KCSAN: data-race in batadv_tt_local_add / batadv_tt_local

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in batadv_tt_local_add / batadv_tt_local_add batman				18	1551d	1630d	0/26	auto-closed as invalid on 2020/04/06 03:45
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BUG: KCSAN: data-race in batadv_tt_local_add / batadv_tt_local_add

write to 0xffff888115e716c0 of 8 bytes by task 19 on cpu 1:
 batadv_tt_local_add+0x156/0x1790 net/batman-adv/translation-table.c:665
 batadv_interface_tx+0x382/0xc30 net/batman-adv/soft-interface.c:248
 __netdev_start_xmit include/linux/netdevice.h:4683 [inline]
 netdev_start_xmit include/linux/netdevice.h:4697 [inline]
 xmit_one+0x105/0x2f0 net/core/dev.c:3473
 dev_hard_start_xmit net/core/dev.c:3489 [inline]
 __dev_queue_xmit+0x86d/0xf90 net/core/dev.c:4116
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4149
 neigh_resolve_output+0x3db/0x410 net/core/neighbour.c:1522
 neigh_output include/net/neighbour.h:541 [inline]
 ip6_finish_output2+0x9ce/0xbe0 net/ipv6/ip6_output.c:126
 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline]
 ip6_finish_output+0x446/0x4c0 net/ipv6/ip6_output.c:201
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:224
 dst_output include/net/dst.h:451 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ndisc_send_skb+0x488/0x610 net/ipv6/ndisc.c:508
 ndisc_send_ns+0x422/0x450 net/ipv6/ndisc.c:650
 addrconf_dad_work+0xafa/0x1170 net/ipv6/addrconf.c:4153
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

write to 0xffff888115e716c0 of 8 bytes by task 1890 on cpu 0:
 batadv_tt_local_add+0x156/0x1790 net/batman-adv/translation-table.c:665
 batadv_interface_tx+0x382/0xc30 net/batman-adv/soft-interface.c:248
 __netdev_start_xmit include/linux/netdevice.h:4683 [inline]
 netdev_start_xmit include/linux/netdevice.h:4697 [inline]
 xmit_one+0x105/0x2f0 net/core/dev.c:3473
 dev_hard_start_xmit net/core/dev.c:3489 [inline]
 __dev_queue_xmit+0x86d/0xf90 net/core/dev.c:4116
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4149
 neigh_hh_output include/net/neighbour.h:525 [inline]
 neigh_output include/net/neighbour.h:539 [inline]
 ip6_finish_output2+0x9a5/0xbe0 net/ipv6/ip6_output.c:126
 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline]
 ip6_finish_output+0x446/0x4c0 net/ipv6/ip6_output.c:201
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:224
 dst_output include/net/dst.h:451 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 mld_sendpack+0x3c7/0x580 net/ipv6/mcast.c:1826
 mld_send_cr net/ipv6/mcast.c:2127 [inline]
 mld_ifc_work+0x586/0x810 net/ipv6/mcast.c:2659
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

value changed: 0x00000001000050b0 -> 0x00000001000050d2

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1890 Comm: kworker/0:3 Not tainted 5.17.0-rc2-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: mld mld_ifc_work
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