Patch "tpm, tpm_crb: fail when TPM2 ACPI table contents look corrupted" has been added to the 4.1-stable tree

This is a note to let you know that I've just added the patch titled

tpm, tpm_crb: fail when TPM2 ACPI table contents look corrupted

to the 4.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
tpm-tpm_crb-fail-when-tpm2-acpi-table-contents-look-corrupted.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Jarkko Sakkinen <[email protected]>
Date: Wed, 24 Jun 2015 17:14:55 +0300
Subject: tpm, tpm_crb: fail when TPM2 ACPI table contents look corrupted

From: Jarkko Sakkinen <[email protected]>

commit b371616b8537d6450ebca0819defbf53452bebf3 upstream.

At least some versions of AMI BIOS have corrupted contents in the TPM2 ACPI table and namely the physical address of the control area is set to zero.

This patch changes the driver to fail gracefully when we observe a zero address instead of continuing to ioremap.

---
 drivers/char/tpm/tpm_crb.c |    8 ++++++++
 1 file changed, 8 insertions(+)

@@ -233,6 +233,14 @@ static int crb_acpi_add(struct acpi_devi
 		return -ENODEV;
 	}
 
+	/* At least some versions of AMI BIOS have a bug that TPM2 table has
+	 * zero address for the control area and therefore we must fail.
+	*/
+	if (!buf->control_area_pa) {
+		dev_err(dev, "TPM2 ACPI table has a zero address for the control area\n");
+		return -EINVAL;
+	}
+
 	if (buf->hdr.length < sizeof(struct acpi_tpm2)) {
 		dev_err(dev, "TPM2 ACPI table has wrong size");
 		return -EINVAL;

Patches currently in stable-queue which might be from [email protected] are

queue-4.1/tpm-tpm_crb-fail-when-tpm2-acpi-table-contents-look-corrupted.patch queue-4.1/tpm-tpm_crb-fix-le64_to_cpu-conversions-in-crb_acpi_add.patch queue-4.1/tpm-fix-initialization-of-the-cdev.patch