------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 5140 at lib/refcount.c:25 refcount_warn_saturate+0xf3/0x1b0 lib/refcount.c:25
Modules linked in:
CPU: 0 PID: 5140 Comm: udevd Not tainted 6.6.93-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:refcount_warn_saturate+0xf3/0x1b0 lib/refcount.c:25
Code: 15 0a 01 0f 85 98 00 00 00 e8 39 41 66 fd 5b 41 5e c3 e8 30 41 66 fd c6 05 e1 00 15 0a 01 48 c7 c7 40 0f fc 8a e8 0d a5 30 fd <0f> 0b eb e0 e8 14 41 66 fd c6 05 c6 00 15 0a 01 48 c7 c7 a0 0f fc
RSP: 0018:ffffc90000007848 EFLAGS: 00010246
RAX: c7fdc9513f520800 RBX: 0000000000000002 RCX: ffff88807d6f5a00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc900000079d0 R08: ffffc90000007447 R09: 1ffff92000000e88
R10: dffffc0000000000 R11: fffff52000000e89 R12: ffff88807aff8000
R13: dffffc0000000000 R14: ffff88807aff8154 R15: ffff88805e349c00
FS: 00007f048b992880(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f51ae56c0 CR3: 0000000018ef8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__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:261 [inline]
tipc_aead_encrypt net/tipc/crypto.c:821 [inline]
tipc_crypto_xmit+0x17cf/0x2250 net/tipc/crypto.c:1761
tipc_bearer_xmit_skb+0x246/0x3f0 net/tipc/bearer.c:572
tipc_disc_timeout+0x581/0x6d0 net/tipc/discover.c:338
call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700
expire_timers kernel/time/timer.c:1751 [inline]
__run_timers+0x52d/0x7d0 kernel/time/timer.c:2022
run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:-1 [inline]
RIP: 0010:unwind_next_frame+0x1a8/0x2970 arch/x86/kernel/unwind_orc.c:494
Code: 48 89 df 4c 89 fe e8 a7 04 4b 00 4c 29 fb 4c 89 24 24 4c 89 74 24 08 75 11 e8 84 02 4b 00 48 c7 c3 60 35 a8 8a e9 65 04 00 00 <49> 89 df 48 89 6c 24 10 48 c7 c3 00 00 00 81 4c 89 ff 48 c7 c6 00
RSP: 0018:ffffc90003287458 EFLAGS: 00000282
RAX: ffffffff813a9449 RBX: ffffffff81de100d RCX: ffff88807d6f5a00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff81de100e
RBP: ffffc90003287578 R08: ffffc900032875f0 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000000 R12: ffffc90003287528
R13: dffffc0000000000 R14: ffffc9000328755d R15: 0000000000000001
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
slab_alloc_node mm/slub.c:3485 [inline]
slab_alloc mm/slub.c:3493 [inline]
__kmem_cache_alloc_lru mm/slub.c:3500 [inline]
kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3509
kmem_cache_zalloc include/linux/slab.h:711 [inline]
alloc_empty_file+0x9e/0x1d0 fs/file_table.c:206
path_openat+0x100/0x3190 fs/namei.c:3775
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f048b315c3a
Code: 41 89 f2 48 89 54 24 e0 41 83 e2 40 75 2a 89 f0 f7 d0 a9 00 00 41 00 74 1f 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff 77 2e c3 0f 1f 44 00 00 48 8d 44 24 08 c7 44 24
RSP: 002b:00007ffef77aa578 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000056433203a560 RCX: 00007f048b315c3a
RDX: 0000000000090800 RSI: 0000564331fdd3e0 RDI: 00000000ffffff9c
RBP: 0000564331fdd3e0 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000206 R12: 0000564331ff0760
R13: 00000000000000ff R14: 0000564304c54be0 R15: 00007ffef77aa820
----------------
Code disassembly (best guess):
0: 48 89 df mov %rbx,%rdi
3: 4c 89 fe mov %r15,%rsi
6: e8 a7 04 4b 00 call 0x4b04b2
b: 4c 29 fb sub %r15,%rbx
e: 4c 89 24 24 mov %r12,(%rsp)
12: 4c 89 74 24 08 mov %r14,0x8(%rsp)
17: 75 11 jne 0x2a
19: e8 84 02 4b 00 call 0x4b02a2
1e: 48 c7 c3 60 35 a8 8a mov $0xffffffff8aa83560,%rbx
25: e9 65 04 00 00 jmp 0x48f
* 2a: 49 89 df mov %rbx,%r15 <-- trapping instruction
2d: 48 89 6c 24 10 mov %rbp,0x10(%rsp)
32: 48 c7 c3 00 00 00 81 mov $0xffffffff81000000,%rbx
39: 4c 89 ff mov %r15,%rdi
3c: 48 rex.W
3d: c7 .byte 0xc7
3e: c6 .byte 0xc6