Merge tag 'efi-urgent-2020-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI fixes from Ingo Molnar:
- Fix build regression on v4.8 and older
- Robustness fix for TPM log parsing code
- kobject refcount fix for the ESRT parsing code
- Two efivarfs fixes to make it behave more like an ordinary file
system
- Style fixup for zero length arrays
- Fix a regression in path separator handling in the initrd loader
- Fix a missing prototype warning
- Add some kerneldoc headers for newly introduced stub routines
- Allow support for SSDT overrides via EFI variables to be disabled
- Report CPU mode and MMU state upon entry for 32-bit ARM
- Use the correct stack pointer alignment when entering from mixed mode
* tag 'efi-urgent-2020-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/libstub: arm: Print CPU boot mode and MMU state at boot
efi/libstub: arm: Omit arch specific config table matching array on arm64
efi/x86: Setup stack correctly for efi_pe_entry
efi: Make it possible to disable efivar_ssdt entirely
efi/libstub: Descriptions for stub helper functions
efi/libstub: Fix path separator regression
efi/libstub: Fix missing-prototype warning for skip_spaces()
efi: Replace zero-length array and use struct_size() helper
efivarfs: Don't return -EINTR when rate-limiting reads
efivarfs: Update inode modification time for successful writes
efi/esrt: Fix reference count leak in esre_create_sysfs_entry.
efi/tpm: Verify event log header before parsing
efi/x86: Fix build with gcc 4
diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h
index 84dc0ba..5dcf3c6 100644
--- a/arch/arm/include/asm/efi.h
+++ b/arch/arm/include/asm/efi.h
@@ -87,4 +87,11 @@
return dram_base + SZ_512M;
}
+struct efi_arm_entry_state {
+ u32 cpsr_before_ebs;
+ u32 sctlr_before_ebs;
+ u32 cpsr_after_ebs;
+ u32 sctlr_after_ebs;
+};
+
#endif /* _ASM_ARM_EFI_H */
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index e821a7d..97d37f0 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -213,7 +213,6 @@
* We place all of the values on our mini stack so lret can
* used to perform that far jump.
*/
- pushl $__KERNEL_CS
leal startup_64(%ebp), %eax
#ifdef CONFIG_EFI_MIXED
movl efi32_boot_args(%ebp), %edi
@@ -224,11 +223,20 @@
movl efi32_boot_args+8(%ebp), %edx // saved bootparams pointer
cmpl $0, %edx
jnz 1f
+ /*
+ * efi_pe_entry uses MS calling convention, which requires 32 bytes of
+ * shadow space on the stack even if all arguments are passed in
+ * registers. We also need an additional 8 bytes for the space that
+ * would be occupied by the return address, and this also results in
+ * the correct stack alignment for entry.
+ */
+ subl $40, %esp
leal efi_pe_entry(%ebp), %eax
movl %edi, %ecx // MS calling convention
movl %esi, %edx
1:
#endif
+ pushl $__KERNEL_CS
pushl %eax
/* Enter paged protected Mode, activating Long Mode */
@@ -784,6 +792,7 @@
SYM_DATA_START_LOCAL(boot_stack)
.fill BOOT_STACK_SIZE, 1, 0
+ .balign 16
SYM_DATA_END_LABEL(boot_stack, SYM_L_LOCAL, boot_stack_end)
/*
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index e6fc022..3939699 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -278,3 +278,14 @@
depends on SERIAL_EARLYCON && !ARM && !IA64
select FONT_SUPPORT
select ARCH_USE_MEMREMAP_PROT
+
+config EFI_CUSTOM_SSDT_OVERLAYS
+ bool "Load custom ACPI SSDT overlay from an EFI variable"
+ depends on EFI_VARS && ACPI
+ default ACPI_TABLE_UPGRADE
+ help
+ Allow loading of an ACPI SSDT overlay from an EFI variable specified
+ by a kernel command line option.
+
+ See Documentation/admin-guide/acpi/ssdt-overlays.rst for more
+ information.
diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c
index c697e70..71c445d 100644
--- a/drivers/firmware/efi/arm-init.c
+++ b/drivers/firmware/efi/arm-init.c
@@ -52,9 +52,11 @@
}
static __initdata unsigned long screen_info_table = EFI_INVALID_TABLE_ADDR;
+static __initdata unsigned long cpu_state_table = EFI_INVALID_TABLE_ADDR;
static const efi_config_table_type_t arch_tables[] __initconst = {
{LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID, &screen_info_table},
+ {LINUX_EFI_ARM_CPU_STATE_TABLE_GUID, &cpu_state_table},
{}
};
@@ -62,7 +64,8 @@
{
struct screen_info *si;
- if (screen_info_table != EFI_INVALID_TABLE_ADDR) {
+ if (IS_ENABLED(CONFIG_ARM) &&
+ screen_info_table != EFI_INVALID_TABLE_ADDR) {
si = early_memremap_ro(screen_info_table, sizeof(*si));
if (!si) {
pr_err("Could not map screen_info config table\n");
@@ -116,7 +119,8 @@
goto out;
}
retval = efi_config_parse_tables(config_tables, systab->nr_tables,
- arch_tables);
+ IS_ENABLED(CONFIG_ARM) ? arch_tables
+ : NULL);
early_memunmap(config_tables, table_size);
out:
@@ -238,9 +242,37 @@
init_screen_info();
+#ifdef CONFIG_ARM
/* ARM does not permit early mappings to persist across paging_init() */
- if (IS_ENABLED(CONFIG_ARM))
- efi_memmap_unmap();
+ efi_memmap_unmap();
+
+ if (cpu_state_table != EFI_INVALID_TABLE_ADDR) {
+ struct efi_arm_entry_state *state;
+ bool dump_state = true;
+
+ state = early_memremap_ro(cpu_state_table,
+ sizeof(struct efi_arm_entry_state));
+ if (state == NULL) {
+ pr_warn("Unable to map CPU entry state table.\n");
+ return;
+ }
+
+ if ((state->sctlr_before_ebs & 1) == 0)
+ pr_warn(FW_BUG "EFI stub was entered with MMU and Dcache disabled, please fix your firmware!\n");
+ else if ((state->sctlr_after_ebs & 1) == 0)
+ pr_warn(FW_BUG "ExitBootServices() returned with MMU and Dcache disabled, please fix your firmware!\n");
+ else
+ dump_state = false;
+
+ if (dump_state || efi_enabled(EFI_DBG)) {
+ pr_info("CPSR at EFI stub entry : 0x%08x\n", state->cpsr_before_ebs);
+ pr_info("SCTLR at EFI stub entry : 0x%08x\n", state->sctlr_before_ebs);
+ pr_info("CPSR after ExitBootServices() : 0x%08x\n", state->cpsr_after_ebs);
+ pr_info("SCTLR after ExitBootServices(): 0x%08x\n", state->sctlr_after_ebs);
+ }
+ early_memunmap(state, sizeof(struct efi_arm_entry_state));
+ }
+#endif
}
static bool efifb_overlaps_pci_range(const struct of_pci_range *range)
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 7f1657b..5114cae 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -189,7 +189,7 @@
efivars_unregister(&generic_efivars);
}
-#if IS_ENABLED(CONFIG_ACPI)
+#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
#define EFIVAR_SSDT_NAME_MAX 16
static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
static int __init efivar_ssdt_setup(char *str)
@@ -622,7 +622,8 @@
rsv = (void *)(p + prsv % PAGE_SIZE);
/* reserve the entry itself */
- memblock_reserve(prsv, EFI_MEMRESERVE_SIZE(rsv->size));
+ memblock_reserve(prsv,
+ struct_size(rsv, entry, rsv->size));
for (i = 0; i < atomic_read(&rsv->count); i++) {
memblock_reserve(rsv->entry[i].base,
diff --git a/drivers/firmware/efi/esrt.c b/drivers/firmware/efi/esrt.c
index e3d6926..d591527 100644
--- a/drivers/firmware/efi/esrt.c
+++ b/drivers/firmware/efi/esrt.c
@@ -181,7 +181,7 @@
rc = kobject_init_and_add(&entry->kobj, &esre1_ktype, NULL,
"entry%d", entry_num);
if (rc) {
- kfree(entry);
+ kobject_put(&entry->kobj);
return rc;
}
}
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 75daaf2..4cce372e 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -6,7 +6,8 @@
# enabled, even if doing so doesn't break the build.
#
cflags-$(CONFIG_X86_32) := -march=i386
-cflags-$(CONFIG_X86_64) := -mcmodel=small
+cflags-$(CONFIG_X86_64) := -mcmodel=small \
+ $(call cc-option,-maccumulate-outgoing-args)
cflags-$(CONFIG_X86) += -m$(BITS) -D__KERNEL__ \
-fPIC -fno-strict-aliasing -mno-red-zone \
-mno-mmx -mno-sse -fshort-wchar \
diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c
index 40243f5..d08e5d5 100644
--- a/drivers/firmware/efi/libstub/arm32-stub.c
+++ b/drivers/firmware/efi/libstub/arm32-stub.c
@@ -7,10 +7,49 @@
#include "efistub.h"
+static efi_guid_t cpu_state_guid = LINUX_EFI_ARM_CPU_STATE_TABLE_GUID;
+
+struct efi_arm_entry_state *efi_entry_state;
+
+static void get_cpu_state(u32 *cpsr, u32 *sctlr)
+{
+ asm("mrs %0, cpsr" : "=r"(*cpsr));
+ if ((*cpsr & MODE_MASK) == HYP_MODE)
+ asm("mrc p15, 4, %0, c1, c0, 0" : "=r"(*sctlr));
+ else
+ asm("mrc p15, 0, %0, c1, c0, 0" : "=r"(*sctlr));
+}
+
efi_status_t check_platform_features(void)
{
+ efi_status_t status;
+ u32 cpsr, sctlr;
int block;
+ get_cpu_state(&cpsr, &sctlr);
+
+ efi_info("Entering in %s mode with MMU %sabled\n",
+ ((cpsr & MODE_MASK) == HYP_MODE) ? "HYP" : "SVC",
+ (sctlr & 1) ? "en" : "dis");
+
+ status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
+ sizeof(*efi_entry_state),
+ (void **)&efi_entry_state);
+ if (status != EFI_SUCCESS) {
+ efi_err("allocate_pool() failed\n");
+ return status;
+ }
+
+ efi_entry_state->cpsr_before_ebs = cpsr;
+ efi_entry_state->sctlr_before_ebs = sctlr;
+
+ status = efi_bs_call(install_configuration_table, &cpu_state_guid,
+ efi_entry_state);
+ if (status != EFI_SUCCESS) {
+ efi_err("install_configuration_table() failed\n");
+ goto free_state;
+ }
+
/* non-LPAE kernels can run anywhere */
if (!IS_ENABLED(CONFIG_ARM_LPAE))
return EFI_SUCCESS;
@@ -19,9 +58,22 @@
block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
if (block < 5) {
efi_err("This LPAE kernel is not supported by your CPU\n");
- return EFI_UNSUPPORTED;
+ status = EFI_UNSUPPORTED;
+ goto drop_table;
}
return EFI_SUCCESS;
+
+drop_table:
+ efi_bs_call(install_configuration_table, &cpu_state_guid, NULL);
+free_state:
+ efi_bs_call(free_pool, efi_entry_state);
+ return status;
+}
+
+void efi_handle_post_ebs_state(void)
+{
+ get_cpu_state(&efi_entry_state->cpsr_after_ebs,
+ &efi_entry_state->sctlr_after_ebs);
}
static efi_guid_t screen_info_guid = LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID;
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 89f0752..d40fd68 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -32,6 +32,10 @@
return !efi_nosoftreserve;
}
+/**
+ * efi_char16_puts() - Write a UCS-2 encoded string to the console
+ * @str: UCS-2 encoded string
+ */
void efi_char16_puts(efi_char16_t *str)
{
efi_call_proto(efi_table_attr(efi_system_table, con_out),
@@ -83,6 +87,10 @@
return c32;
}
+/**
+ * efi_puts() - Write a UTF-8 encoded string to the console
+ * @str: UTF-8 encoded string
+ */
void efi_puts(const char *str)
{
efi_char16_t buf[128];
@@ -113,6 +121,16 @@
}
}
+/**
+ * efi_printk() - Print a kernel message
+ * @fmt: format string
+ *
+ * The first letter of the format string is used to determine the logging level
+ * of the message. If the level is less then the current EFI logging level, the
+ * message is suppressed. The message will be truncated to 255 bytes.
+ *
+ * Return: number of printed characters
+ */
int efi_printk(const char *fmt, ...)
{
char printf_buf[256];
@@ -154,13 +172,18 @@
return printed;
}
-/*
- * Parse the ASCII string 'cmdline' for EFI options, denoted by the efi=
+/**
+ * efi_parse_options() - Parse EFI command line options
+ * @cmdline: kernel command line
+ *
+ * Parse the ASCII string @cmdline for EFI options, denoted by the efi=
* option, e.g. efi=nochunk.
*
* It should be noted that efi= is parsed in two very different
* environments, first in the early boot environment of the EFI boot
* stub, and subsequently during the kernel boot.
+ *
+ * Return: status code
*/
efi_status_t efi_parse_options(char const *cmdline)
{
@@ -286,13 +309,21 @@
return (char *)cmdline_addr;
}
-/*
+/**
+ * efi_exit_boot_services() - Exit boot services
+ * @handle: handle of the exiting image
+ * @map: pointer to receive the memory map
+ * @priv: argument to be passed to @priv_func
+ * @priv_func: function to process the memory map before exiting boot services
+ *
* Handle calling ExitBootServices according to the requirements set out by the
* spec. Obtains the current memory map, and returns that info after calling
* ExitBootServices. The client must specify a function to perform any
* processing of the memory map data prior to ExitBootServices. A client
* specific structure may be passed to the function via priv. The client
* function may be called multiple times.
+ *
+ * Return: status code
*/
efi_status_t efi_exit_boot_services(void *handle,
struct efi_boot_memmap *map,
@@ -361,6 +392,11 @@
return status;
}
+/**
+ * get_efi_config_table() - retrieve UEFI configuration table
+ * @guid: GUID of the configuration table to be retrieved
+ * Return: pointer to the configuration table or NULL
+ */
void *get_efi_config_table(efi_guid_t guid)
{
unsigned long tables = efi_table_attr(efi_system_table, tables);
@@ -408,17 +444,18 @@
};
/**
- * efi_load_initrd_dev_path - load the initrd from the Linux initrd device path
+ * efi_load_initrd_dev_path() - load the initrd from the Linux initrd device path
* @load_addr: pointer to store the address where the initrd was loaded
* @load_size: pointer to store the size of the loaded initrd
* @max: upper limit for the initrd memory allocation
- * @return: %EFI_SUCCESS if the initrd was loaded successfully, in which
- * case @load_addr and @load_size are assigned accordingly
- * %EFI_NOT_FOUND if no LoadFile2 protocol exists on the initrd
- * device path
- * %EFI_INVALID_PARAMETER if load_addr == NULL or load_size == NULL
- * %EFI_OUT_OF_RESOURCES if memory allocation failed
- * %EFI_LOAD_ERROR in all other cases
+ *
+ * Return:
+ * * %EFI_SUCCESS if the initrd was loaded successfully, in which
+ * case @load_addr and @load_size are assigned accordingly
+ * * %EFI_NOT_FOUND if no LoadFile2 protocol exists on the initrd device path
+ * * %EFI_INVALID_PARAMETER if load_addr == NULL or load_size == NULL
+ * * %EFI_OUT_OF_RESOURCES if memory allocation failed
+ * * %EFI_LOAD_ERROR in all other cases
*/
static
efi_status_t efi_load_initrd_dev_path(unsigned long *load_addr,
@@ -481,6 +518,16 @@
load_addr, load_size);
}
+/**
+ * efi_load_initrd() - Load initial RAM disk
+ * @image: EFI loaded image protocol
+ * @load_addr: pointer to loaded initrd
+ * @load_size: size of loaded initrd
+ * @soft_limit: preferred size of allocated memory for loading the initrd
+ * @hard_limit: minimum size of allocated memory
+ *
+ * Return: status code
+ */
efi_status_t efi_load_initrd(efi_loaded_image_t *image,
unsigned long *load_addr,
unsigned long *load_size,
@@ -505,6 +552,15 @@
return status;
}
+/**
+ * efi_wait_for_key() - Wait for key stroke
+ * @usec: number of microseconds to wait for key stroke
+ * @key: key entered
+ *
+ * Wait for up to @usec microseconds for a key stroke.
+ *
+ * Return: status code, EFI_SUCCESS if key received
+ */
efi_status_t efi_wait_for_key(unsigned long usec, efi_input_key_t *key)
{
efi_event_t events[2], timer;
diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
index e97370b..3318ec3 100644
--- a/drivers/firmware/efi/libstub/efi-stub.c
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -329,6 +329,9 @@
if (status != EFI_SUCCESS)
goto fail_free_initrd;
+ if (IS_ENABLED(CONFIG_ARM))
+ efi_handle_post_ebs_state();
+
efi_enter_kernel(image_addr, fdt_addr, fdt_totalsize((void *)fdt_addr));
/* not reached */
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index bcd8c0a..2c9d422 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -157,8 +157,14 @@
#define EFI_EVT_NOTIFY_WAIT 0x00000100U
#define EFI_EVT_NOTIFY_SIGNAL 0x00000200U
-/*
- * boottime->wait_for_event takes an array of events as input.
+/**
+ * efi_set_event_at() - add event to events array
+ *
+ * @events: array of UEFI events
+ * @ids: index where to put the event in the array
+ * @event: event to add to the aray
+ *
+ * boottime->wait_for_event() takes an array of events as input.
* Provide a helper to set it up correctly for mixed mode.
*/
static inline
@@ -771,4 +777,6 @@
unsigned long soft_limit,
unsigned long hard_limit);
+void efi_handle_post_ebs_state(void);
+
#endif
diff --git a/drivers/firmware/efi/libstub/file.c b/drivers/firmware/efi/libstub/file.c
index 2005e33..630caa6 100644
--- a/drivers/firmware/efi/libstub/file.c
+++ b/drivers/firmware/efi/libstub/file.c
@@ -102,12 +102,20 @@
if (!found)
return 0;
+ /* Skip any leading slashes */
+ while (cmdline[i] == L'/' || cmdline[i] == L'\\')
+ i++;
+
while (--result_len > 0 && i < cmdline_len) {
- if (cmdline[i] == L'\0' ||
- cmdline[i] == L'\n' ||
- cmdline[i] == L' ')
+ efi_char16_t c = cmdline[i++];
+
+ if (c == L'\0' || c == L'\n' || c == L' ')
break;
- *result++ = cmdline[i++];
+ else if (c == L'/')
+ /* Replace UNIX dir separators with EFI standard ones */
+ *result++ = L'\\';
+ else
+ *result++ = c;
}
*result = L'\0';
return i;
diff --git a/drivers/firmware/efi/libstub/skip_spaces.c b/drivers/firmware/efi/libstub/skip_spaces.c
index a700b3c..159fb4e 100644
--- a/drivers/firmware/efi/libstub/skip_spaces.c
+++ b/drivers/firmware/efi/libstub/skip_spaces.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/ctype.h>
+#include <linux/string.h>
#include <linux/types.h>
char *skip_spaces(const char *str)
diff --git a/fs/efivarfs/file.c b/fs/efivarfs/file.c
index e9e27a2..feaa5e1 100644
--- a/fs/efivarfs/file.c
+++ b/fs/efivarfs/file.c
@@ -51,6 +51,7 @@
} else {
inode_lock(inode);
i_size_write(inode, datasize + sizeof(attributes));
+ inode->i_mtime = current_time(inode);
inode_unlock(inode);
}
@@ -72,10 +73,8 @@
ssize_t size = 0;
int err;
- while (!__ratelimit(&file->f_cred->user->ratelimit)) {
- if (!msleep_interruptible(50))
- return -EINTR;
- }
+ while (!__ratelimit(&file->f_cred->user->ratelimit))
+ msleep(50);
err = efivar_entry_size(var, &datasize);
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 2c6495f..bb35f33 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -350,6 +350,7 @@
* associated with ConOut
*/
#define LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID EFI_GUID(0xe03fc20a, 0x85dc, 0x406e, 0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95)
+#define LINUX_EFI_ARM_CPU_STATE_TABLE_GUID EFI_GUID(0xef79e4aa, 0x3c3d, 0x4989, 0xb9, 0x02, 0x07, 0xa9, 0x43, 0xe5, 0x50, 0xd2)
#define LINUX_EFI_LOADER_ENTRY_GUID EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf, 0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f)
#define LINUX_EFI_RANDOM_SEED_TABLE_GUID EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2, 0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b)
#define LINUX_EFI_TPM_EVENT_LOG_GUID EFI_GUID(0xb7799cb0, 0xeca2, 0x4943, 0x96, 0x67, 0x1f, 0xae, 0x07, 0xb7, 0x47, 0xfa)
@@ -1236,14 +1237,11 @@
struct {
phys_addr_t base;
phys_addr_t size;
- } entry[0];
+ } entry[];
};
-#define EFI_MEMRESERVE_SIZE(count) (sizeof(struct linux_efi_memreserve) + \
- (count) * sizeof(((struct linux_efi_memreserve *)0)->entry[0]))
-
#define EFI_MEMRESERVE_COUNT(size) (((size) - sizeof(struct linux_efi_memreserve)) \
- / sizeof(((struct linux_efi_memreserve *)0)->entry[0]))
+ / sizeof_field(struct linux_efi_memreserve, entry[0]))
void __init efi_arch_mem_reserve(phys_addr_t addr, u64 size);
diff --git a/include/linux/tpm_eventlog.h b/include/linux/tpm_eventlog.h
index 4f8c90c..64356b1 100644
--- a/include/linux/tpm_eventlog.h
+++ b/include/linux/tpm_eventlog.h
@@ -81,6 +81,8 @@
u16 digest_size;
} __packed;
+#define TCG_SPECID_SIG "Spec ID Event03"
+
struct tcg_efi_specid_event_head {
u8 signature[16];
u32 platform_class;
@@ -171,6 +173,7 @@
int i;
int j;
u32 count, event_type;
+ const u8 zero_digest[sizeof(event_header->digest)] = {0};
marker = event;
marker_start = marker;
@@ -198,10 +201,19 @@
count = READ_ONCE(event->count);
event_type = READ_ONCE(event->event_type);
+ /* Verify that it's the log header */
+ if (event_header->pcr_idx != 0 ||
+ event_header->event_type != NO_ACTION ||
+ memcmp(event_header->digest, zero_digest, sizeof(zero_digest))) {
+ size = 0;
+ goto out;
+ }
+
efispecid = (struct tcg_efi_specid_event_head *)event_header->event;
/* Check if event is malformed. */
- if (count > efispecid->num_algs) {
+ if (memcmp(efispecid->signature, TCG_SPECID_SIG,
+ sizeof(TCG_SPECID_SIG)) || count > efispecid->num_algs) {
size = 0;
goto out;
}
