CVE-2021-47024 Information

Description

In the Linux kernel the following vulnerability has been resolved:

vsock/virtio: free queued packets when closing socket

As reported by syzbot [1] there is a memory leak while closing the socket. We partially solved this issue with commit ac03046ece2b (sock/virtio: free packets during the socket release) but we forgot to drain the RX queue when the socket is definitely closed by the scheduled work.

To avoid future issues let’s use the new virtio_transport_remove_sock() to drain the RX queue before removing the socket from the af_vsock lists calling vsock_remove_sock().

[1] https://syzkaller.appspot.com/bug?extid=24452624fc4c571eedd9

Reference

https://git.kernel.org/stable/c/b605673b523fe33abeafb2136759bcbc9c1e6ebf https://git.kernel.org/stable/c/27691665145e74a45034a9dccf1150cf1894763a https://git.kernel.org/stable/c/37c38674ef2f8d7e8629e5d433c37d6c1273d16b https://git.kernel.org/stable/c/8432b8114957235f42e070a16118a7f750de9d39