diff options
| author | Jerry Snitselaar <jsnitsel@redhat.com> | 2017-03-10 17:46:04 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-05-25 14:30:07 +0200 |
| commit | 63450e38efe3ce80e563827d5b3f59b3f7a12ecf (patch) | |
| tree | 2454e1ee82e1cd413cfb30aa8635c06f616c8458 /drivers/char | |
| parent | 025e33ee387a398a51588834c3172bedf4f9c485 (diff) | |
tpm_crb: check for bad response size
commit 8569defde8057258835c51ce01a33de82e14b148 upstream.
Make sure size of response buffer is at least 6 bytes, or
we will underflow and pass large size_t to memcpy_fromio().
This was encountered while testing earlier version of
locality patchset.
Fixes: 30fc8d138e912 ("tpm: TPM 2.0 CRB Interface")
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/tpm/tpm_crb.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c index 2b21398c3adc..35308dfff754 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -118,8 +118,7 @@ static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count) memcpy_fromio(buf, priv->rsp, 6); expected = be32_to_cpup((__be32 *) &buf[2]); - - if (expected > count) + if (expected > count || expected < 6) return -EIO; memcpy_fromio(&buf[6], &priv->rsp[6], expected - 6); |