ACPI: fix create_modalias() return value handling

Currently, create_modalias() handles the output truncated case in
an improper way (return -EINVAL).
Plus, acpi_device_uevent() and acpi_device_modalias_show() do
improper check for the create_modalias() return value as well.

This patch fixes create_modalias() to
return -EINVAL if there is an output error,
return -ENOMEM if the output is truncated,
and also fixes both acpi_device_uevent() and acpi_device_modalias_show()
to do proper return value check.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Zhang Rui 2014-01-14 16:46:35 +08:00 committed by Rafael J. Wysocki
parent 7e22e91102
commit 3d8e00909d

View file

@ -85,6 +85,9 @@ int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
* Creates hid/cid(s) string needed for modalias and uevent
* e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
* char *modalias: "acpi:IBM0001:ACPI0001"
* Return: 0: no _HID and no _CID
* -EINVAL: output error
* -ENOMEM: output is truncated
*/
static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
int size)
@ -101,8 +104,10 @@ static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
count = snprintf(&modalias[len], size, "%s:", id->id);
if (count < 0 || count >= size)
return -EINVAL;
if (count < 0)
return EINVAL;
if (count >= size)
return -ENOMEM;
len += count;
size -= count;
}
@ -116,10 +121,9 @@ acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, cha
struct acpi_device *acpi_dev = to_acpi_device(dev);
int len;
/* Device has no HID and no CID or string is >1024 */
len = create_modalias(acpi_dev, buf, 1024);
if (len <= 0)
return 0;
return len;
buf[len++] = '\n';
return len;
}
@ -782,8 +786,8 @@ static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
return -ENOMEM;
len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
sizeof(env->buf) - env->buflen);
if (len >= (sizeof(env->buf) - env->buflen))
return -ENOMEM;
if (len <= 0)
return len;
env->buflen += len;
return 0;
}