diff options
| author |   Stefan Mahnke-Hartmann <stefan.mahnke-hartmann@infineon.com> | 2022-05-13 15:41:51 +0200 |
|---|---|---|
| committer |   Jarkko Sakkinen <jarkko@kernel.org> | 2022-05-23 18:47:49 +0300 |
| commit | e57b2523bd37e6434f4e64c7a685e3715ad21e9a (patch) | |
| tree | bdf69a62db205486f29407390b3ccf984655bf35 /drivers/char/tpm/tpm2-cmd.c | |
| parent | char: tpm: cr50_i2c: Suppress duplicated error message in .remove() (diff) | |
| download | linux-dev-e57b2523bd37e6434f4e64c7a685e3715ad21e9a.tar.xz linux-dev-e57b2523bd37e6434f4e64c7a685e3715ad21e9a.zip | |
tpm: Fix buffer access in tpm2_get_tpm_pt()
Under certain conditions uninitialized memory will be accessed.
As described by TCG Trusted Platform Module Library Specification,
rev. 1.59 (Part 3: Commands), if a TPM2_GetCapability is received,
requesting a capability, the TPM in field upgrade mode may return a
zero length list.
Check the property count in tpm2_get_tpm_pt().
Fixes: 2ab3241161b3 ("tpm: migrate tpm2_get_tpm_pt() to use struct tpm_buf")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Mahnke-Hartmann <stefan.mahnke-hartmann@infineon.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Diffstat (limited to 'drivers/char/tpm/tpm2-cmd.c')
| -rw-r--r-- | drivers/char/tpm/tpm2-cmd.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 4704fa553098..04a3e23a4afc 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -400,7 +400,16 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value, if (!rc) { out = (struct tpm2_get_cap_out *) &buf.data[TPM_HEADER_SIZE]; - *value = be32_to_cpu(out->value); + /* + * To prevent failing boot up of some systems, Infineon TPM2.0 + * returns SUCCESS on TPM2_Startup in field upgrade mode. Also + * the TPM2_Getcapability command returns a zero length list + * in field upgrade mode. + */ + if (be32_to_cpu(out->property_cnt) > 0) + *value = be32_to_cpu(out->value); + else + rc = -ENODATA; } tpm_buf_destroy(&buf); return rc; |