------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 6551 at lib/refcount.c:25 refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 0 PID: 6551 Comm: syz.0.680 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25
Code: 09 01 48 c7 c7 40 6b 59 8a e8 dd 27 bb 05 0f 0b eb e0 e8 04 42 9c fd c6 05 ae 8f 79 09 01 48 c7 c7 80 6a 59 8a e8 c1 27 bb 05 <0f> 0b eb c4 e8 e8 41 9c fd c6 05 93 8f 79 09 01 48 c7 c7 e0 6a 59
RSP: 0018:ffffc90000007848 EFLAGS: 00010246
RAX: f8f35b50b1376300 RBX: 0000000000000002 RCX: ffff8880204e5940
RDX: 0000000000000100 RSI: 0000000000000101 RDI: 0000000000000000
RBP: ffffc900000079b0 R08: dffffc0000000000 R09: ffffed1017204f24
R10: ffffed1017204f24 R11: 1ffff11017204f23 R12: ffff888019fbcf80
R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000000
FS: 00007f02599096c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001dc0 CR3: 0000000021f10000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 3a810b1eb6134bdc DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__refcount_add include/linux/refcount.h:-1 [inline]
__refcount_inc include/linux/refcount.h:250 [inline]
refcount_inc include/linux/refcount.h:267 [inline]
get_net include/net/net_namespace.h:252 [inline]
tipc_aead_encrypt net/tipc/crypto.c:832 [inline]
tipc_crypto_xmit+0x1949/0x2560 net/tipc/crypto.c:1772
tipc_bearer_xmit_skb+0x228/0x3c0 net/tipc/bearer.c:574
tipc_disc_timeout+0x568/0x6b0 net/tipc/discover.c:338
call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
expire_timers kernel/time/timer.c:1496 [inline]
__run_timers+0x525/0x7c0 kernel/time/timer.c:1767
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
handle_softirqs+0x328/0x820 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:console_unlock+0xd90/0x1200 kernel/printk/printk.c:2749
Code: 00 48 83 7c 24 28 00 75 19 e8 ec 9e 18 00 eb 18 e8 e5 9e 18 00 e8 80 49 42 08 48 83 7c 24 28 00 74 e7 e8 d3 9e 18 00 fb 31 ff <89> de e8 29 a2 18 00 85 db 0f 94 c0 22 44 24 17 3c 01 75 1f e8 b7
RSP: 0018:ffffc90003356280 EFLAGS: 00000246
RAX: ffffffff815f234d RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9000c571000 RSI: 000000000007ffff RDI: 0000000000000000
RBP: ffffc900033564f0 R08: dffffc0000000000 R09: fffffbfff1ff3619
R10: fffffbfff1ff3619 R11: 1ffffffff1ff3618 R12: 1ffffffff194c725
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffffffff194c71e
vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274
dev_vprintk_emit+0x2cc/0x350 drivers/base/core.c:4638
dev_printk_emit+0xdd/0x120 drivers/base/core.c:4649
__netdev_printk+0x2ef/0x3d0 net/core/dev.c:11504
netdev_info+0x107/0x150 net/core/dev.c:11559
nsim_udp_tunnel_set_port+0x293/0x430 drivers/net/netdevsim/udp_tunnels.c:34
udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline]
udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:246 [inline]
__udp_tunnel_nic_device_sync+0x9d2/0x1320 net/ipv4/udp_tunnel_nic.c:289
udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:312 [inline]
__udp_tunnel_nic_add_port+0xb83/0xe80 net/ipv4/udp_tunnel_nic.c:531
udp_tunnel_nic_add_port include/net/udp_tunnel.h:336 [inline]
udp_tunnel_push_rx_port+0x177/0x1f0 net/ipv4/udp_tunnel_core.c:98
geneve_offload_rx_ports+0x130/0x210 drivers/net/geneve.c:1238
geneve_netdevice_event+0x66/0x80 drivers/net/geneve.c:-1
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
call_netdevice_notifiers_extack net/core/dev.c:2061 [inline]
call_netdevice_notifiers+0x85/0xc0 net/core/dev.c:2075
udp_tunnel_get_rx_info include/net/udp_tunnel.h:138 [inline]
udp_tunnel_nic_register net/ipv4/udp_tunnel_nic.c:830 [inline]
udp_tunnel_nic_netdevice_event+0xbbc/0x13b0 net/ipv4/udp_tunnel_nic.c:898
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
call_netdevice_notifiers_extack net/core/dev.c:2061 [inline]
call_netdevice_notifiers net/core/dev.c:2075 [inline]
register_netdevice+0x1275/0x16b0 net/core/dev.c:10428
nsim_init_netdevsim drivers/net/netdevsim/netdev.c:317 [inline]
nsim_create+0x32d/0x3e0 drivers/net/netdevsim/netdev.c:365
__nsim_dev_port_add+0x5c7/0x980 drivers/net/netdevsim/dev.c:1312
nsim_dev_port_add_all+0x37/0x100 drivers/net/netdevsim/dev.c:1372
nsim_dev_reload_create drivers/net/netdevsim/dev.c:1421 [inline]
nsim_dev_reload_up+0x48b/0x7f0 drivers/net/netdevsim/dev.c:910
devlink_reload+0x342/0x770 net/core/devlink.c:3970
devlink_nl_cmd_reload+0xbf6/0xe10 net/core/devlink.c:4084
genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
genl_rcv_msg+0xbc6/0xf40 net/netlink/genetlink.c:792
netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2489
genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
netlink_unicast+0x77c/0x920 net/netlink/af_netlink.c:1337
netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436
___sys_sendmsg+0x1f0/0x260 net/socket.c:2490
__sys_sendmsg net/socket.c:2519 [inline]
__do_sys_sendmsg net/socket.c:2528 [inline]
__se_sys_sendmsg+0x190/0x250 net/socket.c:2526
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f025baa1929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0259909038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f025bcc8fa0 RCX: 00007f025baa1929
RDX: 0000000000000000 RSI: 0000200000000080 RDI: 0000000000000003
RBP: 00007f025bb23b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f025bcc8fa0 R15: 00007fff8b654ce8
----------------
Code disassembly (best guess):
0: 00 48 83 add %cl,-0x7d(%rax)
3: 7c 24 jl 0x29
5: 28 00 sub %al,(%rax)
7: 75 19 jne 0x22
9: e8 ec 9e 18 00 call 0x189efa
e: eb 18 jmp 0x28
10: e8 e5 9e 18 00 call 0x189efa
15: e8 80 49 42 08 call 0x842499a
1a: 48 83 7c 24 28 00 cmpq $0x0,0x28(%rsp)
20: 74 e7 je 0x9
22: e8 d3 9e 18 00 call 0x189efa
27: fb sti
28: 31 ff xor %edi,%edi
* 2a: 89 de mov %ebx,%esi <-- trapping instruction
2c: e8 29 a2 18 00 call 0x18a25a
31: 85 db test %ebx,%ebx
33: 0f 94 c0 sete %al
36: 22 44 24 17 and 0x17(%rsp),%al
3a: 3c 01 cmp $0x1,%al
3c: 75 1f jne 0x5d
3e: e8 .byte 0xe8
3f: b7 .byte 0xb7