syzbot

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BUG: KCSAN: data-race in batadv_hardif_disable_interface.cold / batadv_iv_ogm_schedule_buff

write to 0xffff8880995c5270 of 8 bytes by task 460 on cpu 0:
 batadv_hardif_disable_interface.cold+0x3d8/0x54f net/batman-adv/hard-interface.c:895
 batadv_softif_destroy_netlink+0x83/0xe0 net/batman-adv/soft-interface.c:1113
 default_device_exit_batch+0x1a3/0x270 net/core/dev.c:10375
 ops_exit_list.isra.0+0xa2/0xc0 net/core/net_namespace.c:175
 cleanup_net+0x405/0x6b0 net/core/net_namespace.c:597
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2264
 worker_thread+0xa0/0x800 kernel/workqueue.c:2410
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff8880995c5270 of 8 bytes by task 8259 on cpu 1:
 batadv_iv_ogm_schedule_buff+0x5aa/0x820 net/batman-adv/bat_iv_ogm.c:839
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:865 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:858 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x212/0x510 net/batman-adv/bat_iv_ogm.c:1718
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2264
 worker_thread+0xa0/0x800 kernel/workqueue.c:2410
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8259 Comm: kworker/u4:5 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
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