From: Bartosz Szczepanek <bsz@xxxxxxxxxxxx> 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 <bsz@xxxxxxxxxxxx> --- 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(&halg, 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 = &chip->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; + efispecid = (struct tcg_efi_specid_event *) event_header->event; if (v == SEQ_START_TOKEN) { event_size = sizeof(struct tcg_pcr_event) - @@ -151,8 +93,8 @@ static void *tpm2_bios_measurements_next(struct seq_file *m, void *v, marker = event_header; } else { event = v; - event_size = calc_tpm2_event_size(event, event_header); - if (event_size == 0) + event_size = calc_tpm2_event_size(event, efispecid); + if (event_size < 0) return NULL; marker = event; } @@ -163,8 +105,8 @@ static void *tpm2_bios_measurements_next(struct seq_file *m, void *v, v = marker; event = v; - event_size = calc_tpm2_event_size(event, event_header); - if (((v + event_size) >= limit) || (event_size == 0)) + event_size = calc_tpm2_event_size(event, efispecid); + if (((v + event_size) >= limit) || (event_size < 0)) return NULL; (*pos)++; @@ -180,10 +122,13 @@ static int tpm2_binary_bios_measurements_show(struct seq_file *m, void *v) struct tpm_chip *chip = m->private; struct tpm_bios_log *log = &chip->log; struct tcg_pcr_event *event_header = log->bios_event_log; + struct tcg_efi_specid_event *efispecid; struct tcg_pcr_event2 *event = v; void *temp_ptr; size_t size; + efispecid = (struct tcg_efi_specid_event *) event_header->event; + if (v == SEQ_START_TOKEN) { size = sizeof(struct tcg_pcr_event) - sizeof(event_header->event) + event_header->event_size; @@ -193,7 +138,7 @@ static int tpm2_binary_bios_measurements_show(struct seq_file *m, void *v) if (size > 0) seq_write(m, temp_ptr, size); } else { - size = calc_tpm2_event_size(event, event_header); + size = calc_tpm2_event_size(event, efispecid); temp_ptr = event; if (size > 0) seq_write(m, temp_ptr, size); diff --git a/include/linux/tpm_eventlog.h b/include/linux/tpm_eventlog.h index 20d9da77fc11..872ab1545456 100644 --- a/include/linux/tpm_eventlog.h +++ b/include/linux/tpm_eventlog.h @@ -121,4 +121,7 @@ struct tcg_pcr_event2 { struct tcg_event_field event; } __packed; +ssize_t calc_tpm2_event_size(struct tcg_pcr_event2 *event, + struct tcg_efi_specid_event *efispecid); + #endif diff --git a/lib/Makefile b/lib/Makefile index e1b59da71418..4458d914f40b 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -276,3 +276,5 @@ obj-$(CONFIG_GENERIC_LIB_MULDI3) += muldi3.o obj-$(CONFIG_GENERIC_LIB_CMPDI2) += cmpdi2.o obj-$(CONFIG_GENERIC_LIB_UCMPDI2) += ucmpdi2.o obj-$(CONFIG_OBJAGG) += objagg.o + +obj-$(CONFIG_TCG_TPM) += tpm.o -- 2.14.4