======================================
| xx__-> [ 1144.170509][   T12] ==================================================================
| [ 1144.170759][   T12] BUG: KASAN: slab-use-after-free in idr_for_each (./include/linux/radix-tree.h:424 lib/idr.c:204)
| [ 1144.170922][   T12] Read of size 8 at addr ff11000012a16a70 by task kworker/u16:0/12
| [ 1144.171079][   T12]
[ 1144.171137][   T12] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1144.171139][   T12] Workqueue: netns cleanup_net
[ 1144.171145][   T12] Call Trace:
[ 1144.171147][   T12]  <TASK>
[ 1144.171149][   T12]  dump_stack_lvl (lib/dump_stack.c:122)
[ 1144.171154][   T12]  print_address_description.constprop.0 (mm/kasan/report.c:379)
[ 1144.171159][   T12]  print_report (mm/kasan/report.c:483)
[ 1144.171161][   T12]  ? idr_for_each (./include/linux/radix-tree.h:424 lib/idr.c:204)
[ 1144.171163][   T12]  ? __virt_addr_valid (./include/linux/rcupdate.h:981 (discriminator 3) ./include/linux/mmzone.h:2194 (discriminator 3) arch/x86/mm/physaddr.c:54 (discriminator 3))
[ 1144.171167][   T12]  ? idr_for_each (./include/linux/radix-tree.h:424 lib/idr.c:204)
[ 1144.171168][   T12]  kasan_report (mm/kasan/report.c:597)
[ 1144.171172][   T12]  ? idr_for_each (./include/linux/radix-tree.h:424 lib/idr.c:204)
[ 1144.171174][   T12]  ? rtnl_net_notifyid (net/core/net_namespace.c:628)
[ 1144.171176][   T12]  idr_for_each (./include/linux/radix-tree.h:424 lib/idr.c:204)
[ 1144.171178][   T12]  ? idr_find (lib/idr.c:199)
[ 1144.171180][   T12]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5536)
[ 1144.171184][   T12]  ? __up_write (kernel/locking/rwsem.c:1388 (discriminator 3))
[ 1144.171185][   T12]  ? cleanup_net (net/core/net_namespace.c:656 net/core/net_namespace.c:700)
[ 1144.171187][   T12]  cleanup_net (net/core/net_namespace.c:658 net/core/net_namespace.c:700)
[ 1144.171188][   T12]  ? lock_acquire.part.0 (kernel/locking/lockdep.c:470 kernel/locking/lockdep.c:5870)
[ 1144.171190][   T12]  ? process_one_work (kernel/workqueue.c:3233 (discriminator 1))
[ 1144.171193][   T12]  ? net_passive_dec (net/core/net_namespace.c:668)
[ 1144.171194][   T12]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 1) kernel/rcu/tree.c:751 (discriminator 1))
[ 1144.171197][   T12]  ? process_one_work (kernel/workqueue.c:3233 (discriminator 1))
[ 1144.171198][   T12]  ? lock_acquire (./include/trace/events/lock.h:24 (discriminator 33) kernel/locking/lockdep.c:5831 (discriminator 33))
[ 1144.171199][   T12]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 1) kernel/rcu/tree.c:751 (discriminator 1))
[ 1144.171201][   T12]  process_one_work (kernel/workqueue.c:3262)
[ 1144.171204][   T12]  ? pwq_dec_nr_in_flight (kernel/workqueue.c:3159)
[ 1144.171205][   T12]  ? lock_acquire.part.0 (kernel/locking/lockdep.c:470 kernel/locking/lockdep.c:5870)
[ 1144.171208][   T12]  ? assign_work (kernel/workqueue.c:1200)
[ 1144.171209][   T12]  worker_thread (kernel/workqueue.c:3334 (discriminator 2) kernel/workqueue.c:3421 (discriminator 2))
[ 1144.171212][   T12]  ? process_one_work (kernel/workqueue.c:3367)
[ 1144.171213][   T12]  kthread (kernel/kthread.c:463)
[ 1144.171215][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)
[ 1144.171217][   T12]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5536)
[ 1144.171219][   T12]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 1) kernel/rcu/tree.c:751 (discriminator 1))
[ 1144.171220][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)
[ 1144.171221][   T12]  ret_from_fork (arch/x86/kernel/process.c:164)
[ 1144.171225][   T12]  ? arch_exit_to_user_mode_prepare.isra.0 (arch/x86/entry/syscall_64.c:37)
[ 1144.171228][   T12]  ? __switch_to (./arch/x86/include/asm/cpufeature.h:101 arch/x86/kernel/process_64.c:377 arch/x86/kernel/process_64.c:665)
[ 1144.171230][   T12]  ? kthread_is_per_cpu (kernel/kthread.c:412)


Finger prints:
print_report:kasan_report:idr_for_each:cleanup_net:process_one_work