======================================
| [   17.395600][   T65] ==================================================================
| [ 17.395847][ T65] BUG: KASAN: slab-use-after-free in cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
| [   17.396058][   T65] Read of size 8 at addr ffff8880026d00f8 by task kworker/u16:1/65
| [   17.396262][   T65]
[   17.396540][   T65] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   17.396715][   T65] Workqueue: netns cleanup_net
[   17.396860][   T65] Call Trace:
[   17.396966][   T65]  <TASK>
[ 17.397038][ T65] dump_stack_lvl (lib/dump_stack.c:123)
[ 17.397186][ T65] print_address_description.constprop.0 (mm/kasan/report.c:379)
[ 17.397365][ T65] ? cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 17.397517][ T65] print_report (mm/kasan/report.c:490)
[ 17.397653][ T65] ? kasan_addr_to_slab (./include/linux/mm.h:1294 mm/kasan/../slab.h:211 mm/kasan/common.c:38)
[ 17.397789][ T65] kasan_report (mm/kasan/report.c:604)
[ 17.397896][ T65] ? cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 17.398032][ T65] cleanup_net (net/core/net_namespace.c:462 net/core/net_namespace.c:661)
[ 17.398167][ T65] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 17.398307][ T65] ? __pfx_cleanup_net (net/core/net_namespace.c:592)
[ 17.398442][ T65] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 47))
[ 17.398579][ T65] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 17.398716][ T65] ? process_one_work (kernel/workqueue.c:3205)
[ 17.398856][ T65] process_one_work (kernel/workqueue.c:3229)
[ 17.398998][ T65] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 17.399135][ T65] ? __pfx_process_one_work (kernel/workqueue.c:3131)
[ 17.399272][ T65] ? assign_work (kernel/workqueue.c:1200)
[ 17.399412][ T65] worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
[ 17.399549][ T65] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[ 17.399720][ T65] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 17.399859][ T65] ? __pfx_worker_thread (kernel/workqueue.c:3337)
[ 17.399995][ T65] kthread (kernel/kthread.c:389)
[ 17.400105][ T65] ? __pfx_kthread (kernel/kthread.c:342)
[ 17.400242][ T65] ret_from_fork (arch/x86/kernel/process.c:147)
[ 17.400383][ T65] ? __pfx_kthread (kernel/kthread.c:342)


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