usbnet: Prevents free active kevent

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: usbnet: Prevents free active kevent The root cause of this issue are: 1. When probing the usbnet device, executing usbnet_link_change(dev, 0, 0); put the kevent work in global workqueue. However, the kevent has not yet been scheduled when the usbnet device is unregistered. Therefore, executing free_netdev() results in the "free active object (kevent)" error reported here. 2. Another factor is that when calling usbnet_disconnect()->unregister_netdev(), if the usbnet device is up, ndo_stop() is executed to cancel the kevent. However, because the device is not up, ndo_stop() is not executed. The solution to this problem is to cancel the kevent before executing free_netdev().

References

• https://git.kernel.org/stable/c/285d4b953f2ca03c358f986718dd89ee9bde632e
• https://git.kernel.org/stable/c/88a38b135d69f5db9024ff6527232f1b51be8915
• https://git.kernel.org/stable/c/43005002b60ef3424719ecda16d124714b45da3b
• https://git.kernel.org/stable/c/3a10619fdefd3051aeb14860e4d4335529b4e94d
• https://git.kernel.org/stable/c/9a579d6a39513069d298eee70770bbac8a148565
• https://git.kernel.org/stable/c/2ce1de32e05445d77fc056f6ff8339cfb78a5f84
• https://git.kernel.org/stable/c/5158fb8da162e3982940f30cd01ed77bdf42c6fc
• https://git.kernel.org/stable/c/420c84c330d1688b8c764479e5738bbdbf0a33de