From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Peter Chen , Jack Pham , Mathias Nyman Subject: [PATCH 4.19 009/110] xhci: handle port status events for removed USB3 hcd Date: Thu, 29 Nov 2018 15:11:40 +0100 Message-Id: <20181129135921.619729335@linuxfoundation.org> In-Reply-To: <20181129135921.231283053@linuxfoundation.org> References: <20181129135921.231283053@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Nyman commit 1245374e9b8340fc255fd51b2015173a83050d03 upstream. At xhci removal the USB3 hcd (shared_hcd) is removed before the primary USB2 hcd. Interrupts for port status changes may still occur for USB3 ports after the shared_hcd is freed, causing NULL pointer dereference. Check if xhci->shared_hcd is still valid before handing USB3 port events Cc: Reported-by: Peter Chen Tested-by: Jack Pham Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-ring.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1552,6 +1552,13 @@ static void handle_port_status(struct xh goto cleanup; } + /* We might get interrupts after shared_hcd is removed */ + if (port->rhub == &xhci->usb3_rhub && xhci->shared_hcd == NULL) { + xhci_dbg(xhci, "ignore port event for removed USB3 hcd\n"); + bogus_port_status = true; + goto cleanup; + } + hcd = port->rhub->hcd; bus_state = &xhci->bus_state[hcd_index(hcd)]; hcd_portnum = port->hcd_portnum;