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Message-ID: <602351ea7a1addf1b1349536fa8d23435d2862ad.camel@redhat.com>
Subject: Re: [PATCH] nouveau_connector: add nv_encoder pointer check for NULL
From:   Lyude Paul <lyude@redhat.com>
To:     Natalia Petrova <n.petrova@fintech.ru>,
        Ben Skeggs <bskeggs@redhat.com>
Cc:     Karol Herbst <kherbst@redhat.com>, David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org
Date:   Tue, 13 Jun 2023 16:52:25 -0400
In-Reply-To: <20230512103320.82234-1-n.petrova@fintech.ru>
References: <20230512103320.82234-1-n.petrova@fintech.ru>
Organization: Red Hat Inc.
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Nice catch!

Reviewed-by: Lyude Paul <lyude@redhat.com>

Will push upstream

On Fri, 2023-05-12 at 13:33 +0300, Natalia Petrova wrote:
> Pointer nv_encoder could be dereferenced at nouveau_connector.c
> in case it's equal to NULL by jumping to goto label.
> This patch adds a NULL-check to avoid it.
>=20
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>=20
> Fixes: 3195c5f9784a ("drm/nouveau: set encoder for lvds")
> Signed-off-by: Natalia Petrova <n.petrova@fintech.ru>
> ---
>  drivers/gpu/drm/nouveau/nouveau_connector.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>=20
> diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/dr=
m/nouveau/nouveau_connector.c
> index 43a9d1e1cf71..90ba6d0a9c80 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_connector.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
> @@ -729,7 +729,8 @@ nouveau_connector_detect_lvds(struct drm_connector *c=
onnector, bool force)
>  #endif
> =20
>  	nouveau_connector_set_edid(nv_connector, edid);
> -	nouveau_connector_set_encoder(connector, nv_encoder);
> +	if (nv_encoder)
> +		nouveau_connector_set_encoder(connector, nv_encoder);
>  	return status;
>  }
> =20

--=20
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat