On Fri, Sep 23, 2022 at 2:23 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
+ if (rng_seed_record && rng_seed_record->size > sizeof(*rng_seed_record) + 2) {
+ u16 len = rng_seed_record->size - sizeof(*rng_seed_record) - 2;
+ get_random_bytes((u8 *)rng_seed_record->data + 2, len);
+ *(u16 *)rng_seed_record->data = len;
Storing the length should use the proper cpu_to_be16 accessor.
Okay, I'll do that for v2.
(Simply out of curiosity, why? Isn't m68k always big endian and this
is arch/ code?)
The way I tested this is by having my initramfs just call
`reboot(RB_AUTOBOOT);`, and having add_bootloader_randomness() print
its contents to the console. I checked that it was both present and
different every time.
Are you sure the new kernel did receive the same randomness as prepared
by get_random_bytes()? I would expect it to just reboot into qemu,
reload the kernel from disk, and recreate a new bootinfo from scratch,
including generating a new random seed.
Yes I'm sure. Without this patch, the new kernel sees the zeroed state.
Jason
