Input: reduce raciness when input handlers disconnect

There is a race between input handler's release() and disconnect()
methods: when input handler disconnects it wakes up all regular
users and then process to walk user list to wake up async. users.
While disconnect() walks the list release() removes elements of
the same list causing oopses.

While this is not a substibute for proper locking we can reduce
odds of getting an oops if we wake up normal readers after walking
the list.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Dmitry Torokhov 2007-06-03 23:29:36 -04:00
parent 26be5a509a
commit 1dfa281240
4 changed files with 4 additions and 4 deletions

View File

@ -700,9 +700,9 @@ static void evdev_disconnect(struct input_handle *handle)
if (evdev->open) {
input_flush_device(handle, NULL);
input_close_device(handle);
wake_up_interruptible(&evdev->wait);
list_for_each_entry(client, &evdev->client_list, node)
kill_fasync(&client->fasync, SIGIO, POLL_HUP);
wake_up_interruptible(&evdev->wait);
} else
evdev_free(evdev);
}

View File

@ -595,9 +595,9 @@ static void joydev_disconnect(struct input_handle *handle)
if (joydev->open) {
input_close_device(handle);
wake_up_interruptible(&joydev->wait);
list_for_each_entry(client, &joydev->client_list, node)
kill_fasync(&client->fasync, SIGIO, POLL_HUP);
wake_up_interruptible(&joydev->wait);
} else
joydev_free(joydev);
}

View File

@ -767,9 +767,9 @@ static void mousedev_disconnect(struct input_handle *handle)
if (mousedev->open) {
input_close_device(handle);
wake_up_interruptible(&mousedev->wait);
list_for_each_entry(client, &mousedev->client_list, node)
kill_fasync(&client->fasync, SIGIO, POLL_HUP);
wake_up_interruptible(&mousedev->wait);
} else
mousedev_free(mousedev);
}

View File

@ -477,9 +477,9 @@ static void tsdev_disconnect(struct input_handle *handle)
if (tsdev->open) {
input_close_device(handle);
wake_up_interruptible(&tsdev->wait);
list_for_each_entry(client, &tsdev->client_list, node)
kill_fasync(&client->fasync, SIGIO, POLL_HUP);
wake_up_interruptible(&tsdev->wait);
} else
tsdev_free(tsdev);
}