------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 5200 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25
Modules linked in:
CPU: 1 UID: 0 PID: 5200 Comm: udevd Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #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 19 6f 00 fd 5b 41 5e e9 81 eb a6 06 cc e8 0b 6f 00 fd c6 05 e7 f2 ca 0a 01 90 48 c7 c7 00 19 e2 8b e8 57 5b c4 fc 90 <0f> 0b 90 90 eb d7 e8 eb 6e 00 fd c6 05 c8 f2 ca 0a 01 90 48 c7 c7
RSP: 0018:ffffc90000a08828 EFLAGS: 00010246
RAX: fc839a91eccf7100 RBX: 0000000000000002 RCX: ffff88807e2e3c00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc90000a089b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfa66c R12: ffff888033aac100
R13: dffffc0000000000 R14: ffff888033aac26c R15: ffff8880323adc00
FS: 00007fee0e25f880(0000) GS:ffff888125d64000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6f40781c78 CR3: 00000000331b0000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 000000000000000b DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
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+0x17e/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:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x37/0x90 kernel/kcov.c:321
Code: 08 c0 9b 92 65 8b 15 48 90 db 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 3c 16 00 00 00 74 4e 8b 91 18 16 00 00 <83> fa 03 75 43 48 8b 91 20 16 00 00 44 8b 89 1c 16 00 00 49 c1 e1
RSP: 0018:ffffc90003267458 EFLAGS: 00000246
RAX: ffffffff8133852d RBX: 00007fee0db11000 RCX: ffff88807e2e3c00
RDX: 0000000000000000 RSI: 00007fee0db11000 RDI: ffffffffff600000
RBP: 0000000000000001 R08: 0000000000000022 R09: ffffffff81727865
R10: ffffc90003267518 R11: ffffffff81acc920 R12: ffff88807e2e3c00
R13: ffff888144313080 R14: dffffc0000000000 R15: 1ffff9200064cea2
in_gate_area_no_mm+0x3d/0x60 arch/x86/entry/vsyscall/vsyscall_64.c:321
is_kernel_text include/linux/kallsyms.h:31 [inline]
core_kernel_text kernel/extable.c:68 [inline]
kernel_text_address+0x2d/0xe0 kernel/extable.c:99
__kernel_text_address+0xd/0x40 kernel/extable.c:79
unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4327 [inline]
__kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4339
kmalloc_noprof include/linux/slab.h:909 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x213/0x4b0 security/tomoyo/file.c:822
security_inode_getattr+0x12f/0x330 security/security.c:2377
vfs_getattr fs/stat.c:259 [inline]
vfs_statx_path fs/stat.c:299 [inline]
vfs_statx+0x18e/0x550 fs/stat.c:356
vfs_fstatat+0x118/0x170 fs/stat.c:375
__do_sys_newfstatat fs/stat.c:542 [inline]
__se_sys_newfstatat fs/stat.c:536 [inline]
__x64_sys_newfstatat+0x116/0x190 fs/stat.c:536
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: 0033:0x7fee0db11b0a
Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7
RSP: 002b:00007ffdd9b17be8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffdd9b18080 RCX: 00007fee0db11b0a
RDX: 00007ffdd9b17bf0 RSI: 00007ffdd9b18080 RDI: 00000000ffffff9c
RBP: 00005652ab6bc910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdd9b17c80
R13: 000056526d48e100 R14: 00005652ab6cdc30 R15: 00007ffdd9b19580
----------------
Code disassembly (best guess):
0: 08 c0 or %al,%al
2: 9b fwait
3: 92 xchg %eax,%edx
4: 65 8b 15 48 90 db 10 mov %gs:0x10db9048(%rip),%edx # 0x10db9053
b: 81 e2 00 01 ff 00 and $0xff0100,%edx
11: 74 11 je 0x24
13: 81 fa 00 01 00 00 cmp $0x100,%edx
19: 75 57 jne 0x72
1b: 83 b9 3c 16 00 00 00 cmpl $0x0,0x163c(%rcx)
22: 74 4e je 0x72
24: 8b 91 18 16 00 00 mov 0x1618(%rcx),%edx
* 2a: 83 fa 03 cmp $0x3,%edx <-- trapping instruction
2d: 75 43 jne 0x72
2f: 48 8b 91 20 16 00 00 mov 0x1620(%rcx),%rdx
36: 44 8b 89 1c 16 00 00 mov 0x161c(%rcx),%r9d
3d: 49 rex.WB
3e: c1 .byte 0xc1
3f: e1 .byte 0xe1