IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
A link change request failed with some changes committed already. Interface caif0 may have been left with an inconsistent configuration, please check.
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
==================================================================
BUG: KASAN: use-after-free in batadv_iv_ogm_schedule+0xdc4/0xe20 net/batman-adv/bat_iv_ogm.c:951
Write of size 2 at addr ffff88805be2af16 by task kworker/u4:1/22

CPU: 1 PID: 22 Comm: kworker/u4:1 Not tainted 4.14.167-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
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x142/0x197 lib/dump_stack.c:58
 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393
 __asan_report_store2_noabort+0x17/0x20 mm/kasan/report.c:433
 batadv_iv_ogm_schedule+0xdc4/0xe20 net/batman-adv/bat_iv_ogm.c:951
 batadv_iv_send_outstanding_bat_ogm_packet+0x4a1/0x680 net/batman-adv/bat_iv_ogm.c:1809
 process_one_work+0x863/0x1600 kernel/workqueue.c:2114
 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Allocated by task 22:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x45/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc mm/kasan/kasan.c:551 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529
 __do_kmalloc mm/slab.c:3720 [inline]
 __kmalloc+0x15d/0x7a0 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 batadv_tvlv_realloc_packet_buff net/batman-adv/tvlv.c:288 [inline]
 batadv_tvlv_container_ogm_append+0x12b/0x480 net/batman-adv/tvlv.c:329
 batadv_iv_ogm_schedule+0xba0/0xe20 net/batman-adv/bat_iv_ogm.c:945
 batadv_iv_send_outstanding_bat_ogm_packet+0x4a1/0x680 net/batman-adv/bat_iv_ogm.c:1809
 process_one_work+0x863/0x1600 kernel/workqueue.c:2114
 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Freed by task 269:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x45/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kfree+0xcc/0x270 mm/slab.c:3815
 batadv_iv_ogm_iface_disable+0x39/0x80 net/batman-adv/bat_iv_ogm.c:393
 batadv_hardif_disable_interface.cold+0x605/0x840 net/batman-adv/hard-interface.c:836
 batadv_softif_destroy_netlink+0xad/0x140 net/batman-adv/soft-interface.c:1134
 default_device_exit_batch+0x22c/0x3d0 net/core/dev.c:8724
 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:145
 cleanup_net+0x3ba/0x870 net/core/net_namespace.c:484
 process_one_work+0x863/0x1600 kernel/workqueue.c:2114
 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

The buggy address belongs to the object at ffff88805be2af00
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 22 bytes inside of
 192-byte region [ffff88805be2af00, ffff88805be2afc0)
The buggy address belongs to the page:
page:ffffea00016f8a80 count:1 mapcount:0 mapping:ffff88805be2a000 index:0x0
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff88805be2a000 0000000000000000 0000000100000010
raw: ffffea0002655260 ffffea0001c66660 ffff8880aa800040 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88805be2ae00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805be2ae80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88805be2af00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88805be2af80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88805be2b000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================