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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=no 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 E066AC43331 for ; Mon, 11 Nov 2019 12:03:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7FE421872 for ; Mon, 11 Nov 2019 12:03:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727001AbfKKMD2 (ORCPT ); Mon, 11 Nov 2019 07:03:28 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:34698 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726810AbfKKMD2 (ORCPT ); Mon, 11 Nov 2019 07:03:28 -0500 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: ezequiel) with ESMTPSA id B665228F3C1 Message-ID: <9c46d5a708814082cc0c8a94e53e9e21a12271f1.camel@collabora.com> Subject: Re: [PATCH v2] media: rockchip/rga: fix potential use after free From: Ezequiel Garcia To: Pan Bian , Jacob Chen , Mauro Carvalho Chehab , Heiko Stuebner Cc: linux-media@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org Date: Mon, 11 Nov 2019 09:03:17 -0300 In-Reply-To: <1573460902-18563-1-git-send-email-bianpan2016@163.com> References: <1573460902-18563-1-git-send-email-bianpan2016@163.com> Organization: Collabora Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.1-2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Pan Bian, Thanks for the patch. On Mon, 2019-11-11 at 16:28 +0800, Pan Bian wrote: > The variable vga->vfd is an alias for vfd. Therefore, releasing vfd and > then unregister vga->vfd will lead to a use after free bug. In fact, the > free operation and the unregister operation are reversed. > Out of curiosity, how did you find this potential bug? Acked-by: Ezequiel Garcia Regards, Ezequiel