Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752895AbdFSSfO (ORCPT + 2 others); Mon, 19 Jun 2017 14:35:14 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:51964 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752814AbdFSSfH (ORCPT ); Mon, 19 Jun 2017 14:35:07 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Alexey Khoroshilov , Greg Kroah-Hartman , Willy Tarreau Subject: [PATCH 3.10 051/268] USB: cdc-acm: fix double usb_autopm_put_interface() in acm_port_activate() Date: Mon, 19 Jun 2017 20:29:10 +0200 Message-Id: <1497897167-14556-52-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1497897167-14556-1-git-send-email-w@1wt.eu> References: <1497897167-14556-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: From: Alexey Khoroshilov commit 070c0b17f6a1ba39dff9be112218127e7e8fd456 upstream. If acm_submit_read_urbs() fails in acm_port_activate(), error handling code calls usb_autopm_put_interface() while it is already called before acm_submit_read_urbs(). The patch reorganizes error handling code to avoid double decrement of USB interface's PM-usage counter. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov Acked-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman Signed-off-by: Willy Tarreau --- drivers/usb/class/cdc-acm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index b364845..e16b9ef 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -546,13 +546,16 @@ static int acm_port_activate(struct tty_port *port, struct tty_struct *tty) if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) { dev_err(&acm->control->dev, "%s - usb_submit_urb(ctrl irq) failed\n", __func__); + usb_autopm_put_interface(acm->control); goto error_submit_urb; } acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS; if (acm_set_control(acm, acm->ctrlout) < 0 && - (acm->ctrl_caps & USB_CDC_CAP_LINE)) + (acm->ctrl_caps & USB_CDC_CAP_LINE)) { + usb_autopm_put_interface(acm->control); goto error_set_control; + } usb_autopm_put_interface(acm->control); @@ -579,7 +582,6 @@ error_submit_read_urbs: error_set_control: usb_kill_urb(acm->ctrlurb); error_submit_urb: - usb_autopm_put_interface(acm->control); error_get_interface: disconnected: mutex_unlock(&acm->mutex); -- 2.8.0.rc2.1.gbe9624a