======================================
| xx__-> [   17.237809][   T64] ==================================================================
| [ 17.238121][ T64] BUG: KASAN: slab-use-after-free in cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
| [   17.238398][   T64] Read of size 8 at addr ffff8880087780f8 by task kworker/u16:1/64
| [   17.238621][   T64]
[   17.238934][   T64] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   17.239134][   T64] Workqueue: netns cleanup_net
[   17.239304][   T64] Call Trace:
[   17.239427][   T64]  <TASK>
[ 17.239513][ T64] dump_stack_lvl (lib/dump_stack.c:123)
[ 17.239680][ T64] print_address_description.constprop.0 (mm/kasan/report.c:379)
[ 17.239880][ T64] ? cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 17.240036][ T64] print_report (mm/kasan/report.c:490)
[ 17.240225][ T64] ? kasan_addr_to_slab (./include/linux/mm.h:1294 mm/kasan/../slab.h:211 mm/kasan/common.c:38)
[ 17.240386][ T64] kasan_report (mm/kasan/report.c:604)
[ 17.240516][ T64] ? cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 17.240697][ T64] cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 17.240869][ T64] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 17.241046][ T64] ? __pfx_cleanup_net (net/core/net_namespace.c:592)
[ 17.241212][ T64] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 47))
[ 17.241432][ T64] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 17.241602][ T64] ? process_one_work (kernel/workqueue.c:3205)
[ 17.241775][ T64] process_one_work (kernel/workqueue.c:3229)
[ 17.241947][ T64] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 17.242122][ T64] ? __pfx_process_one_work (kernel/workqueue.c:3131)
[ 17.242291][ T64] ? assign_work (kernel/workqueue.c:1200)
[ 17.242460][ T64] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[ 17.242625][ T64] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[ 17.242835][ T64] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 17.243004][ T64] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 17.243172][ T64] kthread (kernel/kthread.c:389)
[ 17.243304][ T64] ? __pfx_kthread (kernel/kthread.c:342)
[ 17.243489][ T64] ret_from_fork (arch/x86/kernel/process.c:147)
[ 17.243662][ T64] ? __pfx_kthread (kernel/kthread.c:342)


Finger prints:
print_report:kasan_report:cleanup_net:process_one_work:worker_thread