From 6c4e79d99e6f42b79040f1a33cd4018f5425030b Mon Sep 17 00:00:00 2001 From: Jarkko Sakkinen Date: Fri, 3 Jul 2020 01:55:59 +0300 Subject: tpm: Unify the mismatching TPM space buffer sizes The size of the buffers for storing context's and sessions can vary from arch to arch as PAGE_SIZE can be anything between 4 kB and 256 kB (the maximum for PPC64). Define a fixed buffer size set to 16 kB. This should be enough for most use with three handles (that is how many we allow at the moment). Parametrize the buffer size while doing this, so that it is easier to revisit this later on if required. Cc: stable@vger.kernel.org Reported-by: Stefan Berger Fixes: 745b361e989a ("tpm: infrastructure for TPM spaces") Reviewed-by: Jerry Snitselaar Tested-by: Stefan Berger Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm-chip.c | 9 ++------- drivers/char/tpm/tpm.h | 5 ++++- drivers/char/tpm/tpm2-space.c | 26 ++++++++++++++++---------- drivers/char/tpm/tpmrm-dev.c | 2 +- 4 files changed, 23 insertions(+), 19 deletions(-) (limited to 'drivers/char') diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 8c77e88012e9..ddaeceb7e109 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -386,13 +386,8 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev, chip->cdev.owner = THIS_MODULE; chip->cdevs.owner = THIS_MODULE; - chip->work_space.context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); - if (!chip->work_space.context_buf) { - rc = -ENOMEM; - goto out; - } - chip->work_space.session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); - if (!chip->work_space.session_buf) { + rc = tpm2_init_space(&chip->work_space, TPM2_SPACE_BUFFER_SIZE); + if (rc) { rc = -ENOMEM; goto out; } diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 0fbcede241ea..947d1db0a5cc 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -59,6 +59,9 @@ enum tpm_addr { #define TPM_TAG_RQU_COMMAND 193 +/* TPM2 specific constants. */ +#define TPM2_SPACE_BUFFER_SIZE 16384 /* 16 kB */ + struct stclear_flags_t { __be16 tag; u8 deactivated; @@ -228,7 +231,7 @@ unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal); int tpm2_probe(struct tpm_chip *chip); int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip); int tpm2_find_cc(struct tpm_chip *chip, u32 cc); -int tpm2_init_space(struct tpm_space *space); +int tpm2_init_space(struct tpm_space *space, unsigned int buf_size); void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space); void tpm2_flush_space(struct tpm_chip *chip); int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u8 *cmd, diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c index 982d341d8837..784b8b3cb903 100644 --- a/drivers/char/tpm/tpm2-space.c +++ b/drivers/char/tpm/tpm2-space.c @@ -38,18 +38,21 @@ static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space) } } -int tpm2_init_space(struct tpm_space *space) +int tpm2_init_space(struct tpm_space *space, unsigned int buf_size) { - space->context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); + space->context_buf = kzalloc(buf_size, GFP_KERNEL); if (!space->context_buf) return -ENOMEM; - space->session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); + space->session_buf = kzalloc(buf_size, GFP_KERNEL); if (space->session_buf == NULL) { kfree(space->context_buf); + /* Prevent caller getting a dangling pointer. */ + space->context_buf = NULL; return -ENOMEM; } + space->buf_size = buf_size; return 0; } @@ -311,8 +314,10 @@ int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u8 *cmd, sizeof(space->context_tbl)); memcpy(&chip->work_space.session_tbl, &space->session_tbl, sizeof(space->session_tbl)); - memcpy(chip->work_space.context_buf, space->context_buf, PAGE_SIZE); - memcpy(chip->work_space.session_buf, space->session_buf, PAGE_SIZE); + memcpy(chip->work_space.context_buf, space->context_buf, + space->buf_size); + memcpy(chip->work_space.session_buf, space->session_buf, + space->buf_size); rc = tpm2_load_space(chip); if (rc) { @@ -492,7 +497,7 @@ static int tpm2_save_space(struct tpm_chip *chip) continue; rc = tpm2_save_context(chip, space->context_tbl[i], - space->context_buf, PAGE_SIZE, + space->context_buf, space->buf_size, &offset); if (rc == -ENOENT) { space->context_tbl[i] = 0; @@ -509,9 +514,8 @@ static int tpm2_save_space(struct tpm_chip *chip) continue; rc = tpm2_save_context(chip, space->session_tbl[i], - space->session_buf, PAGE_SIZE, + space->session_buf, space->buf_size, &offset); - if (rc == -ENOENT) { /* handle error saving session, just forget it */ space->session_tbl[i] = 0; @@ -557,8 +561,10 @@ int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, sizeof(space->context_tbl)); memcpy(&space->session_tbl, &chip->work_space.session_tbl, sizeof(space->session_tbl)); - memcpy(space->context_buf, chip->work_space.context_buf, PAGE_SIZE); - memcpy(space->session_buf, chip->work_space.session_buf, PAGE_SIZE); + memcpy(space->context_buf, chip->work_space.context_buf, + space->buf_size); + memcpy(space->session_buf, chip->work_space.session_buf, + space->buf_size); return 0; out: diff --git a/drivers/char/tpm/tpmrm-dev.c b/drivers/char/tpm/tpmrm-dev.c index 7a0a7051a06f..eef0fb06ea83 100644 --- a/drivers/char/tpm/tpmrm-dev.c +++ b/drivers/char/tpm/tpmrm-dev.c @@ -21,7 +21,7 @@ static int tpmrm_open(struct inode *inode, struct file *file) if (priv == NULL) return -ENOMEM; - rc = tpm2_init_space(&priv->space); + rc = tpm2_init_space(&priv->space, TPM2_SPACE_BUFFER_SIZE); if (rc) { kfree(priv); return -ENOMEM; -- cgit v1.2.3 From 85467f63a05c43364ba0b90d0c05bb89191543fa Mon Sep 17 00:00:00 2001 From: Stefan Berger Date: Mon, 6 Jul 2020 19:58:07 -0400 Subject: tpm: Add support for event log pointer found in TPM2 ACPI table In case a TPM2 is attached, search for a TPM2 ACPI table when trying to get the event log from ACPI. If one is found, use it to get the start and length of the log area. This allows non-UEFI systems, such as SeaBIOS, to pass an event log when using a TPM2. Cc: Peter Huewe Cc: Jason Gunthorpe Signed-off-by: Stefan Berger Reviewed-by: Jerry Snitselaar Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/eventlog/acpi.c | 63 ++++++++++++++++++++++++++-------------- 1 file changed, 42 insertions(+), 21 deletions(-) (limited to 'drivers/char') diff --git a/drivers/char/tpm/eventlog/acpi.c b/drivers/char/tpm/eventlog/acpi.c index 63ada5e53f13..3633ed70f48f 100644 --- a/drivers/char/tpm/eventlog/acpi.c +++ b/drivers/char/tpm/eventlog/acpi.c @@ -49,9 +49,9 @@ int tpm_read_log_acpi(struct tpm_chip *chip) void __iomem *virt; u64 len, start; struct tpm_bios_log *log; - - if (chip->flags & TPM_CHIP_FLAG_TPM2) - return -ENODEV; + struct acpi_table_tpm2 *tbl; + struct acpi_tpm2_phy *tpm2_phy; + int format; log = &chip->log; @@ -61,23 +61,44 @@ int tpm_read_log_acpi(struct tpm_chip *chip) if (!chip->acpi_dev_handle) return -ENODEV; - /* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */ - status = acpi_get_table(ACPI_SIG_TCPA, 1, - (struct acpi_table_header **)&buff); - - if (ACPI_FAILURE(status)) - return -ENODEV; - - switch(buff->platform_class) { - case BIOS_SERVER: - len = buff->server.log_max_len; - start = buff->server.log_start_addr; - break; - case BIOS_CLIENT: - default: - len = buff->client.log_max_len; - start = buff->client.log_start_addr; - break; + if (chip->flags & TPM_CHIP_FLAG_TPM2) { + status = acpi_get_table("TPM2", 1, + (struct acpi_table_header **)&tbl); + if (ACPI_FAILURE(status)) + return -ENODEV; + + if (tbl->header.length < + sizeof(*tbl) + sizeof(struct acpi_tpm2_phy)) + return -ENODEV; + + tpm2_phy = (void *)tbl + sizeof(*tbl); + len = tpm2_phy->log_area_minimum_length; + + start = tpm2_phy->log_area_start_address; + if (!start || !len) + return -ENODEV; + + format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2; + } else { + /* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */ + status = acpi_get_table(ACPI_SIG_TCPA, 1, + (struct acpi_table_header **)&buff); + if (ACPI_FAILURE(status)) + return -ENODEV; + + switch (buff->platform_class) { + case BIOS_SERVER: + len = buff->server.log_max_len; + start = buff->server.log_start_addr; + break; + case BIOS_CLIENT: + default: + len = buff->client.log_max_len; + start = buff->client.log_start_addr; + break; + } + + format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; } if (!len) { dev_warn(&chip->dev, "%s: TCPA log area empty\n", __func__); @@ -98,7 +119,7 @@ int tpm_read_log_acpi(struct tpm_chip *chip) memcpy_fromio(log->bios_event_log, virt, len); acpi_os_unmap_iomem(virt, len); - return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; + return format; err: kfree(log->bios_event_log); -- cgit v1.2.3