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authorJosh Boyer <jwboyer@redhat.com>2013-02-18 19:54:32 -0500
committerJosh Boyer <jwboyer@redhat.com>2013-02-18 19:54:32 -0500
commitb1b2d34318ca9ef5e33a3b28a64b4003c585508a (patch)
tree975cd2488cca70a8d8179c1bb78d11cf7026384e /secure-boot-20130218.patch
parentb8330c970504e660e538fffa698c49a30fcce0ce (diff)
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Linux v3.8
- Fix build with CONFIG_EFI disabled, reported by Peter Bowey (rhbz 911833) - Disable debugging options.
Diffstat (limited to 'secure-boot-20130218.patch')
-rw-r--r--secure-boot-20130218.patch1434
1 files changed, 1434 insertions, 0 deletions
diff --git a/secure-boot-20130218.patch b/secure-boot-20130218.patch
new file mode 100644
index 000000000..29ac46cd9
--- /dev/null
+++ b/secure-boot-20130218.patch
@@ -0,0 +1,1434 @@
+From 0c5837031a4e996877930fd023a5877dd1d615ba Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg@redhat.com>
+Date: Thu, 20 Sep 2012 10:40:56 -0400
+Subject: [PATCH 01/19] Secure boot: Add new capability
+
+Secure boot adds certain policy requirements, including that root must not
+be able to do anything that could cause the kernel to execute arbitrary code.
+The simplest way to handle this would seem to be to add a new capability
+and gate various functionality on that. We'll then strip it from the initial
+capability set if required.
+
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+---
+ include/uapi/linux/capability.h | 6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+diff --git a/include/uapi/linux/capability.h b/include/uapi/linux/capability.h
+index ba478fa..7109e65 100644
+--- a/include/uapi/linux/capability.h
++++ b/include/uapi/linux/capability.h
+@@ -343,7 +343,11 @@ struct vfs_cap_data {
+
+ #define CAP_BLOCK_SUSPEND 36
+
+-#define CAP_LAST_CAP CAP_BLOCK_SUSPEND
++/* Allow things that trivially permit root to modify the running kernel */
++
++#define CAP_COMPROMISE_KERNEL 37
++
++#define CAP_LAST_CAP CAP_COMPROMISE_KERNEL
+
+ #define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)
+
+--
+1.8.1.2
+
+
+From 87c8fddbcb3042fc4174b53763adbf66045a12be Mon Sep 17 00:00:00 2001
+From: Josh Boyer <jwboyer@redhat.com>
+Date: Thu, 20 Sep 2012 10:41:05 -0400
+Subject: [PATCH 02/19] SELinux: define mapping for new Secure Boot capability
+
+Add the name of the new Secure Boot capability. This allows SELinux
+policies to properly map CAP_COMPROMISE_KERNEL to the appropriate
+capability class.
+
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ security/selinux/include/classmap.h | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
+index 14d04e6..ed99a2d 100644
+--- a/security/selinux/include/classmap.h
++++ b/security/selinux/include/classmap.h
+@@ -146,8 +146,8 @@ struct security_class_mapping secclass_map[] = {
+ { "memprotect", { "mmap_zero", NULL } },
+ { "peer", { "recv", NULL } },
+ { "capability2",
+- { "mac_override", "mac_admin", "syslog", "wake_alarm", "block_suspend",
+- NULL } },
++ { "mac_override", "mac_admin", "syslog", "wake_alarm",
++ "block_suspend", "compromise_kernel", NULL } },
+ { "kernel_service", { "use_as_override", "create_files_as", NULL } },
+ { "tun_socket",
+ { COMMON_SOCK_PERMS, "attach_queue", NULL } },
+--
+1.8.1.2
+
+
+From df14b5319bf3ed2110839e233ac61e6136745be8 Mon Sep 17 00:00:00 2001
+From: Josh Boyer <jwboyer@redhat.com>
+Date: Thu, 20 Sep 2012 10:41:02 -0400
+Subject: [PATCH 03/19] Secure boot: Add a dummy kernel parameter that will
+ switch on Secure Boot mode
+
+This forcibly drops CAP_COMPROMISE_KERNEL from both cap_permitted and cap_bset
+in the init_cred struct, which everything else inherits from. This works on
+any machine and can be used to develop even if the box doesn't have UEFI.
+
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ Documentation/kernel-parameters.txt | 7 +++++++
+ kernel/cred.c | 17 +++++++++++++++++
+ 2 files changed, 24 insertions(+)
+
+diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
+index 6c72381..7dffdd5 100644
+--- a/Documentation/kernel-parameters.txt
++++ b/Documentation/kernel-parameters.txt
+@@ -2654,6 +2654,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
+ Note: increases power consumption, thus should only be
+ enabled if running jitter sensitive (HPC/RT) workloads.
+
++ secureboot_enable=
++ [KNL] Enables an emulated UEFI Secure Boot mode. This
++ locks down various aspects of the kernel guarded by the
++ CAP_COMPROMISE_KERNEL capability. This includes things
++ like /dev/mem, IO port access, and other areas. It can
++ be used on non-UEFI machines for testing purposes.
++
+ security= [SECURITY] Choose a security module to enable at boot.
+ If this boot parameter is not specified, only the first
+ security module asking for security registration will be
+diff --git a/kernel/cred.c b/kernel/cred.c
+index e0573a4..c3f4e3e 100644
+--- a/kernel/cred.c
++++ b/kernel/cred.c
+@@ -565,6 +565,23 @@ void __init cred_init(void)
+ 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+ }
+
++void __init secureboot_enable()
++{
++ pr_info("Secure boot enabled\n");
++ cap_lower((&init_cred)->cap_bset, CAP_COMPROMISE_KERNEL);
++ cap_lower((&init_cred)->cap_permitted, CAP_COMPROMISE_KERNEL);
++}
++
++/* Dummy Secure Boot enable option to fake out UEFI SB=1 */
++static int __init secureboot_enable_opt(char *str)
++{
++ int sb_enable = !!simple_strtol(str, NULL, 0);
++ if (sb_enable)
++ secureboot_enable();
++ return 1;
++}
++__setup("secureboot_enable=", secureboot_enable_opt);
++
+ /**
+ * prepare_kernel_cred - Prepare a set of credentials for a kernel service
+ * @daemon: A userspace daemon to be used as a reference
+--
+1.8.1.2
+
+
+From 49c76a665e8a09da48cbe271ea40266ca1a226c0 Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg@redhat.com>
+Date: Thu, 20 Sep 2012 10:41:03 -0400
+Subject: [PATCH 04/19] efi: Enable secure boot lockdown automatically when
+ enabled in firmware
+
+The firmware has a set of flags that indicate whether secure boot is enabled
+and enforcing. Use them to indicate whether the kernel should lock itself
+down. We also indicate the machine is in secure boot mode by adding the
+EFI_SECURE_BOOT bit for use with efi_enabled.
+
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ Documentation/x86/zero-page.txt | 2 ++
+ arch/x86/boot/compressed/eboot.c | 32 ++++++++++++++++++++++++++++++++
+ arch/x86/include/uapi/asm/bootparam.h | 3 ++-
+ arch/x86/kernel/setup.c | 7 +++++++
+ include/linux/cred.h | 2 ++
+ include/linux/efi.h | 1 +
+ 6 files changed, 46 insertions(+), 1 deletion(-)
+
+diff --git a/Documentation/x86/zero-page.txt b/Documentation/x86/zero-page.txt
+index 199f453..ff651d3 100644
+--- a/Documentation/x86/zero-page.txt
++++ b/Documentation/x86/zero-page.txt
+@@ -30,6 +30,8 @@ Offset Proto Name Meaning
+ 1E9/001 ALL eddbuf_entries Number of entries in eddbuf (below)
+ 1EA/001 ALL edd_mbr_sig_buf_entries Number of entries in edd_mbr_sig_buffer
+ (below)
++1EB/001 ALL kbd_status Numlock is enabled
++1EC/001 ALL secure_boot Kernel should enable secure boot lockdowns
+ 1EF/001 ALL sentinel Used to detect broken bootloaders
+ 290/040 ALL edd_mbr_sig_buffer EDD MBR signatures
+ 2D0/A00 ALL e820_map E820 memory map table
+diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
+index f8fa411..96bd86b 100644
+--- a/arch/x86/boot/compressed/eboot.c
++++ b/arch/x86/boot/compressed/eboot.c
+@@ -849,6 +849,36 @@ fail:
+ return status;
+ }
+
++static int get_secure_boot(efi_system_table_t *_table)
++{
++ u8 sb, setup;
++ unsigned long datasize = sizeof(sb);
++ efi_guid_t var_guid = EFI_GLOBAL_VARIABLE_GUID;
++ efi_status_t status;
++
++ status = efi_call_phys5(sys_table->runtime->get_variable,
++ L"SecureBoot", &var_guid, NULL, &datasize, &sb);
++
++ if (status != EFI_SUCCESS)
++ return 0;
++
++ if (sb == 0)
++ return 0;
++
++
++ status = efi_call_phys5(sys_table->runtime->get_variable,
++ L"SetupMode", &var_guid, NULL, &datasize,
++ &setup);
++
++ if (status != EFI_SUCCESS)
++ return 0;
++
++ if (setup == 1)
++ return 0;
++
++ return 1;
++}
++
+ /*
+ * Because the x86 boot code expects to be passed a boot_params we
+ * need to create one ourselves (usually the bootloader would create
+@@ -1143,6 +1173,8 @@ struct boot_params *efi_main(void *handle, efi_system_table_t *_table,
+ if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
+ goto fail;
+
++ boot_params->secure_boot = get_secure_boot(sys_table);
++
+ setup_graphics(boot_params);
+
+ setup_efi_pci(boot_params);
+diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
+index c15ddaf..85d7685 100644
+--- a/arch/x86/include/uapi/asm/bootparam.h
++++ b/arch/x86/include/uapi/asm/bootparam.h
+@@ -131,7 +131,8 @@ struct boot_params {
+ __u8 eddbuf_entries; /* 0x1e9 */
+ __u8 edd_mbr_sig_buf_entries; /* 0x1ea */
+ __u8 kbd_status; /* 0x1eb */
+- __u8 _pad5[3]; /* 0x1ec */
++ __u8 secure_boot; /* 0x1ec */
++ __u8 _pad5[2]; /* 0x1ed */
+ /*
+ * The sentinel is set to a nonzero value (0xff) in header.S.
+ *
+diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
+index 8b24289..d74b441 100644
+--- a/arch/x86/kernel/setup.c
++++ b/arch/x86/kernel/setup.c
+@@ -1042,6 +1042,13 @@ void __init setup_arch(char **cmdline_p)
+
+ io_delay_init();
+
++ if (boot_params.secure_boot) {
++#ifdef CONFIG_EFI
++ set_bit(EFI_SECURE_BOOT, &x86_efi_facility);
++#endif
++ secureboot_enable();
++ }
++
+ /*
+ * Parse the ACPI tables for possible boot-time SMP configuration.
+ */
+diff --git a/include/linux/cred.h b/include/linux/cred.h
+index 04421e8..9e69542 100644
+--- a/include/linux/cred.h
++++ b/include/linux/cred.h
+@@ -156,6 +156,8 @@ extern int set_security_override_from_ctx(struct cred *, const char *);
+ extern int set_create_files_as(struct cred *, struct inode *);
+ extern void __init cred_init(void);
+
++extern void secureboot_enable(void);
++
+ /*
+ * check for validity of credentials
+ */
+diff --git a/include/linux/efi.h b/include/linux/efi.h
+index 7a9498a..1ae16b6 100644
+--- a/include/linux/efi.h
++++ b/include/linux/efi.h
+@@ -627,6 +627,7 @@ extern int __init efi_setup_pcdp_console(char *);
+ #define EFI_RUNTIME_SERVICES 3 /* Can we use runtime services? */
+ #define EFI_MEMMAP 4 /* Can we use EFI memory map? */
+ #define EFI_64BIT 5 /* Is the firmware 64-bit? */
++#define EFI_SECURE_BOOT 6 /* Are we in Secure Boot mode? */
+
+ #ifdef CONFIG_EFI
+ # ifdef CONFIG_X86
+--
+1.8.1.2
+
+
+From d4d1b3ad3e1a553c807b4ecafcbde4bf816e4db2 Mon Sep 17 00:00:00 2001
+From: Dave Howells <dhowells@redhat.com>
+Date: Tue, 23 Oct 2012 09:30:54 -0400
+Subject: [PATCH 05/19] Add EFI signature data types
+
+Add the data types that are used for containing hashes, keys and certificates
+for cryptographic verification.
+
+Signed-off-by: David Howells <dhowells@redhat.com>
+---
+ include/linux/efi.h | 20 ++++++++++++++++++++
+ 1 file changed, 20 insertions(+)
+
+diff --git a/include/linux/efi.h b/include/linux/efi.h
+index 1ae16b6..de7021d 100644
+--- a/include/linux/efi.h
++++ b/include/linux/efi.h
+@@ -388,6 +388,12 @@ typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules,
+ #define EFI_FILE_SYSTEM_GUID \
+ EFI_GUID( 0x964e5b22, 0x6459, 0x11d2, 0x8e, 0x39, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b )
+
++#define EFI_CERT_SHA256_GUID \
++ EFI_GUID( 0xc1c41626, 0x504c, 0x4092, 0xac, 0xa9, 0x41, 0xf9, 0x36, 0x93, 0x43, 0x28 )
++
++#define EFI_CERT_X509_GUID \
++ EFI_GUID( 0xa5c059a1, 0x94e4, 0x4aa7, 0x87, 0xb5, 0xab, 0x15, 0x5c, 0x2b, 0xf0, 0x72 )
++
+ typedef struct {
+ efi_guid_t guid;
+ u64 table;
+@@ -523,6 +529,20 @@ typedef struct {
+
+ #define EFI_INVALID_TABLE_ADDR (~0UL)
+
++typedef struct {
++ efi_guid_t signature_owner;
++ u8 signature_data[];
++} efi_signature_data_t;
++
++typedef struct {
++ efi_guid_t signature_type;
++ u32 signature_list_size;
++ u32 signature_header_size;
++ u32 signature_size;
++ u8 signature_header[];
++ /* efi_signature_data_t signatures[][] */
++} efi_signature_list_t;
++
+ /*
+ * All runtime access to EFI goes through this structure:
+ */
+--
+1.8.1.2
+
+
+From 3cffca89eadf7e0f0a266c370f8034f33723831a Mon Sep 17 00:00:00 2001
+From: Dave Howells <dhowells@redhat.com>
+Date: Tue, 23 Oct 2012 09:36:28 -0400
+Subject: [PATCH 06/19] Add an EFI signature blob parser and key loader.
+
+X.509 certificates are loaded into the specified keyring as asymmetric type
+keys.
+
+Signed-off-by: David Howells <dhowells@redhat.com>
+---
+ crypto/asymmetric_keys/Kconfig | 8 +++
+ crypto/asymmetric_keys/Makefile | 1 +
+ crypto/asymmetric_keys/efi_parser.c | 108 ++++++++++++++++++++++++++++++++++++
+ include/linux/efi.h | 4 ++
+ 4 files changed, 121 insertions(+)
+ create mode 100644 crypto/asymmetric_keys/efi_parser.c
+
+diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig
+index 6d2c2ea..ace9c30 100644
+--- a/crypto/asymmetric_keys/Kconfig
++++ b/crypto/asymmetric_keys/Kconfig
+@@ -35,4 +35,12 @@ config X509_CERTIFICATE_PARSER
+ data and provides the ability to instantiate a crypto key from a
+ public key packet found inside the certificate.
+
++config EFI_SIGNATURE_LIST_PARSER
++ bool "EFI signature list parser"
++ depends on EFI
++ select X509_CERTIFICATE_PARSER
++ help
++ This option provides support for parsing EFI signature lists for
++ X.509 certificates and turning them into keys.
++
+ endif # ASYMMETRIC_KEY_TYPE
+diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile
+index 0727204..cd8388e 100644
+--- a/crypto/asymmetric_keys/Makefile
++++ b/crypto/asymmetric_keys/Makefile
+@@ -8,6 +8,7 @@ asymmetric_keys-y := asymmetric_type.o signature.o
+
+ obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o
+ obj-$(CONFIG_PUBLIC_KEY_ALGO_RSA) += rsa.o
++obj-$(CONFIG_EFI_SIGNATURE_LIST_PARSER) += efi_parser.o
+
+ #
+ # X.509 Certificate handling
+diff --git a/crypto/asymmetric_keys/efi_parser.c b/crypto/asymmetric_keys/efi_parser.c
+new file mode 100644
+index 0000000..636feb1
+--- /dev/null
++++ b/crypto/asymmetric_keys/efi_parser.c
+@@ -0,0 +1,108 @@
++/* EFI signature/key/certificate list parser
++ *
++ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
++ * Written by David Howells (dhowells@redhat.com)
++ *
++ * This program is free software; you can redistribute it and/or
++ * modify it under the terms of the GNU General Public Licence
++ * as published by the Free Software Foundation; either version
++ * 2 of the Licence, or (at your option) any later version.
++ */
++
++#define pr_fmt(fmt) "EFI: "fmt
++#include <linux/module.h>
++#include <linux/printk.h>
++#include <linux/err.h>
++#include <linux/efi.h>
++#include <keys/asymmetric-type.h>
++
++static __initdata efi_guid_t efi_cert_x509_guid = EFI_CERT_X509_GUID;
++
++/**
++ * parse_efi_signature_list - Parse an EFI signature list for certificates
++ * @data: The data blob to parse
++ * @size: The size of the data blob
++ * @keyring: The keyring to add extracted keys to
++ */
++int __init parse_efi_signature_list(const void *data, size_t size, struct key *keyring)
++{
++ unsigned offs = 0;
++ size_t lsize, esize, hsize, elsize;
++
++ pr_devel("-->%s(,%zu)\n", __func__, size);
++
++ while (size > 0) {
++ efi_signature_list_t list;
++ const efi_signature_data_t *elem;
++ key_ref_t key;
++
++ if (size < sizeof(list))
++ return -EBADMSG;
++
++ memcpy(&list, data, sizeof(list));
++ pr_devel("LIST[%04x] guid=%pUl ls=%x hs=%x ss=%x\n",
++ offs,
++ list.signature_type.b, list.signature_list_size,
++ list.signature_header_size, list.signature_size);
++
++ lsize = list.signature_list_size;
++ hsize = list.signature_header_size;
++ esize = list.signature_size;
++ elsize = lsize - sizeof(list) - hsize;
++
++ if (lsize > size) {
++ pr_devel("<--%s() = -EBADMSG [overrun @%x]\n",
++ __func__, offs);
++ return -EBADMSG;
++ }
++ if (lsize < sizeof(list) ||
++ lsize - sizeof(list) < hsize ||
++ esize < sizeof(*elem) ||
++ elsize < esize ||
++ elsize % esize != 0) {
++ pr_devel("- bad size combo @%x\n", offs);
++ return -EBADMSG;
++ }
++
++ if (efi_guidcmp(list.signature_type, efi_cert_x509_guid) != 0) {
++ data += lsize;
++ size -= lsize;
++ offs += lsize;
++ continue;
++ }
++
++ data += sizeof(list) + hsize;
++ size -= sizeof(list) + hsize;
++ offs += sizeof(list) + hsize;
++
++ for (; elsize > 0; elsize -= esize) {
++ elem = data;
++
++ pr_devel("ELEM[%04x]\n", offs);
++
++ key = key_create_or_update(
++ make_key_ref(keyring, 1),
++ "asymmetric",
++ NULL,
++ &elem->signature_data,
++ esize - sizeof(*elem),
++ (KEY_POS_ALL & ~KEY_POS_SETATTR) |
++ KEY_USR_VIEW,
++ KEY_ALLOC_NOT_IN_QUOTA);
++
++ if (IS_ERR(key))
++ pr_err("Problem loading in-kernel X.509 certificate (%ld)\n",
++ PTR_ERR(key));
++ else
++ pr_notice("Loaded cert '%s' linked to '%s'\n",
++ key_ref_to_ptr(key)->description,
++ keyring->description);
++
++ data += esize;
++ size -= esize;
++ offs += esize;
++ }
++ }
++
++ return 0;
++}
+diff --git a/include/linux/efi.h b/include/linux/efi.h
+index de7021d..64b3e55 100644
+--- a/include/linux/efi.h
++++ b/include/linux/efi.h
+@@ -612,6 +612,10 @@ extern int efi_set_rtc_mmss(unsigned long nowtime);
+ extern void efi_reserve_boot_services(void);
+ extern struct efi_memory_map memmap;
+
++struct key;
++extern int __init parse_efi_signature_list(const void *data, size_t size,
++ struct key *keyring);
++
+ /**
+ * efi_range_is_wc - check the WC bit on an address range
+ * @start: starting kvirt address
+--
+1.8.1.2
+
+
+From 89ea7424726ae4f7265ab84e703cf2da77acda57 Mon Sep 17 00:00:00 2001
+From: Josh Boyer <jwboyer@redhat.com>
+Date: Fri, 26 Oct 2012 12:36:24 -0400
+Subject: [PATCH 07/19] MODSIGN: Add module certificate blacklist keyring
+
+This adds an additional keyring that is used to store certificates that
+are blacklisted. This keyring is searched first when loading signed modules
+and if the module's certificate is found, it will refuse to load. This is
+useful in cases where third party certificates are used for module signing.
+
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ init/Kconfig | 8 ++++++++
+ kernel/modsign_pubkey.c | 14 ++++++++++++++
+ kernel/module-internal.h | 3 +++
+ kernel/module_signing.c | 12 ++++++++++++
+ 4 files changed, 37 insertions(+)
+
+diff --git a/init/Kconfig b/init/Kconfig
+index be8b7f5..d972b77 100644
+--- a/init/Kconfig
++++ b/init/Kconfig
+@@ -1665,6 +1665,14 @@ config MODULE_SIG_FORCE
+ Reject unsigned modules or signed modules for which we don't have a
+ key. Without this, such modules will simply taint the kernel.
+
++config MODULE_SIG_BLACKLIST
++ bool "Support for blacklisting module signature certificates"
++ depends on MODULE_SIG
++ help
++ This adds support for keeping a blacklist of certificates that
++ should not pass module signature verification. If a module is
++ signed with something in this keyring, the load will be rejected.
++
+ choice
+ prompt "Which hash algorithm should modules be signed with?"
+ depends on MODULE_SIG
+diff --git a/kernel/modsign_pubkey.c b/kernel/modsign_pubkey.c
+index 2b6e699..4cd408d 100644
+--- a/kernel/modsign_pubkey.c
++++ b/kernel/modsign_pubkey.c
+@@ -17,6 +17,9 @@
+ #include "module-internal.h"
+
+ struct key *modsign_keyring;
++#ifdef CONFIG_MODULE_SIG_BLACKLIST
++struct key *modsign_blacklist;
++#endif
+
+ extern __initdata const u8 modsign_certificate_list[];
+ extern __initdata const u8 modsign_certificate_list_end[];
+@@ -43,6 +46,17 @@ static __init int module_verify_init(void)
+ if (IS_ERR(modsign_keyring))
+ panic("Can't allocate module signing keyring\n");
+
++#ifdef CONFIG_MODULE_SIG_BLACKLIST
++ modsign_blacklist = keyring_alloc(".modsign_blacklist",
++ KUIDT_INIT(0), KGIDT_INIT(0),
++ current_cred(),
++ (KEY_POS_ALL & ~KEY_POS_SETATTR) |
++ KEY_USR_VIEW | KEY_USR_READ,
++ KEY_ALLOC_NOT_IN_QUOTA, NULL);
++ if (IS_ERR(modsign_blacklist))
++ panic("Can't allocate module signing blacklist keyring\n");
++#endif
++
+ return 0;
+ }
+
+diff --git a/kernel/module-internal.h b/kernel/module-internal.h
+index 24f9247..51a8380 100644
+--- a/kernel/module-internal.h
++++ b/kernel/module-internal.h
+@@ -10,5 +10,8 @@
+ */
+
+ extern struct key *modsign_keyring;
++#ifdef CONFIG_MODULE_SIG_BLACKLIST
++extern struct key *modsign_blacklist;
++#endif
+
+ extern int mod_verify_sig(const void *mod, unsigned long *_modlen);
+diff --git a/kernel/module_signing.c b/kernel/module_signing.c
+index f2970bd..5423195 100644
+--- a/kernel/module_signing.c
++++ b/kernel/module_signing.c
+@@ -157,6 +157,18 @@ static struct key *request_asymmetric_key(const char *signer, size_t signer_len,
+
+ pr_debug("Look up: \"%s\"\n", id);
+
++#ifdef CONFIG_MODULE_SIG_BLACKLIST
++ key = keyring_search(make_key_ref(modsign_blacklist, 1),
++ &key_type_asymmetric, id);
++ if (!IS_ERR(key)) {
++ /* module is signed with a cert in the blacklist. reject */
++ pr_err("Module key '%s' is in blacklist\n", id);
++ key_ref_put(key);
++ kfree(id);
++ return ERR_PTR(-EKEYREJECTED);
++ }
++#endif
++
+ key = keyring_search(make_key_ref(modsign_keyring, 1),
+ &key_type_asymmetric, id);
+ if (IS_ERR(key))
+--
+1.8.1.2
+
+
+From 733a5c25b896d8d5fa0051825a671911b50cb47d Mon Sep 17 00:00:00 2001
+From: Josh Boyer <jwboyer@redhat.com>
+Date: Fri, 26 Oct 2012 12:42:16 -0400
+Subject: [PATCH 08/19] MODSIGN: Import certificates from UEFI Secure Boot
+
+Secure Boot stores a list of allowed certificates in the 'db' variable.
+This imports those certificates into the module signing keyring. This
+allows for a third party signing certificate to be used in conjunction
+with signed modules. By importing the public certificate into the 'db'
+variable, a user can allow a module signed with that certificate to
+load. The shim UEFI bootloader has a similar certificate list stored
+in the 'MokListRT' variable. We import those as well.
+
+In the opposite case, Secure Boot maintains a list of disallowed
+certificates in the 'dbx' variable. We load those certificates into
+the newly introduced module blacklist keyring and forbid any module
+signed with those from loading.
+
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ include/linux/efi.h | 6 ++++
+ init/Kconfig | 9 ++++++
+ kernel/Makefile | 3 ++
+ kernel/modsign_uefi.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++
+ 4 files changed, 108 insertions(+)
+ create mode 100644 kernel/modsign_uefi.c
+
+diff --git a/include/linux/efi.h b/include/linux/efi.h
+index 64b3e55..76fe526 100644
+--- a/include/linux/efi.h
++++ b/include/linux/efi.h
+@@ -394,6 +394,12 @@ typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules,
+ #define EFI_CERT_X509_GUID \
+ EFI_GUID( 0xa5c059a1, 0x94e4, 0x4aa7, 0x87, 0xb5, 0xab, 0x15, 0x5c, 0x2b, 0xf0, 0x72 )
+
++#define EFI_IMAGE_SECURITY_DATABASE_GUID \
++ EFI_GUID( 0xd719b2cb, 0x3d3a, 0x4596, 0xa3, 0xbc, 0xda, 0xd0, 0x0e, 0x67, 0x65, 0x6f )
++
++#define EFI_SHIM_LOCK_GUID \
++ EFI_GUID( 0x605dab50, 0xe046, 0x4300, 0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 0x8b, 0x23 )
++
+ typedef struct {
+ efi_guid_t guid;
+ u64 table;
+diff --git a/init/Kconfig b/init/Kconfig
+index d972b77..27e3a82 100644
+--- a/init/Kconfig
++++ b/init/Kconfig
+@@ -1673,6 +1673,15 @@ config MODULE_SIG_BLACKLIST
+ should not pass module signature verification. If a module is
+ signed with something in this keyring, the load will be rejected.
+
++config MODULE_SIG_UEFI
++ bool "Allow modules signed with certs stored in UEFI"
++ depends on MODULE_SIG && MODULE_SIG_BLACKLIST && EFI
++ select EFI_SIGNATURE_LIST_PARSER
++ help
++ This will import certificates stored in UEFI and allow modules
++ signed with those to be loaded. It will also disallow loading
++ of modules stored in the UEFI dbx variable.
++
+ choice
+ prompt "Which hash algorithm should modules be signed with?"
+ depends on MODULE_SIG
+diff --git a/kernel/Makefile b/kernel/Makefile
+index 6c072b6..8848829 100644
+--- a/kernel/Makefile
++++ b/kernel/Makefile
+@@ -55,6 +55,7 @@ obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
+ obj-$(CONFIG_UID16) += uid16.o
+ obj-$(CONFIG_MODULES) += module.o
+ obj-$(CONFIG_MODULE_SIG) += module_signing.o modsign_pubkey.o modsign_certificate.o
++obj-$(CONFIG_MODULE_SIG_UEFI) += modsign_uefi.o
+ obj-$(CONFIG_KALLSYMS) += kallsyms.o
+ obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
+ obj-$(CONFIG_KEXEC) += kexec.o
+@@ -114,6 +115,8 @@ obj-$(CONFIG_CONTEXT_TRACKING) += context_tracking.o
+
+ $(obj)/configs.o: $(obj)/config_data.h
+
++$(obj)/modsign_uefi.o: KBUILD_CFLAGS += -fshort-wchar
++
+ # config_data.h contains the same information as ikconfig.h but gzipped.
+ # Info from config_data can be extracted from /proc/config*
+ targets += config_data.gz
+diff --git a/kernel/modsign_uefi.c b/kernel/modsign_uefi.c
+new file mode 100644
+index 0000000..b9237d7
+--- /dev/null
++++ b/kernel/modsign_uefi.c
+@@ -0,0 +1,90 @@
++#include <linux/kernel.h>
++#include <linux/sched.h>
++#include <linux/cred.h>
++#include <linux/err.h>
++#include <linux/efi.h>
++#include <keys/asymmetric-type.h>
++#include "module-internal.h"
++
++static __init void *get_cert_list(efi_char16_t *name, efi_guid_t *guid, unsigned long *size)
++{
++ efi_status_t status;
++ unsigned long lsize = 4;
++ unsigned long tmpdb[4];
++ void *db = NULL;
++
++ status = efi.get_variable(name, guid, NULL, &lsize, &tmpdb);
++ if (status != EFI_BUFFER_TOO_SMALL) {
++ pr_err("Couldn't get size: 0x%lx\n", status);
++ return NULL;
++ }
++
++ db = kmalloc(lsize, GFP_KERNEL);
++ if (!db) {
++ pr_err("Couldn't allocate memory for uefi cert list\n");
++ goto out;
++ }
++
++ status = efi.get_variable(name, guid, NULL, &lsize, db);
++ if (status != EFI_SUCCESS) {
++ kfree(db);
++ db = NULL;
++ pr_err("Error reading db var: 0x%lx\n", status);
++ }
++out:
++ *size = lsize;
++ return db;
++}
++
++/*
++ * * Load the certs contained in the UEFI databases
++ * */
++static int __init load_uefi_certs(void)
++{
++ efi_guid_t secure_var = EFI_IMAGE_SECURITY_DATABASE_GUID;
++ efi_guid_t mok_var = EFI_SHIM_LOCK_GUID;
++ void *db = NULL, *dbx = NULL, *mok = NULL;
++ unsigned long dbsize = 0, dbxsize = 0, moksize = 0;
++ int rc = 0;
++
++ /* Check if SB is enabled and just return if not */
++ if (!efi_enabled(EFI_SECURE_BOOT))
++ return 0;
++
++ /* Get db, MokListRT, and dbx. They might not exist, so it isn't
++ * an error if we can't get them.
++ */
++ db = get_cert_list(L"db", &secure_var, &dbsize);
++ if (!db) {
++ pr_err("MODSIGN: Couldn't get UEFI db list\n");
++ } else {
++ rc = parse_efi_signature_list(db, dbsize, modsign_keyring);
++ if (rc)
++ pr_err("Couldn't parse db signatures: %d\n", rc);
++ kfree(db);
++ }
++
++ mok = get_cert_list(L"MokListRT", &mok_var, &moksize);
++ if (!mok) {
++ pr_info("MODSIGN: Couldn't get UEFI MokListRT\n");
++ } else {
++ rc = parse_efi_signature_list(mok, moksize, modsign_keyring);
++ if (rc)
++ pr_err("Couldn't parse MokListRT signatures: %d\n", rc);
++ kfree(mok);
++ }
++
++ dbx = get_cert_list(L"dbx", &secure_var, &dbxsize);
++ if (!dbx) {
++ pr_info("MODSIGN: Couldn't get UEFI dbx list\n");
++ } else {
++ rc = parse_efi_signature_list(dbx, dbxsize,
++ modsign_blacklist);
++ if (rc)
++ pr_err("Couldn't parse dbx signatures: %d\n", rc);
++ kfree(dbx);
++ }
++
++ return rc;
++}
++late_initcall(load_uefi_certs);
+--
+1.8.1.2
+
+
+From 16027d676baed34a9de804dac68d48096a688b39 Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg@redhat.com>
+Date: Thu, 20 Sep 2012 10:40:57 -0400
+Subject: [PATCH 09/19] PCI: Lock down BAR access in secure boot environments
+
+Any hardware that can potentially generate DMA has to be locked down from
+userspace in order to avoid it being possible for an attacker to cause
+arbitrary kernel behaviour. Default to paranoid - in future we can
+potentially relax this for sufficiently IOMMU-isolated devices.
+
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+---
+ drivers/pci/pci-sysfs.c | 9 +++++++++
+ drivers/pci/proc.c | 8 +++++++-
+ drivers/pci/syscall.c | 2 +-
+ 3 files changed, 17 insertions(+), 2 deletions(-)
+
+diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
+index 9c6e9bb..b966089 100644
+--- a/drivers/pci/pci-sysfs.c
++++ b/drivers/pci/pci-sysfs.c
+@@ -622,6 +622,9 @@ pci_write_config(struct file* filp, struct kobject *kobj,
+ loff_t init_off = off;
+ u8 *data = (u8*) buf;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ if (off > dev->cfg_size)
+ return 0;
+ if (off + count > dev->cfg_size) {
+@@ -928,6 +931,9 @@ pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
+ resource_size_t start, end;
+ int i;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ for (i = 0; i < PCI_ROM_RESOURCE; i++)
+ if (res == &pdev->resource[i])
+ break;
+@@ -1035,6 +1041,9 @@ pci_write_resource_io(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf,
+ loff_t off, size_t count)
+ {
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ return pci_resource_io(filp, kobj, attr, buf, off, count, true);
+ }
+
+diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c
+index 9b8505c..35580bc 100644
+--- a/drivers/pci/proc.c
++++ b/drivers/pci/proc.c
+@@ -139,6 +139,9 @@ proc_bus_pci_write(struct file *file, const char __user *buf, size_t nbytes, lof
+ int size = dp->size;
+ int cnt;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ if (pos >= size)
+ return 0;
+ if (nbytes >= size)
+@@ -219,6 +222,9 @@ static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
+ #endif /* HAVE_PCI_MMAP */
+ int ret = 0;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ switch (cmd) {
+ case PCIIOC_CONTROLLER:
+ ret = pci_domain_nr(dev->bus);
+@@ -259,7 +265,7 @@ static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
+ struct pci_filp_private *fpriv = file->private_data;
+ int i, ret;
+
+- if (!capable(CAP_SYS_RAWIO))
++ if (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL))
+ return -EPERM;
+
+ /* Make sure the caller is mapping a real resource for this device */
+diff --git a/drivers/pci/syscall.c b/drivers/pci/syscall.c
+index e1c1ec5..97e785f 100644
+--- a/drivers/pci/syscall.c
++++ b/drivers/pci/syscall.c
+@@ -92,7 +92,7 @@ SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn,
+ u32 dword;
+ int err = 0;
+
+- if (!capable(CAP_SYS_ADMIN))
++ if (!capable(CAP_SYS_ADMIN) || !capable(CAP_COMPROMISE_KERNEL))
+ return -EPERM;
+
+ dev = pci_get_bus_and_slot(bus, dfn);
+--
+1.8.1.2
+
+
+From 9ff1537bbe8c22bbf7f992027da43d4fe8da0860 Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg@redhat.com>
+Date: Thu, 20 Sep 2012 10:40:58 -0400
+Subject: [PATCH 10/19] x86: Lock down IO port access in secure boot
+ environments
+
+IO port access would permit users to gain access to PCI configuration
+registers, which in turn (on a lot of hardware) give access to MMIO register
+space. This would potentially permit root to trigger arbitrary DMA, so lock
+it down by default.
+
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+---
+ arch/x86/kernel/ioport.c | 4 ++--
+ drivers/char/mem.c | 3 +++
+ 2 files changed, 5 insertions(+), 2 deletions(-)
+
+diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c
+index 8c96897..a2578c4 100644
+--- a/arch/x86/kernel/ioport.c
++++ b/arch/x86/kernel/ioport.c
+@@ -28,7 +28,7 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on)
+
+ if ((from + num <= from) || (from + num > IO_BITMAP_BITS))
+ return -EINVAL;
+- if (turn_on && !capable(CAP_SYS_RAWIO))
++ if (turn_on && (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL)))
+ return -EPERM;
+
+ /*
+@@ -102,7 +102,7 @@ long sys_iopl(unsigned int level, struct pt_regs *regs)
+ return -EINVAL;
+ /* Trying to gain more privileges? */
+ if (level > old) {
+- if (!capable(CAP_SYS_RAWIO))
++ if (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL))
+ return -EPERM;
+ }
+ regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);
+diff --git a/drivers/char/mem.c b/drivers/char/mem.c
+index c6fa3bc..fc28099 100644
+--- a/drivers/char/mem.c
++++ b/drivers/char/mem.c
+@@ -597,6 +597,9 @@ static ssize_t write_port(struct file *file, const char __user *buf,
+ unsigned long i = *ppos;
+ const char __user * tmp = buf;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ if (!access_ok(VERIFY_READ, buf, count))
+ return -EFAULT;
+ while (count-- > 0 && i < 65536) {
+--
+1.8.1.2
+
+
+From 3b27408b1ced1ec83a3ce27f9d51161dbf7cea9a Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg@redhat.com>
+Date: Thu, 20 Sep 2012 10:40:59 -0400
+Subject: [PATCH 11/19] ACPI: Limit access to custom_method
+
+It must be impossible for even root to get code executed in kernel context
+under a secure boot environment. custom_method effectively allows arbitrary
+access to system memory, so it needs to have a capability check here.
+
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+---
+ drivers/acpi/custom_method.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/drivers/acpi/custom_method.c b/drivers/acpi/custom_method.c
+index 5d42c24..247d58b 100644
+--- a/drivers/acpi/custom_method.c
++++ b/drivers/acpi/custom_method.c
+@@ -29,6 +29,9 @@ static ssize_t cm_write(struct file *file, const char __user * user_buf,
+ struct acpi_table_header table;
+ acpi_status status;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ if (!(*ppos)) {
+ /* parse the table header to get the table length */
+ if (count <= sizeof(struct acpi_table_header))
+--
+1.8.1.2
+
+
+From fb618a04089d454b7ade68c00a2b9c7dbac013f9 Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg@redhat.com>
+Date: Thu, 20 Sep 2012 10:41:00 -0400
+Subject: [PATCH 12/19] asus-wmi: Restrict debugfs interface
+
+We have no way of validating what all of the Asus WMI methods do on a
+given machine, and there's a risk that some will allow hardware state to
+be manipulated in such a way that arbitrary code can be executed in the
+kernel. Add a capability check to prevent that.
+
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+---
+ drivers/platform/x86/asus-wmi.c | 9 +++++++++
+ 1 file changed, 9 insertions(+)
+
+diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
+index f80ae4d..059195f 100644
+--- a/drivers/platform/x86/asus-wmi.c
++++ b/drivers/platform/x86/asus-wmi.c
+@@ -1521,6 +1521,9 @@ static int show_dsts(struct seq_file *m, void *data)
+ int err;
+ u32 retval = -1;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ err = asus_wmi_get_devstate(asus, asus->debug.dev_id, &retval);
+
+ if (err < 0)
+@@ -1537,6 +1540,9 @@ static int show_devs(struct seq_file *m, void *data)
+ int err;
+ u32 retval = -1;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ err = asus_wmi_set_devstate(asus->debug.dev_id, asus->debug.ctrl_param,
+ &retval);
+
+@@ -1561,6 +1567,9 @@ static int show_call(struct seq_file *m, void *data)
+ union acpi_object *obj;
+ acpi_status status;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID,
+ 1, asus->debug.method_id,
+ &input, &output);
+--
+1.8.1.2
+
+
+From e515bbd5410d00835390fd8981aa9029e7b22b73 Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg@redhat.com>
+Date: Thu, 20 Sep 2012 10:41:01 -0400
+Subject: [PATCH 13/19] Restrict /dev/mem and /dev/kmem in secure boot setups
+
+Allowing users to write to address space makes it possible for the kernel
+to be subverted. Restrict this when we need to protect the kernel.
+
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+---
+ drivers/char/mem.c | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+diff --git a/drivers/char/mem.c b/drivers/char/mem.c
+index fc28099..b5df7a8 100644
+--- a/drivers/char/mem.c
++++ b/drivers/char/mem.c
+@@ -158,6 +158,9 @@ static ssize_t write_mem(struct file *file, const char __user *buf,
+ unsigned long copied;
+ void *ptr;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ if (!valid_phys_addr_range(p, count))
+ return -EFAULT;
+
+@@ -530,6 +533,9 @@ static ssize_t write_kmem(struct file *file, const char __user *buf,
+ char * kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
+ int err = 0;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ if (p < (unsigned long) high_memory) {
+ unsigned long to_write = min_t(unsigned long, count,
+ (unsigned long)high_memory - p);
+--
+1.8.1.2
+
+
+From fe27dd192ef250abcbaba973a14d43b21d7be497 Mon Sep 17 00:00:00 2001
+From: Josh Boyer <jwboyer@redhat.com>
+Date: Thu, 20 Sep 2012 10:41:04 -0400
+Subject: [PATCH 14/19] acpi: Ignore acpi_rsdp kernel parameter in a secure
+ boot environment
+
+This option allows userspace to pass the RSDP address to the kernel. This
+could potentially be used to circumvent the secure boot trust model.
+We ignore the setting if we don't have the CAP_COMPROMISE_KERNEL capability.
+
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ drivers/acpi/osl.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
+index bd22f86..88251d2 100644
+--- a/drivers/acpi/osl.c
++++ b/drivers/acpi/osl.c
+@@ -246,7 +246,7 @@ early_param("acpi_rsdp", setup_acpi_rsdp);
+ acpi_physical_address __init acpi_os_get_root_pointer(void)
+ {
+ #ifdef CONFIG_KEXEC
+- if (acpi_rsdp)
++ if (acpi_rsdp && capable(CAP_COMPROMISE_KERNEL))
+ return acpi_rsdp;
+ #endif
+
+--
+1.8.1.2
+
+
+From c937b2c8e179bfdadb6617c0028f558e4d701e46 Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg@redhat.com>
+Date: Tue, 4 Sep 2012 11:55:13 -0400
+Subject: [PATCH 15/19] kexec: Disable in a secure boot environment
+
+kexec could be used as a vector for a malicious user to use a signed kernel
+to circumvent the secure boot trust model. In the long run we'll want to
+support signed kexec payloads, but for the moment we should just disable
+loading entirely in that situation.
+
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+---
+ kernel/kexec.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/kernel/kexec.c b/kernel/kexec.c
+index 5e4bd78..dd464e0 100644
+--- a/kernel/kexec.c
++++ b/kernel/kexec.c
+@@ -943,7 +943,7 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
+ int result;
+
+ /* We only trust the superuser with rebooting the system. */
+- if (!capable(CAP_SYS_BOOT))
++ if (!capable(CAP_SYS_BOOT) || !capable(CAP_COMPROMISE_KERNEL))
+ return -EPERM;
+
+ /*
+--
+1.8.1.2
+
+
+From f08e390045266d53543a55afa16ca4be5a1c6316 Mon Sep 17 00:00:00 2001
+From: Josh Boyer <jwboyer@redhat.com>
+Date: Fri, 5 Oct 2012 10:12:48 -0400
+Subject: [PATCH 16/19] MODSIGN: Always enforce module signing in a Secure Boot
+ environment
+
+If a machine is booted into a Secure Boot environment, we need to
+protect the trust model. This requires that all modules be signed
+with a key that is in the kernel's _modsign keyring. The checks for
+this are already done via the 'sig_enforce' module parameter. Make
+this visible within the kernel and force it to be true.
+
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ kernel/cred.c | 8 ++++++++
+ kernel/module.c | 4 ++--
+ 2 files changed, 10 insertions(+), 2 deletions(-)
+
+diff --git a/kernel/cred.c b/kernel/cred.c
+index c3f4e3e..c5554e0 100644
+--- a/kernel/cred.c
++++ b/kernel/cred.c
+@@ -565,11 +565,19 @@ void __init cred_init(void)
+ 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+ }
+
++#ifdef CONFIG_MODULE_SIG
++extern bool sig_enforce;
++#endif
++
+ void __init secureboot_enable()
+ {
+ pr_info("Secure boot enabled\n");
+ cap_lower((&init_cred)->cap_bset, CAP_COMPROMISE_KERNEL);
+ cap_lower((&init_cred)->cap_permitted, CAP_COMPROMISE_KERNEL);
++#ifdef CONFIG_MODULE_SIG
++ /* Enable module signature enforcing */
++ sig_enforce = true;
++#endif
+ }
+
+ /* Dummy Secure Boot enable option to fake out UEFI SB=1 */
+diff --git a/kernel/module.c b/kernel/module.c
+index eab0827..93a16dc 100644
+--- a/kernel/module.c
++++ b/kernel/module.c
+@@ -109,9 +109,9 @@ struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
+
+ #ifdef CONFIG_MODULE_SIG
+ #ifdef CONFIG_MODULE_SIG_FORCE
+-static bool sig_enforce = true;
++bool sig_enforce = true;
+ #else
+-static bool sig_enforce = false;
++bool sig_enforce = false;
+
+ static int param_set_bool_enable_only(const char *val,
+ const struct kernel_param *kp)
+--
+1.8.1.2
+
+
+From 54ba1eec5847d964b1d458a240b50271b9a356a4 Mon Sep 17 00:00:00 2001
+From: Josh Boyer <jwboyer@redhat.com>
+Date: Fri, 26 Oct 2012 14:02:09 -0400
+Subject: [PATCH 17/19] hibernate: Disable in a Secure Boot environment
+
+There is currently no way to verify the resume image when returning
+from hibernate. This might compromise the secure boot trust model,
+so until we can work with signed hibernate images we disable it in
+a Secure Boot environment.
+
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ kernel/power/hibernate.c | 15 ++++++++++++++-
+ kernel/power/main.c | 7 ++++++-
+ kernel/power/user.c | 3 +++
+ 3 files changed, 23 insertions(+), 2 deletions(-)
+
+diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
+index b26f5f1..7f63cb4 100644
+--- a/kernel/power/hibernate.c
++++ b/kernel/power/hibernate.c
+@@ -28,6 +28,7 @@
+ #include <linux/syscore_ops.h>
+ #include <linux/ctype.h>
+ #include <linux/genhd.h>
++#include <linux/efi.h>
+
+ #include "power.h"
+
+@@ -632,6 +633,10 @@ int hibernate(void)
+ {
+ int error;
+
++ if (!capable(CAP_COMPROMISE_KERNEL)) {
++ return -EPERM;
++ }
++
+ lock_system_sleep();
+ /* The snapshot device should not be opened while we're running */
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+@@ -723,7 +728,7 @@ static int software_resume(void)
+ /*
+ * If the user said "noresume".. bail out early.
+ */
+- if (noresume)
++ if (noresume || !capable(CAP_COMPROMISE_KERNEL))
+ return 0;
+
+ /*
+@@ -889,6 +894,11 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
+ int i;
+ char *start = buf;
+
++ if (efi_enabled(EFI_SECURE_BOOT)) {
++ buf += sprintf(buf, "[%s]\n", "disabled");
++ return buf-start;
++ }
++
+ for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
+ if (!hibernation_modes[i])
+ continue;
+@@ -923,6 +933,9 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
+ char *p;
+ int mode = HIBERNATION_INVALID;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ p = memchr(buf, '\n', n);
+ len = p ? p - buf : n;
+
+diff --git a/kernel/power/main.c b/kernel/power/main.c
+index 1c16f91..4f915fc 100644
+--- a/kernel/power/main.c
++++ b/kernel/power/main.c
+@@ -15,6 +15,7 @@
+ #include <linux/workqueue.h>
+ #include <linux/debugfs.h>
+ #include <linux/seq_file.h>
++#include <linux/efi.h>
+
+ #include "power.h"
+
+@@ -301,7 +302,11 @@ static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
+ }
+ #endif
+ #ifdef CONFIG_HIBERNATION
+- s += sprintf(s, "%s\n", "disk");
++ if (!efi_enabled(EFI_SECURE_BOOT)) {
++ s += sprintf(s, "%s\n", "disk");
++ } else {
++ s += sprintf(s, "\n");
++ }
+ #else
+ if (s != buf)
+ /* convert the last space to a newline */
+diff --git a/kernel/power/user.c b/kernel/power/user.c
+index 4ed81e7..b11a0f4 100644
+--- a/kernel/power/user.c
++++ b/kernel/power/user.c
+@@ -48,6 +48,9 @@ static int snapshot_open(struct inode *inode, struct file *filp)
+ struct snapshot_data *data;
+ int error;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ lock_system_sleep();
+
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+--
+1.8.1.2
+
+
+From 686090054f6c3784218b318c7adcc3c1f0ca5069 Mon Sep 17 00:00:00 2001
+From: Josh Boyer <jwboyer@redhat.com>
+Date: Tue, 5 Feb 2013 19:25:05 -0500
+Subject: [PATCH 18/19] efi: Disable secure boot if shim is in insecure mode
+
+A user can manually tell the shim boot loader to disable validation of
+images it loads. When a user does this, it creates a UEFI variable called
+MokSBState that does not have the runtime attribute set. Given that the
+user explicitly disabled validation, we can honor that and not enable
+secure boot mode if that variable is set.
+
+Signed-off-by: Josh Boyer <jwboyer@redhat.com>
+---
+ arch/x86/boot/compressed/eboot.c | 20 +++++++++++++++++++-
+ 1 file changed, 19 insertions(+), 1 deletion(-)
+
+diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
+index 96bd86b..6e1331c 100644
+--- a/arch/x86/boot/compressed/eboot.c
++++ b/arch/x86/boot/compressed/eboot.c
+@@ -851,8 +851,9 @@ fail:
+
+ static int get_secure_boot(efi_system_table_t *_table)
+ {
+- u8 sb, setup;
++ u8 sb, setup, moksbstate;
+ unsigned long datasize = sizeof(sb);
++ u32 attr;
+ efi_guid_t var_guid = EFI_GLOBAL_VARIABLE_GUID;
+ efi_status_t status;
+
+@@ -876,6 +877,23 @@ static int get_secure_boot(efi_system_table_t *_table)
+ if (setup == 1)
+ return 0;
+
++ /* See if a user has put shim into insecure_mode. If so, and the variable
++ * doesn't have the runtime attribute set, we might as well honor that.
++ */
++ var_guid = EFI_SHIM_LOCK_GUID;
++ status = efi_call_phys5(sys_table->runtime->get_variable,
++ L"MokSBState", &var_guid, &attr, &datasize,
++ &moksbstate);
++
++ /* If it fails, we don't care why. Default to secure */
++ if (status != EFI_SUCCESS)
++ return 1;
++
++ if (!(attr & EFI_VARIABLE_RUNTIME_ACCESS)) {
++ if (moksbstate == 1)
++ return 0;
++ }
++
+ return 1;
+ }
+
+--
+1.8.1.2
+
+
+From df607d2d5061b04f8a686cd74edd72c1f2836d8c Mon Sep 17 00:00:00 2001
+From: Kees Cook <keescook@chromium.org>
+Date: Fri, 8 Feb 2013 11:12:13 -0800
+Subject: [PATCH 19/19] x86: Lock down MSR writing in secure boot
+
+Writing to MSRs should not be allowed unless CAP_COMPROMISE_KERNEL is
+set since it could lead to execution of arbitrary code in kernel mode.
+
+Signed-off-by: Kees Cook <keescook@chromium.org>
+---
+ arch/x86/kernel/msr.c | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c
+index 4929502..adaab3d 100644
+--- a/arch/x86/kernel/msr.c
++++ b/arch/x86/kernel/msr.c
+@@ -103,6 +103,9 @@ static ssize_t msr_write(struct file *file, const char __user *buf,
+ int err = 0;
+ ssize_t bytes = 0;
+
++ if (!capable(CAP_COMPROMISE_KERNEL))
++ return -EPERM;
++
+ if (count % 8)
+ return -EINVAL; /* Invalid chunk size */
+
+@@ -150,6 +153,10 @@ static long msr_ioctl(struct file *file, unsigned int ioc, unsigned long arg)
+ err = -EBADF;
+ break;
+ }
++ if (!capable(CAP_COMPROMISE_KERNEL)) {
++ err = -EPERM;
++ break;
++ }
+ if (copy_from_user(&regs, uregs, sizeof regs)) {
+ err = -EFAULT;
+ break;
+--
+1.8.1.2
+