* [PATCH] tpm_crb: check for bad response size
@ 2017-03-11 0:46 Jerry Snitselaar
2017-03-11 8:48 ` Jarkko Sakkinen
0 siblings, 1 reply; 2+ messages in thread
From: Jerry Snitselaar @ 2017-03-11 0:46 UTC (permalink / raw)
To: tpmdd-devel
Cc: linux-kernel, Jarkko Sakkinen, Jason Gunthorpe, Jerry Snitselaar
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>
---
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
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH] tpm_crb: check for bad response size
2017-03-11 0:46 [PATCH] tpm_crb: check for bad response size Jerry Snitselaar
@ 2017-03-11 8:48 ` Jarkko Sakkinen
0 siblings, 0 replies; 2+ messages in thread
From: Jarkko Sakkinen @ 2017-03-11 8:48 UTC (permalink / raw)
To: Jerry Snitselaar; +Cc: tpmdd-devel, linux-kernel, Jason Gunthorpe
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
>
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2017-03-11 8:48 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-03-11 0:46 [PATCH] tpm_crb: check for bad response size Jerry Snitselaar
2017-03-11 8:48 ` Jarkko Sakkinen
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox