On Mon, Nov 07, 2022 at 04:35:52PM +0100, Jason A. Donenfeld wrote:
From: Ard Biesheuvel ardb@kernel.org
commit 161a438d730dade2ba2b1bf8785f0759aba4ca5f upstream.
We no longer need at least 64 bytes of random seed to permit the early crng init to complete. The RNG is now based on Blake2s, so reduce the EFI seed size to the Blake2s hash size, which is sufficient for our purposes.
While at it, drop the READ_ONCE(), which was supposed to prevent size from being evaluated after seed was unmapped. However, this cannot actually happen, so READ_ONCE() is unnecessary here. [stable: READ_ONCE() wasn't backported in the first place.]
Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Ard Biesheuvel ardb@kernel.org Reviewed-by: Jason A. Donenfeld Jason@zx2c4.com Acked-by: Ilias Apalodimas ilias.apalodimas@linaro.org Signed-off-by: Jason A. Donenfeld Jason@zx2c4.com
drivers/firmware/efi/efi.c | 2 +- include/linux/efi.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
Both backports now queued up, thanks.
greg k-h