Before this, it wrote as much as available into the buffer, even if it didn't fit. Fixes: b84a8dee23fd ("usb: gadget: add Faraday fotg210_udc driver") Signed-off-by: Fabian Vogt <fabian@xxxxxxxxxxxxxx> --- drivers/usb/gadget/udc/fotg210-udc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/udc/fotg210-udc.c b/drivers/usb/gadget/udc/fotg210-udc.c index 6a4c60d5b2c2..7716bd1c8753 100644 --- a/drivers/usb/gadget/udc/fotg210-udc.c +++ b/drivers/usb/gadget/udc/fotg210-udc.c @@ -338,8 +338,9 @@ static void fotg210_start_dma(struct fotg210_ep *ep, } else { buffer = req->req.buf + req->req.actual; length = ioread32(ep->fotg210->reg + - FOTG210_FIBCR(ep->epnum - 1)); - length &= FIBCR_BCFX; + FOTG210_FIBCR(ep->epnum - 1)) & FIBCR_BCFX; + if (length > req->req.length - req->req.actual) + length = req->req.length - req->req.actual; } } else { buffer = req->req.buf + req->req.actual; -- 2.25.1