Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966009AbcCPIIJ (ORCPT ); Wed, 16 Mar 2016 04:08:09 -0400 Received: from mail.kernel.org ([198.145.29.136]:59229 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965945AbcCPIH7 (ORCPT ); Wed, 16 Mar 2016 04:07:59 -0400 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Zhao Junwang , Daniel Vetter , Zefan Li Subject: [PATCH 3.4 017/107] drm: add a check for x/y in drm_mode_setcrtc Date: Wed, 16 Mar 2016 16:05:11 +0800 Message-Id: <1458115601-5762-17-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1458115541-5712-1-git-send-email-lizf@kernel.org> References: <1458115541-5712-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1407 Lines: 45 From: Zhao Junwang 3.4.111-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit 01447e9f04ba1c49a9534ae6a5a6f26c2bb05226 upstream. legacy setcrtc ioctl does take a 32 bit value which might indeed overflow the checks of crtc_req->x > INT_MAX and crtc_req->y > INT_MAX aren't needed any more with this v2: -polish the annotation according to Daniel's comment Cc: Daniel Vetter Signed-off-by: Zhao Junwang Signed-off-by: Daniel Vetter Signed-off-by: Zefan Li --- drivers/gpu/drm/drm_crtc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index c61e672..ed4b748 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1836,8 +1836,11 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data, if (!drm_core_check_feature(dev, DRIVER_MODESET)) return -EINVAL; - /* For some reason crtc x/y offsets are signed internally. */ - if (crtc_req->x > INT_MAX || crtc_req->y > INT_MAX) + /* + * Universal plane src offsets are only 16.16, prevent havoc for + * drivers using universal plane code internally. + */ + if (crtc_req->x & 0xffff0000 || crtc_req->y & 0xffff0000) return -ERANGE; mutex_lock(&dev->mode_config.mutex); -- 1.9.1