diff mbox

[8/8] efi: Add EFI_SECURE_BOOT bit [ver #6]

Message ID 148120026820.5854.13036556358308461345.stgit@warthog.procyon.org.uk (mailing list archive)
State New, archived
Headers show

Commit Message

David Howells Dec. 8, 2016, 12:31 p.m. UTC
From: Josh Boyer <jwboyer@fedoraproject.org>

UEFI machines can be booted in Secure Boot mode.  Add a EFI_SECURE_BOOT bit
that can be passed to efi_enabled() to find out whether secure boot is
enabled.

This will be used by the SysRq+x handler, registered by the x86 arch, to find
out whether secure boot mode is enabled so that it can be disabled.

Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: David Howells <dhowells@redhat.com>
---

 arch/x86/kernel/setup.c |   15 +++++++++++++++
 include/linux/efi.h     |    1 +
 2 files changed, 16 insertions(+)


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Comments

Matt Fleming Jan. 11, 2017, 2:51 p.m. UTC | #1
On Thu, 08 Dec, at 12:31:08PM, David Howells wrote:
> From: Josh Boyer <jwboyer@fedoraproject.org>
> 
> UEFI machines can be booted in Secure Boot mode.  Add a EFI_SECURE_BOOT bit
> that can be passed to efi_enabled() to find out whether secure boot is
> enabled.
> 
> This will be used by the SysRq+x handler, registered by the x86 arch, to find
> out whether secure boot mode is enabled so that it can be disabled.
> 
> Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
> Signed-off-by: David Howells <dhowells@redhat.com>
> ---
> 
>  arch/x86/kernel/setup.c |   15 +++++++++++++++
>  include/linux/efi.h     |    1 +
>  2 files changed, 16 insertions(+)

Before we add more efi.flags bits I'd like this series to include the
patch that makes use of EFI_SECURE_BOOT. Alternatively, you move this
last patch to a new series.
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David Howells Jan. 11, 2017, 3:29 p.m. UTC | #2
Matt Fleming <matt@codeblueprint.co.uk> wrote:

> Before we add more efi.flags bits I'd like this series to include the
> patch that makes use of EFI_SECURE_BOOT. Alternatively, you move this
> last patch to a new series.

Are you willing to take the kernel lock-down patches also?

David
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Matt Fleming Jan. 16, 2017, 1:40 p.m. UTC | #3
On Wed, 11 Jan, at 03:29:24PM, David Howells wrote:
> Matt Fleming <matt@codeblueprint.co.uk> wrote:
> 
> > Before we add more efi.flags bits I'd like this series to include the
> > patch that makes use of EFI_SECURE_BOOT. Alternatively, you move this
> > last patch to a new series.
> 
> Are you willing to take the kernel lock-down patches also?

I'm happy to take them through the EFI tree provided that they've been
Reviewed/Ack-ed by the security folks.
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David Howells Jan. 16, 2017, 3:40 p.m. UTC | #4
Matt Fleming <matt@codeblueprint.co.uk> wrote:

> > > Before we add more efi.flags bits I'd like this series to include the
> > > patch that makes use of EFI_SECURE_BOOT. Alternatively, you move this
> > > last patch to a new series.
> > 
> > Are you willing to take the kernel lock-down patches also?
> 
> I'm happy to take them through the EFI tree provided that they've been
> Reviewed/Ack-ed by the security folks.

Thinking further about it, it might be best to push the EFI_SECURE_BOOT flag
into a later series and exclude that patch from this one.

David
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diff mbox

Patch

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 9c337b0e8ba7..d8972ec6257d 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1152,6 +1152,21 @@  void __init setup_arch(char **cmdline_p)
 	/* Allocate bigger log buffer */
 	setup_log_buf(1);
 
+	if (IS_ENABLED(CONFIG_EFI)) {
+		switch (boot_params.secure_boot) {
+		case efi_secureboot_mode_disabled:
+			pr_info("Secure boot disabled\n");
+			break;
+		case efi_secureboot_mode_enabled:
+			set_bit(EFI_SECURE_BOOT, &efi.flags);
+			pr_info("Secure boot enabled\n");
+			break;
+		default:
+			pr_info("Secure boot could not be determined\n");
+			break;
+		}
+	}
+
 	reserve_initrd();
 
 	acpi_table_upgrade();
diff --git a/include/linux/efi.h b/include/linux/efi.h
index c894ed5bfa1c..e1893f5002c3 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1070,6 +1070,7 @@  extern int __init efi_setup_pcdp_console(char *);
 #define EFI_ARCH_1		7	/* First arch-specific bit */
 #define EFI_DBG			8	/* Print additional debug info at runtime */
 #define EFI_NX_PE_DATA		9	/* Can runtime data regions be mapped non-executable? */
+#define EFI_SECURE_BOOT		10	/* Are we in Secure Boot mode? */
 
 #ifdef CONFIG_EFI
 /*