======================================
| xx__-> [   20.426454][   T11] ==================================================================
| [ 20.426690][ T11] BUG: KASAN: slab-use-after-free in cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
| [   20.426907][   T11] Read of size 8 at addr ffff8880056a00f8 by task kworker/u16:0/11
| [   20.427108][   T11]
[   20.427381][   T11] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   20.427556][   T11] Workqueue: netns cleanup_net
[   20.427706][   T11] Call Trace:
[   20.427809][   T11]  <TASK>
[ 20.427883][ T11] dump_stack_lvl (lib/dump_stack.c:123)
[ 20.428026][ T11] print_address_description.constprop.0 (mm/kasan/report.c:379)
[ 20.428200][ T11] ? cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 20.428341][ T11] print_report (mm/kasan/report.c:490)
[ 20.428478][ T11] ? kasan_addr_to_slab (./include/linux/mm.h:1294 mm/kasan/../slab.h:211 mm/kasan/common.c:38)
[ 20.428615][ T11] kasan_report (mm/kasan/report.c:604)
[ 20.428720][ T11] ? cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 20.428858][ T11] cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 20.428993][ T11] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 20.429134][ T11] ? __pfx_cleanup_net (net/core/net_namespace.c:592)
[ 20.429279][ T11] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 47))
[ 20.429417][ T11] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 20.429555][ T11] ? process_one_work (kernel/workqueue.c:3205)
[ 20.429696][ T11] process_one_work (kernel/workqueue.c:3229)
[ 20.429837][ T11] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 20.429975][ T11] ? __pfx_process_one_work (kernel/workqueue.c:3131)
[ 20.430113][ T11] ? assign_work (kernel/workqueue.c:1200)
[ 20.430250][ T11] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[ 20.430392][ T11] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 20.430527][ T11] kthread (kernel/kthread.c:389)
[ 20.430631][ T11] ? __pfx_kthread (kernel/kthread.c:342)
[ 20.430769][ T11] ret_from_fork (arch/x86/kernel/process.c:147)
[ 20.430906][ T11] ? __pfx_kthread (kernel/kthread.c:342)


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