Hii Ard Am 19.12.23 um 12:38 schrieb Ard Biesheuvel:
Hi Thomas, On Fri, 15 Dec 2023 at 13:26, Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:The header file <asm/efi.h> contains the macro arch_ima_efi_boot_mode, which expands to use struct boot_params from <asm/bootparams.h>. Many drivers include <linux/efi.h>, but do not use boot parameters. Changes to bootparam.h or its included headers can easily trigger large, unnessary rebuilds of the kernel. Moving x86's arch_ima_efi_boot_mode to <asm/ima-efi.h> and including <asm/setup.h> separates that dependency from the rest of the EFI interfaces. The only user is in ima_efi.c. As the file already declares a default value for arch_ima_efi_boot_mode, move this define into asm-generic for all other architectures. With arch_ima_efi_boot_mode removed from efi.h, <asm/bootparam.h> can later be removed from further x86 header files.Apologies if I missed this in v1 but is the new asm-generic header really necessary? Could we instead turn arch_ima_efi_boot_mode into a function that is a static inline { return unset; } by default, but can be emitted out of line in one of the x86/platform/efi.c source files, where referring to boot_params is fine?
I cannot figure out how to do this without *something* in asm-generic or adding if-CONFIG_X86 guards in ima-efi.c.
But I noticed that linux/efi.h already contains 2 or 3 ifdef branches for x86. Would it be an option to move this code into asm/efi.h (including a header file in asm-generic for the non-x86 variants) and add the arch_ima_efi_boot_mode() helper there as well? At least that wouldn't be a header for only a single define.
Best regards Thomas
v2: * remove extra declaration of boot_params (Ard)Please don't put the revision log here, but below the --- so that 'git am' will ignore it.Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx> --- arch/x86/include/asm/efi.h | 3 --- arch/x86/include/asm/ima-efi.h | 11 +++++++++++ include/asm-generic/Kbuild | 1 + include/asm-generic/ima-efi.h | 16 ++++++++++++++++ security/integrity/ima/ima_efi.c | 5 +---- 5 files changed, 29 insertions(+), 7 deletions(-) create mode 100644 arch/x86/include/asm/ima-efi.h create mode 100644 include/asm-generic/ima-efi.h diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index c4555b269a1b..99f31176c892 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -418,9 +418,6 @@ extern int __init efi_memmap_split_count(efi_memory_desc_t *md, extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf, struct efi_mem_range *mem); -#define arch_ima_efi_boot_mode \ - ({ extern struct boot_params boot_params; boot_params.secure_boot; }) - #ifdef CONFIG_EFI_RUNTIME_MAP int efi_get_runtime_map_size(void); int efi_get_runtime_map_desc_size(void); diff --git a/arch/x86/include/asm/ima-efi.h b/arch/x86/include/asm/ima-efi.h new file mode 100644 index 000000000000..b4d904e66b39 --- /dev/null +++ b/arch/x86/include/asm/ima-efi.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_IMA_EFI_H +#define _ASM_X86_IMA_EFI_H + +#include <asm/setup.h> + +#define arch_ima_efi_boot_mode boot_params.secure_boot + +#include <asm-generic/ima-efi.h> + +#endif /* _ASM_X86_IMA_EFI_H */ diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild index def242528b1d..4fd16e71e8cd 100644 --- a/include/asm-generic/Kbuild +++ b/include/asm-generic/Kbuild @@ -26,6 +26,7 @@ mandatory-y += ftrace.h mandatory-y += futex.h mandatory-y += hardirq.h mandatory-y += hw_irq.h +mandatory-y += ima-efi.h mandatory-y += io.h mandatory-y += irq.h mandatory-y += irq_regs.h diff --git a/include/asm-generic/ima-efi.h b/include/asm-generic/ima-efi.h new file mode 100644 index 000000000000..f87f5edef440 --- /dev/null +++ b/include/asm-generic/ima-efi.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ + +#ifndef __ASM_GENERIC_IMA_EFI_H_ +#define __ASM_GENERIC_IMA_EFI_H_ + +#include <linux/efi.h> + +/* + * Only include this header file from your architecture's <asm/ima-efi.h>. + */ + +#ifndef arch_ima_efi_boot_mode +#define arch_ima_efi_boot_mode efi_secureboot_mode_unset +#endif + +#endif /* __ASM_GENERIC_FB_H_ */ diff --git a/security/integrity/ima/ima_efi.c b/security/integrity/ima/ima_efi.c index 138029bfcce1..56bbee271cec 100644 --- a/security/integrity/ima/ima_efi.c +++ b/security/integrity/ima/ima_efi.c @@ -6,10 +6,7 @@ #include <linux/module.h> #include <linux/ima.h> #include <asm/efi.h> - -#ifndef arch_ima_efi_boot_mode -#define arch_ima_efi_boot_mode efi_secureboot_mode_unset -#endif +#include <asm/ima-efi.h> static enum efi_secureboot_mode get_sb_mode(void) { -- 2.43.0
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstrasse 146, 90461 Nuernberg, Germany GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman HRB 36809 (AG Nuernberg)
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