On 01/24/2018 04:37 AM, Michal Privoznik wrote:

When starting an LXC container, the /dev entries are created under temp root (/var/run/libvirt/lxc/$name.dev), relabelled and then the root is pivoted. However, when it comes to USB devices which keep path to the device in the structure we need a way to override the default /dev/usb/... path because we want to work with the one under temp root. That's what @vroot argument is for in virUSBDeviceNew. However, what is being passed there is:

vroot = /var/run/libvirt/lxc/lxc_0.dev/bus/usb

Therefore, constructed path is wrong:

dev->path = //var/run/libvirt/lxc/lxc_0.dev/bus/usb//dev/bus/usb/002/002

Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/util/virusb.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)

Reviewed-by: John Ferlan <jferlan@redhat.com>

diff --git a/src/util/virusb.c b/src/util/virusb.c index 6359235ff..f06639eec 100644 --- a/src/util/virusb.c +++ b/src/util/virusb.c @@ -343,9 +343,13 @@ virUSBDeviceNew(unsigned int bus, virUSBDeviceFree(dev); return NULL; } - if (virAsprintf(&dev->path, "%s" USB_DEVFS "%03d/%03d", - vroot ? vroot : "", - dev->bus, dev->dev) < 0) { + + if ((vroot && + virAsprintf(&dev->path, "%s/%03d/%03d", + vroot, dev->bus, dev->dev) < 0) || + (!vroot && + virAsprintf(&dev->path, USB_DEVFS "%03d/%03d", + dev->bus, dev->dev) < 0)) {

This I think is of those cases where something like: if (vroot) rc = virAsprintf() else rc = virAsprintf() if (rc < 0) just is easier to read. Your call - the code works, just causes personal eye irritation ;-) John

virUSBDeviceFree(dev); return NULL; }