HID: hid-bigbenff: fix race condition for scheduled work during removal

It's possible that there is scheduled work left while the device is
already being removed, which can cause a kernel crash. Adding a flag
will avoid this.

Signed-off-by: Hanno Zulla <kontakt@hanno.de>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
This commit is contained in:
Hanno Zulla 2020-02-18 12:39:31 +01:00 committed by Benjamin Tissoires
parent 976a54d0f4
commit 4eb1b01de5

View File

@ -174,6 +174,7 @@ static __u8 pid0902_rdesc_fixed[] = {
struct bigben_device {
struct hid_device *hid;
struct hid_report *report;
bool removed;
u8 led_state; /* LED1 = 1 .. LED4 = 8 */
u8 right_motor_on; /* right motor off/on 0/1 */
u8 left_motor_force; /* left motor force 0-255 */
@ -190,6 +191,9 @@ static void bigben_worker(struct work_struct *work)
struct bigben_device, worker);
struct hid_field *report_field = bigben->report->field[0];
if (bigben->removed)
return;
if (bigben->work_led) {
bigben->work_led = false;
report_field->value[0] = 0x01; /* 1 = led message */
@ -304,6 +308,7 @@ static void bigben_remove(struct hid_device *hid)
{
struct bigben_device *bigben = hid_get_drvdata(hid);
bigben->removed = true;
cancel_work_sync(&bigben->worker);
hid_hw_stop(hid);
}
@ -324,6 +329,7 @@ static int bigben_probe(struct hid_device *hid,
return -ENOMEM;
hid_set_drvdata(hid, bigben);
bigben->hid = hid;
bigben->removed = false;
error = hid_parse(hid);
if (error) {