WARNING in hsr_addr_subst_dest

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    195303136f19 Merge tag 'kconfig-v4.21-2' of git://git.kern..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14fcd2e7400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5e7dc790609552d7
dashboard link: https://syzkaller.appspot.com/bug?extid=b92e4f1472a54e1c7dec
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=107db700c00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12304827400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+b92e4f1472a54e1c7dec@xxxxxxxxxxxxxxxxxxxxxxxxx

IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
------------[ cut here ]------------
hsr_addr_subst_dest: Unknown node
WARNING: CPU: 1 PID: 7814 at net/hsr/hsr_framereg.c:301  
hsr_addr_subst_dest+0x6c7/0x850 net/hsr/hsr_framereg.c:301
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 7814 Comm: syz-executor962 Not tainted 4.20.0+ #396
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d3/0x2c6 lib/dump_stack.c:113
 panic+0x2ad/0x55f kernel/panic.c:189
 __warn.cold.8+0x20/0x52 kernel/panic.c:544
 report_bug+0x254/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:hsr_addr_subst_dest+0x6c7/0x850 net/hsr/hsr_framereg.c:301
Code: bf dc 5f f9 0f 0b e9 ad fd ff ff e8 23 97 96 f9 48 c7 c6 20 fc f9 88  
48 c7 c7 e0 fb f9 88 c6 05 ac 7d 4b 02 01 e8 99 dc 5f f9 <0f> 0b e9 87 fd  
ff ff 48 89 cf e8 2a 7b da f9 e9 e7 f9 ff ff 48 89
RSP: 0018:ffff8880a0e9ec60 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81683f55 RDI: 0000000000000005
RBP: ffff8880a0e9ed78 R08: ffff888090ed6580 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888086d356a0 R14: ffffed10141d3da2 R15: ffff888086d356a0
 hsr_xmit net/hsr/hsr_forward.c:230 [inline]
 hsr_forward_do net/hsr/hsr_forward.c:295 [inline]
 hsr_forward_skb+0x1e68/0x28a0 net/hsr/hsr_forward.c:373
 hsr_dev_xmit+0x71/0xa0 net/hsr/hsr_device.c:243
 __netdev_start_xmit include/linux/netdevice.h:4382 [inline]
 netdev_start_xmit include/linux/netdevice.h:4391 [inline]
 xmit_one net/core/dev.c:3278 [inline]
 dev_hard_start_xmit+0x286/0xc80 net/core/dev.c:3294
 __dev_queue_xmit+0x2f62/0x3ac0 net/core/dev.c:3864
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3897
 packet_snd net/packet/af_packet.c:2932 [inline]
 packet_sendmsg+0x298a/0x6ad0 net/packet/af_packet.c:2957
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:631
 __sys_sendto+0x3d7/0x670 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto net/socket.c:1796 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1796
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x442129
Code: e8 4c 06 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7  
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff  
ff 0f 83 7b 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffb6839fa8 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000442129
RDX: 0000000000000011 RSI: 0000000020000140 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000216 R12: 0000000000000000
R13: 00007fffb6839ff0 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..


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