------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 14693 at lib/refcount.c:25 refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 0 PID: 14693 Comm: syz.6.2395 Not tainted 6.1.141-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 a0 d2 be 8a e8 ad 30 45 fd 0f 0b eb e0 e8 f4 1d 79 fd c6 05 fa 72 e2 09 01 48 c7 c7 e0 d1 be 8a e8 91 30 45 fd <0f> 0b eb c4 e8 d8 1d 79 fd c6 05 df 72 e2 09 01 48 c7 c7 40 d2 be
RSP: 0018:ffffc90000007828 EFLAGS: 00010246
RAX: 4be259895bc15f00 RBX: 0000000000000002 RCX: ffff88801b3ebb80
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc90000007990 R08: dffffc0000000000 R09: fffff52000000e95
R10: fffff52000000e95 R11: 1ffff92000000e94 R12: ffff88805ad3b880
R13: dffffc0000000000 R14: 0000000000000002 R15: ffff8880571d8448
FS:  00007f0acb1606c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2823d9 CR3: 000000007794e000 CR4: 00000000003506f0
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:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 get_net include/net/net_namespace.h:257 [inline]
 tipc_aead_encrypt net/tipc/crypto.c:821 [inline]
 tipc_crypto_xmit+0x17a9/0x2300 net/tipc/crypto.c:1761
 tipc_bearer_xmit_skb+0x242/0x3f0 net/tipc/bearer.c:574
 tipc_disc_timeout+0x568/0x6b0 net/tipc/discover.c:338
 call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1820
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:check_preemption_disabled+0x13/0x110 lib/smp_processor_id.c:13
Code: 00 cc cc 00 00 cc cc 48 c7 c7 00 13 bf 8a 48 c7 c6 40 13 bf 8a eb 00 55 41 57 41 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 <48> 89 44 24 08 65 8b 05 b1 73 f2 75 65 8b 0d 52 c9 f2 75 f7 c1 ff
RSP: 0018:ffffc90003bef5c8 EFLAGS: 00000282
RAX: 4be259895bc15f00 RBX: 0000000000000000 RCX: ffffffff8162eaa9
RDX: 0000000000000000 RSI: ffffffff8abf1340 RDI: ffffffff8abf1300
RBP: ffffc90003bef738 R08: dffffc0000000000 R09: fffffbfff1bfd0b6
R10: fffffbfff1bfd0b6 R11: 1ffffffff1bfd0b5 R12: 0000000000000000
R13: 1ffff9200077ded0 R14: 0000000000000000 R15: dffffc0000000000
 rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
 rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:721
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xe8/0x490 kernel/locking/lockdep.c:5633
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 unix_dgram_sendmsg+0x937/0x16c0 net/unix/af_unix.c:1978
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x59b/0x970 net/socket.c:2519
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573
 __sys_sendmmsg+0x272/0x490 net/socket.c:2659
 __do_sys_sendmmsg net/socket.c:2688 [inline]
 __se_sys_sendmmsg net/socket.c:2685 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2685
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0aca38e929
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:00007f0acb160038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f0aca5b5fa0 RCX: 00007f0aca38e929
RDX: 0000000000000651 RSI: 0000200000000000 RDI: 0000000000000006
RBP: 00007f0aca410b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0aca5b5fa0 R15: 00007ffe51f41448
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 cc                	add    %cl,%ah
   2:	cc                   	int3
   3:	00 00                	add    %al,(%rax)
   5:	cc                   	int3
   6:	cc                   	int3
   7:	48 c7 c7 00 13 bf 8a 	mov    $0xffffffff8abf1300,%rdi
   e:	48 c7 c6 40 13 bf 8a 	mov    $0xffffffff8abf1340,%rsi
  15:	eb 00                	jmp    0x17
  17:	55                   	push   %rbp
  18:	41 57                	push   %r15
  1a:	41 56                	push   %r14
  1c:	53                   	push   %rbx
  1d:	48 83 ec 10          	sub    $0x10,%rsp
  21:	65 48 8b 04 25 28 00 	mov    %gs:0x28,%rax
  28:	00 00
* 2a:	48 89 44 24 08       	mov    %rax,0x8(%rsp) <-- trapping instruction
  2f:	65 8b 05 b1 73 f2 75 	mov    %gs:0x75f273b1(%rip),%eax        # 0x75f273e7
  36:	65 8b 0d 52 c9 f2 75 	mov    %gs:0x75f2c952(%rip),%ecx        # 0x75f2c98f
  3d:	f7                   	.byte 0xf7
  3e:	c1                   	.byte 0xc1
  3f:	ff                   	.byte 0xff