diff options
| author | Jann Horn <jannh@google.com> | 2022-01-14 16:33:31 +0300 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2022-01-19 17:59:05 +0300 |
| commit | c8e7ff41f819b0c31c66c5196933c26c18f7681f (patch) | |
| tree | 3f1835897eb97677157348baaadc41e03295d1f2 | |
| parent | 4ea5763fb79ed89b3bdad455ebf3f33416a81624 (diff) | |
| download | linux-c8e7ff41f819b0c31c66c5196933c26c18f7681f.tar.xz | |
HID: uhid: Use READ_ONCE()/WRITE_ONCE() for ->running
The flag uhid->running can be set to false by uhid_device_add_worker()
without holding the uhid->devlock. Mark all reads/writes of the flag
that might race with READ_ONCE()/WRITE_ONCE() for clarity and
correctness.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| -rw-r--r-- | drivers/hid/uhid.c | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/drivers/hid/uhid.c b/drivers/hid/uhid.c index fc06d8bb42e0..614adb510dbd 100644 --- a/drivers/hid/uhid.c +++ b/drivers/hid/uhid.c @@ -84,7 +84,7 @@ static void uhid_device_add_worker(struct work_struct *work) * However, we do have to clear the ->running flag and do a * wakeup to make sure userspace knows that the device is gone. */ - uhid->running = false; + WRITE_ONCE(uhid->running, false); wake_up_interruptible(&uhid->report_wait); } } @@ -194,9 +194,9 @@ static int __uhid_report_queue_and_wait(struct uhid_device *uhid, spin_unlock_irqrestore(&uhid->qlock, flags); ret = wait_event_interruptible_timeout(uhid->report_wait, - !uhid->report_running || !uhid->running, + !uhid->report_running || !READ_ONCE(uhid->running), 5 * HZ); - if (!ret || !uhid->running || uhid->report_running) + if (!ret || !READ_ONCE(uhid->running) || uhid->report_running) ret = -EIO; else if (ret < 0) ret = -ERESTARTSYS; @@ -237,7 +237,7 @@ static int uhid_hid_get_report(struct hid_device *hid, unsigned char rnum, struct uhid_event *ev; int ret; - if (!uhid->running) + if (!READ_ONCE(uhid->running)) return -EIO; ev = kzalloc(sizeof(*ev), GFP_KERNEL); @@ -279,7 +279,7 @@ static int uhid_hid_set_report(struct hid_device *hid, unsigned char rnum, struct uhid_event *ev; int ret; - if (!uhid->running || count > UHID_DATA_MAX) + if (!READ_ONCE(uhid->running) || count > UHID_DATA_MAX) return -EIO; ev = kzalloc(sizeof(*ev), GFP_KERNEL); @@ -579,7 +579,7 @@ static int uhid_dev_destroy(struct uhid_device *uhid) if (!uhid->hid) return -EINVAL; - uhid->running = false; + WRITE_ONCE(uhid->running, false); wake_up_interruptible(&uhid->report_wait); cancel_work_sync(&uhid->worker); @@ -593,7 +593,7 @@ static int uhid_dev_destroy(struct uhid_device *uhid) static int uhid_dev_input(struct uhid_device *uhid, struct uhid_event *ev) { - if (!uhid->running) + if (!READ_ONCE(uhid->running)) return -EINVAL; hid_input_report(uhid->hid, HID_INPUT_REPORT, ev->u.input.data, @@ -604,7 +604,7 @@ static int uhid_dev_input(struct uhid_device *uhid, struct uhid_event *ev) static int uhid_dev_input2(struct uhid_device *uhid, struct uhid_event *ev) { - if (!uhid->running) + if (!READ_ONCE(uhid->running)) return -EINVAL; hid_input_report(uhid->hid, HID_INPUT_REPORT, ev->u.input2.data, @@ -616,7 +616,7 @@ static int uhid_dev_input2(struct uhid_device *uhid, struct uhid_event *ev) static int uhid_dev_get_report_reply(struct uhid_device *uhid, struct uhid_event *ev) { - if (!uhid->running) + if (!READ_ONCE(uhid->running)) return -EINVAL; uhid_report_wake_up(uhid, ev->u.get_report_reply.id, ev); @@ -626,7 +626,7 @@ static int uhid_dev_get_report_reply(struct uhid_device *uhid, static int uhid_dev_set_report_reply(struct uhid_device *uhid, struct uhid_event *ev) { - if (!uhid->running) + if (!READ_ONCE(uhid->running)) return -EINVAL; uhid_report_wake_up(uhid, ev->u.set_report_reply.id, ev); |