WARNING in geneve_exit_batch_net (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    f8788d86 Linux 5.6-rc3
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=138dd22de00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5d2e033af114153f
dashboard link: https://syzkaller.appspot.com/bug?extid=68a8ed58e3d17c700de5
compiler:       clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16601d31e00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14fdf8f9e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+68a8ed58e3d17c700de5@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 0 PID: 304 at drivers/net/geneve.c:1849 geneve_destroy_tunnels drivers/net/geneve.c:1849 [inline]
WARNING: CPU: 0 PID: 304 at drivers/net/geneve.c:1849 geneve_exit_batch_net+0x2b1/0x300 drivers/net/geneve.c:1859
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 304 Comm: kworker/u4:4 Not tainted 5.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fb/0x318 lib/dump_stack.c:118
 panic+0x264/0x7a9 kernel/panic.c:221
 __warn+0x209/0x210 kernel/panic.c:582
 report_bug+0x1b6/0x2f0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0xcf/0x1c0 arch/x86/kernel/traps.c:267
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:geneve_destroy_tunnels drivers/net/geneve.c:1849 [inline]
RIP: 0010:geneve_exit_batch_net+0x2b1/0x300 drivers/net/geneve.c:1859
Code: 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 46 aa d1 fc 48 8b 1b 4c 39 fb 74 13 e8 c9 80 94 fc e9 f4 fd ff ff e8 bf 80 94 fc <0f> 0b eb cf e8 b6 80 94 fc eb 05 e8 af 80 94 fc 48 8d 7d c0 e8 c6
RSP: 0018:ffffc90001917c08 EFLAGS: 00010293
RAX: ffffffff84e288c1 RBX: ffff8880a7bc6120 RCX: ffff8880a88304c0
RDX: 0000000000000000 RSI: ffffc90001917c28 RDI: ffff8880a47da068
RBP: ffffc90001917c68 R08: ffffffff866be459 R09: fffffbfff12b21a9
R10: fffffbfff12b21a9 R11: 0000000000000000 R12: ffffc90001917c28
R13: dffffc0000000000 R14: ffff8880a1ca0dd0 R15: ffffc90001917c98
 ops_exit_list net/core/net_namespace.c:175 [inline]
 cleanup_net+0x78b/0xb80 net/core/net_namespace.c:589
 process_one_work+0x7f5/0x10f0 kernel/workqueue.c:2264
 worker_thread+0xbbc/0x1630 kernel/workqueue.c:2410
 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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