Check the size of the response before accessing data in the response packet. This is to avoid accessing data beyond the end of the response.
Signed-off-by: Stefan Berger <[email protected]> --- drivers/char/tpm/tpm-interface.c | 14 ++++++++++---- drivers/char/tpm/tpm-sysfs.c | 24 ++++++++++++++++-------- drivers/char/tpm/tpm.h | 2 +- drivers/char/tpm/tpm_tis_core.c | 3 ++- 4 files changed, 29 insertions(+), 14 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 9d6f894..f80df9c 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -470,7 +470,7 @@ static const struct tpm_input_header tpm_getcap_header = { }; ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap, - const char *desc) + const char *desc, size_t exp_rlength) { struct tpm_cmd_t tpm_cmd; int rc; @@ -495,6 +495,9 @@ ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap, } rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0, desc); + if (!rc && be32_to_cpu(tpm_cmd.header.out.length) < exp_rlength) + return -EFAULT; + if (!rc) *cap = tpm_cmd.params.getcap_out.cap; return rc; @@ -548,7 +551,8 @@ int tpm_get_timeouts(struct tpm_chip *chip) return 0; } - rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL); + rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL, + TPM_HEADER_SIZE + sizeof(cap.timeout)); if (rc == TPM_ERR_INVALID_POSTINIT) { /* The TPM is not started, we are the first to talk to it. Execute a startup command. */ @@ -557,7 +561,8 @@ int tpm_get_timeouts(struct tpm_chip *chip) return rc; rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, - "attempting to determine the timeouts"); + "attempting to determine the timeouts", + TPM_HEADER_SIZE + sizeof(cap.timeout)); } if (rc) { dev_err(&chip->dev, @@ -608,7 +613,8 @@ int tpm_get_timeouts(struct tpm_chip *chip) chip->timeout_d = usecs_to_jiffies(new_timeout[3]); rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap, - "attempting to determine the durations"); + "attempting to determine the durations", + TPM_HEAER_SIZE + sizeof(cap.duration)); if (rc) return rc; diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c index 848ad65..73d110d 100644 --- a/drivers/char/tpm/tpm-sysfs.c +++ b/drivers/char/tpm/tpm-sysfs.c @@ -95,7 +95,8 @@ static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr, struct tpm_chip *chip = to_tpm_chip(dev); rc = tpm_getcap(chip, TPM_CAP_PROP_PCR, &cap, - "attempting to determine the number of PCRS"); + "attempting to determine the number of PCRS", + TPM_HEADER_SIZE + sizeof(cap.num_pcrs)); if (rc) return 0; @@ -120,7 +121,8 @@ static ssize_t enabled_show(struct device *dev, struct device_attribute *attr, ssize_t rc; rc = tpm_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_PERM, &cap, - "attempting to determine the permanent enabled state"); + "attempting to determine the permanent enabled state", + TPM_HEADER_SIZE + sizeof(cap.perm_flags)); if (rc) return 0; @@ -136,7 +138,8 @@ static ssize_t active_show(struct device *dev, struct device_attribute *attr, ssize_t rc; rc = tpm_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_PERM, &cap, - "attempting to determine the permanent active state"); + "attempting to determine the permanent active state", + TPM_HEADER_SIZE + sizeof(cap.perm_flags)); if (rc) return 0; @@ -152,7 +155,8 @@ static ssize_t owned_show(struct device *dev, struct device_attribute *attr, ssize_t rc; rc = tpm_getcap(to_tpm_chip(dev), TPM_CAP_PROP_OWNER, &cap, - "attempting to determine the owner state"); + "attempting to determine the owner state", + TPM_HEADER_SIZE + sizeof(cap.owned)); if (rc) return 0; @@ -168,7 +172,8 @@ static ssize_t temp_deactivated_show(struct device *dev, ssize_t rc; rc = tpm_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_VOL, &cap, - "attempting to determine the temporary state"); + "attempting to determine the temporary state", + TPM_HEADER_SIZE + sizeof(cap.stclear_flags)); if (rc) return 0; @@ -186,7 +191,8 @@ static ssize_t caps_show(struct device *dev, struct device_attribute *attr, char *str = buf; rc = tpm_getcap(chip, TPM_CAP_PROP_MANUFACTURER, &cap, - "attempting to determine the manufacturer"); + "attempting to determine the manufacturer", + TPM_HEADER_SIZE + sizeof(cap.manufacturer_id)); if (rc) return 0; str += sprintf(str, "Manufacturer: 0x%x\n", @@ -194,7 +200,8 @@ static ssize_t caps_show(struct device *dev, struct device_attribute *attr, /* Try to get a TPM version 1.2 TPM_CAP_VERSION_INFO */ rc = tpm_getcap(chip, TPM_CAP_VERSION_1_2, &cap, - "attempting to determine the 1.2 version"); + "attempting to determine the 1.2 version", + TPM_HEADER_SIZE + sizeof(cap.tpm_version_1_2)); if (!rc) { str += sprintf(str, "TCG version: %d.%d\nFirmware version: %d.%d\n", @@ -205,7 +212,8 @@ static ssize_t caps_show(struct device *dev, struct device_attribute *attr, } else { /* Otherwise just use TPM_STRUCT_VER */ rc = tpm_getcap(chip, TPM_CAP_VERSION_1_1, &cap, - "attempting to determine the 1.1 version"); + "attempting to determine the 1.1 version", + TPM_HEADER_SIZE + sizeof(cap.tpm_version)); if (rc) return 0; str += sprintf(str, diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 1ae9768..8d223bb 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -496,7 +496,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz, ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *cmd, int len, unsigned int flags, const char *desc); ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap, - const char *desc); + const char *desc, size_t exp_rlength); int tpm_get_timeouts(struct tpm_chip *); int tpm1_auto_startup(struct tpm_chip *chip); int tpm_do_selftest(struct tpm_chip *chip); diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 7993678..5ce2316 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -552,7 +552,8 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip) if (chip->flags & TPM_CHIP_FLAG_TPM2) return tpm2_get_tpm_pt(chip, 0x100, &cap2, desc); else - return tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc); + return tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, + TPM_HEADER_SIZE + sizeof(cap.timeout)); } /* Register the IRQ and issue a command that will cause an interrupt. If an -- 2.4.3 ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi _______________________________________________ tpmdd-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
