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Message-ID: <4119ed8c7ace96e1fa46b34fd9e8404828c3e57d.camel@redhat.com>
Subject: Re: [PATCH RESEND] drm: i915: fix a possible refcount leak in
 intel_dp_add_mst_connector()
From:   Lyude Paul <lyude@redhat.com>
To:     Hangyu Hua <hbh25y@gmail.com>, jani.nikula@linux.intel.com,
        joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com,
        tvrtko.ursulin@linux.intel.com, airlied@linux.ie, daniel@ffwll.ch,
        ville.syrjala@linux.intel.com, jose.souza@intel.com,
        matthew.d.roper@intel.com, anshuman.gupta@intel.com,
        heying24@huawei.com, james.ausmus@intel.com
Cc:     intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org
Date:   Tue, 28 Jun 2022 18:55:57 -0400
In-Reply-To: <20220624022813.10796-1-hbh25y@gmail.com>
References: <20220624022813.10796-1-hbh25y@gmail.com>
Organization: Red Hat Inc.
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Nice catch!

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

Will push to drm-intel-next

On Fri, 2022-06-24 at 10:28 +0800, Hangyu Hua wrote:
> If drm_connector_init fails, intel_connector_free will be called to take
> care of proper free. So it is necessary to drop the refcount of port
> before intel_connector_free.
> 
> Fixes: 091a4f91942a ("drm/i915: Handle drm-layer errors in
> intel_dp_add_mst_connector")
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
> Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp_mst.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 061b277e5ce7..14d2a64193b2 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -839,6 +839,7 @@ static struct drm_connector
> *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
>         ret = drm_connector_init(dev, connector,
> &intel_dp_mst_connector_funcs,
>                                  DRM_MODE_CONNECTOR_DisplayPort);
>         if (ret) {
> +               drm_dp_mst_put_port_malloc(port);
>                 intel_connector_free(intel_connector);
>                 return NULL;
>         }

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