------------[ cut here ]------------
kernfs_put: syz0/pids.events: released with incorrect active_ref 0
------------[ cut here ]------------
WARNING: CPU: 0 PID: 12 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540
WARNING: CPU: 1 PID: 11517 at fs/kernfs/dir.c:504 kernfs_get.part.0+0x69/0x80
Modules linked in:
Modules linked in:
CPU: 1 PID: 11517 Comm: syz-executor.7 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
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.19.0-rc5-next-20220706 #1
RIP: 0010:kernfs_get.part.0+0x69/0x80
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
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
Workqueue: events kernfs_notify_workfn
RAX: 0000000000000000 RBX: ffff888043d12cb0 RCX: 0000000000000100
RDX: ffff888049861ac0 RSI: ffffffff819df849 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
RIP: 0010:kernfs_put.part.0+0x433/0x540
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001
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
R13: 1ffffffff0a01e40 R14: ffff888043d12cb0 R15: ffff88800e696930
FS: 00007f46a10de700(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
RSP: 0018:ffff88800824fbd8 EFLAGS: 00010286
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555ecc809398 CR3: 000000004a4be000 CR4: 0000000000350ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
Call Trace:
kernfs_get+0x1b/0x30
RDX: ffff88800822d040 RSI: ffffffff812bd348 RDI: ffffed1001049f6d
kernfs_notify+0x180/0x350
RBP: ffff888043d12ce8 R08: 0000000000000005 R09: 0000000000000000
cgroup_file_notify+0xf5/0x1a0
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888043d12cb0
R13: ffff88801a7cd910 R14: 0000000000000000 R15: ffff88800f11beb0
call_timer_fn+0x17d/0x5f0
FS: 0000000000000000(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020001000 CR3: 0000000048672000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
__run_timers.part.0+0x65e/0xa50
Call Trace:
kernfs_put+0x42/0x50
kernfs_notify_workfn+0x417/0x560
run_timer_softirq+0xae/0x1a0
__do_softirq+0x1c8/0x8cc
__irq_exit_rcu+0x113/0x170
irq_exit_rcu+0x5/0x20
process_one_work+0xa0f/0x1690
sysvec_apic_timer_interrupt+0x8e/0xc0
asm_sysvec_apic_timer_interrupt+0x1b/0x20
RIP: 0010:finish_task_switch.isra.0+0x23a/0x8a0
Code: 89 f7 48 c7 03 00 00 00 00 e8 a2 54 20 03 4d 85 e4 75 ba 4c 89 f7 e8 e5 38 fc 02 e8 a0 e2 2b 00 fb 65 48 8b 1c 25 c0 6e 02 00 <48> 8d bb 10 14 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffff88804a6a7b90 EFLAGS: 00000206
RAX: 0000000000006855 RBX: ffff888049861ac0 RCX: 1ffffffff0b1cf69
worker_thread+0x637/0x1250
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88804a6a7bd0 R08: 0000000000000001 R09: 0000000000000001
R10: ffffed100d9e6fa0 R11: 0000000000000001 R12: ffff88806cf37d18
R13: ffff88801aa28000 R14: ffff88806cf37d00 R15: ffff88806cf386f8
kthread+0x2ed/0x3a0
__schedule+0x89b/0x24a0
ret_from_fork+0x22/0x30
irq event stamp: 2793669
preempt_schedule_common+0x45/0xc0
hardirqs last enabled at (2793679): [] console_emit_next_record.constprop.0+0x648/0x800
__cond_resched+0x13/0x20
hardirqs last disabled at (2793690): [] sysvec_apic_timer_interrupt+0xb/0xc0
__sys_sendmmsg+0x230/0x470
softirqs last enabled at (2789128): [] __irq_exit_rcu+0x113/0x170
softirqs last disabled at (2789123): [] __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 ffff888043d12d30 by task kworker/0:1/12
CPU: 0 PID: 12 Comm: kworker/0:1 Tainted: G W 5.19.0-rc5-next-20220706 #1
__x64_sys_sendmmsg+0x99/0x100
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
do_syscall_64+0x3b/0x90
Call Trace:
entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f46a3b68b19
dump_stack_lvl+0x8b/0xb3
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
print_report.cold+0x5e/0x5e1
RSP: 002b:00007f46a10de188 EFLAGS: 00000246
ORIG_RAX: 0000000000000133
kasan_report+0xb1/0x1b0
RAX: ffffffffffffffda RBX: 00007f46a3c7bf60 RCX: 00007f46a3b68b19
RDX: 0000000004000101 RSI: 0000000020002880 RDI: 0000000000000006
llist_del_first+0x89/0xa0
RBP: 00007f46a3bc2f6d R08: 0000000000000000 R09: 0000000000000000
kernfs_notify_workfn+0x78/0x560
R10: 0000000000200000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe340565ef R14: 00007f46a10de300 R15: 0000000000022000
irq event stamp: 26747
process_one_work+0xa0f/0x1690
hardirqs last enabled at (26746): [] asm_sysvec_apic_timer_interrupt+0x1b/0x20
hardirqs last disabled at (26747): [] _raw_spin_lock_irqsave+0x4e/0x50
softirqs last enabled at (26706): [] do_softirq.part.0+0xcd/0x110
softirqs last disabled at (26725): [] __irq_exit_rcu+0x113/0x170
worker_thread+0x637/0x1250
---[ end trace 0000000000000000 ]---
kthread+0x2ed/0x3a0
ret_from_fork+0x22/0x30
Allocated by task 302:
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 12:
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 ffff888043d12cb0
which belongs to the cache kernfs_node_cache of size 168
The buggy address is located 128 bytes inside of
168-byte region [ffff888043d12cb0, ffff888043d12d58)
The buggy address belongs to the physical page:
page:000000005e099209 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x43d12
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:
ffff888043d12c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc
ffff888043d12c80: fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb
>ffff888043d12d00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
^
ffff888043d12d80: fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888043d12e00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
0: 89 f7 mov %esi,%edi
2: 48 c7 03 00 00 00 00 movq $0x0,(%rbx)
9: e8 a2 54 20 03 callq 0x32054b0
e: 4d 85 e4 test %r12,%r12
11: 75 ba jne 0xffffffcd
13: 4c 89 f7 mov %r14,%rdi
16: e8 e5 38 fc 02 callq 0x2fc3900
1b: e8 a0 e2 2b 00 callq 0x2be2c0
20: fb sti
21: 65 48 8b 1c 25 c0 6e mov %gs:0x26ec0,%rbx
28: 02 00
* 2a: 48 8d bb 10 14 00 00 lea 0x1410(%rbx),%rdi <-- trapping instruction
31: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
38: fc ff df
3b: 48 89 fa mov %rdi,%rdx
3e: 48 rex.W
3f: c1 .byte 0xc1