tpm_tis: Use timeouts returned from TPM

commit 9b29050f8f75916f974a2d231ae5d3cd59792296 upstream.

The current TPM TIS driver in git discards the timeout values returned
from the TPM. The check of the response packet needs to consider that
the return_code field is 0 on success and the size of the expected
packet is equivalent to the header size + u32 length indicator for the
TPM_GetCapability() result + 3 timeout indicators of type u32.

I am also adding a sysfs entry 'timeouts' showing the timeouts that are
being used.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Tested-by: Guillaume Chazarain <guichaz@gmail.com>
Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 4baed0f9485da962b5c079e5b502c527270509f7..2ec5f33cdbd021e4e074ff76e3d2e655bfcfeb7e 100644 (file)
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -567,9 +567,11 @@ duration:
        if (rc)
                return;
 
-       if (be32_to_cpu(tpm_cmd.header.out.return_code)
-           != 3 * sizeof(u32))
+       if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
+           be32_to_cpu(tpm_cmd.header.out.length)
+           != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
                return;
+
        duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
        chip->vendor.duration[TPM_SHORT] =
            usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
@@ -913,6 +915,18 @@ ssize_t tpm_show_caps_1_2(struct device * dev,
 }
 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 
+ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
+                         char *buf)
+{
+       struct tpm_chip *chip = dev_get_drvdata(dev);
+
+       return sprintf(buf, "%d %d %d\n",
+                      jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
+                      jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
+                      jiffies_to_usecs(chip->vendor.duration[TPM_LONG]));
+}
+EXPORT_SYMBOL_GPL(tpm_show_timeouts);
+
 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
                        const char *buf, size_t count)
 {

diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 792868d24f2a0f2ad6bc21a4967ace01a2f84d92..ba1779c2cffd553f7dc8edca6a89a23d164520b6 100644 (file)
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -56,6 +56,8 @@ extern ssize_t tpm_show_owned(struct device *, struct device_attribute *attr,
                                char *);
 extern ssize_t tpm_show_temp_deactivated(struct device *,
                                         struct device_attribute *attr, char *);
+extern ssize_t tpm_show_timeouts(struct device *,
+                                struct device_attribute *attr, char *);
 
 struct tpm_chip;
 

diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index 1030f8420137adb8ff7363eb259f9578026fe178..ef9c4acf88e4b50b99b02da1f2fc4d3537576d61 100644 (file)
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -355,6 +355,7 @@ static DEVICE_ATTR(temp_deactivated, S_IRUGO, tpm_show_temp_deactivated,
                   NULL);
 static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps_1_2, NULL);
 static DEVICE_ATTR(cancel, S_IWUSR | S_IWGRP, NULL, tpm_store_cancel);
+static DEVICE_ATTR(timeouts, S_IRUGO, tpm_show_timeouts, NULL);
 
 static struct attribute *tis_attrs[] = {
        &dev_attr_pubek.attr,
@@ -364,7 +365,8 @@ static struct attribute *tis_attrs[] = {
        &dev_attr_owned.attr,
        &dev_attr_temp_deactivated.attr,
        &dev_attr_caps.attr,
-       &dev_attr_cancel.attr, NULL,
+       &dev_attr_cancel.attr,
+       &dev_attr_timeouts.attr, NULL,
 };
 
 static struct attribute_group tis_attr_grp = {