iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

tpm: fix potential buffer overruns caused by bit glitches on the bus

Browse Source 
Discrete TPMs are often connected over slow serial buses which, on
some platforms, can have glitches causing bit flips.  If a bit does
flip it could cause an overrun if it's in one of the size parameters,
so sanity check that we're not overrunning the provided buffer when
doing a memcpy().

Signed-off-by: Jeremy Boone <jeremy.boone@nccgroup.trust>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
This commit is contained in:
Jeremy Boone 2018-02-08 12:28:08 -08:00 committed by James Morris
parent 6d24cd186d
commit 3be2327475
2 changed files with 8 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/char/tpm/tpm-interface.c
View File

@ -1190,6 +1190,10 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
break;
recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
if (recd > num_bytes) {
total = -EFAULT;
break;
}
rlength = be32_to_cpu(tpm_cmd.header.out.length);
if (rlength < offsetof(struct tpm_getrandom_out, rng_data) +

4
drivers/char/tpm/tpm2-cmd.c
View File

@ -683,6 +683,10 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
if (!rc) {
data_len = be16_to_cpup(
(__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE + 1) {
rc = -EFAULT;
goto out;
}
rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)
->header.out.length);