From 183a1fcfd801a204c86edfbf55c2b902cc028007 Mon Sep 17 00:00:00 2001 From: Dima Zavin Date: Tue, 4 Oct 2011 17:10:45 -0700 Subject: [PATCH] input: evdev: do not block waiting for an event if fd is nonblock If there is a full packet in the buffer, and we overflow that buffer right after checking for that condition, it would have been possible for us to block indefinitely (rather, until the next full packet) even if the file was marked as O_NONBLOCK. Change-Id: Icd0f59f8cc98392be4c4d13bd45b5cf94317eb5a Signed-off-by: Dima Zavin --- drivers/input/evdev.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c index 10ae1c966a35..5c5f9db28075 100644 --- a/drivers/input/evdev.c +++ b/drivers/input/evdev.c @@ -405,14 +405,12 @@ static ssize_t evdev_read(struct file *file, char __user *buffer, if (count < input_event_size()) return -EINVAL; - if (client->packet_head == client->tail && evdev->exist && - (file->f_flags & O_NONBLOCK)) - return -EAGAIN; - - retval = wait_event_interruptible(evdev->wait, - client->packet_head != client->tail || !evdev->exist); - if (retval) - return retval; + if (!(file->f_flags & O_NONBLOCK)) { + retval = wait_event_interruptible(evdev->wait, + client->packet_head != client->tail || !evdev->exist); + if (retval) + return retval; + } if (!evdev->exist) return -ENODEV; -- 2.34.1