linux/drivers/char/tpm/tpm_of.c
Jason Gunthorpe 0cf577a03f tpm: Fix handling of missing event log
The event log is an optional firmware feature, if the firmware
does not support it then the securityfs files should not be created
and no other notification given.

- Uniformly return -ENODEV from the tpm_bios_log_setup cone if
  no event log is detected.
- Check in ACPI if this node was discovered via ACPI.
- Improve the check in OF to make sure there is a parent and to
  fail detection if the two log properties are not declared
- Pass through all other error codes instead of filtering just some

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2016-11-28 01:31:32 +02:00

59 lines
1.4 KiB
C

/*
* Copyright 2012 IBM Corporation
*
* Author: Ashley Lai <ashleydlai@gmail.com>
* Nayna Jain <nayna@linux.vnet.ibm.com>
*
* Maintained by: <tpmdd-devel@lists.sourceforge.net>
*
* Read the event log created by the firmware on PPC64
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <linux/slab.h>
#include <linux/of.h>
#include "tpm.h"
#include "tpm_eventlog.h"
int tpm_read_log_of(struct tpm_chip *chip)
{
struct device_node *np;
const u32 *sizep;
const u64 *basep;
struct tpm_bios_log *log;
log = &chip->log;
if (chip->dev.parent && chip->dev.parent->of_node)
np = chip->dev.parent->of_node;
else
return -ENODEV;
sizep = of_get_property(np, "linux,sml-size", NULL);
basep = of_get_property(np, "linux,sml-base", NULL);
if (sizep == NULL && basep == NULL)
return -ENODEV;
if (sizep == NULL || basep == NULL)
return -EIO;
if (*sizep == 0) {
dev_warn(&chip->dev, "%s: Event log area empty\n", __func__);
return -EIO;
}
log->bios_event_log = kmalloc(*sizep, GFP_KERNEL);
if (!log->bios_event_log)
return -ENOMEM;
log->bios_event_log_end = log->bios_event_log + *sizep;
memcpy(log->bios_event_log, __va(*basep), *sizep);
return 0;
}