Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

vsock: Do not allow binding to VMADDR_PORT_ANY

It is possible for a vsock to autobind to VMADDR_PORT_ANY. This can cause a use-after-free when a connection is made to the bound socket. The socket returned by accept() also has port VMADDR_PORT_ANY but is not on the list of unbound sockets. Binding it will result in an extra refcount decrement similar to the one fixed in fcdd2242c023 (vsock: Keep the binding until socket destruction).

Modify the check in __vsock_bind_connectible() to also prevent binding to VMADDR_PORT_ANY.