------------[ cut here ]------------ kernfs_put: syz5/pids.events: released with incorrect active_ref 0 WARNING: CPU: 1 PID: 32 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540 Modules linked in: CPU: 1 PID: 32 Comm: kworker/1:1 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 ]------------ WARNING: CPU: 1 PID: 32 at fs/kernfs/dir.c:504 kernfs_get.part.0+0x69/0x80 Modules linked in: CPU: 1 PID: 32 Comm: kworker/1:1 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_get.part.0+0x69/0x80 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:ffff88806cf09c80 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff888036492bc8 RCX: 0000000000000100 RDX: ffff888008ec0000 RSI: ffffffff819d2579 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 1ffffffff0a01e40 R14: ffff888036492bc8 R15: ffff888037d13d30 FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7a88583368 CR3: 000000001d128000 CR4: 0000000000350ee0 Call Trace: kernfs_get+0x1b/0x30 kernfs_notify+0x180/0x350 cgroup_file_notify+0xf5/0x1a0 call_timer_fn+0x17d/0x5f0 __run_timers.part.0+0x65e/0xa50 run_timer_softirq+0xae/0x1a0 __do_softirq+0x1c8/0x8cc __irq_exit_rcu+0x113/0x170 irq_exit_rcu+0x5/0x20 sysvec_apic_timer_interrupt+0x8e/0xc0 asm_sysvec_apic_timer_interrupt+0x1b/0x20 RIP: 0010:console_emit_next_record.constprop.0+0x4c8/0x800 Code: 83 e2 07 38 d0 7f 08 84 c0 0f 85 d5 02 00 00 88 5d 00 e8 db 3e 00 00 31 ff 4c 89 f6 e8 91 3f 19 00 4d 85 f6 0f 85 76 01 00 00 93 42 19 00 48 b8 00 00 00 00 00 fc ff df 48 03 04 24 48 c7 00 RSP: 0018:ffff888008ecf630 EFLAGS: 00000202 RAX: 00000000000f0c1f RBX: 0000000000000000 RCX: ffffffff8128663f RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff888008ecf7d8 R08: 0000000000000001 R09: ffffffff86a5c7c7 R10: fffffbfff0d4b8f8 R11: 0000000000000001 R12: 0000000000000001 R13: ffffffff86da8ba0 R14: 0000000000000200 R15: ffffffff8549fcf8 console_unlock+0x36c/0x590 vprintk_emit+0x1b9/0x550 vprintk+0x80/0x90 _printk+0xba/0xed show_opcodes.cold+0x1c/0x21 show_iret_regs+0xd/0x33 __show_regs+0x1e/0x60 show_regs+0x2f/0x40 __warn+0xe2/0x190 report_bug+0x1bc/0x210 handle_bug+0x3c/0x60 exc_invalid_op+0x14/0x40 asm_exc_invalid_op+0x1b/0x20 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:ffff888008ecfbd8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff888008ec0000 RSI: ffffffff812b6848 RDI: ffffed10011d9f6d RBP: ffff888036492c00 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff888036492bc8 R13: ffff88802c2b9828 R14: 0000000000000000 R15: ffff8880180032f8 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: 986149 hardirqs last enabled at (986148): [] _raw_spin_unlock_irq+0x1f/0x40 hardirqs last disabled at (986149): [] _raw_spin_lock_irqsave+0x4e/0x50 softirqs last enabled at (986062): [] __irq_exit_rcu+0x113/0x170 softirqs last disabled at (986145): [] __irq_exit_rcu+0x113/0x170 ---[ end trace 0000000000000000 ]--- RSP: 0018:ffff888008ecfbd8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff888008ec0000 RSI: ffffffff812b6848 RDI: ffffed10011d9f6d RBP: ffff888036492c00 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff888036492bc8 R13: ffff88802c2b9828 R14: 0000000000000000 R15: ffff8880180032f8 FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7a88583368 CR3: 000000001d128000 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: 987401 hardirqs last enabled at (987411): [] __up_console_sem+0x78/0x80 hardirqs last disabled at (987422): [] __up_console_sem+0x5d/0x80 softirqs last enabled at (987082): [] __irq_exit_rcu+0x113/0x170 softirqs last disabled at (986995): [] __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 ffff888036492c48 by task kworker/1:1/32 CPU: 1 PID: 32 Comm: kworker/1:1 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 process_one_work+0xa0f/0x1690 worker_thread+0x637/0x1250 kthread+0x2ed/0x3a0 ret_from_fork+0x22/0x30 Allocated by task 837: 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 32: 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 ffff888036492bc8 which belongs to the cache kernfs_node_cache of size 168 The buggy address is located 128 bytes inside of 168-byte region [ffff888036492bc8, ffff888036492c70) The buggy address belongs to the physical page: page:0000000006ff080c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x36492 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: ffff888036492b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888036492b80: 00 fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb >ffff888036492c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ^ ffff888036492c80: fc fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00 ffff888036492d00: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc ================================================================== ------------[ cut here ]------------ WARNING: CPU: 1 PID: 7935 at fs/kernfs/dir.c:504 kernfs_get.part.0+0x69/0x80 Modules linked in: CPU: 1 PID: 7935 Comm: syz-executor.5 Tainted: G B 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 RIP: 0010:kernfs_get.part.0+0x69/0x80 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:ffff8880393f7a40 EFLAGS: 00010093 RAX: 0000000000000000 RBX: ffff888036492bc8 RCX: 0000000000000000 RDX: ffff888038f80000 RSI: ffffffff819d2579 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 1ffffffff0a01e40 R14: ffff888036492bc8 R15: ffff888037d13d30 FS: 0000555556a31400(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7a88583368 CR3: 00000000391d2000 CR4: 0000000000350ee0 Call Trace: kernfs_get+0x1b/0x30 kernfs_notify+0x180/0x350 cgroup_file_notify+0xf5/0x1a0 pids_can_fork+0x22f/0x370 cgroup_can_fork+0x332/0x11b0 copy_process+0x4023/0x6d60 kernel_clone+0xe7/0xa60 __do_sys_clone+0xba/0x100 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7fa575173f41 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 RSP: 002b:00007ffe32031268 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fa5726a6700 RCX: 00007fa575173f41 RDX: 00007fa5726a69d0 RSI: 00007fa5726a62f0 RDI: 00000000003d0f00 RBP: 00007ffe320314a0 R08: 00007fa5726a6700 R09: 00007fa5726a6700 R10: 00007fa5726a69d0 R11: 0000000000000206 R12: 00007ffe3203131e R13: 00007ffe3203131f R14: 00007fa5726a6300 R15: 0000555556a32e70 irq event stamp: 10302 hardirqs last enabled at (10301): [] _raw_spin_unlock_irqrestore+0x28/0x50 hardirqs last disabled at (10302): [] __schedule+0x11d9/0x24a0 softirqs last enabled at (10264): [] fpu_clone+0x3be/0xb00 softirqs last disabled at (10262): [] fpu_clone+0x331/0xb00 ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 83 e2 07 and $0x7,%edx 3: 38 d0 cmp %dl,%al 5: 7f 08 jg 0xf 7: 84 c0 test %al,%al 9: 0f 85 d5 02 00 00 jne 0x2e4 f: 88 5d 00 mov %bl,0x0(%rbp) 12: e8 db 3e 00 00 callq 0x3ef2 17: 31 ff xor %edi,%edi 19: 4c 89 f6 mov %r14,%rsi 1c: e8 91 3f 19 00 callq 0x193fb2 21: 4d 85 f6 test %r14,%r14 24: 0f 85 76 01 00 00 jne 0x1a0 * 2a: e8 93 42 19 00 callq 0x1942c2 <-- trapping instruction 2f: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 36: fc ff df 39: 48 03 04 24 add (%rsp),%rax 3d: 48 rex.W 3e: c7 .byte 0xc7