From: Bartosz Szczepanek
Expect negative values from calc_tpm2_event_size as error codes.
Pass efispecid instead of event header to calc_tpm2_event_size.
Also, include tpm library in the build.
Signed-off-by: Bartosz Szczepanek
---
drivers/char/tpm/eventlog/tpm2.c | 89
include/linux/tpm_eventlog.h | 3 ++
lib/Makefile | 2 +
3 files changed, 22 insertions(+), 72 deletions(-)
diff --git a/drivers/char/tpm/eventlog/tpm2.c b/drivers/char/tpm/eventlog/tpm2.c
index 1b8fa9de2cac..5230821d5b1c 100644
--- a/drivers/char/tpm/eventlog/tpm2.c
+++ b/drivers/char/tpm/eventlog/tpm2.c
@@ -26,80 +26,20 @@
#include "../tpm.h"
#include "common.h"
-/*
- * calc_tpm2_event_size() - calculate the event size, where event
- * is an entry in the TPM 2.0 event log. The event is of type Crypto
- * Agile Log Entry Format as defined in TCG EFI Protocol Specification
- * Family "2.0".
-
- * @event: event whose size is to be calculated.
- * @event_header: the first event in the event log.
- *
- * Returns size of the event. If it is an invalid event, returns 0.
- */
-static int calc_tpm2_event_size(struct tcg_pcr_event2 *event,
- struct tcg_pcr_event *event_header)
-{
- struct tcg_efi_specid_event *efispecid;
- struct tcg_event_field *event_field;
- void *marker;
- void *marker_start;
- u32 halg_size;
- size_t size;
- u16 halg;
- int i;
- int j;
-
- marker = event;
- marker_start = marker;
- marker = marker + sizeof(event->pcr_idx) + sizeof(event->event_type)
- + sizeof(event->count);
-
- efispecid = (struct tcg_efi_specid_event *)event_header->event;
-
- /* Check if event is malformed. */
- if (event->count > efispecid->num_algs)
- return 0;
-
- for (i = 0; i < event->count; i++) {
- halg_size = sizeof(event->digests[i].alg_id);
- memcpy(, marker, halg_size);
- marker = marker + halg_size;
- for (j = 0; j < efispecid->num_algs; j++) {
- if (halg == efispecid->digest_sizes[j].alg_id) {
- marker +=
- efispecid->digest_sizes[j].digest_size;
- break;
- }
- }
- /* Algorithm without known length. Such event is unparseable. */
- if (j == efispecid->num_algs)
- return 0;
- }
-
- event_field = (struct tcg_event_field *)marker;
- marker = marker + sizeof(event_field->event_size)
- + event_field->event_size;
- size = marker - marker_start;
-
- if ((event->event_type == 0) && (event_field->event_size == 0))
- return 0;
-
- return size;
-}
-
static void *tpm2_bios_measurements_start(struct seq_file *m, loff_t *pos)
{
struct tpm_chip *chip = m->private;
struct tpm_bios_log *log = >log;
void *addr = log->bios_event_log;
void *limit = log->bios_event_log_end;
+ struct tcg_efi_specid_event *efispecid;
struct tcg_pcr_event *event_header;
struct tcg_pcr_event2 *event;
- size_t size;
+ ssize_t size;
int i;
event_header = addr;
+ efispecid = (struct tcg_efi_specid_event *) event_header->event;
size = sizeof(struct tcg_pcr_event) - sizeof(event_header->event)
+ event_header->event_size;
@@ -115,16 +55,16 @@ static void *tpm2_bios_measurements_start(struct seq_file
*m, loff_t *pos)
if (*pos > 0) {
addr += size;
event = addr;
- size = calc_tpm2_event_size(event, event_header);
- if ((addr + size >= limit) || (size == 0))
+ size = calc_tpm2_event_size(event, efispecid);
+ if ((addr + size >= limit) || (size < 0))
return NULL;
}
for (i = 0; i < (*pos - 1); i++) {
event = addr;
- size = calc_tpm2_event_size(event, event_header);
+ size = calc_tpm2_event_size(event, efispecid);
- if ((addr + size >= limit) || (size == 0))
+ if ((addr + size >= limit) || (size < 0))
return NULL;
addr += size;
}
@@ -135,6 +75,7 @@ static void *tpm2_bios_measurements_start(struct seq_file
*m, loff_t *pos)
static void *tpm2_bios_measurements_next(struct seq_file *m, void *v,
loff_t *pos)
{
+ struct tcg_efi_specid_event *efispecid;
struct tcg_pcr_event *event_header;
struct tcg_pcr_event2 *event;
struct tpm_chip *chip = m->private;
@@ -144,6 +85,7 @@ static void *tpm2_bios_measurements_next(struct seq_file *m,
void *v,
void *marker;
event_header = log->bios_event_log;
+
