TPM: integrity fix
Fix to function which is called by IMA, now tpm_chip_find_get() considers the case in which the machine doesn't have a TPM or, if it has, its TPM isn't enabled.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 62a5682..ccdd828 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -666,18 +666,20 @@
*/
static struct tpm_chip *tpm_chip_find_get(int chip_num)
{
- struct tpm_chip *pos;
+ struct tpm_chip *pos, *chip = NULL;
rcu_read_lock();
list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
continue;
- if (try_module_get(pos->dev->driver->owner))
+ if (try_module_get(pos->dev->driver->owner)) {
+ chip = pos;
break;
+ }
}
rcu_read_unlock();
- return pos;
+ return chip;
}
#define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
