------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 16509 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25
Modules linked in:
CPU: 1 UID: 0 PID: 16509 Comm: syz.1.3022 Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25
Code: 00 00 e8 69 7e 07 fd 5b 41 5e e9 81 eb a6 06 cc e8 5b 7e 07 fd c6 05 1b e0 d0 0a 01 90 48 c7 c7 c0 45 e1 8b e8 c7 6a cb fc 90 <0f> 0b 90 90 eb d7 e8 3b 7e 07 fd c6 05 fc df d0 0a 01 90 48 c7 c7
RSP: 0018:ffffc90000a08828 EFLAGS: 00010246
RAX: d0ff5f92b105bc00 RBX: 0000000000000002 RCX: ffff88807f181e00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc90000a089b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfa66c R12: ffff888033650000
R13: dffffc0000000000 R14: ffff88803365016c R15: ffff888031d5fc00
FS:  00007fbc1be316c0(0000) GS:ffff888125d98000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f805704f3c1 CR3: 000000004b372000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __refcount_add include/linux/refcount.h:-1 [inline]
 __refcount_inc include/linux/refcount.h:366 [inline]
 refcount_inc include/linux/refcount.h:383 [inline]
 get_net include/net/net_namespace.h:268 [inline]
 tipc_aead_encrypt net/tipc/crypto.c:821 [inline]
 tipc_crypto_xmit+0x1820/0x22c0 net/tipc/crypto.c:1761
 tipc_bearer_xmit_skb+0x245/0x400 net/tipc/bearer.c:572
 tipc_disc_timeout+0x580/0x6d0 net/tipc/discover.c:338
 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1798 [inline]
 __run_timers kernel/time/timer.c:2372 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
 run_timer_base kernel/time/timer.c:2393 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5260
Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 ef 70 cd 09 e8 0a d2 35 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc90004b67238 EFLAGS: 00000282
RAX: d0ff5f92b105bc00 RBX: 0000000000000000 RCX: d0ff5f92b105bc00
RDX: 0000000000000000 RSI: ffffffff8d959ac8 RDI: ffffffff8be19040
RBP: ffffc90004b67290 R08: ffffffff8f9f8bf7 R09: 1ffffffff1f3f17e
R10: dffffc0000000000 R11: fffffbfff1f3f17f R12: ffff88807f181e00
R13: dffffc0000000000 R14: ffff8880327d8000 R15: ffff8880b873c418
 context_switch kernel/sched/core.c:5395 [inline]
 __schedule+0x16aa/0x4cb0 kernel/sched/core.c:6781
 __schedule_loop kernel/sched/core.c:6859 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6874
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 unix_wait_for_peer+0x1e9/0x2e0 net/unix/af_unix.c:1585
 unix_dgram_sendmsg+0xb1f/0x1870 net/unix/af_unix.c:2187
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:727
 ____sys_sendmsg+0x52d/0x830 net/socket.c:2566
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
 __sys_sendmmsg+0x227/0x430 net/socket.c:2709
 __do_sys_sendmmsg net/socket.c:2736 [inline]
 __se_sys_sendmmsg net/socket.c:2733 [inline]
 __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2733
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbc1af8e969
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:00007fbc1be31038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fbc1b1b5fa0 RCX: 00007fbc1af8e969
RDX: 0000000000000651 RSI: 0000200000000000 RDI: 0000000000000004
RBP: 00007fbc1b010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbc1b1b5fa0 R15: 00007fffe9096348
 </TASK>
----------------
Code disassembly (best guess):
   0:	0f 84 3c 01 00 00    	je     0x142
   6:	48 85 db             	test   %rbx,%rbx
   9:	0f 85 63 01 00 00    	jne    0x172
   f:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  14:	4c 8b 75 d0          	mov    -0x30(%rbp),%r14
  18:	4c 89 e7             	mov    %r12,%rdi
  1b:	e8 ef 70 cd 09       	call   0x9cd710f
  20:	e8 0a d2 35 00       	call   0x35d22f
  25:	fb                   	sti
  26:	4c 8b 65 c0          	mov    -0x40(%rbp),%r12
* 2a:	49 8d bc 24 18 16 00 	lea    0x1618(%r12),%rdi <-- trapping instruction
  31:	00
  32:	48 89 f8             	mov    %rdi,%rax
  35:	48 c1 e8 03          	shr    $0x3,%rax
  39:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
  3e:	84 c0                	test   %al,%al