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BUG: KMSAN: uninit-value in __hlist_del include/linux/list.h:812 [inline]
BUG: KMSAN: uninit-value in detach_timer kernel/time/timer.c:814 [inline]
BUG: KMSAN: uninit-value in expire_timers kernel/time/timer.c:1438 [inline]
BUG: KMSAN: uninit-value in __run_timers+0xbd9/0x11c0 kernel/time/timer.c:1773
CPU: 0 PID: 1211 Comm: kworker/u4:15 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1df/0x240 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 __hlist_del include/linux/list.h:812 [inline]
 detach_timer kernel/time/timer.c:814 [inline]
 expire_timers kernel/time/timer.c:1438 [inline]
 __run_timers+0xbd9/0x11c0 kernel/time/timer.c:1773
 run_timer_softirq+0x2d/0x50 kernel/time/timer.c:1786
 __do_softirq+0x311/0x83d kernel/softirq.c:293
 asm_call_on_stack+0x12/0x20 arch/x86/entry/entry_64.S:711
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:23 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 do_softirq_own_stack+0x7c/0xa0 arch/x86/kernel/irq_64.c:77
 do_softirq kernel/softirq.c:338 [inline]
 __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:190
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 get_next_corpse net/netfilter/nf_conntrack_core.c:2238 [inline]
 nf_ct_iterate_cleanup+0x5b6/0x710 net/netfilter/nf_conntrack_core.c:2261
 nf_ct_iterate_cleanup_net+0x182/0x230 net/netfilter/nf_conntrack_core.c:2346
 masq_device_event+0x10c/0x180 net/netfilter/nf_nat_masquerade.c:88
 notifier_call_chain kernel/notifier.c:83 [inline]
 __raw_notifier_call_chain kernel/notifier.c:361 [inline]
 raw_notifier_call_chain+0x130/0x250 kernel/notifier.c:368
 call_netdevice_notifiers_info net/core/dev.c:2027 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
 call_netdevice_notifiers net/core/dev.c:2053 [inline]
 dev_close_many+0x673/0xaf0 net/core/dev.c:1628
 rollback_registered_many+0x8ae/0x25e0 net/core/dev.c:8945
 unregister_netdevice_many net/core/dev.c:10113 [inline]
 default_device_exit_batch+0x73b/0xc60 net/core/dev.c:10596
 ops_exit_list net/core/net_namespace.c:189 [inline]
 cleanup_net+0xf37/0x1a70 net/core/net_namespace.c:603
 process_one_work+0x1540/0x1f30 kernel/workqueue.c:2269
 worker_thread+0xed2/0x23f0 kernel/workqueue.c:2415
 kthread+0x515/0x550 kernel/kthread.c:292
 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:293

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:144
 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:269 [inline]
 kmsan_alloc_page+0xb9/0x180 mm/kmsan/kmsan_shadow.c:293
 __alloc_pages_nodemask+0x56a2/0x5dc0 mm/page_alloc.c:4889
 __alloc_pages include/linux/gfp.h:509 [inline]
 __alloc_pages_node include/linux/gfp.h:522 [inline]
 alloc_pages_node include/linux/gfp.h:536 [inline]
 __page_frag_cache_refill mm/page_alloc.c:4964 [inline]
 page_frag_alloc+0x3ae/0x910 mm/page_alloc.c:4994
 __netdev_alloc_skb+0x703/0xbb0 net/core/skbuff.c:456
 __netdev_alloc_skb_ip_align include/linux/skbuff.h:2826 [inline]
 netdev_alloc_skb_ip_align include/linux/skbuff.h:2836 [inline]
 batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:558 [inline]
 batadv_iv_ogm_queue_add+0x10da/0x1900 net/batman-adv/bat_iv_ogm.c:670
 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:833 [inline]
 batadv_iv_ogm_schedule+0xd63/0x1430 net/batman-adv/bat_iv_ogm.c:869
 batadv_iv_send_outstanding_bat_ogm_packet+0xbae/0xd50 net/batman-adv/bat_iv_ogm.c:1722
 process_one_work+0x1540/0x1f30 kernel/workqueue.c:2269
 worker_thread+0xed2/0x23f0 kernel/workqueue.c:2415
 kthread+0x515/0x550 kernel/kthread.c:292
 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:293
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