------------[ cut here ]------------
kernfs_put: syz7/pids.events: released with incorrect active_ref 0
WARNING: CPU: 1 PID: 4854 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540
Modules linked in:
CPU: 1 PID: 4854 Comm: kworker/1:0 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
Workqueue: events kernfs_notify_workfn
RIP: 0010:kernfs_put.part.0+0x433/0x540
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
------------[ cut here ]------------
RSP: 0018:ffff888044ddfbd8 EFLAGS: 00010286
WARNING: CPU: 0 PID: 296 at fs/kernfs/dir.c:504 kernfs_get.part.0+0x69/0x80
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
Modules linked in:
CPU: 0 PID: 296 Comm: syz-executor.2 Not tainted 5.19.0-rc4-next-20220701 #1
RDX: ffff8880451f0000 RSI: ffffffff812b6848 RDI: ffffed10089bbf6d
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
RBP: ffff88801579feb8 R08: 0000000000000005 R09: 0000000000000000
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:ffff88806ce09c80 EFLAGS: 00010046
R10: 0000000080000000 R11: 0000000000000001 R12: ffff88801579fe80
RAX: 0000000000000000 RBX: ffff88801579fe80 RCX: 0000000000000100
R13: ffff88801d1d4ae0 R14: 0000000000000000 R15: ffff888014c21ca8
RDX: ffff88800eac9ac0 RSI: ffffffff819d2579 RDI: 0000000000000005
FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
R13: 1ffffffff0a01e40 R14: ffff88801579fe80 R15: ffff88800e89b130
CR2: 00005555570c1708 CR3: 0000000047e06000 CR4: 0000000000350ee0
FS: 0000555556859400(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
CR2: 00007fe17ac11dc8 CR3: 000000001783c000 CR4: 0000000000350ef0
Call Trace:
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
Call Trace:
kernfs_put+0x42/0x50
kernfs_get+0x1b/0x30
kernfs_notify_workfn+0x417/0x560
kernfs_notify+0x180/0x350
cgroup_file_notify+0xf5/0x1a0
call_timer_fn+0x17d/0x5f0
process_one_work+0xa0f/0x1690
worker_thread+0x637/0x1250
__run_timers.part.0+0x65e/0xa50
kthread+0x2ed/0x3a0
ret_from_fork+0x22/0x30
run_timer_softirq+0xae/0x1a0
irq event stamp: 180679
__do_softirq+0x1c8/0x8cc
hardirqs last enabled at (180689): [] asm_sysvec_apic_timer_interrupt+0x1b/0x20
__irq_exit_rcu+0x113/0x170
hardirqs last disabled at (180698): [] sysvec_apic_timer_interrupt+0xb/0xc0
irq_exit_rcu+0x5/0x20
softirqs last enabled at (179836): [] process_one_work+0xa0f/0x1690
sysvec_apic_timer_interrupt+0x8e/0xc0
softirqs last disabled at (179832): [] neigh_periodic_work+0x62/0x9f0
---[ end trace 0000000000000000 ]---
==================================================================
asm_sysvec_apic_timer_interrupt+0x1b/0x20
BUG: KASAN: use-after-free in llist_del_first+0x89/0xa0
RIP: 0010:do_wait+0x72d/0xc70
Read of size 8 at addr ffff88801579ff00 by task kworker/1:0/4854
Code: f8 48 c1 e8 03 42 80 3c 20 00 0f 85 ae 03 00 00 49 8b 85 58 05 00 00 48 8d 98 98 fa ff ff 49 39 c7 75 33 eb 61 e8 03 7d 2e 00 <48> 8d bb 68 05 00 00 48 89 f8 48 c1 e8 03 42 80 3c 20 00 0f 85 71
CPU: 1 PID: 4854 Comm: kworker/1:0 Tainted: G W 5.19.0-rc4-next-20220701 #1
RSP: 0018:ffff88801b937c90 EFLAGS: 00000293
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
RAX: 0000000000000000 RBX: ffff8880468c1ac0 RCX: 0000000000000000
Call Trace:
RDX: ffff88800eac9ac0 RSI: ffffffff8115ef2d RDI: 0000000000000005
dump_stack_lvl+0x8b/0xb3
RBP: ffff88801b937d18 R08: 0000000000000005 R09: 0000000000000000
print_report.cold+0x5e/0x5e1
R10: 0000000000000000 R11: 0000000000000001 R12: dffffc0000000000
R13: ffff88800eac9ac0 R14: 0000000000000000 R15: ffff88800eaca018
kasan_report+0xb1/0x1b0
kernel_wait4+0x14c/0x260
llist_del_first+0x89/0xa0
kernfs_notify_workfn+0x78/0x560
__do_sys_wait4+0x13f/0x150
process_one_work+0xa0f/0x1690
worker_thread+0x637/0x1250
kthread+0x2ed/0x3a0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x46/0xb0
ret_from_fork+0x22/0x30
RIP: 0033:0x7f396bbc8fb7
Code: 89 7c 24 10 48 89 4c 24 18 e8 d5 50 02 00 4c 8b 54 24 18 8b 54 24 14 41 89 c0 48 8b 74 24 08 8b 7c 24 10 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 89 44 24 10 e8 05 51 02 00 8b 44
Allocated by task 299:
RSP: 002b:00007fff494cba20 EFLAGS: 00000293
kasan_save_stack+0x1e/0x40
ORIG_RAX: 000000000000003d
__kasan_slab_alloc+0x66/0x80
RAX: ffffffffffffffda RBX: 0000000000000188 RCX: 00007f396bbc8fb7
kmem_cache_alloc+0x1b1/0x490
RDX: 0000000040000001 RSI: 00007fff494cbaac RDI: 00000000ffffffff
__kernfs_new_node+0xd4/0x8b0
RBP: 00007fff494cbaac R08: 0000000000000000 R09: 00007fff495db080
kernfs_new_node+0x93/0x120
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032
__kernfs_create_file+0x51/0x350
R13: 00000000000d4daa R14: 000000000000000f R15: 00007fff494cbb10
cgroup_addrm_files+0x3e2/0x9d0
css_populate_dir+0x19b/0x450
irq event stamp: 1306395
cgroup_apply_control_enable+0x3ae/0xa40
hardirqs last enabled at (1306394): [] _raw_spin_unlock_irq+0x1f/0x40
cgroup_mkdir+0x824/0x11f0
hardirqs last disabled at (1306395): [] _raw_spin_lock_irqsave+0x4e/0x50
kernfs_iop_mkdir+0x149/0x1d0
softirqs last enabled at (1305808): [] __irq_exit_rcu+0x113/0x170
vfs_mkdir+0x417/0x6a0
softirqs last disabled at (1306391): [] __irq_exit_rcu+0x113/0x170
do_mkdirat+0x17b/0x2e0
---[ end trace 0000000000000000 ]---
__x64_sys_mkdir+0xf2/0x140
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x46/0xb0
Freed by task 4854:
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 ffff88801579fe80
which belongs to the cache kernfs_node_cache of size 168
The buggy address is located 128 bytes inside of
168-byte region [ffff88801579fe80, ffff88801579ff28)
The buggy address belongs to the physical page:
page:00000000df81d3d1 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1579f
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:
ffff88801579fe00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
ffff88801579fe80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801579ff00: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
^
ffff88801579ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880157a0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: f8 clc
1: 48 c1 e8 03 shr $0x3,%rax
5: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1)
a: 0f 85 ae 03 00 00 jne 0x3be
10: 49 8b 85 58 05 00 00 mov 0x558(%r13),%rax
17: 48 8d 98 98 fa ff ff lea -0x568(%rax),%rbx
1e: 49 39 c7 cmp %rax,%r15
21: 75 33 jne 0x56
23: eb 61 jmp 0x86
25: e8 03 7d 2e 00 callq 0x2e7d2d
* 2a: 48 8d bb 68 05 00 00 lea 0x568(%rbx),%rdi <-- trapping instruction
31: 48 89 f8 mov %rdi,%rax
34: 48 c1 e8 03 shr $0x3,%rax
38: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1)
3d: 0f .byte 0xf
3e: 85 .byte 0x85
3f: 71 .byte 0x71