Add a flag to detect Apple T2 chips on Intel Macs. Cache the result to avoid repeated checks. That will be used in upcoming patches.
Signed-off-by: Atharva Tiwari <[email protected]> --- arch/x86/kernel/quirks.c | 105 ++++++++++++++++++ include/linux/platform_data/x86/apple.h | 5 + security/integrity/platform_certs/load_uefi.c | 38 ++----- 3 files changed, 118 insertions(+), 30 deletions(-) diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c index a92f18db9610..74b29738d404 100644 --- a/arch/x86/kernel/quirks.c +++ b/arch/x86/kernel/quirks.c @@ -664,8 +664,113 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2083, quirk_intel_purley_xeon_ras bool x86_apple_machine; EXPORT_SYMBOL(x86_apple_machine); +bool has_apple_t2_chip; +EXPORT_SYMBOL(has_apple_t2_chip); + +static const struct dmi_system_id apple_t2_devices[] = { + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,1"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,2"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,3"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,4"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,1"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,2"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,3"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,4"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir8,1"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir8,2"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir9,1"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Macmini8,1"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "MacPro7,1"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "iMac20,1"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "iMac20,2"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "iMacPro1,1"), + }, + }, + { } +}; + void __init early_platform_quirks(void) { x86_apple_machine = dmi_match(DMI_SYS_VENDOR, "Apple Inc.") || dmi_match(DMI_SYS_VENDOR, "Apple Computer, Inc."); + + has_apple_t2_chip = dmi_check_system(apple_t2_devices); } diff --git a/include/linux/platform_data/x86/apple.h b/include/linux/platform_data/x86/apple.h index 079e816c3c21..50bbcc5134fc 100644 --- a/include/linux/platform_data/x86/apple.h +++ b/include/linux/platform_data/x86/apple.h @@ -6,8 +6,13 @@ * x86_apple_machine - whether the machine is an x86 Apple Macintosh */ extern bool x86_apple_machine; +/** + * has_apple_t2_chip - whether the machine has the Apple T2 chip + */ +extern bool has_apple_t2_chip; #else #define x86_apple_machine false +#define has_t2_chip false #endif #endif diff --git a/security/integrity/platform_certs/load_uefi.c b/security/integrity/platform_certs/load_uefi.c index c0d6948446c3..b4096d4c828d 100644 --- a/security/integrity/platform_certs/load_uefi.c +++ b/security/integrity/platform_certs/load_uefi.c @@ -3,42 +3,16 @@ #include <linux/kernel.h> #include <linux/sched.h> #include <linux/cred.h> -#include <linux/dmi.h> #include <linux/err.h> #include <linux/efi.h> #include <linux/slab.h> #include <linux/ima.h> +#include <linux/platform_data/x86/apple.h> #include <keys/asymmetric-type.h> #include <keys/system_keyring.h> #include "../integrity.h" #include "keyring_handler.h" -/* - * On T2 Macs reading the db and dbx efi variables to load UEFI Secure Boot - * certificates causes occurrence of a page fault in Apple's firmware and - * a crash disabling EFI runtime services. The following quirk skips reading - * these variables. - */ -static const struct dmi_system_id uefi_skip_cert[] = { - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro15,1") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro15,2") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro15,3") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro15,4") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro16,1") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro16,2") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro16,3") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro16,4") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookAir8,1") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookAir8,2") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookAir9,1") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "Macmini8,1") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacPro7,1") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "iMac20,1") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "iMac20,2") }, - { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "iMacPro1,1") }, - { } -}; - /* * Look to see if a UEFI variable called MokIgnoreDB exists and return true if * it does. @@ -165,10 +139,14 @@ static int __init load_uefi_certs(void) unsigned long dbsize = 0, dbxsize = 0, mokxsize = 0; efi_status_t status; int rc = 0; - const struct dmi_system_id *dmi_id; - dmi_id = dmi_first_match(uefi_skip_cert); - if (dmi_id) { + /* + * On T2 Macs reading the db and dbx efi variables to load UEFI Secure Boot + * certificates causes occurrence of a page fault in Apple's firmware and + * a crash disabling EFI runtime services. The following quirk skips reading + * these variables. + */ + if (has_apple_t2_chip) { pr_err("Reading UEFI Secure Boot Certs is not supported on T2 Macs.\n"); return false; } -- 2.43.0
