------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 12892 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25
Modules linked in:
CPU: 1 UID: 0 PID: 12892 Comm: syz.0.1713 Not tainted 6.15.0-syzkaller-12058-g64980441d269 #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 63 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 44 ca c9 0a 01 90 48 c7 c7
RSP: 0018:ffffc90000a08828 EFLAGS: 00010246
RAX: c4555aea42557700 RBX: 0000000000000002 RCX: ffff8880226e3c00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc90000a089b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfaa44 R12: ffff888033e18000
R13: dffffc0000000000 R14: ffff888033e1816c R15: ffff888057256000
FS:  00007ff4048536c0(0000) GS:ffff888125d55000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555574291588 CR3: 000000001d2e6000 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:lock_is_held_type+0x137/0x190 kernel/locking/lockdep.c:5948
Code: 01 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 05 09 03 37 07 <48> 3b 44 24 08 75 43 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc9000455f8d8 EFLAGS: 00000206
RAX: c4555aea42557700 RBX: 0000000000000000 RCX: c4555aea42557700
RDX: 0000000000000000 RSI: ffffffff8db695db RDI: ffffffff8be28340
RBP: 00000000ffffffff R08: ffff8880226e3c07 R09: 1ffff110044dc780
R10: dffffc0000000000 R11: ffffed10044dc781 R12: 0000000000000246
R13: ffff8880226e3c00 R14: ffffffff8e13f0c0 R15: 0000000000000001
 lock_is_held include/linux/lockdep.h:249 [inline]
 __might_resched+0xa6/0x610 kernel/sched/core.c:8762
 __get_user_pages+0x673/0x30b0 mm/gup.c:1484
 populate_vma_page_range+0x26b/0x340 mm/gup.c:1926
 __mm_populate+0x24c/0x380 mm/gup.c:2029
 mm_populate include/linux/mm.h:3348 [inline]
 vm_mmap_pgoff+0x3f0/0x4c0 mm/util.c:584
 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: 0033:0x7ff40398e929
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:00007ff404853038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ff403bb5fa0 RCX: 00007ff40398e929
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007ff403a10b39 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff403bb5fa0 R15: 00007ff403cdfa28
 </TASK>
----------------
Code disassembly (best guess):
   0:	01 75 44             	add    %esi,0x44(%rbp)
   3:	48 c7 04 24 00 00 00 	movq   $0x0,(%rsp)
   a:	00
   b:	9c                   	pushf
   c:	8f 04 24             	pop    (%rsp)
   f:	f7 04 24 00 02 00 00 	testl  $0x200,(%rsp)
  16:	75 4c                	jne    0x64
  18:	41 f7 c4 00 02 00 00 	test   $0x200,%r12d
  1f:	74 01                	je     0x22
  21:	fb                   	sti
  22:	65 48 8b 05 09 03 37 	mov    %gs:0x7370309(%rip),%rax        # 0x7370333
  29:	07
* 2a:	48 3b 44 24 08       	cmp    0x8(%rsp),%rax <-- trapping instruction
  2f:	75 43                	jne    0x74
  31:	89 d8                	mov    %ebx,%eax
  33:	48 83 c4 10          	add    $0x10,%rsp
  37:	5b                   	pop    %rbx
  38:	41 5c                	pop    %r12
  3a:	41 5d                	pop    %r13
  3c:	41 5e                	pop    %r14
  3e:	41 5f                	pop    %r15