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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 0242DC4360F for ; Mon, 1 Apr 2019 17:17:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C4BA420856 for ; Mon, 1 Apr 2019 17:17:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554139052; bh=RSboMfHQ+qEjwa1+a/GyWSyG0GmvuI9fLVSGvbR+Tzs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xepYXZxCCgyEr/5DWXAFBRpLpnWlggRtc122xu6Eg3CvyX/LCrCJHqp+rZMCnhSrd hbmfu1cbWCQANAycz+iwwbQ3ScZ8mPZu/FApGYsEOvyx94rQjUS2fvXhyi1ySXJn2v DtRQRG/uzeZOUpR6zgVR6WY2pPlnJru/28IbIwRM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730448AbfDARRb (ORCPT ); Mon, 1 Apr 2019 13:17:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:43652 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730560AbfDARR2 (ORCPT ); Mon, 1 Apr 2019 13:17:28 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C468720856; Mon, 1 Apr 2019 17:17:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554139048; bh=RSboMfHQ+qEjwa1+a/GyWSyG0GmvuI9fLVSGvbR+Tzs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U456mb/tPcVFWvlgzmTYTrWdqmV5O56n8mUM9ycvxutcjMzcIWacVyS3kXWM6SoPj YzmCHKNyBrIKGbBN0p7VqmfAxB3Hz6d6ba1EZdoYzOBrQywetuoGPQrVF2m9vQ0N2+ oICehKI9HEvq7en96iv0/926hg+MSjxTBsotgsEQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+e73f2fb5ed5a5df36d33@syzkaller.appspotmail.com, Chris Wilson , Laura Abbott , Daniel Vetter , Eric Biggers , Rodrigo Siqueira , Maxime Ripard Subject: [PATCH 4.19 097/134] drm/vgem: fix use-after-free when drm_gem_handle_create() fails Date: Mon, 1 Apr 2019 19:02:13 +0200 Message-Id: <20190401170053.340382505@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190401170044.243719205@linuxfoundation.org> References: <20190401170044.243719205@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Biggers commit 21d2b122732318b48c10b7262e15595ce54511d3 upstream. If drm_gem_handle_create() fails in vgem_gem_create(), then the drm_vgem_gem_object is freed twice: once when the reference is dropped by drm_gem_object_put_unlocked(), and again by __vgem_gem_destroy(). This was hit by syzkaller using fault injection. Fix it by skipping the second free. Reported-by: syzbot+e73f2fb5ed5a5df36d33@syzkaller.appspotmail.com Fixes: af33a9190d02 ("drm/vgem: Enable dmabuf import interfaces") Reviewed-by: Chris Wilson Cc: Laura Abbott Cc: Daniel Vetter Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Acked-by: Laura Abbott Signed-off-by: Rodrigo Siqueira Link: https://patchwork.freedesktop.org/patch/msgid/20190226214451.195123-1-ebiggers@kernel.org Signed-off-by: Maxime Ripard Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/vgem/vgem_drv.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -191,13 +191,9 @@ static struct drm_gem_object *vgem_gem_c ret = drm_gem_handle_create(file, &obj->base, handle); drm_gem_object_put_unlocked(&obj->base); if (ret) - goto err; + return ERR_PTR(ret); return &obj->base; - -err: - __vgem_gem_destroy(obj); - return ERR_PTR(ret); } static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev,