From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755282AbdBGNFM (ORCPT ); Tue, 7 Feb 2017 08:05:12 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:36864 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755152AbdBGNCi (ORCPT ); Tue, 7 Feb 2017 08:02:38 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Rui Miguel Silva , Viresh Kumar , Johan Hovold Subject: [PATCH 4.9 56/66] staging: greybus: timesync: validate platform state callback Date: Tue, 7 Feb 2017 13:59:30 +0100 Message-Id: <20170207124530.818651270@linuxfoundation.org> X-Mailer: git-send-email 2.11.1 In-Reply-To: <20170207124528.281881183@linuxfoundation.org> References: <20170207124528.281881183@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rui Miguel Silva commit b17c1bba9cec1727451b906d9a0c209774624873 upstream. When tearingdown timesync, and not in arche platform, the state platform callback is not initialized. That will trigger the following NULL dereferencing. CallTrace: ? gb_timesync_platform_unlock_bus+0x11/0x20 [greybus] gb_timesync_teardown+0x85/0xc0 [greybus] gb_timesync_svc_remove+0xab/0x190 [greybus] gb_svc_del+0x29/0x110 [greybus] gb_hd_del+0x14/0x20 [greybus] ap_disconnect+0x24/0x60 [gb_es2] usb_unbind_interface+0x7a/0x2c0 __device_release_driver+0x96/0x150 device_release_driver+0x1e/0x30 bus_remove_device+0xe7/0x130 device_del+0x116/0x230 usb_disable_device+0x97/0x1f0 usb_disconnect+0x80/0x260 hub_event+0x5ca/0x10e0 process_one_work+0x126/0x3b0 worker_thread+0x55/0x4c0 ? process_one_work+0x3b0/0x3b0 kthread+0xc4/0xe0 ? kthread_park+0xb0/0xb0 ret_from_fork+0x22/0x30 So, fix that by adding checks before use the callback. Fixes: 970dc85bd95d ("greybus: timesync: Add timesync core driver") Signed-off-by: Rui Miguel Silva Reviewed-by: Viresh Kumar Reviewed-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/staging/greybus/timesync_platform.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/staging/greybus/timesync_platform.c +++ b/drivers/staging/greybus/timesync_platform.c @@ -45,12 +45,18 @@ u32 gb_timesync_platform_get_clock_rate( int gb_timesync_platform_lock_bus(struct gb_timesync_svc *pdata) { + if (!arche_platform_change_state_cb) + return 0; + return arche_platform_change_state_cb(ARCHE_PLATFORM_STATE_TIME_SYNC, pdata); } void gb_timesync_platform_unlock_bus(void) { + if (!arche_platform_change_state_cb) + return; + arche_platform_change_state_cb(ARCHE_PLATFORM_STATE_ACTIVE, NULL); }