On Mon, Jan 29, 2018 at 01:56:07PM +0100, Greg Kroah-Hartman wrote:
4.4-stable review patch. If anyone has any objections, please let me know.
From: Shuah Khan shuahkh@osg.samsung.com
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 vuln@secunia.com Signed-off-by: Shuah Khan shuahkh@osg.samsung.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
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, 20 insertions(+), 14 deletions(-)
--- a/drivers/usb/usbip/usbip_common.h +++ b/drivers/usb/usbip/usbip_common.h @@ -261,6 +261,7 @@ 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 @@ -39,16 +39,20 @@ static ssize_t status_show(struct device /* * output example:
* prt sta spd dev socket local_busid* 000 004 000 000 c5a7bb80 1-2.3* 001 004 000 000 d8cee980 2-3.4
* port sta spd dev sockfd local_busid* 0000 004 000 00000000 000003 1-2.3* 0001 004 000 00000000 000004 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.
"prt sta spd bus dev socket local_busid\n");
"prt sta spd bus dev sockfd local_busid\n");for (i = 0; i < VHCI_NPORTS; i++) { struct vhci_device *vdev = port_to_vdev(i); @@ -60,11 +64,11 @@ static ssize_t status_show(struct device out += sprintf(out, "%03u %08x ", vdev->speed, vdev->devid); out += sprintf(out, "%16p ", vdev->ud.tcp_socket);
out += sprintf(out, "%06u", vdev->ud.sockfd); out += sprintf(out, "%s", dev_name(&vdev->udev->dev));
This backport is wrong; it's still printing the pointer...
Eric