------------[ cut here ]------------
kernfs_put: syz4/pids.events: released with incorrect active_ref 0
WARNING: CPU: 1 PID: 20 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540
Modules linked in:
CPU: 1 PID: 20 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
RSP: 0018:ffff8880082c7bd8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: ffff8880082b8000 RSI: ffffffff812b6848 RDI: ffffed1001058f6d
RBP: ffff88800e656690 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000001 R12: ffff88800e656658
R13: ffff88800e3fc9f8 R14: 0000000000000000 R15: ffff88800df54cf8
FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5079e80d60 CR3: 0000000045ec8000 CR4: 0000000000350ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
Call Trace:
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
irq event stamp: 588905
hardirqs last enabled at (588915): [] __up_console_sem+0x78/0x80
hardirqs last disabled at (588926): [] __up_console_sem+0x5d/0x80
softirqs last enabled at (588532): [] __irq_exit_rcu+0x113/0x170
softirqs last disabled at (588467): [] __irq_exit_rcu+0x113/0x170
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: use-after-free in llist_del_first+0x89/0xa0
Read of size 8 at addr ffff88800e6566d8 by task kworker/1:0/20
CPU: 1 PID: 20 Comm: kworker/1:0 Tainted: G W 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
Call Trace:
dump_stack_lvl+0x8b/0xb3
print_report.cold+0x5e/0x5e1
kasan_report+0xb1/0x1b0
llist_del_first+0x89/0xa0
kernfs_notify_workfn+0x78/0x560
------------[ cut here ]------------
process_one_work+0xa0f/0x1690
WARNING: CPU: 0 PID: 10056 at fs/kernfs/dir.c:504 kernfs_get.part.0+0x69/0x80
Modules linked in:
worker_thread+0x637/0x1250
CPU: 0 PID: 10056 Comm: syz-executor.4 Tainted: G W 5.19.0-rc4-next-20220701 #1
kthread+0x2ed/0x3a0
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
ret_from_fork+0x22/0x30
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:ffff88804735fa40 EFLAGS: 00010093
Allocated by task 297:
kasan_save_stack+0x1e/0x40
RAX: 0000000000000000 RBX: ffff88800e656658 RCX: 0000000000000000
__kasan_slab_alloc+0x66/0x80
RDX: ffff888045a33580 RSI: ffffffff819d2579 RDI: 0000000000000005
kmem_cache_alloc+0x1b1/0x490
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
__kernfs_new_node+0xd4/0x8b0
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001
kernfs_new_node+0x93/0x120
R13: 1ffffffff0a01e40 R14: ffff88800e656658 R15: ffff88800cc7e530
__kernfs_create_file+0x51/0x350
FS: 0000555555c11400(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
cgroup_addrm_files+0x3e2/0x9d0
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
css_populate_dir+0x19b/0x450
CR2: 00007fd64d69a718 CR3: 0000000044f4a000 CR4: 0000000000350ef0
cgroup_apply_control_enable+0x3ae/0xa40
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
cgroup_mkdir+0x824/0x11f0
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
kernfs_iop_mkdir+0x149/0x1d0
Call Trace:
vfs_mkdir+0x417/0x6a0
do_mkdirat+0x17b/0x2e0
kernfs_get+0x1b/0x30
__x64_sys_mkdir+0xf2/0x140
kernfs_notify+0x180/0x350
do_syscall_64+0x3b/0x90
cgroup_file_notify+0xf5/0x1a0
entry_SYSCALL_64_after_hwframe+0x46/0xb0
pids_can_fork+0x22f/0x370
Freed by task 20:
kasan_save_stack+0x1e/0x40
cgroup_can_fork+0x332/0x11b0
kasan_set_track+0x21/0x30
copy_process+0x4023/0x6d60
kasan_set_free_info+0x20/0x30
__kasan_slab_free+0x108/0x190
kernel_clone+0xe7/0xa60
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
__do_sys_clone+0xba/0x100
worker_thread+0x637/0x1250
kthread+0x2ed/0x3a0
ret_from_fork+0x22/0x30
The buggy address belongs to the object at ffff88800e656658
which belongs to the cache kernfs_node_cache of size 168
do_syscall_64+0x3b/0x90
The buggy address is located 128 bytes inside of
168-byte region [ffff88800e656658, ffff88800e656700)
entry_SYSCALL_64_after_hwframe+0x46/0xb0
The buggy address belongs to the physical page:
RIP: 0033:0x7f7058becf41
page:00000000e1e486cc refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xe656
Code: 48 85 ff 74 3d 48 85 f6 74 38 48 83 ee 10 48 89 4e 08 48 89 3e 48 89 d7 4c 89 c2 4d 89 c8 4c 8b 54 24 08 b8 38 00 00 00 0f 05 <48> 85 c0 7c 13 74 01 c3 31 ed 58 5f ff d0 48 89 c7 b8 3c 00 00 00
flags: 0x100000000000200(slab|node=0|zone=1)
RSP: 002b:00007ffc70e7c958 EFLAGS: 00000206
raw: 0100000000000200 0000000000000000 dead000000000001 ffff8880080718c0
ORIG_RAX: 0000000000000038
raw: 0000000000000000 0000000000110011 00000001ffffffff 0000000000000000
RAX: ffffffffffffffda RBX: 00007f7056140700 RCX: 00007f7058becf41
page dumped because: kasan: bad access detected
RDX: 00007f70561409d0 RSI: 00007f70561402f0 RDI: 00000000003d0f00
Memory state around the buggy address:
RBP: 00007ffc70e7cb90 R08: 00007f7056140700 R09: 00007f7056140700
ffff88800e656580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
R10: 00007f70561409d0 R11: 0000000000000206 R12: 00007ffc70e7ca0e
ffff88800e656600: 00 00 00 fc fc fc fc fc fc fc fc fa fb fb fb fb
R13: 00007ffc70e7ca0f R14: 00007f7056140300 R15: 0000555555c12d50
>ffff88800e656680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
irq event stamp: 4626
ffff88800e656700: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
hardirqs last enabled at (4625): [] _raw_spin_unlock_irq+0x1f/0x40
ffff88800e656780: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc
hardirqs last disabled at (4626): [] _raw_spin_lock_irqsave+0x4e/0x50
==================================================================
softirqs last enabled at (4604): [] fpu_clone+0x3be/0xb00
softirqs last disabled at (4602): [] fpu_clone+0x331/0xb00
---[ end trace 0000000000000000 ]---
kmemleak: 9 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
----------------
Code disassembly (best guess):
0: 48 85 ff test %rdi,%rdi
3: 74 3d je 0x42
5: 48 85 f6 test %rsi,%rsi
8: 74 38 je 0x42
a: 48 83 ee 10 sub $0x10,%rsi
e: 48 89 4e 08 mov %rcx,0x8(%rsi)
12: 48 89 3e mov %rdi,(%rsi)
15: 48 89 d7 mov %rdx,%rdi
18: 4c 89 c2 mov %r8,%rdx
1b: 4d 89 c8 mov %r9,%r8
1e: 4c 8b 54 24 08 mov 0x8(%rsp),%r10
23: b8 38 00 00 00 mov $0x38,%eax
28: 0f 05 syscall
* 2a: 48 85 c0 test %rax,%rax <-- trapping instruction
2d: 7c 13 jl 0x42
2f: 74 01 je 0x32
31: c3 retq
32: 31 ed xor %ebp,%ebp
34: 58 pop %rax
35: 5f pop %rdi
36: ff d0 callq *%rax
38: 48 89 c7 mov %rax,%rdi
3b: b8 3c 00 00 00 mov $0x3c,%eax