From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:33830 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730396AbeJQBPP (ORCPT ); Tue, 16 Oct 2018 21:15:15 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yu Zhao , "David S. Miller" Subject: [PATCH 4.9 33/71] net/usb: cancel pending work when unbinding smsc75xx Date: Tue, 16 Oct 2018 19:09:30 +0200 Message-Id: <20181016170541.053284987@linuxfoundation.org> In-Reply-To: <20181016170539.315587743@linuxfoundation.org> References: <20181016170539.315587743@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yu Zhao [ Upstream commit f7b2a56e1f3dcbdb4cf09b2b63e859ffe0e09df8 ] Cancel pending work before freeing smsc75xx private data structure during binding. This fixes the following crash in the driver: BUG: unable to handle kernel NULL pointer dereference at 0000000000000050 IP: mutex_lock+0x2b/0x3f Workqueue: events smsc75xx_deferred_multicast_write [smsc75xx] task: ffff8caa83e85700 task.stack: ffff948b80518000 RIP: 0010:mutex_lock+0x2b/0x3f Call Trace: smsc75xx_deferred_multicast_write+0x40/0x1af [smsc75xx] process_one_work+0x18d/0x2fc worker_thread+0x1a2/0x269 ? pr_cont_work+0x58/0x58 kthread+0xfa/0x10a ? pr_cont_work+0x58/0x58 ? rcu_read_unlock_sched_notrace+0x48/0x48 ret_from_fork+0x22/0x40 Signed-off-by: Yu Zhao Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/usb/smsc75xx.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/net/usb/smsc75xx.c +++ b/drivers/net/usb/smsc75xx.c @@ -1518,6 +1518,7 @@ static void smsc75xx_unbind(struct usbne { struct smsc75xx_priv *pdata = (struct smsc75xx_priv *)(dev->data[0]); if (pdata) { + cancel_work_sync(&pdata->set_multicast); netif_dbg(dev, ifdown, dev->net, "free pdata\n"); kfree(pdata); pdata = NULL;