kernel-fxtec-pro1x/drivers/acpi/glue.c
Jesper Juhl 2978af545b ACPI: Fix memory leak in acpi_bind_one()
Memory is allocated with kzalloc() and assigned to
'physical_node'. Then 'physical_node->node_id' is initialized with a
call to 'find_first_zero_bit()', if that results in a value greater
than ACPI_MAX_PHYSICAL_NODE we'll end up jumping to the 'err:' label
and there leave the function and let 'physical_node' go out of scope
and leak the memory we allocated.
This patch fixes the leak by simply freeing the unused/unneeded memory
pointed to by 'physical_node' just before we jump to 'err:'.

[rjw: The problem has been introduced by commit 1033f90 (ACPI: Allow
 ACPI binding with USB-3.0 hub), which is new in 3.7-rc.]

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-10-23 00:53:58 +02:00

298 lines
7 KiB
C

/*
* Link physical devices with ACPI devices support
*
* Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com>
* Copyright (c) 2005 Intel Corp.
*
* This file is released under the GPLv2.
*/
#include <linux/export.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/rwsem.h>
#include <linux/acpi.h>
#include "internal.h"
#define ACPI_GLUE_DEBUG 0
#if ACPI_GLUE_DEBUG
#define DBG(x...) printk(PREFIX x)
#else
#define DBG(x...) do { } while(0)
#endif
static LIST_HEAD(bus_type_list);
static DECLARE_RWSEM(bus_type_sem);
#define PHYSICAL_NODE_STRING "physical_node"
int register_acpi_bus_type(struct acpi_bus_type *type)
{
if (acpi_disabled)
return -ENODEV;
if (type && type->bus && type->find_device) {
down_write(&bus_type_sem);
list_add_tail(&type->list, &bus_type_list);
up_write(&bus_type_sem);
printk(KERN_INFO PREFIX "bus type %s registered\n",
type->bus->name);
return 0;
}
return -ENODEV;
}
EXPORT_SYMBOL_GPL(register_acpi_bus_type);
int unregister_acpi_bus_type(struct acpi_bus_type *type)
{
if (acpi_disabled)
return 0;
if (type) {
down_write(&bus_type_sem);
list_del_init(&type->list);
up_write(&bus_type_sem);
printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n",
type->bus->name);
return 0;
}
return -ENODEV;
}
EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type)
{
struct acpi_bus_type *tmp, *ret = NULL;
down_read(&bus_type_sem);
list_for_each_entry(tmp, &bus_type_list, list) {
if (tmp->bus == type) {
ret = tmp;
break;
}
}
up_read(&bus_type_sem);
return ret;
}
static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
{
struct acpi_bus_type *tmp;
int ret = -ENODEV;
down_read(&bus_type_sem);
list_for_each_entry(tmp, &bus_type_list, list) {
if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
ret = 0;
break;
}
}
up_read(&bus_type_sem);
return ret;
}
/* Get device's handler per its address under its parent */
struct acpi_find_child {
acpi_handle handle;
u64 address;
};
static acpi_status
do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
{
acpi_status status;
struct acpi_device_info *info;
struct acpi_find_child *find = context;
status = acpi_get_object_info(handle, &info);
if (ACPI_SUCCESS(status)) {
if ((info->address == find->address)
&& (info->valid & ACPI_VALID_ADR))
find->handle = handle;
kfree(info);
}
return AE_OK;
}
acpi_handle acpi_get_child(acpi_handle parent, u64 address)
{
struct acpi_find_child find = { NULL, address };
if (!parent)
return NULL;
acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
1, do_acpi_find_child, NULL, &find, NULL);
return find.handle;
}
EXPORT_SYMBOL(acpi_get_child);
static int acpi_bind_one(struct device *dev, acpi_handle handle)
{
struct acpi_device *acpi_dev;
acpi_status status;
struct acpi_device_physical_node *physical_node;
char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2];
int retval = -EINVAL;
if (dev->archdata.acpi_handle) {
dev_warn(dev, "Drivers changed 'acpi_handle'\n");
return -EINVAL;
}
get_device(dev);
status = acpi_bus_get_device(handle, &acpi_dev);
if (ACPI_FAILURE(status))
goto err;
physical_node = kzalloc(sizeof(struct acpi_device_physical_node),
GFP_KERNEL);
if (!physical_node) {
retval = -ENOMEM;
goto err;
}
mutex_lock(&acpi_dev->physical_node_lock);
/* allocate physical node id according to physical_node_id_bitmap */
physical_node->node_id =
find_first_zero_bit(acpi_dev->physical_node_id_bitmap,
ACPI_MAX_PHYSICAL_NODE);
if (physical_node->node_id >= ACPI_MAX_PHYSICAL_NODE) {
retval = -ENOSPC;
mutex_unlock(&acpi_dev->physical_node_lock);
kfree(physical_node);
goto err;
}
set_bit(physical_node->node_id, acpi_dev->physical_node_id_bitmap);
physical_node->dev = dev;
list_add_tail(&physical_node->node, &acpi_dev->physical_node_list);
acpi_dev->physical_node_count++;
mutex_unlock(&acpi_dev->physical_node_lock);
dev->archdata.acpi_handle = handle;
if (!physical_node->node_id)
strcpy(physical_node_name, PHYSICAL_NODE_STRING);
else
sprintf(physical_node_name,
"physical_node%d", physical_node->node_id);
retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
physical_node_name);
retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
"firmware_node");
if (acpi_dev->wakeup.flags.valid)
device_set_wakeup_capable(dev, true);
return 0;
err:
put_device(dev);
return retval;
}
static int acpi_unbind_one(struct device *dev)
{
struct acpi_device_physical_node *entry;
struct acpi_device *acpi_dev;
acpi_status status;
struct list_head *node, *next;
if (!dev->archdata.acpi_handle)
return 0;
status = acpi_bus_get_device(dev->archdata.acpi_handle,
&acpi_dev);
if (ACPI_FAILURE(status))
goto err;
mutex_lock(&acpi_dev->physical_node_lock);
list_for_each_safe(node, next, &acpi_dev->physical_node_list) {
char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2];
entry = list_entry(node, struct acpi_device_physical_node,
node);
if (entry->dev != dev)
continue;
list_del(node);
clear_bit(entry->node_id, acpi_dev->physical_node_id_bitmap);
acpi_dev->physical_node_count--;
if (!entry->node_id)
strcpy(physical_node_name, PHYSICAL_NODE_STRING);
else
sprintf(physical_node_name,
"physical_node%d", entry->node_id);
sysfs_remove_link(&acpi_dev->dev.kobj, physical_node_name);
sysfs_remove_link(&dev->kobj, "firmware_node");
dev->archdata.acpi_handle = NULL;
/* acpi_bind_one increase refcnt by one */
put_device(dev);
kfree(entry);
}
mutex_unlock(&acpi_dev->physical_node_lock);
return 0;
err:
dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
return -EINVAL;
}
static int acpi_platform_notify(struct device *dev)
{
struct acpi_bus_type *type;
acpi_handle handle;
int ret = -EINVAL;
if (!dev->bus || !dev->parent) {
/* bridge devices genernally haven't bus or parent */
ret = acpi_find_bridge_device(dev, &handle);
goto end;
}
type = acpi_get_bus_type(dev->bus);
if (!type) {
DBG("No ACPI bus support for %s\n", dev_name(dev));
ret = -EINVAL;
goto end;
}
if ((ret = type->find_device(dev, &handle)) != 0)
DBG("Can't get handler for %s\n", dev_name(dev));
end:
if (!ret)
acpi_bind_one(dev, handle);
#if ACPI_GLUE_DEBUG
if (!ret) {
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_get_name(dev->archdata.acpi_handle,
ACPI_FULL_PATHNAME, &buffer);
DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
kfree(buffer.pointer);
} else
DBG("Device %s -> No ACPI support\n", dev_name(dev));
#endif
return ret;
}
static int acpi_platform_notify_remove(struct device *dev)
{
acpi_unbind_one(dev);
return 0;
}
int __init init_acpi_device_notify(void)
{
if (platform_notify || platform_notify_remove) {
printk(KERN_ERR PREFIX "Can't use platform_notify\n");
return 0;
}
platform_notify = acpi_platform_notify;
platform_notify_remove = acpi_platform_notify_remove;
return 0;
}