From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753524AbdCFJS4 (ORCPT ); Mon, 6 Mar 2017 04:18:56 -0500 Received: from mx2.suse.de ([195.135.220.15]:37193 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753108AbdCFJO2 (ORCPT ); Mon, 6 Mar 2017 04:14:28 -0500 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Alexey Khoroshilov , Greg Kroah-Hartman , Jiri Slaby Subject: [PATCH 3.12 111/113] USB: cdc-acm: fix double usb_autopm_put_interface() in acm_port_activate() Date: Mon, 6 Mar 2017 10:12:15 +0100 Message-Id: X-Mailer: git-send-email 2.12.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alexey Khoroshilov 3.12-stable review patch. If anyone has any objections, please let me know. =============== 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: Jiri Slaby --- 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 c78c4f7efb40..545413b76c18 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -517,13 +517,16 @@ 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); @@ -550,7 +553,6 @@ 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); -- 2.12.0