@@ -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;
}
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> --- drivers/acpi/scan.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-)