diff options
| author | Avichal Rakesh <arakesh@google.com> | 2024-01-05 00:50:09 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-01-05 12:35:57 +0300 |
| commit | 9866dc4314c6c858e451933f965d64532aec00a9 (patch) | |
| tree | 96aeb09937340fe72fc765dc635f43498e9f63c8 | |
| parent | fe814b5b0f3042f1a583734497e726ee53783cc1 (diff) | |
| download | linux-9866dc4314c6c858e451933f965d64532aec00a9.tar.xz | |
usb: gadget: uvc: Remove nested locking
When handling error status from uvcg_video_usb_req_queue,
uvc_video_complete currently calls uvcg_queue_cancel with
video->req_lock held. uvcg_queue_cancel internally locks
queue->irqlock, which nests queue->irqlock inside
video->req_lock. This isn't a functional bug at the
moment, but does open up possibilities for ABBA
deadlocks in the future.
This patch fixes the accidental nesting by dropping
video->req_lock before calling uvcg_queue_cancel.
Fixes: 6acba0345b68 ("usb:gadget:uvc Do not use worker thread to pump isoc usb requests")
Signed-off-by: Avichal Rakesh <arakesh@google.com>
Link: https://lore.kernel.org/r/20240104215009.2252452-2-arakesh@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/gadget/function/uvc_video.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c index 7f18dc471be3..dd3241fc6939 100644 --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -469,13 +469,15 @@ uvc_video_complete(struct usb_ep *ep, struct usb_request *req) * Put request back in req_free for it to be cleaned * up later. */ - uvcg_queue_cancel(queue, 0); list_add_tail(&to_queue->list, &video->req_free); } } else { uvc_video_free_request(ureq, ep); + ret = 0; } spin_unlock_irqrestore(&video->req_lock, flags); + if (ret < 0) + uvcg_queue_cancel(queue, 0); } static int |