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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 C68CFC433DF for ; Sat, 8 Aug 2020 20:33:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AAD47206CD for ; Sat, 8 Aug 2020 20:33:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726250AbgHHUd6 (ORCPT ); Sat, 8 Aug 2020 16:33:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726148AbgHHUd5 (ORCPT ); Sat, 8 Aug 2020 16:33:57 -0400 Received: from gofer.mess.org (gofer.mess.org [IPv6:2a02:8011:d000:212::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B78DFC061A27 for ; Sat, 8 Aug 2020 13:33:56 -0700 (PDT) Received: by gofer.mess.org (Postfix, from userid 1000) id 6875BC6373; Sat, 8 Aug 2020 21:33:52 +0100 (BST) From: Sean Young To: linux-media@vger.kernel.org Cc: stable@vger.kernel.org Subject: [PATCH v2 2/2] media: rc: do not access device via sysfs after rc_unregister_device() Date: Sat, 8 Aug 2020 21:33:52 +0100 Message-Id: <20200808203352.9793-2-sean@mess.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200808203352.9793-1-sean@mess.org> References: <20200808203352.9793-1-sean@mess.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Device drivers do not expect to have change_protocol or wakeup re-programming to be accesed after rc_unregister_device(). This can cause the device driver to access deallocated resources. Cc: # 4.16 Signed-off-by: Sean Young --- drivers/media/rc/rc-main.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c index e1cda80a4b25..dee8a9f3d80a 100644 --- a/drivers/media/rc/rc-main.c +++ b/drivers/media/rc/rc-main.c @@ -1292,6 +1292,10 @@ static ssize_t store_protocols(struct device *device, } mutex_lock(&dev->lock); + if (!dev->registered) { + mutex_unlock(&dev->lock); + return -ENODEV; + } old_protocols = *current_protocols; new_protocols = old_protocols; @@ -1430,6 +1434,10 @@ static ssize_t store_filter(struct device *device, return -EINVAL; mutex_lock(&dev->lock); + if (!dev->registered) { + mutex_unlock(&dev->lock); + return -ENODEV; + } new_filter = *filter; if (fattr->mask) @@ -1544,6 +1552,10 @@ static ssize_t store_wakeup_protocols(struct device *device, int i; mutex_lock(&dev->lock); + if (!dev->registered) { + mutex_unlock(&dev->lock); + return -ENODEV; + } allowed = dev->allowed_wakeup_protocols; -- 2.26.2