======================================
| [   19.563374][   T11] ==================================================================
| [ 19.563617][ T11] BUG: KASAN: slab-use-after-free in cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
| [   19.563830][   T11] Read of size 8 at addr ffff888004f800f8 by task kworker/u16:0/11
| [   19.564044][   T11]
[   19.564337][   T11] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   19.564516][   T11] Workqueue: netns cleanup_net
[   19.564669][   T11] Call Trace:
[   19.564778][   T11]  <TASK>
[ 19.564853][ T11] dump_stack_lvl (lib/dump_stack.c:123)
[ 19.565004][ T11] print_address_description.constprop.0 (mm/kasan/report.c:379)
[ 19.565192][ T11] ? cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 19.565335][ T11] print_report (mm/kasan/report.c:490)
[ 19.565473][ T11] ? kasan_addr_to_slab (./include/linux/mm.h:1294 mm/kasan/../slab.h:211 mm/kasan/common.c:38)
[ 19.565630][ T11] kasan_report (mm/kasan/report.c:604)
[ 19.565743][ T11] ? cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 19.565884][ T11] cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 19.566023][ T11] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 19.566168][ T11] ? __pfx_cleanup_net (net/core/net_namespace.c:592)
[ 19.566314][ T11] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 47))
[ 19.566453][ T11] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 19.566592][ T11] ? process_one_work (kernel/workqueue.c:3205)
[ 19.566734][ T11] process_one_work (kernel/workqueue.c:3229)
[ 19.566874][ T11] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 19.567012][ T11] ? __pfx_process_one_work (kernel/workqueue.c:3131)
[ 19.567153][ T11] ? assign_work (kernel/workqueue.c:1200)
[ 19.567308][ T11] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[ 19.567463][ T11] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 19.567602][ T11] kthread (kernel/kthread.c:389)
[ 19.567709][ T11] ? __pfx_kthread (kernel/kthread.c:342)
[ 19.567851][ T11] ret_from_fork (arch/x86/kernel/process.c:147)
[ 19.567992][ T11] ? __pfx_kthread (kernel/kthread.c:342)


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