From 80ff4ef777374188377abdff9623878b89edf287 Mon Sep 17 00:00:00 2001 From: Dan Vacura Date: Tue, 18 Oct 2022 16:50:39 -0500 Subject: [PATCH] usb: gadget: uvc: fix sg handling in error case 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: Signed-off-by: Dan Vacura Link: https://lore.kernel.org/r/20221018215044.765044-4-w36195@motorola.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/uvc_queue.c | 8 +++++--- drivers/usb/gadget/function/uvc_video.c | 18 ++++++++++++++---- 2 files changed, 19 insertions(+), 7 deletions(-) diff --git a/drivers/usb/gadget/function/uvc_queue.c b/drivers/usb/gadget/function/uvc_queue.c index ec299f5cc65a..0cc8422afe4e 100644 --- a/drivers/usb/gadget/function/uvc_queue.c +++ b/drivers/usb/gadget/function/uvc_queue.c @@ -313,6 +313,7 @@ int uvcg_queue_enable(struct uvc_video_queue *queue, int enable) 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) @@ -338,10 +339,11 @@ int uvcg_queue_enable(struct uvc_video_queue *queue, int enable) 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; } diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c index 1889d75f8788..15e2202cf203 100644 --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -59,6 +59,7 @@ uvc_video_encode_bulk(struct usb_request *req, struct uvc_video *video, struct uvc_buffer *buf) { void *mem = req->buf; + struct uvc_request *ureq = req->context; int len = video->req_size; int ret; @@ -84,13 +85,14 @@ uvc_video_encode_bulk(struct usb_request *req, struct uvc_video *video, 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; } @@ -151,7 +153,8 @@ uvc_video_encode_isoc_sg(struct usb_request *req, struct uvc_video *video, 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; @@ -166,6 +169,7 @@ uvc_video_encode_isoc(struct usb_request *req, struct uvc_video *video, struct uvc_buffer *buf) { void *mem = req->buf; + struct uvc_request *ureq = req->context; int len = video->req_size; int ret; @@ -180,12 +184,13 @@ uvc_video_encode_isoc(struct usb_request *req, struct uvc_video *video, 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; } } @@ -222,6 +227,11 @@ uvc_video_complete(struct usb_ep *ep, struct usb_request *req) 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);