Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1234732 > unrolled thread

[PATCH] tpm, tpm_crb: fix unaligned read of the command buffer address

Back to article view | Back to linux.kernel

Contents

  [PATCH] tpm, tpm_crb: fix unaligned read of the command buffer address Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2015-09-29 08:10 +0200
    Re: [PATCH] tpm, tpm_crb: fix unaligned read of the command buffer address Peter Huewe <peterhuewe@gmx.de> - 2015-09-29 08:20 +0200
      Re: [PATCH] tpm, tpm_crb: fix unaligned read of the command buffer  address Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2015-09-29 09:20 +0200

#1234732 — [PATCH] tpm, tpm_crb: fix unaligned read of the command buffer address

The command buffer address must be read with exactly two 32-bit reads.
Otherwise, on Broxton platform HW will abort the read operation, which
causes the CPU to fill the read with 1's. Therefore, we cannot rely on
memcpy_fromio() but must call ioread32() two times instead.

Also, this matches the PC Client Platform TPM Profile specification,
which defines command buffer address with two 32-bit fields.

Reported-by: Imran Desai <imran.desai@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
 drivers/char/tpm/tpm_crb.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index b4564b6..c09b370 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -68,7 +68,8 @@ struct crb_control_area {
 	u32 int_enable;
 	u32 int_sts;
 	u32 cmd_size;
-	u64 cmd_pa;
+	u32 cmd_pa_low;
+	u32 cmd_pa_high;
 	u32 rsp_size;
 	u64 rsp_pa;
 } __packed;
@@ -263,8 +264,8 @@ static int crb_acpi_add(struct acpi_device *device)
 		return -ENOMEM;
 	}
 
-	memcpy_fromio(&pa, &priv->cca->cmd_pa, 8);
-	pa = le64_to_cpu(pa);
+	pa = ((u64) le32_to_cpu(ioread32(&priv->cca->cmd_pa_high)) << 32) +
+		(u64) le32_to_cpu(ioread32(&priv->cca->cmd_pa_low));
 	priv->cmd = devm_ioremap_nocache(dev, pa,
 					 ioread32(&priv->cca->cmd_size));
 	if (!priv->cmd) {
-- 
2.5.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [next] | [standalone]

#1234734

Hi,
is this for stable as well?
Since when?

I'll take care of all the patches next week when coming back to germany.

Peter
-- 
Sent from my mobile
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1234765 — Re: [PATCH] tpm, tpm_crb: fix unaligned read of the command buffer address

Hi Peter,

On Mon, Sep 28, 2015 at 11:12:59PM -0700, Peter Huewe wrote:
> Hi,
> is this for stable as well?
> Since when?
> 
> I'll take care of all the patches next week when coming back to germany.

This is definitely also for the stable.

> Peter

/Jarkko
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web