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@syzkaller.appspotmail.com

------------[ 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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