WARNING in batadv_iv_send_outstanding_bat_ogm_packet

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    da940012 Merge tag 'char-misc-5.4-rc3' of git://git.kernel..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13ffd808e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2d2fd92a28d3e50
dashboard link: https://syzkaller.appspot.com/bug?extid=c0b807de416427ff3dd1
compiler:       clang version 9.0.0 (/home/glider/llvm/clang  
80fee25776c2fb61e74c1ecb1a523375c2500b69)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=141ffd77600000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11edd580e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c0b807de416427ff3dd1@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 1 PID: 30 at net/batman-adv/bat_iv_ogm.c:382  
batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:382 [inline]
WARNING: CPU: 1 PID: 30 at net/batman-adv/bat_iv_ogm.c:382  
batadv_iv_send_outstanding_bat_ogm_packet+0x6b4/0x770  
net/batman-adv/bat_iv_ogm.c:1663
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 30 Comm: kworker/u4:2 Not tainted 5.4.0-rc2+ #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:77 [inline]
 dump_stack+0x1d8/0x2f8 lib/dump_stack.c:113
 panic+0x264/0x7a9 kernel/panic.c:221
 __warn+0x20e/0x210 kernel/panic.c:582
 report_bug+0x1b6/0x2f0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 do_error_trap+0xd7/0x440 arch/x86/kernel/traps.c:272
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:291
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
RIP: 0010:batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:382 [inline]
RIP: 0010:batadv_iv_send_outstanding_bat_ogm_packet+0x6b4/0x770  
net/batman-adv/bat_iv_ogm.c:1663
Code: 66 05 00 eb 05 e8 9c 48 23 fa 48 83 c4 68 5b 41 5c 41 5d 41 5e 41 5f  
5d c3 e8 88 48 23 fa 0f 0b e9 34 ff ff ff e8 7c 48 23 fa <0f> 0b e9 28 ff  
ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c c1 f9 ff
RSP: 0018:ffff8880a9abfc48 EFLAGS: 00010293
RAX: ffffffff874fe8a4 RBX: ffff888094160870 RCX: ffff8880a9ab2080
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffff8880a9abfcd8 R08: ffffffff874fe28e R09: ffffed10123e6969
R10: ffffed10123e6969 R11: 0000000000000000 R12: ffff888091f34000
R13: dffffc0000000000 R14: ffff8880a80c5000 R15: ffff8880a4481400
 process_one_work+0x7ef/0x10e0 kernel/workqueue.c:2269
 worker_thread+0xc01/0x1630 kernel/workqueue.c:2415
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..


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