Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759650AbdLRQ51 (ORCPT ); Mon, 18 Dec 2017 11:57:27 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:42222 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759805AbdLRQLG (ORCPT ); Mon, 18 Dec 2017 11:11:06 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Secunia Research , Shuah Khan Subject: [PATCH 4.14 019/178] usbip: prevent vhci_hcd driver from leaking a socket pointer address Date: Mon, 18 Dec 2017 16:47:35 +0100 Message-Id: <20171218152921.357944840@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171218152920.567991776@linuxfoundation.org> References: <20171218152920.567991776@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4481 Lines: 129 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shuah Khan commit 2f2d0088eb93db5c649d2a5e34a3800a8a935fc5 upstream. When a client has a USB device attached over IP, the vhci_hcd driver is locally leaking a socket pointer address via the /sys/devices/platform/vhci_hcd/status file (world-readable) and in debug output when "usbip --debug port" is run. Fix it to not leak. The socket pointer address is not used at the moment and it was made visible as a convenient way to find IP address from socket pointer address by looking up /proc/net/{tcp,tcp6}. As this opens a security hole, the fix replaces socket pointer address with sockfd. Reported-by: Secunia Research Signed-off-by: Shuah Khan Signed-off-by: Greg Kroah-Hartman --- drivers/usb/usbip/usbip_common.h | 1 + drivers/usb/usbip/vhci_sysfs.c | 25 ++++++++++++++++--------- tools/usb/usbip/libsrc/vhci_driver.c | 8 ++++---- 3 files changed, 21 insertions(+), 13 deletions(-) --- a/drivers/usb/usbip/usbip_common.h +++ b/drivers/usb/usbip/usbip_common.h @@ -270,6 +270,7 @@ struct usbip_device { /* lock for status */ spinlock_t lock; + int sockfd; struct socket *tcp_socket; struct task_struct *tcp_rx; --- a/drivers/usb/usbip/vhci_sysfs.c +++ b/drivers/usb/usbip/vhci_sysfs.c @@ -31,15 +31,20 @@ /* * output example: - * hub port sta spd dev socket local_busid - * hs 0000 004 000 00000000 c5a7bb80 1-2.3 + * hub port sta spd dev sockfd local_busid + * hs 0000 004 000 00000000 3 1-2.3 * ................................................ - * ss 0008 004 000 00000000 d8cee980 2-3.4 + * ss 0008 004 000 00000000 4 2-3.4 * ................................................ * - * IP address can be retrieved from a socket pointer address by looking - * up /proc/net/{tcp,tcp6}. Also, a userland program may remember a - * port number and its peer IP address. + * Output includes socket fd instead of socket pointer address to avoid + * leaking kernel memory address in: + * /sys/devices/platform/vhci_hcd.0/status and in debug output. + * The socket pointer address is not used at the moment and it was made + * visible as a convenient way to find IP address from socket pointer + * address by looking up /proc/net/{tcp,tcp6}. As this opens a security + * hole, the change is made to use sockfd instead. + * */ static void port_show_vhci(char **out, int hub, int port, struct vhci_device *vdev) { @@ -53,8 +58,8 @@ static void port_show_vhci(char **out, i if (vdev->ud.status == VDEV_ST_USED) { *out += sprintf(*out, "%03u %08x ", vdev->speed, vdev->devid); - *out += sprintf(*out, "%16p %s", - vdev->ud.tcp_socket, + *out += sprintf(*out, "%u %s", + vdev->ud.sockfd, dev_name(&vdev->udev->dev)); } else { @@ -174,7 +179,8 @@ static ssize_t nports_show(struct device char *s = out; /* - * Half the ports are for SPEED_HIGH and half for SPEED_SUPER, thus the * 2. + * Half the ports are for SPEED_HIGH and half for SPEED_SUPER, + * thus the * 2. */ out += sprintf(out, "%d\n", VHCI_PORTS * vhci_num_controllers); return out - s; @@ -380,6 +386,7 @@ static ssize_t store_attach(struct devic vdev->devid = devid; vdev->speed = speed; + vdev->ud.sockfd = sockfd; vdev->ud.tcp_socket = socket; vdev->ud.status = VDEV_ST_NOTASSIGNED; --- a/tools/usb/usbip/libsrc/vhci_driver.c +++ b/tools/usb/usbip/libsrc/vhci_driver.c @@ -50,14 +50,14 @@ static int parse_status(const char *valu while (*c != '\0') { int port, status, speed, devid; - unsigned long socket; + int sockfd; char lbusid[SYSFS_BUS_ID_SIZE]; struct usbip_imported_device *idev; char hub[3]; - ret = sscanf(c, "%2s %d %d %d %x %lx %31s\n", + ret = sscanf(c, "%2s %d %d %d %x %u %31s\n", hub, &port, &status, &speed, - &devid, &socket, lbusid); + &devid, &sockfd, lbusid); if (ret < 5) { dbg("sscanf failed: %d", ret); @@ -66,7 +66,7 @@ static int parse_status(const char *valu dbg("hub %s port %d status %d speed %d devid %x", hub, port, status, speed, devid); - dbg("socket %lx lbusid %s", socket, lbusid); + dbg("sockfd %u lbusid %s", sockfd, lbusid); /* if a device is connected, look at it */ idev = &vhci_driver->idev[port];