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BUG: KASAN: use-after-free in memcpy include/linux/string.h:347 [inline]
BUG: KASAN: use-after-free in batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:717 [inline]
BUG: KASAN: use-after-free in batadv_iv_ogm_queue_add+0x2c2/0xe30 net/batman-adv/bat_iv_ogm.c:813
Read of size 60 at addr ffff88809095cb00 by task kworker/u4:0/5

CPU: 0 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.166-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
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x123/0x190 mm/kasan/kasan.c:267
 memcpy+0x24/0x50 mm/kasan/kasan.c:302
 memcpy include/linux/string.h:347 [inline]
 batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:717 [inline]
 batadv_iv_ogm_queue_add+0x2c2/0xe30 net/batman-adv/bat_iv_ogm.c:813
 batadv_iv_ogm_schedule+0xa61/0xe20 net/batman-adv/bat_iv_ogm.c:982
 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 5:
 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 8876:
 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
 rtnl_delete_link+0xc3/0x110 net/core/rtnetlink.c:2374
 rtnl_dellink+0x206/0x680 net/core/rtnetlink.c:2411
 rtnetlink_rcv_msg+0x3da/0xb70 net/core/rtnetlink.c:4306
 netlink_rcv_skb+0x14f/0x3c0 net/netlink/af_netlink.c:2432
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4318
 netlink_unicast_kernel net/netlink/af_netlink.c:1286 [inline]
 netlink_unicast+0x44d/0x650 net/netlink/af_netlink.c:1312
 netlink_sendmsg+0x7c4/0xc60 net/netlink/af_netlink.c:1877
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 ___sys_sendmsg+0x70a/0x840 net/socket.c:2062
 __sys_sendmsg+0xb9/0x140 net/socket.c:2096
 SYSC_sendmsg net/socket.c:2107 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2103
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff88809095cb00
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes inside of
 64-byte region [ffff88809095cb00, ffff88809095cb40)
The buggy address belongs to the page:
page:ffffea0002425700 count:1 mapcount:0 mapping:ffff88809095c000 index:0x0
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff88809095c000 0000000000000000 0000000100000020
raw: ffffea000231c6e0 ffffea00021cafa0 ffff8880aa800340 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809095ca00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff88809095ca80: 00 00 00 00 00 04 fc fc fc fc fc fc fc fc fc fc
>ffff88809095cb00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                   ^
 ffff88809095cb80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88809095cc00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
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