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1
WARNING: net/bridge/netfilter/nf_conntrack_bridge.c:356 at nf_ct_bridge_refrag net/bridge/netfilter/nf_conntrack_bridge.c:356 [inline], CPU#0: syz.5.137/6418
WARNING: net/bridge/netfilter/nf_conntrack_bridge.c:356 at nf_ct_bridge_post+0x42e/0x1110 net/bridge/netfilter/nf_conntrack_bridge.c:407, CPU#0: syz.5.137/6418
Modules linked in:
CPU: 0 UID: 0 PID: 6418 Comm: syz.5.137 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:nf_ct_bridge_refrag net/bridge/netfilter/nf_conntrack_bridge.c:356 [inline]
RIP: 0010:nf_ct_bridge_post+0x42e/0x1110 net/bridge/netfilter/nf_conntrack_bridge.c:407
Code: 88 f7 49 8b 36 4c 89 ff 48 89 da 48 8d 8c 24 40 01 00 00 49 c7 c0 e0 d9 ac 8a e8 1d 48 e1 ff e9 93 09 00 00 e8 f3 c3 19 f7 90 <0f> 0b 90 45 31 ff 4c 8b 64 24 18 e9 83 09 00 00 e8 dd c3 19 f7 eb
RSP: 0018:ffffc90002bbebe0 EFLAGS: 00010293
RAX: ffffffff8aacbe9d RBX: ffff888012b0c140 RCX: ffff888035b54a80
RDX: 0000000000000000 RSI: ffffffff90192fa0 RDI: 0000000000000081
RBP: ffffc90002bbedc0 R08: ffff888035b54a80 R09: 0000000000000002
R10: 000000000000dd86 R11: 0000000000000000 R12: 0000000000000081
R13: dffffc0000000000 R14: ffffc90002bbee80 R15: 1ffff1100256182e
FS:  00007fed825606c0(0000) GS:ffff88808c54e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6c6f53c7bc CR3: 0000000040e2f000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
 nf_hook include/linux/netfilter.h:273 [inline]
 NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:316
 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66
 NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318
 __br_forward+0x397/0x540 net/bridge/br_forward.c:115
 deliver_clone net/bridge/br_forward.c:131 [inline]
 maybe_deliver net/bridge/br_forward.c:191 [inline]
 br_flood+0x3e6/0x8d0 net/bridge/br_forward.c:245
 br_handle_frame_finish+0x1175/0x1990 net/bridge/br_input.c:229
 nf_hook_bridge_pre net/bridge/br_input.c:313 [inline]
 br_handle_frame+0x81b/0x1510 net/bridge/br_input.c:442
 __netif_receive_skb_core+0x989/0x30b0 net/core/dev.c:6093
 __netif_receive_skb_one_core net/core/dev.c:6204 [inline]
 __netif_receive_skb net/core/dev.c:6319 [inline]
 netif_receive_skb_internal net/core/dev.c:6405 [inline]
 netif_receive_skb+0x1fe/0xbf0 net/core/dev.c:6464
 tun_rx_batched+0x1de/0x790 drivers/net/tun.c:1518
 tun_get_user+0x2b44/0x4370 drivers/net/tun.c:1986
 tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:2032
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x612/0xba0 fs/read_write.c:687
 ksys_write+0x150/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fed8175b74e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007fed8255ffb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fed825606c0 RCX: 00007fed8175b74e
RDX: 000000000000004e RSI: 0000200000000500 RDI: 00000000000000c8
RBP: 00007fed8182dee0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fed81a06128 R14: 00007fed81a06090 R15: 00007ffe8d932718
 </TASK>