Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752965AbdDKDcU (ORCPT ); Mon, 10 Apr 2017 23:32:20 -0400 Received: from regular1.263xmail.com ([211.150.99.132]:36979 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752497AbdDKDcT (ORCPT ); Mon, 10 Apr 2017 23:32:19 -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: <6eda789f6e85a8b2d747c49388c32a03> 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, marcheu@chromium.org, mark.yao@rock-chips.com, hshi@chromium.org, Jeffy Chen , Daniel Vetter , Jani Nikula , dri-devel@lists.freedesktop.org, David Airlie Subject: [PATCH v7 2/2] drm: Prevent release fb after cleanup drm_mode_config Date: Tue, 11 Apr 2017 11:31:42 +0800 Message-Id: <1491881502-24357-3-git-send-email-jeffy.chen@rock-chips.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1491881502-24357-1-git-send-email-jeffy.chen@rock-chips.com> References: <1491881502-24357-1-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: 1073 Lines: 42 We are freeing all framebuffers in drm_mode_config_cleanup without sync the drm_file's fbs list. So if someone try to unbind drm before release drm dev fd, the fbs list would remain some invalid fb references. And that would cause crash later in drm_fb_release. Add a sanity check to prevent that. Signed-off-by: Jeffy Chen --- Changes in v7: Update commit message. Changes in v6: None Changes in v5: None Changes in v2: None drivers/gpu/drm/drm_framebuffer.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c index e8f9c13..03c1632 100644 --- a/drivers/gpu/drm/drm_framebuffer.c +++ b/drivers/gpu/drm/drm_framebuffer.c @@ -583,6 +583,11 @@ void drm_fb_release(struct drm_file *priv) { struct drm_framebuffer *fb, *tfb; struct drm_mode_rmfb_work arg; + struct drm_minor *minor = priv->minor; + struct drm_device *dev = minor->dev; + + if (WARN_ON(!dev->mode_config.num_fb && !list_empty(&priv->fbs))) + return; INIT_LIST_HEAD(&arg.fbs); -- 2.1.4