Commit 8569defd authored Mar 10, 2017 by Jerry Snitselaar Committed by Jarkko Sakkinen Apr 03, 2017

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: 30fc8d13 ("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>

parent 4d57856a

drivers/char/tpm/tpm_crb.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -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);