安装Oracle VM VirtualBox Extension Pack，需要把linux用户加入

命令：sudo usermod -aG vboxusers

重启系统或者注销用户生效

资料来源： http://askubuntu.com/questions/25596/how-to-set-up-usb-for-virtualbox

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sudo adduser 你的linux用户名 vboxusers

然后重新启动

资料来源：

Ok, that's my solution, simplified and improved with the help of vorburger and boechat.

Short answer:

Execute sudo adduser YOURUSERNAME vboxusers, log out and log in again.

Long Answer:

Close virtualbox

Execute in bash: sudo adduser YOURUSERNAME vboxusers

Log out and log in again

Attach to your PC the USB devices you want to be automatically mounted in the VM (virtual machine).

Open Virtualbox

Select your VM and go to "Machine" -> "Settings" -> "USB".

Check "Enable USB Controller"; click on the icon with the USB plug and the plus, and click on the devices you want to be automatically mounted in the VM. Click "Ok".

Click on "Start" toolbar button, and ensure your USB devices are recognized and mounted by the VM. Remember that you have to unmount them in the host OS too if you have to disconnect them after you exit the VM.

Note that Extensions Pack and Guest Additions are not strictly required, but with Extension Pack you can use USB 2.0. You have also to enable it under USB settings. Without it all your USB devices are controlled as USB 1.0, so they will work at lower speed.