From patchwork Fri Dec 12 15:57:38 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Imre Deak X-Patchwork-Id: 5483601 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 3F610BEEA8 for ; Fri, 12 Dec 2014 15:57:44 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7158E2014A for ; Fri, 12 Dec 2014 15:57:43 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 55A1420148 for ; Fri, 12 Dec 2014 15:57:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E61116E992; Fri, 12 Dec 2014 07:57:41 -0800 (PST) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id BEE896E992 for ; Fri, 12 Dec 2014 07:57:40 -0800 (PST) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP; 12 Dec 2014 07:57:40 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.07,564,1413270000"; d="scan'208";a="622819315" Received: from intelbox.fi.intel.com (HELO localhost) ([10.237.72.105]) by orsmga001.jf.intel.com with ESMTP; 12 Dec 2014 07:57:39 -0800 From: Imre Deak To: intel-gfx@lists.freedesktop.org Date: Fri, 12 Dec 2014 17:57:38 +0200 Message-Id: <1418399858-26849-1-git-send-email-imre.deak@intel.com> X-Mailer: git-send-email 1.8.4 Subject: [Intel-gfx] [PATCH] drm/i915: fix use after free during eDP encoder destroying X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP After commit a18c0af171bfb875012da26f23df051004726973 uthor: Thierry Reding Date: Wed Dec 10 11:38:49 2014 +0100 drm: Zero out DRM object memory upon cleanup we will use the eDP encoder during destroying it. Fix this by calling drm_encoder_cleanup() at a point when the encoder is not used any more. This caused a NULL pointer dereference in pps_lock(), I can't see that it caused any other problem. All the other encoders seem to call drm_encoder_cleanup() at a safe place. Signed-off-by: Imre Deak Reviewed-by: Ville Syrjälä Tested-By: PRC QA PRTS (Patch Regression Test System Contact: shuang.he@intel.com) Reviewed-by: Thierry Reding --- drivers/gpu/drm/i915/intel_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 3fc3296..0a55623 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -4310,7 +4310,6 @@ void intel_dp_encoder_destroy(struct drm_encoder *encoder) drm_dp_aux_unregister(&intel_dp->aux); intel_dp_mst_encoder_cleanup(intel_dig_port); - drm_encoder_cleanup(encoder); if (is_edp(intel_dp)) { cancel_delayed_work_sync(&intel_dp->panel_vdd_work); /* @@ -4326,6 +4325,7 @@ void intel_dp_encoder_destroy(struct drm_encoder *encoder) intel_dp->edp_notifier.notifier_call = NULL; } } + drm_encoder_cleanup(encoder); kfree(intel_dig_port); }