From 7342208d184f19a629231b57495ca7b3093ed280 Mon Sep 17 00:00:00 2001 From: "John S. Gruber" Date: Mon, 2 Sep 2019 00:00:54 +0200 Subject: [PATCH] x86/boot: Preserve boot_params.secure_boot from sanitizing commit 29d9a0b50736768f042752070e5cdf4e4d4c00df upstream. Commit a90118c445cc ("x86/boot: Save fields explicitly, zero out everything else") now zeroes the secure boot setting information (enabled/disabled/...) passed by the boot loader or by the kernel's EFI handover mechanism. The problem manifests itself with signed kernels using the EFI handoff protocol with grub and the kernel loses the information whether secure boot is enabled in the firmware, i.e., the log message "Secure boot enabled" becomes "Secure boot could not be determined". efi_main() arch/x86/boot/compressed/eboot.c sets this field early but it is subsequently zeroed by the above referenced commit. Include boot_params.secure_boot in the preserve field list. [ bp: restructure commit message and massage. ] Fixes: a90118c445cc ("x86/boot: Save fields explicitly, zero out everything else") Signed-off-by: John S. Gruber Signed-off-by: Borislav Petkov Reviewed-by: John Hubbard Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Juergen Gross Cc: Mark Brown Cc: stable Cc: Thomas Gleixner Cc: x86-ml Link: https://lkml.kernel.org/r/CAPotdmSPExAuQcy9iAHqX3js_fc4mMLQOTr5RBGvizyCOPcTQQ@mail.gmail.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/bootparam_utils.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/include/asm/bootparam_utils.h b/arch/x86/include/asm/bootparam_utils.h index d3983fdf1012..8fa49cf1211d 100644 --- a/arch/x86/include/asm/bootparam_utils.h +++ b/arch/x86/include/asm/bootparam_utils.h @@ -71,6 +71,7 @@ static void sanitize_boot_params(struct boot_params *boot_params) BOOT_PARAM_PRESERVE(eddbuf_entries), BOOT_PARAM_PRESERVE(edd_mbr_sig_buf_entries), BOOT_PARAM_PRESERVE(edd_mbr_sig_buffer), + BOOT_PARAM_PRESERVE(secure_boot), BOOT_PARAM_PRESERVE(hdr), BOOT_PARAM_PRESERVE(e820_table), BOOT_PARAM_PRESERVE(eddbuf), -- 2.20.1