Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932359AbdDEIbs (ORCPT ); Wed, 5 Apr 2017 04:31:48 -0400 Received: from regular1.263xmail.com ([211.150.99.138]:50539 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932227AbdDEIbr (ORCPT ); Wed, 5 Apr 2017 04:31:47 -0400 X-263anti-spam: KSV:0; X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-RL-SENDER: jeffy.chen@rock-chips.com X-FST-TO: linux-kernel@vger.kernel.org X-SENDER-IP: 103.29.142.67 X-LOGIN-NAME: jeffy.chen@rock-chips.com X-UNIQUE-TAG: X-ATTACHMENT-NUM: 0 X-DNS-TYPE: 0 From: Jeffy Chen To: linux-kernel@vger.kernel.org Cc: briannorris@chromium.org, dianders@chromium.org, tfiga@chromium.org, seanpaul@chromium.org, zyw@rock-chips.com, mark.yao@rock-chips.com, Jeffy Chen , Heiko Stuebner , dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, David Airlie , linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 8/9] drm/rockchip: gem: Don't alloc/free gem buf when dev_private is invalid Date: Wed, 5 Apr 2017 16:29:26 +0800 Message-Id: <1491380967-28570-9-git-send-email-jeffy.chen@rock-chips.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1491380967-28570-1-git-send-email-jeffy.chen@rock-chips.com> References: <1491380967-28570-1-git-send-email-jeffy.chen@rock-chips.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1287 Lines: 47 After unbinding drm, the userspace may still has a chance to access gem buf. Add a sanity check for a NULL dev_private to prevent that from happening. Signed-off-by: Jeffy Chen --- Changes in v3: Address Daniel Vetter 's comments. Update commit message. Changes in v2: None drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index df9e570..205a3dc 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -184,6 +184,9 @@ static int rockchip_gem_alloc_buf(struct rockchip_gem_object *rk_obj, struct drm_device *drm = obj->dev; struct rockchip_drm_private *private = drm->dev_private; + if (!private) + return -ENODEV; + if (private->domain) return rockchip_gem_alloc_iommu(rk_obj, alloc_kmap); else @@ -208,6 +211,11 @@ static void rockchip_gem_free_dma(struct rockchip_gem_object *rk_obj) static void rockchip_gem_free_buf(struct rockchip_gem_object *rk_obj) { + struct drm_device *drm = rk_obj->base.dev; + + if (!drm->dev_private) + return; + if (rk_obj->pages) rockchip_gem_free_iommu(rk_obj); else -- 2.1.4