From 2bab7d273e02bb463c121233d5d7e74157844305 Mon Sep 17 00:00:00 2001 From: Hauke Mehrtens Date: Sat, 22 Apr 2023 15:28:01 +0200 Subject: [PATCH] kernel: Initialize RNG using CPU RNG and bootloader This activates the following kernel options by default: * CONFIG_RANDOM_TRUST_CPU * CONFIG_RANDOM_TRUST_BOOTLOADER With these option Linux will also use data from the CPU RNG e.g. RDRAND and the bootloader to initialize the Linux RNG if such sources are available. These random bits are used in addition to the other sources, no other sources are getting deactivated. I read that the Chacha mixer isn't vulnerable to injected entropy, so this should not be a problem even if these sources might inject bad random data. The Linux kernel suggests to activate both options, Debian also activates them. This does not increase kernel code size. Signed-off-by: Hauke Mehrtens --- target/linux/generic/config-5.10 | 4 ++-- target/linux/generic/config-5.15 | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/target/linux/generic/config-5.10 b/target/linux/generic/config-5.10 index cde0fdb0a0..3358329848 100644 --- a/target/linux/generic/config-5.10 +++ b/target/linux/generic/config-5.10 @@ -4704,8 +4704,8 @@ CONFIG_PWRSEQ_SIMPLE=y # CONFIG_RALINK is not set # CONFIG_RANDOM32_SELFTEST is not set # CONFIG_RANDOMIZE_BASE is not set -# CONFIG_RANDOM_TRUST_BOOTLOADER is not set -# CONFIG_RANDOM_TRUST_CPU is not set +CONFIG_RANDOM_TRUST_BOOTLOADER=y +CONFIG_RANDOM_TRUST_CPU=y # CONFIG_RAPIDIO is not set # CONFIG_RAS is not set # CONFIG_RAW_DRIVER is not set diff --git a/target/linux/generic/config-5.15 b/target/linux/generic/config-5.15 index 239a645231..004688c470 100644 --- a/target/linux/generic/config-5.15 +++ b/target/linux/generic/config-5.15 @@ -4946,8 +4946,8 @@ CONFIG_PWRSEQ_SIMPLE=y # CONFIG_RANDOM32_SELFTEST is not set # CONFIG_RANDOMIZE_BASE is not set # CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT is not set -# CONFIG_RANDOM_TRUST_BOOTLOADER is not set -# CONFIG_RANDOM_TRUST_CPU is not set +CONFIG_RANDOM_TRUST_BOOTLOADER=y +CONFIG_RANDOM_TRUST_CPU=y # CONFIG_RAPIDIO is not set # CONFIG_RAS is not set # CONFIG_RAW_DRIVER is not set -- 2.30.2