mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Guangshuo Li <lgs201920130244@gmail.com>
Cc: Jacopo Mondi <jacopo@jmondi.org>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Hans Verkuil <hverkuil@kernel.org>,
	linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] media: renesas: ceu: free device data if video device is unregistered
Date: Tue, 29 Sep 2026 15:16:02 +0300	[thread overview]
Message-ID: <20260929121602.GG171869@killaraus.ideasonboard.com> (raw)
In-Reply-To: <20260915135406.2423337-1-lgs201920130244@gmail.com>

On Tue, Sep 15, 2026 at 09:54:06PM +0800, Guangshuo Li wrote:
> ceu_probe() allocates ceudev, while ceu_remove() does not free it if the
> video device has not been registered.
> 
> The video device is registered from the async notifier complete
> callback, and its release callback is responsible for freeing ceudev.
> If the device is removed before the notifier completes, or before video
> device registration succeeds, video_unregister_device() does not invoke
> the release callback and the ceudev allocation is leaked.
> 
> Check whether the video device was registered during remove. Unregister
> it normally when registered so that its release callback handles the
> final free, otherwise free ceudev directly.
> 
> This issue was found by manual code inspection.

That's hard to believe.

How have you tested this patch ?

> Fixes: 32e5a70dc8f4 ("media: platform: Add Renesas CEU driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
> ---
>  drivers/media/platform/renesas/renesas-ceu.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/platform/renesas/renesas-ceu.c b/drivers/media/platform/renesas/renesas-ceu.c
> index 65f7659a9e02..5015b7837381 100644
> --- a/drivers/media/platform/renesas/renesas-ceu.c
> +++ b/drivers/media/platform/renesas/renesas-ceu.c
> @@ -1705,7 +1705,10 @@ static void ceu_remove(struct platform_device *pdev)
>  
>  	v4l2_device_unregister(&ceudev->v4l2_dev);
>  
> -	video_unregister_device(&ceudev->vdev);
> +	if (video_is_registered(&ceudev->vdev))
> +		video_unregister_device(&ceudev->vdev);
> +	else
> +		kfree(ceudev);
>  }
>  
>  static const struct dev_pm_ops ceu_pm_ops = {

-- 
Regards,

Laurent Pinchart

      reply	other threads:[~2026-09-29 12:16 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-15 13:54 Guangshuo Li
2026-09-29 12:16 ` Laurent Pinchart [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260929121602.GG171869@killaraus.ideasonboard.com \
    --to=laurent.pinchart@ideasonboard.com \
    --cc=hverkuil@kernel.org \
    --cc=jacopo@jmondi.org \
    --cc=lgs201920130244@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-renesas-soc@vger.kernel.org \
    --cc=mchehab@kernel.org \
    --cc=stable@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®