mei: fix mismatch in mutex unlock-lock in mei_amthif_read()

Users of mei_amthif_read() expect it leaves dev->device_lock held,
while there is a path where mei_amthif_read() unlocks device_lock
and returns -ERESTARTSYS.

The patch move code locking device_lock back before the return.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alexey Khoroshilov 2012-12-22 01:44:16 +04:00 committed by Greg Kroah-Hartman
parent d1c3ed669a
commit e6028db014

View File

@ -187,13 +187,13 @@ int mei_amthif_read(struct mei_device *dev, struct file *file,
wait_ret = wait_event_interruptible(dev->iamthif_cl.wait,
(cb = mei_amthif_find_read_list_entry(dev, file)));
/* Locking again the Mutex */
mutex_lock(&dev->device_lock);
if (wait_ret)
return -ERESTARTSYS;
dev_dbg(&dev->pdev->dev, "woke up from sleep\n");
/* Locking again the Mutex */
mutex_lock(&dev->device_lock);
}