Commit 63196e98 authored Jul 07, 2016 by Binyamin Sharet Committed by Felipe Balbi Aug 11, 2016

usb: gadget: fix check in sync read from ep in gadgetfs



When reading synchronously from a non-zero endpoint, gadgetfs will
return -EFAULT even if the read succeeds, due to a bad check of the
copy_to_iter() return value.

This fix compares the return value of copy_to_iter to the amount of
bytes that was passed, and only fails if they are not the same.

Signed-off-by: Binyamin Sharet <s.binyamin@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

parent 528d2813

drivers/usb/gadget/legacy/inode.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -606,7 +606,7 @@ ep_read_iter(struct kiocb iocb, struct iov_iter to)
		}
		if (is_sync_kiocb(iocb)) {
		value = ep_io(epdata, buf, len);
		if (value >= 0 && copy_to_iter(buf, value, to))
		if (value >= 0 && (copy_to_iter(buf, value, to) != value))
		value = -EFAULT;
		} else {
		struct kiocb_priv priv = kzalloc(sizeof priv, GFP_KERNEL);