In the Linux kernel, the following vulnerability has been resolved:
tcp: Fix Use-After-Free in tcpaoconnect_init
Since callrcu, which is called in the hlistforeachentryrcu traversal of tcpaoconnectinit, is not part of the RCU read critical section, it is possible that the RCU grace period will pass during the traversal and the key will be free.
To prevent this, it should be changed to hlistforeachentrysafe.