------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 5205 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25
Modules linked in:
CPU: 0 UID: 0 PID: 5205 Comm: udevd 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: e91d56f06a511600 RBX: 0000000000000002 RCX: ffff88807d4a1e00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc900000079b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfaa44 R12: ffff8880298b0000
R13: dffffc0000000000 R14: ffff8880298b016c R15: ffff88802f20d000
FS: 00007f2fc1b4e880(0000) GS:ffff888125c55000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2683ad9000 CR3: 0000000032658000 CR4: 00000000003526f0
Call Trace:
__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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 ab bb 5f f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 d3 aa 28 f6 65 8b 05 bc 83 34 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc90003337c40 EFLAGS: 00000206
RAX: e91d56f06a511600 RBX: 0000000000000a06 RCX: e91d56f06a511600
RDX: 0000000000000000 RSI: ffffffff8d97cb85 RDI: 0000000000000001
RBP: ffffc90003337cc0 R08: ffffffff8fa100f7 R09: 1ffffffff1f4201e
R10: dffffc0000000000 R11: fffffbfff1f4201f R12: dffffc0000000000
R13: ffff888034847600 R14: ffffffff99cb7e48 R15: 1ffff92000666f88
__debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
debug_check_no_obj_freed+0x451/0x470 lib/debugobjects.c:1129
slab_free_hook mm/slub.c:2312 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x113/0x400 mm/slub.c:4745
do_unlinkat+0x509/0x560 fs/namei.c:4673
__do_sys_unlink fs/namei.c:4696 [inline]
__se_sys_unlink fs/namei.c:4694 [inline]
__x64_sys_unlink+0x47/0x50 fs/namei.c:4694
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: 0033:0x7f2fc1c48937
Code: 00 00 e9 a9 fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 5f 00 00 00 0f 05 c3 0f 1f 84 00 00 00 00 00 b8 57 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 91 b4 0d 00 f7 d8 64 89 02 b8
RSP: 002b:00007fff8147b478 EFLAGS: 00000202 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000bb8 RCX: 00007f2fc1c48937
RDX: 0000000000000000 RSI: 00000000699e9300 RDI: 000055f7bef0902e
RBP: 0000000000000000 R08: 00000000699ff269 R09: 7fffffffffffffff
R10: 3fffffffffffffff R11: 0000000000000202 R12: 0000000000000000
R13: 000055f7bef24100 R14: 0000000000000001 R15: 0000000000000000
----------------
Code disassembly (best guess):
0: 74 05 je 0x7
2: e8 ab bb 5f f6 call 0xf65fbbb2
7: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp)
e: 00 00
10: 9c pushf
11: 8f 44 24 20 pop 0x20(%rsp)
15: f6 44 24 21 02 testb $0x2,0x21(%rsp)
1a: 75 4f jne 0x6b
1c: f7 c3 00 02 00 00 test $0x200,%ebx
22: 74 01 je 0x25
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 d3 aa 28 f6 call 0xf628ab02 <-- trapping instruction
2f: 65 8b 05 bc 83 34 07 mov %gs:0x73483bc(%rip),%eax # 0x73483f2
36: 85 c0 test %eax,%eax
38: 74 40 je 0x7a
3a: 48 rex.W
3b: c7 .byte 0xc7
3c: 04 24 add $0x24,%al
3e: 0e (bad)
3f: 36 ss