In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: Fix race between namespace cleanup and gc in the list:set type
Lion Ackermann reported that there is a race condition between namespace cleanup in ipset and the garbage collection of the list:set type. The namespace cleanup can destroy the list:set type of sets while the gc of the set type is waiting to run in rcu cleanup. The latter uses data from the destroyed set which thus leads use after free. The patch contains the following parts:
The patch depends on c1193d9bbbd3 (netfilter: ipset: Add list flush to cancel_gc).