From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org ([198.145.29.96]:42188 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751657AbdJXQQl (ORCPT ); Tue, 24 Oct 2017 12:16:41 -0400 From: Jack Pham To: Greg KH Cc: mrana@codeaurora.org, mathias.nyman@linux.intel.com, stable@vger.kernel.org, Jack Pham Subject: [PATCH] usb: xhci: Handle error condition in xhci_stop_device() Date: Tue, 24 Oct 2017 09:16:19 -0700 Message-Id: <20171024161619.3536-1-jackp@codeaurora.org> In-Reply-To: <20171024102237.GA7323@kroah.com> References: <20171024102237.GA7323@kroah.com> Sender: stable-owner@vger.kernel.org List-ID: From: Mayank Rana commit b3207c65dfafae27e7c492cb9188c0dc0eeaf3fd upstream. xhci_stop_device() calls xhci_queue_stop_endpoint() multiple times without checking the return value. xhci_queue_stop_endpoint() can return error if the HC is already halted or unable to queue commands. This can cause a deadlock condition as xhci_stop_device() would end up waiting indefinitely for a completion for the command that didn't get queued. Fix this by checking the return value and bailing out of xhci_stop_device() in case of error. This patch happens to fix potential memory leaks of the allocated command structures as well. Fixes: c311e391a7ef ("xhci: rework command timeout and cancellation,") Signed-off-by: Mayank Rana Signed-off-by: Jack Pham Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- Hi Greg, I tested that this applies cleanly to 3.18.y, 4.4.y and 4.9.y. Thanks, jack drivers/usb/host/xhci-hub.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 4a02c5c..0722f75 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -412,15 +412,25 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend) GFP_NOWAIT); if (!command) { spin_unlock_irqrestore(&xhci->lock, flags); - xhci_free_command(xhci, cmd); - return -ENOMEM; + ret = -ENOMEM; + goto cmd_cleanup; + } + ret = xhci_queue_stop_endpoint(xhci, command, slot_id, + i, suspend); + if (ret) { + spin_unlock_irqrestore(&xhci->lock, flags); + xhci_free_command(xhci, command); + goto cmd_cleanup; } - xhci_queue_stop_endpoint(xhci, command, slot_id, i, - suspend); } } - xhci_queue_stop_endpoint(xhci, cmd, slot_id, 0, suspend); + ret = xhci_queue_stop_endpoint(xhci, cmd, slot_id, 0, suspend); + if (ret) { + spin_unlock_irqrestore(&xhci->lock, flags); + goto cmd_cleanup; + } + xhci_ring_cmd_db(xhci); spin_unlock_irqrestore(&xhci->lock, flags); @@ -431,6 +441,8 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend) xhci_warn(xhci, "Timeout while waiting for stop endpoint command\n"); ret = -ETIME; } + +cmd_cleanup: xhci_free_command(xhci, cmd); return ret; } -- 2.9.1.200.gb1ec08f