Hello,
On 2024-10-14 12:26, Alex ThreeD wrote:
On Mon, Oct 14, 2024 at 12:10 AM Marek Vasut <ma...@denx.de> wrote:
Let's make this override-able via environment variable, because this
might be growing in the future again. Does this work ?
size_t len = env_get_ulong("kaslrseed_size", 10, 32);
Maybe `env_get_hex("rng_seed_size", 32)` would be better? As most other
env are
hexadecimal.
Actually it seems that entropy required to init pool early has
decreased in
Linux 5.19 from 64 bytes (2 * CHACHA_KEY_SIZE) to 32 bytes
(BLAKE2S_HASH_SIZE)
https://elixir.bootlin.com/linux/v5.18/source/drivers/char/random.c#L236
https://elixir.bootlin.com/linux/v5.19/source/drivers/char/random.c#L551
Anyway config knob should not harm.
I think that the value received from the new environment variable
should be accepted only if it's greater than some hardcoded value,
in this case 32. That way, someone won't be able to misconfigure
their board environment and cause the early random pool initialization
to be postponed.
