Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753723AbcDZUag (ORCPT ); Tue, 26 Apr 2016 16:30:36 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:58431 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753823AbcDZU0K (ORCPT ); Tue, 26 Apr 2016 16:26:10 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Alex Deucher , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 50/66] drm/radeon: forbid mapping of userptr bo through radeon device file Date: Tue, 26 Apr 2016 13:24:41 -0700 Message-Id: <1461702297-7792-51-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1461702297-7792-1-git-send-email-kamal@canonical.com> References: <1461702297-7792-1-git-send-email-kamal@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Extended-Stable: 3.19 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1634 Lines: 43 3.19.8-ckt20 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= commit b5dcec693f87cb8475f2291c0075b2422addd3d6 upstream. Allowing userptr bo which are basicly a list of page from some vma (so either anonymous page or file backed page) would lead to serious corruption of kernel structures and counters (because we overwrite the page->mapping field when mapping buffer). This will already block if the buffer was populated before anyone does try to mmap it because then TTM_PAGE_FLAG_SG would be set in in the ttm_tt flags. But that flag is check before ttm_tt_populate in the ttm vm fault handler. So to be safe just add a check to verify_access() callback. Reviewed-by: Christian König Signed-off-by: Jérôme Glisse Signed-off-by: Alex Deucher Signed-off-by: Kamal Mostafa --- drivers/gpu/drm/radeon/radeon_ttm.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c index f5c0590..50ce26a 100644 --- a/drivers/gpu/drm/radeon/radeon_ttm.c +++ b/drivers/gpu/drm/radeon/radeon_ttm.c @@ -235,6 +235,8 @@ static int radeon_verify_access(struct ttm_buffer_object *bo, struct file *filp) { struct radeon_bo *rbo = container_of(bo, struct radeon_bo, tbo); + if (radeon_ttm_tt_has_userptr(bo->ttm)) + return -EPERM; return drm_vma_node_verify_access(&rbo->gem_base.vma_node, filp); } -- 2.7.4