In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: fix ref leak when switching zones When switching zones or network namespaces without doing a ct clear in between, it is now leaking a reference to the old ct entry. That's because tcf_ct_skb_nfct_cached() returns false and tcf_ct_flow_table_lookup() may simply overwrite it. The fix is to, as the ct entry is not reusable, free it already at tcf_ct_skb_nfct_cached().
https://git.kernel.org/stable/c/bcbf4e5c3b5b373cd61528392dd1ec8e9c0fd33d
https://git.kernel.org/stable/c/bcb74e132a76ce0502bb33d5b65533a4ed72d159
https://git.kernel.org/stable/c/b24793a37d91aacad7cb9893b226a7924a89636a
https://git.kernel.org/stable/c/4bb42d73def9411e5cad885b9811987d72431df1