------------[ cut here ]------------ kernfs_put: syz3/pids.events: released with incorrect active_ref 0 WARNING: CPU: 1 PID: 18907 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540 Modules linked in: CPU: 1 PID: 18907 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:ffff88804e34fbd8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff88800972b580 RSI: ffffffff812b6848 RDI: ffffed1009c69f6d RBP: ffff8880191aea30 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880191ae9f8 R13: ffff88801a6d10e8 R14: 0000000000000000 R15: ffff88800f2305a0 FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2cec800004 CR3: 000000004bd04000 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: 3772705 hardirqs last enabled at (3772717): [] __up_console_sem+0x78/0x80 hardirqs last disabled at (3772726): [] __up_console_sem+0x5d/0x80 softirqs last enabled at (3772296): [] __irq_exit_rcu+0x113/0x170 softirqs last disabled at (3772255): [] __irq_exit_rcu+0x113/0x170 ---[ end trace 0000000000000000 ]--- ================================================================== ------------[ cut here ]------------ BUG: KASAN: use-after-free in llist_del_first+0x89/0xa0 Read of size 8 at addr ffff8880191aea78 by task kworker/1:0/18907 CPU: 1 PID: 18907 Comm: kworker/1:0 Tainted: G W 5.19.0-rc4-next-20220701 #1 WARNING: CPU: 0 PID: 80754 at fs/kernfs/dir.c:504 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 Modules linked in: Workqueue: events kernfs_notify_workfn Call Trace: CPU: 0 PID: 80754 Comm: syz-executor.3 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 dump_stack_lvl+0x8b/0xb3 RIP: 0010:kernfs_get.part.0+0x69/0x80 print_report.cold+0x5e/0x5e1 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:ffff88804acdfa40 EFLAGS: 00010093 kasan_report+0xb1/0x1b0 RAX: 0000000000000000 RBX: ffff8880191ae9f8 RCX: 0000000000000000 llist_del_first+0x89/0xa0 RDX: ffff88804f8c9ac0 RSI: ffffffff819d2579 RDI: 0000000000000005 kernfs_notify_workfn+0x78/0x560 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 1ffffffff0a01e40 R14: ffff8880191ae9f8 R15: ffff88800e200d30 FS: 0000555557133400(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 process_one_work+0xa0f/0x1690 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc7456bafe0 CR3: 00000000508a0000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400 worker_thread+0x637/0x1250 Call Trace: kernfs_get+0x1b/0x30 kthread+0x2ed/0x3a0 kernfs_notify+0x180/0x350 cgroup_file_notify+0xf5/0x1a0 ret_from_fork+0x22/0x30 pids_can_fork+0x22f/0x370 Allocated by task 301: cgroup_can_fork+0x332/0x11b0 kasan_save_stack+0x1e/0x40 copy_process+0x4023/0x6d60 __kasan_slab_alloc+0x66/0x80 kmem_cache_alloc+0x1b1/0x490 kernel_clone+0xe7/0xa60 __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 __do_sys_clone+0xba/0x100 cgroup_apply_control_enable+0x3ae/0xa40 cgroup_mkdir+0x824/0x11f0 kernfs_iop_mkdir+0x149/0x1d0 do_syscall_64+0x3b/0x90 vfs_mkdir+0x417/0x6a0 entry_SYSCALL_64_after_hwframe+0x46/0xb0 do_mkdirat+0x17b/0x2e0 RIP: 0033:0x7fc7455a8f41 __x64_sys_mkdir+0xf2/0x140 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 do_syscall_64+0x3b/0x90 RSP: 002b:00007fff4343f468 EFLAGS: 00000206 entry_SYSCALL_64_after_hwframe+0x46/0xb0 ORIG_RAX: 0000000000000038 Freed by task 18907: RAX: ffffffffffffffda RBX: 00007fc742afc700 RCX: 00007fc7455a8f41 kasan_save_stack+0x1e/0x40 RDX: 00007fc742afc9d0 RSI: 00007fc742afc2f0 RDI: 00000000003d0f00 kasan_set_track+0x21/0x30 RBP: 00007fff4343f6a0 R08: 00007fc742afc700 R09: 00007fc742afc700 kasan_set_free_info+0x20/0x30 R10: 00007fc742afc9d0 R11: 0000000000000206 R12: 00007fff4343f51e __kasan_slab_free+0x108/0x190 R13: 00007fff4343f51f R14: 00007fc742afc300 R15: 0000555557134d50 kmem_cache_free+0xfb/0x600 kernfs_put.part.0+0x2c7/0x540 irq event stamp: 10802 kernfs_put+0x42/0x50 hardirqs last enabled at (10801): [] _raw_spin_unlock_irq+0x1f/0x40 kernfs_notify_workfn+0x417/0x560 hardirqs last disabled at (10802): [] _raw_spin_lock_irqsave+0x4e/0x50 process_one_work+0xa0f/0x1690 softirqs last enabled at (10786): [] fpu_clone+0x3be/0xb00 worker_thread+0x637/0x1250 softirqs last disabled at (10784): [] fpu_clone+0x331/0xb00 kthread+0x2ed/0x3a0 ---[ end trace 0000000000000000 ]--- ret_from_fork+0x22/0x30 The buggy address belongs to the object at ffff8880191ae9f8 which belongs to the cache kernfs_node_cache of size 168 The buggy address is located 128 bytes inside of 168-byte region [ffff8880191ae9f8, ffff8880191aeaa0) The buggy address belongs to the physical page: page:000000009600a451 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x191ae 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: ffff8880191ae900: fc fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880191ae980: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fa >ffff8880191aea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880191aea80: fb fb fb fb fc fc fc fc fc fc fc fc 00 00 00 00 ffff8880191aeb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== program syz-executor.1 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.1 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.1 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.1 is using a deprecated SCSI ioctl, please convert it to SG_IO ata2: lost interrupt (Status 0x58) ata2: found unknown device (class 0) ---------------- 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