Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull EFI fixes from Ingo Molnar:
 "Misc EFI fixes all across the map: CPER error report fixes, fixes to
  TPM event log parsing, fix for a kexec hang, a Sparse fix and other
  fixes"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/tpm: Fix sanity check of unsigned tbl_size being less than zero
  efi/x86: Do not clean dummy variable in kexec path
  efi: Make unexported efi_rci2_sysfs_init() static
  efi/tpm: Only set 'efi_tpm_final_log_size' after successful event log parsing
  efi/tpm: Don't traverse an event log with no events
  efi/tpm: Don't access event->count when it isn't mapped
  efivar/ssdt: Don't iterate over EFI vars if no SSDT override was specified
  efi/cper: Fix endianness of PCIe class code

arch/x86/platform/efi/efi.c

@@ -917,9 +917,6 @@ static void __init kexec_enter_virtual_mode(void)
 
 	if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX))
 		runtime_code_page_mkexec();
-
-	/* clean DUMMY object */
-	efi_delete_dummy_variable();
 #endif
 }
 

drivers/firmware/efi/cper.c

@@ -381,7 +381,7 @@ static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie,
 		printk("%s""vendor_id: 0x%04x, device_id: 0x%04x\n", pfx,
 		       pcie->device_id.vendor_id, pcie->device_id.device_id);
 		p = pcie->device_id.class_code;
-		printk("%s""class_code: %02x%02x%02x\n", pfx, p[0], p[1], p[2]);
+		printk("%s""class_code: %02x%02x%02x\n", pfx, p[2], p[1], p[0]);
 	}
 	if (pcie->validation_bits & CPER_PCIE_VALID_SERIAL_NUMBER)
 		printk("%s""serial number: 0x%04x, 0x%04x\n", pfx,

drivers/firmware/efi/efi.c

@@ -267,6 +267,9 @@ static __init int efivar_ssdt_load(void)
 	void *data;
 	int ret;
 
+	if (!efivar_ssdt[0])
+		return 0;
+
 	ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
 
 	list_for_each_entry_safe(entry, aux, &entries, list) {

drivers/firmware/efi/rci2-table.c

@@ -76,7 +76,7 @@ static u16 checksum(void)
 	return chksum;
 }
 
-int __init efi_rci2_sysfs_init(void)
+static int __init efi_rci2_sysfs_init(void)
 {
 	struct kobject *tables_kobj;
 	int ret = -ENOMEM;

drivers/firmware/efi/tpm.c

@@ -40,7 +40,7 @@ int __init efi_tpm_eventlog_init(void)
 {
 	struct linux_efi_tpm_eventlog *log_tbl;
 	struct efi_tcg2_final_events_table *final_tbl;
-	unsigned int tbl_size;
+	int tbl_size;
 	int ret = 0;
 
 	if (efi.tpm_log == EFI_INVALID_TABLE_ADDR) {
@@ -75,16 +75,28 @@ int __init efi_tpm_eventlog_init(void)
 		goto out;
 	}
 
-	tbl_size = tpm2_calc_event_log_size((void *)efi.tpm_final_log
-					    + sizeof(final_tbl->version)
-					    + sizeof(final_tbl->nr_events),
-					    final_tbl->nr_events,
-					    log_tbl->log);
+	tbl_size = 0;
+	if (final_tbl->nr_events != 0) {
+		void *events = (void *)efi.tpm_final_log
+				+ sizeof(final_tbl->version)
+				+ sizeof(final_tbl->nr_events);
+
+		tbl_size = tpm2_calc_event_log_size(events,
+						    final_tbl->nr_events,
+						    log_tbl->log);
+	}
+
+	if (tbl_size < 0) {
+		pr_err(FW_BUG "Failed to parse event in TPM Final Events Log\n");
+		goto out_calc;
+	}
+
 	memblock_reserve((unsigned long)final_tbl,
 			 tbl_size + sizeof(*final_tbl));
-	early_memunmap(final_tbl, sizeof(*final_tbl));
 	efi_tpm_final_log_size = tbl_size;
 
+out_calc:
+	early_memunmap(final_tbl, sizeof(*final_tbl));
 out:
 	early_memunmap(log_tbl, sizeof(*log_tbl));
 	return ret;

include/linux/tpm_eventlog.h

@@ -152,7 +152,7 @@ struct tcg_algorithm_info {
  * total. Once we've done this we know the offset of the data length field,
  * and can calculate the total size of the event.
  *
- * Return: size of the event on success, <0 on failure
+ * Return: size of the event on success, 0 on failure
  */
 
 static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
@@ -170,6 +170,7 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
 	u16 halg;
 	int i;
 	int j;
+	u32 count, event_type;
 
 	marker = event;
 	marker_start = marker;
@@ -190,16 +191,22 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
 	}
 
 	event = (struct tcg_pcr_event2_head *)mapping;
+	/*
+	 * The loop below will unmap these fields if the log is larger than
+	 * one page, so save them here for reference:
+	 */
+	count = READ_ONCE(event->count);
+	event_type = READ_ONCE(event->event_type);
 
 	efispecid = (struct tcg_efi_specid_event_head *)event_header->event;
 
 	/* Check if event is malformed. */
-	if (event->count > efispecid->num_algs) {
+	if (count > efispecid->num_algs) {
 		size = 0;
 		goto out;
 	}
 
-	for (i = 0; i < event->count; i++) {
+	for (i = 0; i < count; i++) {
 		halg_size = sizeof(event->digests[i].alg_id);
 
 		/* Map the digest's algorithm identifier */
@@ -256,8 +263,9 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
 		+ event_field->event_size;
 	size = marker - marker_start;
 
-	if ((event->event_type == 0) && (event_field->event_size == 0))
+	if (event_type == 0 && event_field->event_size == 0)
 		size = 0;
+
 out:
 	if (do_mapping)
 		TPM_MEMUNMAP(mapping, mapping_size);