From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755510AbdKGAVY (ORCPT ); Mon, 6 Nov 2017 19:21:24 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53776 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932761AbdKGAVU (ORCPT ); Mon, 6 Nov 2017 19:21:20 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "David Airlie" , "Chris Wilson" , "Joonas Lahtinen" , "Daniel Vetter" , "Daniel Vetter" , "Ville =?UTF-8?Q?Syrj=C3=A4l=C3=A4?=" , "Thierry Reding" , "Rob Clark" Date: Mon, 06 Nov 2017 23:03:02 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 127/294] drm: Release driver tracking before making the object available again In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Chris Wilson commit fe4600a548f2763dec91b3b27a1245c370ceee2a upstream. This is the same bug as we fixed in commit f6cd7daecff5 ("drm: Release driver references to handle before making it available again"), but now the exposure is via the PRIME lookup tables. If we remove the object/handle from the PRIME lut, then a new request for the same object/fd will generate a new handle, thus for a short window that object is known to userspace by two different handles. Fix this by releasing the driver tracking before PRIME. Fixes: 0ff926c7d4f0 ("drm/prime: add exported buffers to current fprivs imported buffer list (v2)") Signed-off-by: Chris Wilson Cc: David Airlie Cc: Daniel Vetter Cc: Rob Clark Cc: Ville Syrjälä Cc: Thierry Reding Reviewed-by: Daniel Vetter Signed-off-by: Joonas Lahtinen Link: https://patchwork.freedesktop.org/patch/msgid/20170819120558.6465-1-chris@chris-wilson.co.uk [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- drivers/gpu/drm/drm_gem.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -698,13 +698,13 @@ drm_gem_object_release_handle(int id, vo struct drm_gem_object *obj = ptr; struct drm_device *dev = obj->dev; + if (dev->driver->gem_close_object) + dev->driver->gem_close_object(obj, file_priv); + if (drm_core_check_feature(dev, DRIVER_PRIME)) drm_gem_remove_prime_handles(obj, file_priv); drm_vma_node_revoke(&obj->vma_node, file_priv->filp); - if (dev->driver->gem_close_object) - dev->driver->gem_close_object(obj, file_priv); - drm_gem_object_handle_unreference_unlocked(obj); return 0;