Commit ef54cf0c authored by Shuah Khan's avatar Shuah Khan Committed by Greg Kroah-Hartman
Browse files

usbip: prevent bind loops on devices attached to vhci_hcd



usbip host binds to devices attached to vhci_hcd on the same server
when user does attach over localhost or specifies the server as the
remote.

usbip attach -r localhost -b busid
or
usbip attach -r servername (or server IP)

Unbind followed by bind works, however device is left in a bad state with
accesses via the attached busid result in errors and system hangs during
shutdown.

Fix it to check and bail out if the device is already attached to vhci_hcd.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f0b4198f
Loading
Loading
Loading
Loading
+9 −0
Original line number Diff line number Diff line
@@ -144,6 +144,7 @@ static int bind_device(char *busid)
	int rc;
	struct udev *udev;
	struct udev_device *dev;
	const char *devpath;

	/* Check whether the device with this bus ID exists. */
	udev = udev_new();
@@ -152,8 +153,16 @@ static int bind_device(char *busid)
		err("device with the specified bus ID does not exist");
		return -1;
	}
	devpath = udev_device_get_devpath(dev);
	udev_unref(udev);

	/* If the device is already attached to vhci_hcd - bail out */
	if (strstr(devpath, USBIP_VHCI_DRV_NAME)) {
		err("bind loop detected: device: %s is attached to %s\n",
		    devpath, USBIP_VHCI_DRV_NAME);
		return -1;
	}

	rc = unbind_other(busid);
	if (rc == UNBIND_ST_FAILED) {
		err("could not unbind driver from device on busid %s", busid);