From: Binyamin Sharet Date: Thu, 7 Jul 2016 19:22:04 +0000 (+0300) Subject: usb: gadget: fix check in sync read from ep in gadgetfs X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=63196e989699ddffb4e3d30ca8c3567d408820f4;p=linux-beck.git 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 Signed-off-by: Felipe Balbi --- diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c index aa3707bdebb4..8560f2fe3af5 100644 --- a/drivers/usb/gadget/legacy/inode.c +++ b/drivers/usb/gadget/legacy/inode.c @@ -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);