From: Robin Guo <guoweibin@xxxxxxxxxx> [ Upstream commit eea4c860c3b366369eff0489d94ee4f0571d467d ] The usb function device call musb_gadget_queue() adds the passed request to musb_ep::req_list,If the (request->length > musb_ep->packet_sz) and (is_buffer_mapped(req) return false),the rxstate() will copy all data in fifo to request->buf which may cause request->buf out of bounds. Fix it by add the length check : fifocnt = min_t(unsigned, request->length - request->actual, fifocnt); Signed-off-by: Robin Guo <guoweibin@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220906102119.1b071d07a8391ff115e6d1ef@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/usb/musb/musb_gadget.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c index 8eb3a291ca9d..02ec84ce5ab9 100644 --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -785,6 +785,9 @@ static void rxstate(struct musb *musb, struct musb_request *req) musb_writew(epio, MUSB_RXCSR, csr); buffer_aint_mapped: + fifo_count = min_t(unsigned int, + request->length - request->actual, + (unsigned int)fifo_count); musb_read_fifo(musb_ep->hw_ep, fifo_count, (u8 *) (request->buf + request->actual)); request->actual += fifo_count; -- 2.35.1