From: Fabian Vogt <fabian@xxxxxxxxxxxxxx> [ Upstream commit 755915fc28edfc608fa89a163014acb2f31c1e19 ] For a 75 Byte request, it would send the first 64 separately, then detect that the remaining 11 Byte fit into a single DMA, but due to this bug set the length to the original 75 Bytes. This leads to a DMA failure (which is ignored...) and the request completes without the remaining bytes having been sent. Fixes: b84a8dee23fd ("usb: gadget: add Faraday fotg210_udc driver") Signed-off-by: Fabian Vogt <fabian@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210324141115.9384-2-fabian@xxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/usb/gadget/udc/fotg210-udc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/gadget/udc/fotg210-udc.c b/drivers/usb/gadget/udc/fotg210-udc.c index bc6abaea907d..d698d4ab121b 100644 --- a/drivers/usb/gadget/udc/fotg210-udc.c +++ b/drivers/usb/gadget/udc/fotg210-udc.c @@ -345,7 +345,7 @@ static void fotg210_start_dma(struct fotg210_ep *ep, if (req->req.length - req->req.actual > ep->ep.maxpacket) length = ep->ep.maxpacket; else - length = req->req.length; + length = req->req.length - req->req.actual; } d = dma_map_single(NULL, buffer, length, -- 2.30.2