Messages in this thread | | | Date | Sat, 11 Mar 2017 10:48:06 +0200 | From | Jarkko Sakkinen <> | Subject | Re: [PATCH] tpm_crb: check for bad response size |
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On Fri, Mar 10, 2017 at 05:46:04PM -0700, Jerry Snitselaar wrote: > 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>
/Jarkko
> --- > drivers/char/tpm/tpm_crb.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c > index 89dc8a176ff1..cda4f312d1c9 100644 > --- a/drivers/char/tpm/tpm_crb.c > +++ b/drivers/char/tpm/tpm_crb.c > @@ -236,7 +236,7 @@ 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); > -- > 2.11.0.258.ge05806da9 >
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