linux-kernel - Re: [PATCH v2 01/10] media: v4l2-ctrls: Add missing v4l2 ctrl unlock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <47861cbd-e385-66c0-798d-f6ff3f454bac@xs4all.nl>
Date:   Fri, 20 Apr 2018 15:38:32 +0200
From:   Hans Verkuil <hverkuil@...all.nl>
To:     Paul Kocialkowski <paul.kocialkowski@...tlin.com>,
        linux-media@...r.kernel.org, devicetree@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-sunxi@...glegroups.com
Cc:     Mauro Carvalho Chehab <mchehab@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Maxime Ripard <maxime.ripard@...tlin.com>,
        Chen-Yu Tsai <wens@...e.org>, Pawel Osciak <pawel@...iak.com>,
        Marek Szyprowski <m.szyprowski@...sung.com>,
        Kyungmin Park <kyungmin.park@...sung.com>,
        Hans Verkuil <hans.verkuil@...co.com>,
        Sakari Ailus <sakari.ailus@...ux.intel.com>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        Arnd Bergmann <arnd@...db.de>,
        Alexandre Courbot <acourbot@...omium.org>,
        Tomasz Figa <tfiga@...omium.org>
Subject: Re: [PATCH v2 01/10] media: v4l2-ctrls: Add missing v4l2 ctrl unlock

On 04/19/18 17:41, Paul Kocialkowski wrote:
> This adds a missing v4l2_ctrl_unlock call that is required to avoid
> deadlocks.
> 
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@...tlin.com>
> ---
>  drivers/media/v4l2-core/v4l2-ctrls.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
> index f67e9f5531fa..ba05a8b9a095 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
> @@ -3614,10 +3614,12 @@ void v4l2_ctrl_request_complete(struct media_request *req,
>  			continue;
>  
>  		v4l2_ctrl_lock(ctrl);
> +
>  		if (ref->req)
>  			ptr_to_ptr(ctrl, ref->req->p_req, ref->p_req);
>  		else
>  			ptr_to_ptr(ctrl, ctrl->p_cur, ref->p_req);
> +
>  		v4l2_ctrl_unlock(ctrl);
>  	}
>  
> @@ -3677,8 +3679,11 @@ void v4l2_ctrl_request_setup(struct media_request *req,
>  				}
>  			}
>  		}
> -		if (!have_new_data)
> +
> +		if (!have_new_data) {
> +			v4l2_ctrl_unlock(master);
>  			continue;
> +		}

Oops! Thanks for finding this. I'll fold this into the relevant patch in my tree.

>  
>  		for (i = 0; i < master->ncontrols; i++) {
>  			if (master->cluster[i]) {
> 

Regards,

	Hans