------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 5770 at lib/refcount.c:25 refcount_warn_saturate+0xf3/0x1b0 lib/refcount.c:25
Modules linked in:
CPU: 0 PID: 5770 Comm: syz-executor 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: 90961c606791c400 RBX: 0000000000000002 RCX: ffff88802c050000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc900000079d0 R08: ffffc90000007447 R09: 1ffff92000000e88
R10: dffffc0000000000 R11: fffff52000000e89 R12: ffff888030393a80
R13: dffffc0000000000 R14: ffff888030393bd4 R15: ffff88801c39c400
FS: 000055558d67e500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2c810ff8 CR3: 00000000627d3000 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:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:127 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:178 [inline]
RIP: 0010:kasan_check_range+0x89/0x290 mm/kasan/generic.c:187
Code: 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 41 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 cc 01 00 00 49 ff c3 48 ff c3 75 ee e9 21 01 00 00 44 89 dd
RSP: 0018:ffffc9000461f6c8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff81684ced
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88805d34a3d8
RBP: 0000000000000000 R08: ffff88805d34a3db R09: 1ffff1100ba6947b
R10: dffffc0000000000 R11: ffffed100ba6947b R12: 0000000000000001
R13: 1ffff1100ba694ad R14: ffffed100ba6947c R15: 1ffff1100ba6947b
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
queued_spin_is_locked include/asm-generic/qspinlock.h:57 [inline]
debug_spin_unlock kernel/locking/spinlock_debug.c:100 [inline]
do_raw_spin_unlock+0x4d/0x230 kernel/locking/spinlock_debug.c:140
__raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_unlock+0x1e/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
filemap_remove_folio+0x1ae/0x2c0 mm/filemap.c:261
truncate_inode_folio+0x5d/0x70 mm/truncate.c:195
shmem_undo_range+0x3b9/0x1a40 mm/shmem.c:1023
shmem_truncate_range mm/shmem.c:1136 [inline]
shmem_evict_inode+0x273/0xa70 mm/shmem.c:1265
evict+0x486/0x870 fs/inode.c:705
__dentry_kill+0x431/0x650 fs/dcache.c:611
dentry_kill+0xb8/0x290 fs/dcache.c:-1
dput+0xfe/0x1e0 fs/dcache.c:918
__fput+0x5e5/0x970 fs/file_table.c:392
task_work_run+0x1ce/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2b4cb8fc57
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd30e32dd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f2b4cc10925 RCX: 00007f2b4cb8fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd30e32e90
RBP: 00007ffd30e32e90 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd30e33f20
R13: 00007f2b4cc10925 R14: 000000000006eafd R15: 00007ffd30e33f60
----------------
Code disassembly (best guess), 3 bytes skipped:
0: df 4d 8d fisttps -0x73(%rbp)
3: 34 19 xor $0x19,%al
5: 4d 89 f4 mov %r14,%r12
8: 4d 29 dc sub %r11,%r12
b: 49 83 fc 10 cmp $0x10,%r12
f: 7f 29 jg 0x3a
11: 4d 85 e4 test %r12,%r12
14: 0f 84 41 01 00 00 je 0x15b
1a: 4c 89 cb mov %r9,%rbx
1d: 48 f7 d3 not %rbx
20: 4c 01 fb add %r15,%rbx
23: 41 80 3b 00 cmpb $0x0,(%r11)
* 27: 0f 85 cc 01 00 00 jne 0x1f9 <-- trapping instruction
2d: 49 ff c3 inc %r11
30: 48 ff c3 inc %rbx
33: 75 ee jne 0x23
35: e9 21 01 00 00 jmp 0x15b
3a: 44 89 dd mov %r11d,%ebp