From: Johan Hovold Date: Tue, 13 Sep 2022 08:53:11 +0000 (+0200) Subject: drm/msm: fix use-after-free on probe deferral X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=6808abdb33bf90330e70a687d29f038507e06ebb;p=linux.git drm/msm: fix use-after-free on probe deferral The bridge counter was never reset when tearing down the DRM device so that stale pointers to deallocated structures would be accessed on the next tear down (e.g. after a second late bind deferral). Given enough bridges and a few probe deferrals this could currently also lead to data beyond the bridge array being corrupted. Fixes: d28ea556267c ("drm/msm: properly add and remove internal bridges") Fixes: a3376e3ec81c ("drm/msm: convert to drm_bridge") Cc: stable@vger.kernel.org # 3.12 Reviewed-by: Dmitry Baryshkov Signed-off-by: Johan Hovold Tested-by: Kuogee Hsieh Reviewed-by: Kuogee Hsieh Patchwork: https://patchwork.freedesktop.org/patch/502665/ Link: https://lore.kernel.org/r/20220913085320.8577-2-johan+linaro@kernel.org Signed-off-by: Abhinav Kumar --- diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c index 07f66412533b9..fec6d449eded5 100644 --- a/drivers/gpu/drm/msm/msm_drv.c +++ b/drivers/gpu/drm/msm/msm_drv.c @@ -247,6 +247,7 @@ static int msm_drm_uninit(struct device *dev) for (i = 0; i < priv->num_bridges; i++) drm_bridge_remove(priv->bridges[i]); + priv->num_bridges = 0; pm_runtime_get_sync(dev); msm_irq_uninstall(ddev);