They must return the number of bytes transferred during the data stage. Fixes: 068fbff4f860 ("usb: raw-gadget: Fix copy_to/from_user() checks") Fixes: f2c2e717642c ("usb: gadget: add raw-gadget interface") Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> --- drivers/usb/gadget/legacy/raw_gadget.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c index ca7d95bf7397..7b241992ad5a 100644 --- a/drivers/usb/gadget/legacy/raw_gadget.c +++ b/drivers/usb/gadget/legacy/raw_gadget.c @@ -669,12 +669,14 @@ static int raw_ioctl_ep0_read(struct raw_dev *dev, unsigned long value) if (IS_ERR(data)) return PTR_ERR(data); ret = raw_process_ep0_io(dev, &io, data, false); - if (ret) + if (ret < 0) goto free; length = min(io.length, (unsigned int)ret); if (copy_to_user((void __user *)(value + sizeof(io)), data, length)) ret = -EFAULT; + else + ret = length; free: kfree(data); return ret; @@ -964,12 +966,14 @@ static int raw_ioctl_ep_read(struct raw_dev *dev, unsigned long value) if (IS_ERR(data)) return PTR_ERR(data); ret = raw_process_ep_io(dev, &io, data, false); - if (ret) + if (ret < 0) goto free; length = min(io.length, (unsigned int)ret); if (copy_to_user((void __user *)(value + sizeof(io)), data, length)) ret = -EFAULT; + else + ret = length; free: kfree(data); return ret; -- 2.26.2.526.g744177e7f7-goog