From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Masney Subject: [PATCH RFC 1/6] drm/msm: fix null pointer dereference in msm_atomic_prepare_fb() Date: Sun, 5 May 2019 09:04:08 -0400 Message-ID: <20190505130413.32253-2-masneyb@onstation.org> References: <20190505130413.32253-1-masneyb@onstation.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190505130413.32253-1-masneyb@onstation.org> Sender: linux-kernel-owner@vger.kernel.org To: robdclark@gmail.com, sean@poorly.run, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, airlied@linux.ie, daniel@ffwll.ch, linux-kernel@vger.kernel.org, linus.walleij@linaro.org List-Id: linux-arm-msm@vger.kernel.org _msm_gem_new() calls msm_gem_new_impl() with a NULL reservation_object struct. msm_atomic_prepare_fb() assumes that the reservation_object is always set, and attempts to reference a NULL pointer. Correct this by checking to see if this value is NULL. Signed-off-by: Brian Masney --- drivers/gpu/drm/msm/msm_atomic.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/msm/msm_atomic.c b/drivers/gpu/drm/msm/msm_atomic.c index f5b1256e32b6..0da80a93876a 100644 --- a/drivers/gpu/drm/msm/msm_atomic.c +++ b/drivers/gpu/drm/msm/msm_atomic.c @@ -56,10 +56,12 @@ int msm_atomic_prepare_fb(struct drm_plane *plane, return 0; obj = msm_framebuffer_bo(new_state->fb, 0); - msm_obj = to_msm_bo(obj); - fence = reservation_object_get_excl_rcu(msm_obj->resv); - drm_atomic_set_fence_for_plane(new_state, fence); + msm_obj = to_msm_bo(obj); + if (msm_obj->resv) { + fence = reservation_object_get_excl_rcu(msm_obj->resv); + drm_atomic_set_fence_for_plane(new_state, fence); + } return msm_framebuffer_prepare(new_state->fb, kms->aspace); } -- 2.20.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 443DDC004C9 for ; Sun, 5 May 2019 13:05:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0D24E20B7C for ; Sun, 5 May 2019 13:05:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=onstation.org header.i=@onstation.org header.b="cisTXGYJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727601AbfEENE2 (ORCPT ); Sun, 5 May 2019 09:04:28 -0400 Received: from onstation.org ([52.200.56.107]:46266 "EHLO onstation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727367AbfEENE1 (ORCPT ); Sun, 5 May 2019 09:04:27 -0400 Received: from localhost.localdomain (c-98-239-145-235.hsd1.wv.comcast.net [98.239.145.235]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: masneyb) by onstation.org (Postfix) with ESMTPSA id E6AC33E956; Sun, 5 May 2019 13:04:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=onstation.org; s=default; t=1557061467; bh=IYRglZLmPUAWG3JXhJg/NhCUwxXVo+rWDdjly3A1S/Q=; h=From:To:Subject:Date:In-Reply-To:References:From; b=cisTXGYJKhqlZDiZ7H58vZ3MF5wT2phT/dMC/JzrjrWxB4vZ9keVlfpNH8QbDKxLu 0H8OCuZYuSLBVybeIjy4Oj2edU6EY5o0g+6tuOcVtfAUaBd25YBQXVTTnBVPWZ27gP yX6QQc899NidHFHpeH2R+dGs7TFpodOVtUNJb6Xw= From: Brian Masney To: robdclark@gmail.com, sean@poorly.run, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, airlied@linux.ie, daniel@ffwll.ch, linux-kernel@vger.kernel.org, linus.walleij@linaro.org Subject: [PATCH RFC 1/6] drm/msm: fix null pointer dereference in msm_atomic_prepare_fb() Date: Sun, 5 May 2019 09:04:08 -0400 Message-Id: <20190505130413.32253-2-masneyb@onstation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190505130413.32253-1-masneyb@onstation.org> References: <20190505130413.32253-1-masneyb@onstation.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Message-ID: <20190505130408.pAnj82XNToD_J51NZ1QWFCHrliLnMQgHt_udHKDSzEM@z> _msm_gem_new() calls msm_gem_new_impl() with a NULL reservation_object struct. msm_atomic_prepare_fb() assumes that the reservation_object is always set, and attempts to reference a NULL pointer. Correct this by checking to see if this value is NULL. Signed-off-by: Brian Masney --- drivers/gpu/drm/msm/msm_atomic.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/msm/msm_atomic.c b/drivers/gpu/drm/msm/msm_atomic.c index f5b1256e32b6..0da80a93876a 100644 --- a/drivers/gpu/drm/msm/msm_atomic.c +++ b/drivers/gpu/drm/msm/msm_atomic.c @@ -56,10 +56,12 @@ int msm_atomic_prepare_fb(struct drm_plane *plane, return 0; obj = msm_framebuffer_bo(new_state->fb, 0); - msm_obj = to_msm_bo(obj); - fence = reservation_object_get_excl_rcu(msm_obj->resv); - drm_atomic_set_fence_for_plane(new_state, fence); + msm_obj = to_msm_bo(obj); + if (msm_obj->resv) { + fence = reservation_object_get_excl_rcu(msm_obj->resv); + drm_atomic_set_fence_for_plane(new_state, fence); + } return msm_framebuffer_prepare(new_state->fb, kms->aspace); } -- 2.20.1