From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:58680 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387739AbeIXSkI (ORCPT ); Mon, 24 Sep 2018 14:40:08 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jia-Ju Bai Subject: [PATCH 4.18 132/235] usb: cdc-wdm: Fix a sleep-in-atomic-context bug in service_outstanding_interrupt() Date: Mon, 24 Sep 2018 13:51:58 +0200 Message-Id: <20180924113119.060092870@linuxfoundation.org> In-Reply-To: <20180924113103.999624566@linuxfoundation.org> References: <20180924113103.999624566@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: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jia-Ju Bai commit 6e22e3af7bb3a7b9dc53cb4687659f6e63fca427 upstream. wdm_in_callback() is a completion handler function for the USB driver. So it should not sleep. But it calls service_outstanding_interrupt(), which calls usb_submit_urb() with GFP_KERNEL. To fix this bug, GFP_KERNEL is replaced with GFP_ATOMIC. This bug is found by my static analysis tool DSAC. Signed-off-by: Jia-Ju Bai Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-wdm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -458,7 +458,7 @@ static int service_outstanding_interrupt set_bit(WDM_RESPONDING, &desc->flags); spin_unlock_irq(&desc->iuspin); - rv = usb_submit_urb(desc->response, GFP_KERNEL); + rv = usb_submit_urb(desc->response, GFP_ATOMIC); spin_lock_irq(&desc->iuspin); if (rv) { dev_err(&desc->intf->dev,