diff options
| author | Dima Zavin <dima@android.com> | 2011-12-13 01:20:02 +0800 |
|---|---|---|
| committer | Andy Green <andy.green@linaro.org> | 2012-01-09 10:46:44 +0800 |
| commit | 9df86827c50784818f6862482394c44f3925eed8 (patch) | |
| tree | 5414f59568ba733ec60effcd6857a89a658c4a38 /drivers/input | |
| parent | 82da23456e97d440920d5cf68e71198d012db69f (diff) | |
input: evdev: only allow reading events if a full packet is present
Without this, it was possible for the reader to get ahead of packet_head.
If the the input device generated a partial packet *right* after the
reader got ahead, then we can get into a situation where the device is
marked readable but read always returns 0 until the next packet is
finished (i.e a SYN is generated by the input driver).
This situation can also happen if we overflow the buffer while a reader
is trying to read an event out.
Change-Id: If01ab371bc7de1bf1f90c122dcc5a29242b01a09
Signed-off-by: Dima Zavin <dima@android.com>
Diffstat (limited to 'drivers/input')
| -rw-r--r-- | drivers/input/evdev.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c index 07b6c815391..13a741ae604 100644 --- a/drivers/input/evdev.c +++ b/drivers/input/evdev.c @@ -381,7 +381,7 @@ static int evdev_fetch_next_event(struct evdev_client *client, spin_lock_irq(&client->buffer_lock); - have_event = client->head != client->tail; + have_event = client->packet_head != client->tail; if (have_event) { *event = client->buffer[client->tail++]; client->tail &= client->bufsize - 1; |