------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 8177 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25
Modules linked in:
CPU: 0 UID: 0 PID: 8177 Comm: syz.0.647 Not tainted 6.15.0-syzkaller-12293-g7fdaba912981 #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 09 2d ff fc 5b 41 5e e9 d1 4a a7 06 cc e8 fb 2c ff fc c6 05 e3 ca c9 0a 01 90 48 c7 c7 c0 38 e2 8b e8 17 db c2 fc 90 <0f> 0b 90 90 eb d7 e8 db 2c ff fc c6 05 c4 ca c9 0a 01 90 48 c7 c7
RSP: 0018:ffffc90000007828 EFLAGS: 00010246
RAX: ebdf5f08f5056900 RBX: 0000000000000002 RCX: ffff888027503c00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc900000079b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfaa44 R12: ffff888033e2c100
R13: dffffc0000000000 R14: ffff888033e2c26c R15: ffff8880285ce000
FS:  0000000000000000(0000) GS:ffff888125c55000(0063) knlGS:00000000f50d6b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000008005a018 CR3: 00000000348ae000 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:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d 64 c8 f9 0b 48 89 de 5b e9 e3 ae 58 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 b0 9c 92 65 8b 15 48 54 dc 10 81 e2 00 01 ff 00
RSP: 0018:ffffc9001b5174d8 EFLAGS: 00000246
RAX: ffffffff8949ea2a RBX: ffffc9001b517748 RCX: 0000000000080000
RDX: ffffc9000c7f9000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9001b5175b0 R08: ffffc9001b51775f R09: 0000000000000000
R10: ffffc9001b517740 R11: fffff520036a2eec R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff920036a2ee9
 scm_destroy include/net/scm.h:87 [inline]
 __scm_recv_common+0x49a/0x610 net/core/scm.c:485
 scm_recv_unix+0xab/0x360 net/core/scm.c:521
 __unix_dgram_recvmsg+0xa18/0xde0 net/unix/af_unix.c:2584
 sock_recvmsg_nosec+0x183/0x1c0 net/socket.c:1017
 ____sys_recvmsg+0x3aa/0x460 net/socket.c:2784
 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2828
 do_recvmmsg+0x36a/0x770 net/socket.c:2915
 __sys_recvmmsg+0x19d/0x280 net/socket.c:2997
 __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
 __ia32_compat_sys_recvmmsg_time32+0xbf/0xe0 net/compat.c:414
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7fb4539
Code: 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f50d655c EFLAGS: 00000206 ORIG_RAX: 0000000000000151
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000800000c0
RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	8b 3d 64 c8 f9 0b    	mov    0xbf9c864(%rip),%edi        # 0xbf9c86a
   6:	48 89 de             	mov    %rbx,%rsi
   9:	5b                   	pop    %rbx
   a:	e9 e3 ae 58 00       	jmp    0x58aef2
   f:	cc                   	int3
  10:	cc                   	int3
  11:	cc                   	int3
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	90                   	nop
  1c:	90                   	nop
  1d:	90                   	nop
  1e:	90                   	nop
  1f:	90                   	nop
  20:	90                   	nop
  21:	90                   	nop
  22:	f3 0f 1e fa          	endbr64
  26:	48 8b 04 24          	mov    (%rsp),%rax
* 2a:	65 48 8b 0c 25 08 b0 	mov    %gs:0xffffffff929cb008,%rcx <-- trapping instruction
  31:	9c 92
  33:	65 8b 15 48 54 dc 10 	mov    %gs:0x10dc5448(%rip),%edx        # 0x10dc5482
  3a:	81 e2 00 01 ff 00    	and    $0xff0100,%edx