From b57b08e6f431348363adffa5b6643fe3ec9dc7fe Mon Sep 17 00:00:00 2001
From: Jeff Vanhoof <qjv001@motorola.com>
Date: Tue, 18 Oct 2022 16:50:40 -0500
Subject: [PATCH] usb: gadget: uvc: fix sg handling during video encode
In uvc_video_encode_isoc_sg, the uvc_request's sg list is
incorrectly being populated leading to corrupt video being
received by the remote end. When building the sg list the
usage of buf->sg's 'dma_length' field is not correct and
instead its 'length' field should be used.
Fixes: e81e7f9a0eb9 ("usb: gadget: uvc: add scatter gather support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jeff Vanhoof <qjv001@motorola.com>
Signed-off-by: Dan Vacura <w36195@motorola.com>
Link: https://lore.kernel.org/r/20221018215044.765044-5-w36195@motorola.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/gadget/function/uvc_video.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c
index 5993e083819cb..dd1c6b2ca7c6f 100644
--- a/drivers/usb/gadget/function/uvc_video.c
+++ b/drivers/usb/gadget/function/uvc_video.c
@@ -157,10 +157,10 @@ uvc_video_encode_isoc_sg(struct usb_request *req, struct uvc_video *video,
sg = sg_next(sg);
for_each_sg(sg, iter, ureq->sgt.nents - 1, i) {
- if (!len || !buf->sg || !sg_dma_len(buf->sg))
+ if (!len || !buf->sg || !buf->sg->length)
break;
- sg_left = sg_dma_len(buf->sg) - buf->offset;
+ sg_left = buf->sg->length - buf->offset;
part = min_t(unsigned int, len, sg_left);
sg_set_page(iter, sg_page(buf->sg), part, buf->offset);
--
2.30.2