From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 58489C4360C for ; Thu, 10 Oct 2019 10:44:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 30F8320B7C for ; Thu, 10 Oct 2019 10:44:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570704248; bh=VIbb3aptAylRHg7YIKh9vuIw4H7EIRzm99L7kRT7uTM=; h=Subject:To:From:Date:List-ID:From; b=yz5yS5ydg+UVnJU1yqEOFIiepImWkhP6wSB23TLxvZD0qjbrouUq+h9doI/HWjl72 suZvBfjvXBuaMuuSTn1zcEF/qKbfG121gVYINGVgParEkeiUh3vwe3BePZCN5gdEbN UyBtI94HajtP5MPwF2RelaGiX6QBMI7XWBlmaMHk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726304AbfJJKoH (ORCPT ); Thu, 10 Oct 2019 06:44:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:45622 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725601AbfJJKoH (ORCPT ); Thu, 10 Oct 2019 06:44:07 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CF5CB20B7C; Thu, 10 Oct 2019 10:44:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570704246; bh=VIbb3aptAylRHg7YIKh9vuIw4H7EIRzm99L7kRT7uTM=; h=Subject:To:From:Date:From; b=Ns96KR2rbNfvClJMfqMwhNFxMnyDnrSTuO8wb+zIBsltV7jQk/PX+ZT+2yhX7Dr5V iw8AMDwt6XyWLF+UPtawghDJAiHIEOFDoyGaib3aTvX9//qf2CrieDVodNDb1tyjDj AsjRjqW1DCw1pUgU4XjRcxvy73HZk5mNnOUW+To8= Subject: patch "USB: ldusb: fix NULL-derefs on driver unbind" added to usb-linus To: johan@kernel.org, gregkh@linuxfoundation.org, stable@vger.kernel.org From: Date: Thu, 10 Oct 2019 12:43:53 +0200 Message-ID: <157070423342233@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled USB: ldusb: fix NULL-derefs on driver unbind to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From 58ecf131e74620305175a7aa103f81350bb37570 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 9 Oct 2019 17:38:46 +0200 Subject: USB: ldusb: fix NULL-derefs on driver unbind The driver was using its struct usb_interface pointer as an inverted disconnected flag, but was setting it to NULL before making sure all completion handlers had run. This could lead to a NULL-pointer dereference in a number of dev_dbg, dev_warn and dev_err statements in the completion handlers which relies on said pointer. Fix this by unconditionally stopping all I/O and preventing resubmissions by poisoning the interrupt URBs at disconnect and using a dedicated disconnected flag. This also makes sure that all I/O has completed by the time the disconnect callback returns. Fixes: 2824bd250f0b ("[PATCH] USB: add ldusb driver") Cc: stable # 2.6.13 Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20191009153848.8664-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/misc/ldusb.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/drivers/usb/misc/ldusb.c b/drivers/usb/misc/ldusb.c index 6581774bdfa4..f3108d85e768 100644 --- a/drivers/usb/misc/ldusb.c +++ b/drivers/usb/misc/ldusb.c @@ -153,6 +153,7 @@ MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in struct ld_usb { struct mutex mutex; /* locks this structure */ struct usb_interface *intf; /* save off the usb interface pointer */ + unsigned long disconnected:1; int open_count; /* number of times this port has been opened */ @@ -192,12 +193,10 @@ static void ld_usb_abort_transfers(struct ld_usb *dev) /* shutdown transfer */ if (dev->interrupt_in_running) { dev->interrupt_in_running = 0; - if (dev->intf) - usb_kill_urb(dev->interrupt_in_urb); + usb_kill_urb(dev->interrupt_in_urb); } if (dev->interrupt_out_busy) - if (dev->intf) - usb_kill_urb(dev->interrupt_out_urb); + usb_kill_urb(dev->interrupt_out_urb); } /** @@ -205,8 +204,6 @@ static void ld_usb_abort_transfers(struct ld_usb *dev) */ static void ld_usb_delete(struct ld_usb *dev) { - ld_usb_abort_transfers(dev); - /* free data structures */ usb_free_urb(dev->interrupt_in_urb); usb_free_urb(dev->interrupt_out_urb); @@ -263,7 +260,7 @@ static void ld_usb_interrupt_in_callback(struct urb *urb) resubmit: /* resubmit if we're still running */ - if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) { + if (dev->interrupt_in_running && !dev->buffer_overflow) { retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); if (retval) { dev_err(&dev->intf->dev, @@ -392,7 +389,7 @@ static int ld_usb_release(struct inode *inode, struct file *file) retval = -ENODEV; goto unlock_exit; } - if (dev->intf == NULL) { + if (dev->disconnected) { /* the device was unplugged before the file was released */ mutex_unlock(&dev->mutex); /* unlock here as ld_usb_delete frees dev */ @@ -423,7 +420,7 @@ static __poll_t ld_usb_poll(struct file *file, poll_table *wait) dev = file->private_data; - if (!dev->intf) + if (dev->disconnected) return EPOLLERR | EPOLLHUP; poll_wait(file, &dev->read_wait, wait); @@ -462,7 +459,7 @@ static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count, } /* verify that the device wasn't unplugged */ - if (dev->intf == NULL) { + if (dev->disconnected) { retval = -ENODEV; printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval); goto unlock_exit; @@ -542,7 +539,7 @@ static ssize_t ld_usb_write(struct file *file, const char __user *buffer, } /* verify that the device wasn't unplugged */ - if (dev->intf == NULL) { + if (dev->disconnected) { retval = -ENODEV; printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval); goto unlock_exit; @@ -764,6 +761,9 @@ static void ld_usb_disconnect(struct usb_interface *intf) /* give back our minor */ usb_deregister_dev(intf, &ld_usb_class); + usb_poison_urb(dev->interrupt_in_urb); + usb_poison_urb(dev->interrupt_out_urb); + mutex_lock(&dev->mutex); /* if the device is not opened, then we clean up right now */ @@ -771,7 +771,7 @@ static void ld_usb_disconnect(struct usb_interface *intf) mutex_unlock(&dev->mutex); ld_usb_delete(dev); } else { - dev->intf = NULL; + dev->disconnected = 1; /* wake up pollers */ wake_up_interruptible_all(&dev->read_wait); wake_up_interruptible_all(&dev->write_wait); -- 2.23.0