Nope, it doesn't work. It compiled (after correcting one more leftover
mapping), but panicked the same way.
I've came up with a set of changes that make it working in my setup,
see attached patch. There was a problem with passing already remapped
address to tpm2_calc_event_log_size(), which tried to remap it for
second time. Few more adjustments were needed in remap-as-you-go code
so that new address is used consequently. Also, I've removed remapping
digest itself because it was never used.
I'm not certain these changes make it 100% correct, but it worked on
35 events I had in final log. Its ending seems fine now:
> [root@localhost ~]# hexdump -C /sys/kernel/security/tpm0/binary_bios_measurements | tail
> 00003720 42 6f 6f 74 20 53 65 72 76 69 63 65 73 20 49 6e |Boot Services In|
> 00003730 76 6f 63 61 74 69 6f 6e 05 00 00 00 07 00 00 80 |vocation........|
> 00003740 02 00 00 00 04 00 47 55 45 dd c9 78 d7 bf d0 36 |......GUE..x...6|
> 00003750 fa cc 7e 2e 98 7f 48 18 9f 0d 0b 00 b5 4f 75 42 |..~...H......OuB|
> 00003760 cb d8 72 a8 1a 9d 9d ea 83 9b 2b 8d 74 7c 7e bd |..r.......+.t|~.|
> 00003770 5e a6 61 5c 40 f4 2f 44 a6 db eb a0 28 00 00 00 |^.a\@./D....(...|
> 00003780 45 78 69 74 20 42 6f 6f 74 20 53 65 72 76 69 63 |Exit Boot Servic|
> 00003790 65 73 20 52 65 74 75 72 6e 65 64 20 77 69 74 68 |es Returned with|
> 000037a0 20 53 75 63 63 65 73 73 | Success|
> 000037a8
Still, some refactoring could help here as __calc_tpm2_event_size has
grown and its logic became hard to follow. IMO it's far too complex
for inline function.
Attached patch should be applied on top of jjs/master.
Bartosz
diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c
index fe48150f06d1..2c912ea08166 100644
--- a/drivers/firmware/efi/tpm.c
+++ b/drivers/firmware/efi/tpm.c
@@ -28,6 +28,7 @@ static int tpm2_calc_event_log_size(void *data, int count, void *size_info)
if (event_size == 0)
return -1;
size += event_size;
+ count--;
}
return size;
@@ -41,6 +42,7 @@ 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 ret = 0;
if (efi.tpm_log == EFI_INVALID_TABLE_ADDR) {
/*
@@ -60,10 +62,9 @@ int __init efi_tpm_eventlog_init(void)
tbl_size = sizeof(*log_tbl) + log_tbl->size;
memblock_reserve(efi.tpm_log, tbl_size);
- early_memunmap(log_tbl, sizeof(*log_tbl));
if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR)
- return 0;
+ goto out;
final_tbl = early_memremap(efi.tpm_final_log, sizeof(*final_tbl));
@@ -71,17 +72,22 @@ int __init efi_tpm_eventlog_init(void)
pr_err("Failed to map TPM Final Event Log table @ 0x%lx\n",
efi.tpm_final_log);
efi.tpm_final_log = EFI_INVALID_TABLE_ADDR;
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto out;
}
- tbl_size = tpm2_calc_event_log_size(final_tbl->events,
+ tbl_size = tpm2_calc_event_log_size(efi.tpm_final_log
+ + sizeof(final_tbl->version)
+ + sizeof(final_tbl->nr_events),
final_tbl->nr_events,
- (void *)efi.tpm_log);
+ log_tbl->log);
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;
- return 0;
+out:
+ early_memunmap(log_tbl, sizeof(*log_tbl));
+ return ret;
}
diff --git a/include/linux/tpm_eventlog.h b/include/linux/tpm_eventlog.h
index 0ca27bc053af..63238c84dc0b 100644
--- a/include/linux/tpm_eventlog.h
+++ b/include/linux/tpm_eventlog.h
@@ -185,8 +185,12 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
size = 0;
goto out;
}
+ } else {
+ mapping = marker_start;
}
+ event = (struct tcg_pcr_event2_head *)mapping;
+
efispecid = (struct tcg_efi_specid_event_head *)event_header->event;
/* Check if event is malformed. */
@@ -201,34 +205,24 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
/* Map the digest's algorithm identifier */
if (do_mapping) {
TPM_MEMUNMAP(mapping, mapping_size);
- mapping_size = marker - marker_start + halg_size;
- mapping = TPM_MEMREMAP((unsigned long)marker_start,
- mapping_size);
+ mapping_size = halg_size;
+ mapping = TPM_MEMREMAP((unsigned long)marker,
+ mapping_size);
if (!mapping) {
size = 0;
goto out;
}
+ } else {
+ mapping = marker;
}
- memcpy(&halg, marker, halg_size);
+ memcpy(&halg, mapping, 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;
-
- /* Map the digest content itself */
- if (do_mapping) {
- TPM_MEMUNMAP(mapping, mapping_size);
- mapping_size = marker - marker_start;
- mapping = TPM_MEMREMAP((unsigned long)marker_start,
- mapping_size);
- if (!mapping) {
- size = 0;
- goto out;
- }
- }
break;
}
}
@@ -239,23 +233,25 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
}
}
- event_field = (struct tcg_event_field *)marker;
-
/*
* Map the event size - we don't read from the event itself, so
* we don't need to map it
*/
if (do_mapping) {
- TPM_MEMUNMAP(marker_start, mapping_size);
+ TPM_MEMUNMAP(mapping, mapping_size);
mapping_size += sizeof(event_field->event_size);
- mapping = TPM_MEMREMAP((unsigned long)marker_start,
+ mapping = TPM_MEMREMAP((unsigned long)marker,
mapping_size);
if (!mapping) {
size = 0;
goto out;
}
+ } else {
+ mapping = marker;
}
+ event_field = (struct tcg_event_field *)mapping;
+
marker = marker + sizeof(event_field->event_size)
+ event_field->event_size;
size = marker - marker_start;
