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author | Jerry Snitselaar <jsnitsel@redhat.com> | 2017-03-10 17:46:04 -0700 |
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committer | Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> | 2017-04-03 22:46:02 +0300 |
commit | 8569defde8057258835c51ce01a33de82e14b148 (patch) | |
tree | 6002ee224bde87f3a163f5e2656847d3731eb0c8 /drivers/char | |
parent | 4d57856a21ed2abe33412e0526cc84bdcf67ea08 (diff) | |
download | linux-stable-8569defde8057258835c51ce01a33de82e14b148.tar.gz linux-stable-8569defde8057258835c51ce01a33de82e14b148.tar.bz2 linux-stable-8569defde8057258835c51ce01a33de82e14b148.zip |
tpm_crb: check for bad response size
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.
Cc: stable@vger.kernel.org
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>
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 324561845dc2..1dfc37e33c02 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -198,8 +198,7 @@ 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); |