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-rw-r--r--drivers/char/tpm/eventlog/acpi.c33
-rw-r--r--drivers/char/tpm/eventlog/common.c3
-rw-r--r--drivers/char/tpm/eventlog/efi.c29
3 files changed, 56 insertions, 9 deletions
diff --git a/drivers/char/tpm/eventlog/acpi.c b/drivers/char/tpm/eventlog/acpi.c
index 3633ed70f48f..1b18ce5ebab1 100644
--- a/drivers/char/tpm/eventlog/acpi.c
+++ b/drivers/char/tpm/eventlog/acpi.c
@@ -41,6 +41,27 @@ struct acpi_tcpa {
};
};
+/* Check that the given log is indeed a TPM2 log. */
+static bool tpm_is_tpm2_log(void *bios_event_log, u64 len)
+{
+ struct tcg_efi_specid_event_head *efispecid;
+ struct tcg_pcr_event *event_header;
+ int n;
+
+ if (len < sizeof(*event_header))
+ return false;
+ len -= sizeof(*event_header);
+ event_header = bios_event_log;
+
+ if (len < sizeof(*efispecid))
+ return false;
+ efispecid = (struct tcg_efi_specid_event_head *)event_header->event;
+
+ n = memcmp(efispecid->signature, TCG_SPECID_SIG,
+ sizeof(TCG_SPECID_SIG));
+ return n == 0;
+}
+
/* read binary bios log */
int tpm_read_log_acpi(struct tpm_chip *chip)
{
@@ -52,6 +73,7 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
struct acpi_table_tpm2 *tbl;
struct acpi_tpm2_phy *tpm2_phy;
int format;
+ int ret;
log = &chip->log;
@@ -112,6 +134,7 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
log->bios_event_log_end = log->bios_event_log + len;
+ ret = -EIO;
virt = acpi_os_map_iomem(start, len);
if (!virt)
goto err;
@@ -119,11 +142,19 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
memcpy_fromio(log->bios_event_log, virt, len);
acpi_os_unmap_iomem(virt, len);
+
+ if (chip->flags & TPM_CHIP_FLAG_TPM2 &&
+ !tpm_is_tpm2_log(log->bios_event_log, len)) {
+ /* try EFI log next */
+ ret = -ENODEV;
+ goto err;
+ }
+
return format;
err:
kfree(log->bios_event_log);
log->bios_event_log = NULL;
- return -EIO;
+ return ret;
}
diff --git a/drivers/char/tpm/eventlog/common.c b/drivers/char/tpm/eventlog/common.c
index 7460f230bae4..8512ec76d526 100644
--- a/drivers/char/tpm/eventlog/common.c
+++ b/drivers/char/tpm/eventlog/common.c
@@ -107,6 +107,9 @@ void tpm_bios_log_setup(struct tpm_chip *chip)
int log_version;
int rc = 0;
+ if (chip->flags & TPM_CHIP_FLAG_VIRTUAL)
+ return;
+
rc = tpm_read_log(chip);
if (rc < 0)
return;
diff --git a/drivers/char/tpm/eventlog/efi.c b/drivers/char/tpm/eventlog/efi.c
index 35229e5143ca..e6cb9d525e30 100644
--- a/drivers/char/tpm/eventlog/efi.c
+++ b/drivers/char/tpm/eventlog/efi.c
@@ -17,6 +17,7 @@ int tpm_read_log_efi(struct tpm_chip *chip)
{
struct efi_tcg2_final_events_table *final_tbl = NULL;
+ int final_events_log_size = efi_tpm_final_log_size;
struct linux_efi_tpm_eventlog *log_tbl;
struct tpm_bios_log *log;
u32 log_size;
@@ -66,12 +67,12 @@ int tpm_read_log_efi(struct tpm_chip *chip)
ret = tpm_log_version;
if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR ||
- efi_tpm_final_log_size == 0 ||
+ final_events_log_size == 0 ||
tpm_log_version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2)
goto out;
final_tbl = memremap(efi.tpm_final_log,
- sizeof(*final_tbl) + efi_tpm_final_log_size,
+ sizeof(*final_tbl) + final_events_log_size,
MEMREMAP_WB);
if (!final_tbl) {
pr_err("Could not map UEFI TPM final log\n");
@@ -80,10 +81,18 @@ int tpm_read_log_efi(struct tpm_chip *chip)
goto out;
}
- efi_tpm_final_log_size -= log_tbl->final_events_preboot_size;
+ /*
+ * The 'final events log' size excludes the 'final events preboot log'
+ * at its beginning.
+ */
+ final_events_log_size -= log_tbl->final_events_preboot_size;
+ /*
+ * Allocate memory for the 'combined log' where we will append the
+ * 'final events log' to.
+ */
tmp = krealloc(log->bios_event_log,
- log_size + efi_tpm_final_log_size,
+ log_size + final_events_log_size,
GFP_KERNEL);
if (!tmp) {
kfree(log->bios_event_log);
@@ -94,15 +103,19 @@ int tpm_read_log_efi(struct tpm_chip *chip)
log->bios_event_log = tmp;
/*
- * Copy any of the final events log that didn't also end up in the
- * main log. Events can be logged in both if events are generated
+ * Append any of the 'final events log' that didn't also end up in the
+ * 'main log'. Events can be logged in both if events are generated
* between GetEventLog() and ExitBootServices().
*/
memcpy((void *)log->bios_event_log + log_size,
final_tbl->events + log_tbl->final_events_preboot_size,
- efi_tpm_final_log_size);
+ final_events_log_size);
+ /*
+ * The size of the 'combined log' is the size of the 'main log' plus
+ * the size of the 'final events log'.
+ */
log->bios_event_log_end = log->bios_event_log +
- log_size + efi_tpm_final_log_size;
+ log_size + final_events_log_size;
out:
memunmap(final_tbl);