------------[ cut here ]------------
kernfs_put: syz3/pids.events: released with incorrect active_ref 0
WARNING: CPU: 0 PID: 8484 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540
------------[ cut here ]------------
Modules linked in:
WARNING: CPU: 1 PID: 9652 at fs/kernfs/dir.c:504 kernfs_get.part.0+0x69/0x80
Modules linked in:
CPU: 0 PID: 8484 Comm: kworker/0:0 Not tainted 5.19.0-rc5-next-20220706 #1
CPU: 1 PID: 9652 Comm: syz-executor.3 Not tainted 5.19.0-rc5-next-20220706 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
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_get.part.0+0x69/0x80
Code: 31 ff 89 ee e8 a8 fd a6 ff 85 ed 74 18 e8 cf 00 a7 ff be 04 00 00 00 48 89 df e8 d2 ba d9 ff f0 ff 03 5b 5d c3 e8 b7 00 a7 ff <0f> 0b eb df 48 89 df e8 7b b7 d9 ff eb c6 66 0f 1f 84 00 00 00 00
RSP: 0018:ffff88806cf09c80 EFLAGS: 00010046
RIP: 0010:kernfs_put.part.0+0x433/0x540
RAX: 0000000000000000 RBX: ffff88800db3f570 RCX: 0000000000000100
Code: 03 80 3c 18 00 0f 85 ea 00 00 00 4d 8b 7d 38 e8 53 fc a6 ff 48 8b 14 24 44 89 f1 4c 89 fe 48 c7 c7 e0 5b 72 84 e8 13 aa 6c 02 <0f> 0b e9 b9 fc ff ff 48 89 ef e8 0e b3 d9 ff e9 c1 fd ff ff e8 04
RDX: ffff88804a6a0000 RSI: ffffffff819df849 RDI: 0000000000000005
RSP: 0018:ffff888044d67bd8 EFLAGS: 00010286
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001
R13: 1ffffffff0a01e40 R14: ffff88800db3f570 R15: ffff88801e92e930
FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe09688a10 CR3: 0000000005026000 CR4: 0000000000350ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
Call Trace:
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
kernfs_get+0x1b/0x30
RDX: ffff88800f9d1ac0 RSI: ffffffff812bd348 RDI: ffffed10089acf6d
kernfs_notify+0x180/0x350
RBP: ffff88800db3f5a8 R08: 0000000000000005 R09: 0000000000000000
cgroup_file_notify+0xf5/0x1a0
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800db3f570
call_timer_fn+0x17d/0x5f0
R13: ffff88801e9a31d0 R14: 0000000000000000 R15: ffff888008fea258
FS: 0000000000000000(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
__run_timers.part.0+0x65e/0xa50
CR2: 0000001b2d832000 CR3: 00000000458f0000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
run_timer_softirq+0xae/0x1a0
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
__do_softirq+0x1c8/0x8cc
Call Trace:
__irq_exit_rcu+0x113/0x170
irq_exit_rcu+0x5/0x20
sysvec_apic_timer_interrupt+0x8e/0xc0
kernfs_put+0x42/0x50
kernfs_notify_workfn+0x417/0x560
asm_sysvec_apic_timer_interrupt+0x1b/0x20
RIP: 0010:lock_release+0x3dd/0x750
Code: ff ff ff ff 65 0f c1 05 49 05 d9 7e 83 f8 01 0f 85 ad 01 00 00 48 f7 04 24 00 02 00 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c5 48 c7 45 00 00 00 00 00 c7 45 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffff888043c6f838 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 8732d17692d9d6e8 RCX: ffff888043c6f888
RDX: 1ffff110094d412d RSI: 0000000000000001 RDI: 0000000000000000
process_one_work+0xa0f/0x1690
RBP: 1ffff1100878df09 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000002
R13: 0000000000000003 R14: ffff88804a6a0970 R15: ffff88804a6a0000
worker_thread+0x637/0x1250
page_remove_rmap+0xfa/0x490
unmap_page_range+0xe8f/0x2720
kthread+0x2ed/0x3a0
unmap_single_vma+0x190/0x350
unmap_vmas+0x21e/0x370
ret_from_fork+0x22/0x30
exit_mmap+0x154/0x680
irq event stamp: 51083
hardirqs last enabled at (51093): [] asm_sysvec_apic_timer_interrupt+0x1b/0x20
hardirqs last disabled at (51102): [] sysvec_apic_timer_interrupt+0xb/0xc0
mmput+0xd1/0x390
softirqs last enabled at (50574): [] srcu_invoke_callbacks+0x1e5/0x3a0
do_exit+0xa01/0x27d0
softirqs last disabled at (50570): [] srcu_invoke_callbacks+0x1b5/0x3a0
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: use-after-free in llist_del_first+0x89/0xa0
Read of size 8 at addr ffff88800db3f5f0 by task kworker/0:0/8484
do_group_exit+0xd2/0x2f0
__x64_sys_exit_group+0x3a/0x50
CPU: 0 PID: 8484 Comm: kworker/0:0 Tainted: G W 5.19.0-rc5-next-20220706 #1
do_syscall_64+0x3b/0x90
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
entry_SYSCALL_64_after_hwframe+0x46/0xb0
Workqueue: events kernfs_notify_workfn
RIP: 0033:0x7fdc9e0f5b19
Code: Unable to access opcode bytes at RIP 0x7fdc9e0f5aef.
Call Trace:
RSP: 002b:00007ffe0968afa8 EFLAGS: 00000246
ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fdc9e20902c RCX: 00007fdc9e0f5b19
dump_stack_lvl+0x8b/0xb3
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
print_report.cold+0x5e/0x5e1
RBP: 00007fdc9e14f259 R08: 000000000000000c R09: 00007fdc9e208f60
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000b
kasan_report+0xb1/0x1b0
R13: 00007ffe0968b1c0 R14: 00007fdc9e208f60 R15: 0000000000000001
llist_del_first+0x89/0xa0
irq event stamp: 13219
hardirqs last enabled at (13218): [] _raw_spin_unlock_irq+0x1f/0x40
kernfs_notify_workfn+0x78/0x560
hardirqs last disabled at (13219): [] _raw_spin_lock_irqsave+0x4e/0x50
softirqs last enabled at (13076): [] fpu_clone+0x3be/0xb00
softirqs last disabled at (13215): [] __irq_exit_rcu+0x113/0x170
process_one_work+0xa0f/0x1690
---[ end trace 0000000000000000 ]---
worker_thread+0x637/0x1250
kthread+0x2ed/0x3a0
ret_from_fork+0x22/0x30
Allocated by task 293:
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 8484:
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 ffff88800db3f570
which belongs to the cache kernfs_node_cache of size 168
The buggy address is located 128 bytes inside of
168-byte region [ffff88800db3f570, ffff88800db3f618)
The buggy address belongs to the physical page:
page:000000008e26f215 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xdb3f
flags: 0x100000000000200(slab|node=0|zone=1)
raw: 0100000000000200 0000000000000000 dead000000000122 ffff8880080358c0
raw: 0000000000000000 0000000000110011 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88800db3f480: fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88800db3f500: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fa fb
>ffff88800db3f580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88800db3f600: fb fb fb fc fc fc fc fc fc fc fc 00 00 00 00 00
ffff88800db3f680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess), 3 bytes skipped:
0: ff 65 0f jmpq *0xf(%rbp)
3: c1 05 49 05 d9 7e 83 roll $0x83,0x7ed90549(%rip) # 0x7ed90553
a: f8 clc
b: 01 0f add %ecx,(%rdi)
d: 85 ad 01 00 00 48 test %ebp,0x48000001(%rbp)
13: f7 04 24 00 02 00 00 testl $0x200,(%rsp)
1a: 74 01 je 0x1d
1c: fb sti
1d: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
24: fc ff df
* 27: 48 01 c5 add %rax,%rbp <-- trapping instruction
2a: 48 c7 45 00 00 00 00 movq $0x0,0x0(%rbp)
31: 00
32: c7 45 08 00 00 00 00 movl $0x0,0x8(%rbp)
39: 48 rex.W
3a: 8b .byte 0x8b
3b: 84 .byte 0x84
3c: 24 .byte 0x24