------------[ cut here ]------------
kernfs_put: syz2/pids.events: released with incorrect active_ref 0
WARNING: CPU: 0 PID: 6633 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540
------------[ cut here ]------------
Modules linked in:
WARNING: CPU: 1 PID: 8299 at fs/kernfs/dir.c:504 kernfs_get.part.0+0x69/0x80
Modules linked in:
CPU: 1 PID: 8299 Comm: syz-executor.5 Not tainted 5.19.0-rc4-next-20220701 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RIP: 0010:kernfs_get.part.0+0x69/0x80
Code: 31 ff 89 ee e8 a8 43 a7 ff 85 ed 74 18 e8 cf 46 a7 ff be 04 00 00 00 48 89 df e8 52 be d9 ff f0 ff 03 5b 5d c3 e8 b7 46 a7 ff <0f> 0b eb df 48 89 df e8 fb ba d9 ff eb c6 66 0f 1f 84 00 00 00 00
RSP: 0018:ffff88806cf09c80 EFLAGS: 00010046
CPU: 0 PID: 6633 Comm: kworker/0:0 Not tainted 5.19.0-rc4-next-20220701 #1
RAX: 0000000000000000 RBX: ffff88801d02f9f8 RCX: 0000000000000100
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RDX: ffff888046441ac0 RSI: ffffffff819d2579 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
Workqueue: events kernfs_notify_workfn
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001
R13: 1ffffffff0a01e40 R14: ffff88801d02f9f8 R15: ffff888044f1bd30
FS: 00007fa776fac700(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa779a89e10 CR3: 00000000175d8000 CR4: 0000000000350ee0
Call Trace:
kernfs_get+0x1b/0x30
RIP: 0010:kernfs_put.part.0+0x433/0x540
kernfs_notify+0x180/0x350
Code: 03 80 3c 18 00 0f 85 ea 00 00 00 4d 8b 7d 38 e8 53 42 a7 ff 48 8b 14 24 44 89 f1 4c 89 fe 48 c7 c7 a0 58 72 84 e8 97 1c 6c 02 <0f> 0b e9 b9 fc ff ff 48 89 ef e8 8e b6 d9 ff e9 c1 fd ff ff e8 84
cgroup_file_notify+0xf5/0x1a0
RSP: 0018:ffff88804788fbd8 EFLAGS: 00010286
call_timer_fn+0x17d/0x5f0
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: ffff888046303580 RSI: ffffffff812b6848 RDI: ffffed1008f11f6d
__run_timers.part.0+0x65e/0xa50
RBP: ffff88801d02fa30 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88801d02f9f8
run_timer_softirq+0xae/0x1a0
R13: ffff88801b82b658 R14: 0000000000000000 R15: ffff888017f29578
__do_softirq+0x1c8/0x8cc
__irq_exit_rcu+0x113/0x170
FS: 0000000000000000(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
irq_exit_rcu+0x5/0x20
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
sysvec_apic_timer_interrupt+0x8e/0xc0
CR2: 00007fc096fed7e0 CR3: 000000004645a000 CR4: 0000000000350ef0
Call Trace:
asm_sysvec_apic_timer_interrupt+0x1b/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0x2e/0x50
Code: 48 83 c7 18 53 48 89 f3 48 8b 74 24 10 e8 1a 49 0e fd 48 89 ef e8 82 ca 0e fd 80 e7 02 74 06 e8 b8 6e 30 fd fb bf 01 00 00 00 2d ad 04 fd 65 8b 05 d6 b3 e7 7b 85 c0 74 03 5b 5d c3 0f 1f 44
kernfs_put+0x42/0x50
RSP: 0018:ffff8880478bf6e8 EFLAGS: 00000206
kernfs_notify_workfn+0x417/0x560
RAX: 0000000000000739 RBX: 0000000000000246 RCX: ffffffff8128663f
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffffff852ca2a0 R08: 0000000000000001 R09: ffffffff86a5c827
R10: fffffbfff0d4b904 R11: 0000000000000001 R12: ffff8880080713c0
R13: 0000000000000cc0 R14: 0000000000000000 R15: ffff88801aa3ef00
process_one_work+0xa0f/0x1690
kmem_cache_alloc_lru+0x2e0/0x7e0
__d_alloc+0x31/0x990
worker_thread+0x637/0x1250
d_alloc_parallel+0x10a/0x1c00
kthread+0x2ed/0x3a0
ret_from_fork+0x22/0x30
lookup_open.isra.0+0x8f4/0x1270
irq event stamp: 256111
hardirqs last enabled at (256121): [] asm_sysvec_apic_timer_interrupt+0x1b/0x20
path_openat+0x99f/0x2890
hardirqs last disabled at (256132): [] sysvec_apic_timer_interrupt+0xb/0xc0
softirqs last enabled at (255712): [] __irq_exit_rcu+0x113/0x170
softirqs last disabled at (255627): [] __irq_exit_rcu+0x113/0x170
---[ end trace 0000000000000000 ]---
do_filp_open+0x1aa/0x400
==================================================================
BUG: KASAN: use-after-free in llist_del_first+0x89/0xa0
Read of size 8 at addr ffff88801d02fa78 by task kworker/0:0/6633
CPU: 0 PID: 6633 Comm: kworker/0:0 Tainted: G W 5.19.0-rc4-next-20220701 #1
do_sys_openat2+0x16d/0x4c0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Workqueue: events kernfs_notify_workfn
Call Trace:
__x64_sys_openat+0x13f/0x1f0
dump_stack_lvl+0x8b/0xb3
print_report.cold+0x5e/0x5e1
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x46/0xb0
kasan_report+0xb1/0x1b0
RIP: 0033:0x7fa779a36b19
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 bc ff ff ff f7 d8 64 89 01 48
llist_del_first+0x89/0xa0
RSP: 002b:00007fa776fac188 EFLAGS: 00000246
kernfs_notify_workfn+0x78/0x560
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa779b49f60 RCX: 00007fa779a36b19
RDX: 0000000000000000 RSI: 0000000020000240 RDI: ffffffffffffff9c
process_one_work+0xa0f/0x1690
RBP: 00007fa779a90f6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc5f1b98ff R14: 00007fa776fac300 R15: 0000000000022000
worker_thread+0x637/0x1250
irq event stamp: 1865
hardirqs last enabled at (1864): [] asm_sysvec_apic_timer_interrupt+0x1b/0x20
hardirqs last disabled at (1865): [] _raw_spin_lock_irqsave+0x4e/0x50
softirqs last enabled at (1636): [] __irq_exit_rcu+0x113/0x170
kthread+0x2ed/0x3a0
softirqs last disabled at (1853): [] __irq_exit_rcu+0x113/0x170
---[ end trace 0000000000000000 ]---
ret_from_fork+0x22/0x30
Allocated by task 300:
kasan_save_stack+0x1e/0x40
__kasan_slab_alloc+0x66/0x80
kmem_cache_alloc+0x1b1/0x490
__kernfs_new_node+0xd4/0x8b0
kernfs_new_node+0x93/0x120
__kernfs_create_file+0x51/0x350
cgroup_addrm_files+0x3e2/0x9d0
css_populate_dir+0x19b/0x450
cgroup_apply_control_enable+0x3ae/0xa40
cgroup_mkdir+0x824/0x11f0
kernfs_iop_mkdir+0x149/0x1d0
vfs_mkdir+0x417/0x6a0
do_mkdirat+0x17b/0x2e0
__x64_sys_mkdir+0xf2/0x140
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x46/0xb0
Freed by task 6633:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
kasan_set_free_info+0x20/0x30
__kasan_slab_free+0x108/0x190
kmem_cache_free+0xfb/0x600
kernfs_put.part.0+0x2c7/0x540
kernfs_put+0x42/0x50
kernfs_notify_workfn+0x417/0x560
process_one_work+0xa0f/0x1690
worker_thread+0x637/0x1250
kthread+0x2ed/0x3a0
ret_from_fork+0x22/0x30
The buggy address belongs to the object at ffff88801d02f9f8
which belongs to the cache kernfs_node_cache of size 168
The buggy address is located 128 bytes inside of
168-byte region [ffff88801d02f9f8, ffff88801d02faa0)
The buggy address belongs to the physical page:
page:00000000b9086b91 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d02f
flags: 0x100000000000200(slab|node=0|zone=1)
raw: 0100000000000200 0000000000000000 dead000000000122 ffff8880080718c0
raw: 0000000000000000 0000000000110011 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88801d02f900: fc fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88801d02f980: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fa
>ffff88801d02fa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88801d02fa80: fb fb fb fb fc fc fc fc fc fc fc fc 00 00 00 00
ffff88801d02fb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: 48 83 c7 18 add $0x18,%rdi
4: 53 push %rbx
5: 48 89 f3 mov %rsi,%rbx
8: 48 8b 74 24 10 mov 0x10(%rsp),%rsi
d: e8 1a 49 0e fd callq 0xfd0e492c
12: 48 89 ef mov %rbp,%rdi
15: e8 82 ca 0e fd callq 0xfd0eca9c
1a: 80 e7 02 and $0x2,%bh
1d: 74 06 je 0x25
1f: e8 b8 6e 30 fd callq 0xfd306edc
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 2d ad 04 fd callq 0xfd04ad5c <-- trapping instruction
2f: 65 8b 05 d6 b3 e7 7b mov %gs:0x7be7b3d6(%rip),%eax # 0x7be7b40c
36: 85 c0 test %eax,%eax
38: 74 03 je 0x3d
3a: 5b pop %rbx
3b: 5d pop %rbp
3c: c3 retq
3d: 0f .byte 0xf
3e: 1f (bad)
3f: 44 rex.R