From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f171.google.com ([209.85.192.171]:35665 "EHLO mail-pf0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750703AbdAXDSE (ORCPT ); Mon, 23 Jan 2017 22:18:04 -0500 Received: by mail-pf0-f171.google.com with SMTP id f144so46287815pfa.2 for ; Mon, 23 Jan 2017 19:18:04 -0800 (PST) Date: Tue, 24 Jan 2017 08:47:59 +0530 From: Viresh Kumar To: Rui Miguel Silva Cc: Greg Kroah-Hartman , Bryan O'Donoghue , devel@driverdev.osuosl.org, Johan Hovold , "# 4 . 9 . x" , greybus-dev@lists.linaro.org, Alex Elder Subject: Re: [greybus-dev] [PATCH v2] staging: greybus: timesync: validate platform state callback Message-ID: <20170124031759.GD26681@vireshk-i7> References: <20170123163257.15855-1-rmfrfs@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170123163257.15855-1-rmfrfs@gmail.com> Sender: stable-owner@vger.kernel.org List-ID: On 23-01-17, 16:32, Rui Miguel Silva wrote: > 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") > Cc: # 4.9.x > Signed-off-by: Rui Miguel Silva > --- > Greg, > This patch does not contain the "commit upstream" snippet since you > already removed the timesync code from the -next tree, even though it is still > in 4.10-rc. However this will affect the greybus users of 4.9.x. If you > meanwhile pull that remove to rc, this patch is only necessary in stable 4.9.x. > > v1->v2: > - add Fixes tag to changelog > Johan Hovold: > - for symmetry with the lock, adjust the unlock_bus function accordantly. Reviewed-by: Viresh Kumar -- viresh