------------[ cut here ]------------
kernfs_put: syz4/memory.events: released with incorrect active_ref 0
WARNING: CPU: 1 PID: 84 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540
Modules linked in:
CPU: 1 PID: 84 Comm: kworker/1:3 Not tainted 5.19.0-rc4-next-20220704 #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 73 0b a7 ff 48 8b 14 24 44 89 f1 4c 89 fe 48 c7 c7 e0 58 72 84 e8 93 9c 6c 02 <0f> 0b e9 b9 fc ff ff 48 89 ef e8 0e b3 d9 ff e9 c1 fd ff ff e8 04
RSP: 0018:ffff88800fa7fbd8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: ffff88800fa69ac0 RSI: ffffffff812bd348 RDI: ffffed1001f4ff6d
RBP: ffff88801541b2f0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88801541b2b8
R13: ffff88800f566570 R14: 0000000000000000 R15: ffff8880091e7118
FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1383bb8718 CR3: 0000000005026000 CR4: 0000000000350ee0
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: 487709
hardirqs last enabled at (487719): [] __up_console_sem+0x78/0x80
hardirqs last disabled at (487730): [] __up_console_sem+0x5d/0x80
softirqs last enabled at (487304): [] __irq_exit_rcu+0x113/0x170
softirqs last disabled at (487097): [] __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 ffff88801541b338 by task kworker/1:3/84
CPU: 1 PID: 84 Comm: kworker/1:3 Tainted: G W 5.19.0-rc4-next-20220704 #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
process_one_work+0xa0f/0x1690
worker_thread+0x637/0x1250
kthread+0x2ed/0x3a0
ret_from_fork+0x22/0x30
Allocated by task 295:
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 84:
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 ffff88801541b2b8
which belongs to the cache kernfs_node_cache of size 168
The buggy address is located 128 bytes inside of
168-byte region [ffff88801541b2b8, ffff88801541b360)
The buggy address belongs to the physical page:
page:000000007bfb16f8 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1541b
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:
ffff88801541b200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc
ffff88801541b280: fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb
>ffff88801541b300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff88801541b380: fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00
ffff88801541b400: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
==================================================================
tmpfs: Bad value for 'mpol'
tmpfs: Bad value for 'mpol'
__nla_validate_parse: 3 callbacks suppressed
netlink: 2552 bytes leftover after parsing attributes in process `syz-executor.4'.