From mboxrd@z Thu Jan  1 00:00:00 1970
From: Liviu Dudau <liviu.dudau@arm.com>
Date: Fri, 03 May 2019 14:41:14 +0000
Subject: Re: [PATCH] drm/komeda: Potential error pointer dereference
Message-Id: <20190503144114.GF15144@e110455-lin.cambridge.arm.com>
List-Id: <kernel-janitors.vger.kernel.org>
References: <20190503122525.GA29695@mwanda>
In-Reply-To: <20190503122525.GA29695@mwanda>
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To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Airlie <airlied@linux.ie>, kernel-janitors@vger.kernel.org, dri-devel@lists.freedesktop.org, "James (Qian) Wang" <james.qian.wang@arm.com>

On Fri, May 03, 2019 at 03:25:25PM +0300, Dan Carpenter wrote:
> We need to check whether drm_atomic_get_crtc_state() returns an error
> pointer before dereferencing "crtc_st".
> 
> Fixes: 7d31b9e7a550 ("drm/komeda: Add komeda_plane/plane_helper_funcs")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Acked-by: Liviu Dudau <liviu.dudau@arm.com>

I'll pull this and send it as a fix after -rc1.

Best regards,
Liviu

> ---
>  drivers/gpu/drm/arm/display/komeda/komeda_plane.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_plane.c b/drivers/gpu/drm/arm/display/komeda/komeda_plane.c
> index 07ed0cc1bc44..c7e5fc6e5500 100644
> --- a/drivers/gpu/drm/arm/display/komeda/komeda_plane.c
> +++ b/drivers/gpu/drm/arm/display/komeda/komeda_plane.c
> @@ -64,7 +64,7 @@ komeda_plane_atomic_check(struct drm_plane *plane,
>  		return 0;
>  
>  	crtc_st = drm_atomic_get_crtc_state(state->state, state->crtc);
> -	if (!crtc_st->enable) {
> +	if (IS_ERR(crtc_st) || !crtc_st->enable) {
>  		DRM_DEBUG_ATOMIC("Cannot update plane on a disabled CRTC.\n");
>  		return -EINVAL;
>  	}
> -- 
> 2.18.0
> 

-- 
==========
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| but they're not |
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