From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: [PATCH V35 07/29] Copy secure_boot flag in boot params across kexec reboot Date: Mon, 15 Jul 2019 12:59:24 -0700 Message-ID: <20190715195946.223443-8-matthewgarrett@google.com> References: <20190715195946.223443-1-matthewgarrett@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190715195946.223443-1-matthewgarrett-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+glkk-kexec=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: jmorris-gx6/JNMH7DfYtjvyW6yDsg@public.gmane.org Cc: Kees Cook , linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Matthew Garrett , David Howells , linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Dave Young List-Id: linux-api@vger.kernel.org From: Dave Young 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 Signed-off-by: Matthew Garrett Reviewed-by: Kees Cook cc: kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org --- arch/x86/kernel/kexec-bzimage64.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index 5ebcd02cbca7..d2f4e706a428 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -180,6 +180,7 @@ setup_efi_state(struct boot_params *params, unsigned long params_load_addr, 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; -- 2.22.0.510.g264f2c817a-goog