From: Valery Borovsky Date: Mon, 11 May 2026 17:12:08 +0000 (+0300) Subject: media: pwc: Return queued buffers on start_streaming() failure X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=975b2ee20e569d47821e4f6c9761b4664d48a6a4;p=thirdparty%2Fkernel%2Flinux.git media: pwc: Return queued buffers on start_streaming() failure The vb2 framework hands buffers to the driver via buf_queue() before calling start_streaming(). If start_streaming() returns an error without first returning those buffers via vb2_buffer_done(), vb2_start_streaming() fires WARN_ON(owned_by_drv_count) and the queued buffers leak. pwc's start_streaming() had two early returns that hit this trap: -ENODEV when the USB device was already disconnected, and -ERESTARTSYS when mutex_lock_interruptible() was interrupted by a signal. Call the existing pwc_cleanup_queued_bufs() helper with VB2_BUF_STATE_QUEUED before returning (matching the state already used by the pwc_isoc_init() error path in the same function). This mirrors the uvcvideo fix in commit 4cf3b6fd54eb ("media: uvcvideo: Return queued buffers on start_streaming() failure"). Fixes: ceede9fa8939 ("[media] pwc: Fix locking") Cc: stable@vger.kernel.org Signed-off-by: Valery Borovsky Signed-off-by: Hans Verkuil --- diff --git a/drivers/media/usb/pwc/pwc-if.c b/drivers/media/usb/pwc/pwc-if.c index c416e2fc5754..59b99ac8fcb6 100644 --- a/drivers/media/usb/pwc/pwc-if.c +++ b/drivers/media/usb/pwc/pwc-if.c @@ -710,11 +710,15 @@ static int start_streaming(struct vb2_queue *vq, unsigned int count) struct pwc_device *pdev = vb2_get_drv_priv(vq); int r; - if (!pdev->udev) + if (!pdev->udev) { + pwc_cleanup_queued_bufs(pdev, VB2_BUF_STATE_QUEUED); return -ENODEV; + } - if (mutex_lock_interruptible(&pdev->v4l2_lock)) + if (mutex_lock_interruptible(&pdev->v4l2_lock)) { + pwc_cleanup_queued_bufs(pdev, VB2_BUF_STATE_QUEUED); return -ERESTARTSYS; + } /* Turn on camera and set LEDS on */ pwc_camera_power(pdev, 1); pwc_set_leds(pdev, leds[0], leds[1]);