diff options
Diffstat (limited to 'secure-boot-20130218.patch')
| -rw-r--r-- | secure-boot-20130218.patch | 1434 |
1 files changed, 0 insertions, 1434 deletions
diff --git a/secure-boot-20130218.patch b/secure-boot-20130218.patch deleted file mode 100644 index 29ac46cd9..000000000 --- a/secure-boot-20130218.patch +++ /dev/null @@ -1,1434 +0,0 @@ -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(®s, uregs, sizeof regs)) { - err = -EFAULT; - break; --- -1.8.1.2 - |