From: Dave Young Date: Wed, 8 Nov 2017 15:11:32 +0000 Subject: [07/29] Copy secure_boot flag in boot params across kexec reboot Origin: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit?id=a6b7f780bdaa731f3e2970d65dcd52fe9ba2409d Kexec reboot in case secure boot being enabled does not keep the secure boot mode in new kernel, so later one can load unsigned kernel via legacy kexec_load. In this state, the system is missing the protections provided by secure boot. Adding a patch to fix this by retain the secure_boot flag in original kernel. secure_boot flag in boot_params is set in EFI stub, but kexec bypasses the stub. Fixing this issue by copying secure_boot flag across kexec reboot. Signed-off-by: Dave Young Signed-off-by: David Howells Reviewed-by: "Lee, Chun-Yi" cc: kexec@lists.infradead.org --- arch/x86/kernel/kexec-bzimage64.c | 1 + 1 file changed, 1 insertion(+) Index: linux/arch/x86/kernel/kexec-bzimage64.c =================================================================== --- linux.orig/arch/x86/kernel/kexec-bzimage64.c +++ linux/arch/x86/kernel/kexec-bzimage64.c @@ -182,6 +182,7 @@ setup_efi_state(struct boot_params *para if (efi_enabled(EFI_OLD_MEMMAP)) return 0; + params->secure_boot = boot_params.secure_boot; ei->efi_loader_signature = current_ei->efi_loader_signature; ei->efi_systab = current_ei->efi_systab; ei->efi_systab_hi = current_ei->efi_systab_hi;