IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready
IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready
IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready
==================================================================
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
BUG: KASAN: use-after-free in _copy_to_user+0x84/0xb0 lib/usercopy.c:27
8021q: adding VLAN 0 to HW filter on device bond0
Read of size 924 at addr ffff88807bfffff3 by task syz-executor.2/6809

IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready
CPU: 0 PID: 6809 Comm: syz-executor.2 Not tainted 4.14.157-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xf7/0x13b lib/dump_stack.c:58
 print_address_description.cold.7+0x9/0x1c9 mm/kasan/report.c:252
IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready
IPv6: ADDRCONF(NETDEV_UP): team0: link is not ready
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report.cold.8+0x11a/0x2d3 mm/kasan/report.c:409
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
 _copy_to_user+0x84/0xb0 lib/usercopy.c:27
 copy_to_user include/linux/uaccess.h:155 [inline]
 bpf_test_finish.isra.5+0xd5/0x170 net/bpf/test_run.c:59
8021q: adding VLAN 0 to HW filter on device team0
IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready
 bpf_prog_test_run_skb+0x66d/0xbc0 net/bpf/test_run.c:144
IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready
IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready
IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready
 bpf_prog_test_run kernel/bpf/syscall.c:1264 [inline]
 SYSC_bpf kernel/bpf/syscall.c:1526 [inline]
 SyS_bpf+0x97e/0x28c3 kernel/bpf/syscall.c:1475
IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready
IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready
 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292
IPv6: ADDRCONF(NETDEV_UP): veth0_to_hsr: link is not ready
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
IPv6: ADDRCONF(NETDEV_UP): veth1_to_hsr: link is not ready
RIP: 0033:0x459829
hsr0: Slave A (hsr_slave_0) is not up; please bring it up to get a fully working HSR network
RSP: 002b:00007f4785727c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000000000028 RSI: 0000000020000140 RDI: 000000000000000a
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f47857286d4
R13: 00000000004bfb92 R14: 00000000004d1758 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea0001efffc0 count:0 mapcount:0 mapping:          (null) index:0x0
hsr0: Slave B (hsr_slave_1) is not up; please bring it up to get a fully working HSR network
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: ffffea0001efffe0 ffffea0001efffe0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88807bfffe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
IPv6: ADDRCONF(NETDEV_UP): hsr0: link is not ready
 ffff88807bffff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88807bffff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                             ^
 ffff88807c000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807c000080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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