From: Dan Vacura w36195@motorola.com
commit 0a0a2760b04814428800d48281a447a7522470ad upstream.
If there is a transmission error the buffer will be returned too early, causing a memory fault as subsequent requests for that buffer are still queued up to be sent. Refactor the error handling to wait for the final request to come in before reporting back the buffer to userspace for all transfer types (bulk/isoc/isoc_sg). This ensures userspace knows if the frame was successfully sent.
Fixes: e81e7f9a0eb9 ("usb: gadget: uvc: add scatter gather support") Cc: stable@vger.kernel.org Signed-off-by: Dan Vacura w36195@motorola.com Link: https://lore.kernel.org/r/20221018215044.765044-4-w36195@motorola.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/gadget/function/uvc_queue.c | 8 +++++--- drivers/usb/gadget/function/uvc_video.c | 18 ++++++++++++++---- 2 files changed, 19 insertions(+), 7 deletions(-)
--- a/drivers/usb/gadget/function/uvc_queue.c +++ b/drivers/usb/gadget/function/uvc_queue.c @@ -304,6 +304,7 @@ int uvcg_queue_enable(struct uvc_video_q
queue->sequence = 0; queue->buf_used = 0; + queue->flags &= ~UVC_QUEUE_DROP_INCOMPLETE; } else { ret = vb2_streamoff(&queue->queue, queue->queue.type); if (ret < 0) @@ -329,10 +330,11 @@ int uvcg_queue_enable(struct uvc_video_q void uvcg_complete_buffer(struct uvc_video_queue *queue, struct uvc_buffer *buf) { - if ((queue->flags & UVC_QUEUE_DROP_INCOMPLETE) && - buf->length != buf->bytesused) { - buf->state = UVC_BUF_STATE_QUEUED; + if (queue->flags & UVC_QUEUE_DROP_INCOMPLETE) { + queue->flags &= ~UVC_QUEUE_DROP_INCOMPLETE; + buf->state = UVC_BUF_STATE_ERROR; vb2_set_plane_payload(&buf->buf.vb2_buf, 0, 0); + vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_ERROR); return; }
--- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -88,6 +88,7 @@ uvc_video_encode_bulk(struct usb_request struct uvc_buffer *buf) { void *mem = req->buf; + struct uvc_request *ureq = req->context; int len = video->req_size; int ret;
@@ -113,13 +114,14 @@ uvc_video_encode_bulk(struct usb_request video->queue.buf_used = 0; buf->state = UVC_BUF_STATE_DONE; list_del(&buf->queue); - uvcg_complete_buffer(&video->queue, buf); video->fid ^= UVC_STREAM_FID; + ureq->last_buf = buf;
video->payload_size = 0; }
if (video->payload_size == video->max_payload_size || + video->queue.flags & UVC_QUEUE_DROP_INCOMPLETE || buf->bytesused == video->queue.buf_used) video->payload_size = 0; } @@ -180,7 +182,8 @@ uvc_video_encode_isoc_sg(struct usb_requ req->length -= len; video->queue.buf_used += req->length - header_len;
- if (buf->bytesused == video->queue.buf_used || !buf->sg) { + if (buf->bytesused == video->queue.buf_used || !buf->sg || + video->queue.flags & UVC_QUEUE_DROP_INCOMPLETE) { video->queue.buf_used = 0; buf->state = UVC_BUF_STATE_DONE; buf->offset = 0; @@ -195,6 +198,7 @@ uvc_video_encode_isoc(struct usb_request struct uvc_buffer *buf) { void *mem = req->buf; + struct uvc_request *ureq = req->context; int len = video->req_size; int ret;
@@ -209,12 +213,13 @@ uvc_video_encode_isoc(struct usb_request
req->length = video->req_size - len;
- if (buf->bytesused == video->queue.buf_used) { + if (buf->bytesused == video->queue.buf_used || + video->queue.flags & UVC_QUEUE_DROP_INCOMPLETE) { video->queue.buf_used = 0; buf->state = UVC_BUF_STATE_DONE; list_del(&buf->queue); - uvcg_complete_buffer(&video->queue, buf); video->fid ^= UVC_STREAM_FID; + ureq->last_buf = buf; } }
@@ -255,6 +260,11 @@ uvc_video_complete(struct usb_ep *ep, st case 0: break;
+ case -EXDEV: + uvcg_dbg(&video->uvc->func, "VS request missed xfer.\n"); + queue->flags |= UVC_QUEUE_DROP_INCOMPLETE; + break; + case -ESHUTDOWN: /* disconnect from host. */ uvcg_dbg(&video->uvc->func, "VS request cancelled.\n"); uvcg_queue_cancel(queue, 1);