2c8..ee21a6a584b1 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -2306,7 +2306,7 @@ EXPORT_SYMBOL_GPL(add_hwgenerator_randomness);
void add_bootloader_randomness(const void *buf, unsigned int size)
{
if (IS_ENABLED(CONFIG_RANDOM_TRUST_BOOTLOADER))
- add_hwgenerator_randomness(buf, size, size * 8);
+ add_hwgenerator_randomness(buf, size, size * 6);
else
add_device_randomness(buf, size);
}