[v3,0/5] Use EFI variables for random seed

Message

Jason A. Donenfeld Nov. 22, 2022, 2:03 a.m. UTC

EFI has a rather unique benefit that it has access to some limited
non-volatile storage, where the kernel can store a random seed. This
series wires that up, with EFISTUB reading the seed and passing it to
the kernel, and with the kernel writing a new seed when the RNG is
initialized.

Patches 1 and 2 are to go through Ard's EFI tree, while patches 3, 4,
and 5 are to go through my RNG tree.

Jason A. Donenfeld (5):
  efi: vars: prohibit reading random seed variables
  efi: stub: use random seed from EFI variable
  random: add back async readiness notifier
  vsprintf: initialize siphash key using notifier
  efi: random: refresh non-volatile random seed when RNG is initialized

 drivers/char/random.c                 | 22 +++++++++++
 drivers/firmware/efi/efi.c            | 19 +++++++++
 drivers/firmware/efi/libstub/random.c | 55 +++++++++++++++++++++------
 fs/efivarfs/inode.c                   |  4 ++
 fs/efivarfs/super.c                   |  3 ++
 include/linux/random.h                |  1 +
 lib/vsprintf.c                        | 14 +++----
 7 files changed, 97 insertions(+), 21 deletions(-)