R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd8fd94880
R13: 00007fbd2da0471f R14: 0000000000030527 R15: 00007ffd8fd948c0
 </TASK>
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: use-after-free in d_inode include/linux/dcache.h:525 [inline]
BUG: KASAN: use-after-free in d_delete_notify include/linux/fsnotify.h:287 [inline]
BUG: KASAN: use-after-free in vfs_rmdir+0x253/0x500 fs/namei.c:4211
Read of size 8 at addr ffff8881179e9470 by task syz-executor/3989

CPU: 0 PID: 3989 Comm: syz-executor Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x71/0x200 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:420
 kasan_report+0x122/0x150 mm/kasan/report.c:524
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351
 d_inode include/linux/dcache.h:525 [inline]
 d_delete_notify include/linux/fsnotify.h:287 [inline]
 vfs_rmdir+0x253/0x500 fs/namei.c:4211
 incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1995
 deactivate_locked_super+0xb5/0x120 fs/super.c:334
 deactivate_super+0xaf/0xe0 fs/super.c:365
 cleanup_mnt+0x474/0x500 fs/namespace.c:1191
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1198
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbd2d99bf17
Code: a2 c7 05 7c 96 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd8fd93738 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fbd2d99bf17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd8fd937f0
RBP: 00007ffd8fd937f0 R08: 00007ffd8fd947f0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd8fd94880
R13: 00007fbd2da0471f R14: 0000000000030527 R15: 00007ffd8fd948c0
 </TASK>

Allocated by task 4366:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:333
 kasan_slab_alloc include/linux/kasan.h:202 [inline]
 slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3382 [inline]
 slab_alloc mm/slub.c:3392 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3399 [inline]
 kmem_cache_alloc_lru+0x104/0x280 mm/slub.c:3415
 __d_alloc+0x34/0x6c0 fs/dcache.c:1774
 d_alloc fs/dcache.c:1854 [inline]
 d_alloc_parallel+0xe2/0x12e0 fs/dcache.c:2647
 __lookup_slow+0x14f/0x410 fs/namei.c:1682
 lookup_one_len+0x19d/0x2e0 fs/namei.c:2747
 incfs_lookup_dentry+0x60/0xb0 fs/incfs/data_mgmt.c:210
 open_or_create_special_dir+0x4f/0x1d0 fs/incfs/vfs.c:475
 incfs_mount_fs+0x42f/0x890 fs/incfs/vfs.c:1890
 legacy_get_tree+0xfe/0x1a0 fs/fs_context.c:632
 vfs_get_tree+0x9a/0x270 fs/super.c:1575
 do_new_mount+0x25a/0xa20 fs/namespace.c:3078
 path_mount+0x659/0xfc0 fs/namespace.c:3408
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x320/0x390 fs/namespace.c:3606
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3606
 x64_sys_call+0x65d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 4371:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:241
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1750 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776
 slab_free mm/slub.c:3712 [inline]
 kmem_cache_free+0x12d/0x300 mm/slub.c:3737
 __d_free+0x23/0x30 fs/dcache.c:298
 rcu_do_batch+0x52a/0xbc0 kernel/rcu/tree.c:2297
 rcu_core+0x5c3/0xe80 kernel/rcu/tree.c:2557
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2574
 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642
 __do_softirq kernel/softirq.c:680 [inline]
 invoke_softirq kernel/softirq.c:497 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:729
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:741
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1118
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 __call_rcu_common kernel/rcu/tree.c:2807 [inline]
 call_rcu+0xcf/0xf90 kernel/rcu/tree.c:2926
 dentry_free+0xbd/0x150 fs/dcache.c:-1
 __dentry_kill+0x529/0x670 fs/dcache.c:625
 dentry_kill+0xc0/0x2a0 fs/dcache.c:-1
 dput+0x42/0x80 fs/dcache.c:918
 vfs_rmdir+0x21d/0x500 fs/namei.c:4209
 incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1995
 deactivate_locked_super+0xb5/0x120 fs/super.c:334
 deactivate_super+0xaf/0xe0 fs/super.c:365
 cleanup_mnt+0x474/0x500 fs/namespace.c:1191
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1198
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Second to last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 __call_rcu_common kernel/rcu/tree.c:2807 [inline]
 call_rcu+0xcf/0xf90 kernel/rcu/tree.c:2926
 dentry_free+0xbd/0x150 fs/dcache.c:-1
 __dentry_kill+0x529/0x670 fs/dcache.c:625
 dentry_kill+0xc0/0x2a0 fs/dcache.c:-1
 dput+0x42/0x80 fs/dcache.c:918
 proc_invalidate_siblings_dcache+0x2bf/0x3c0 fs/proc/inode.c:155
 proc_sys_invalidate_dcache fs/proc/proc_sysctl.c:287 [inline]
 start_unregistering fs/proc/proc_sysctl.c:312 [inline]
 drop_sysctl_table+0x16a/0x430 fs/proc/proc_sysctl.c:1727
 unregister_sysctl_table+0x75/0x120 fs/proc/proc_sysctl.c:1769
 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:175
 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7219 [inline]
 addrconf_sysctl_unregister net/ipv6/addrconf.c:7247 [inline]
 addrconf_ifdown+0x1604/0x1950 net/ipv6/addrconf.c:3977
 addrconf_notify+0x39f/0xe40 net/ipv6/addrconf.c:-1
 notifier_call_chain kernel/notifier.c:87 [inline]
 raw_notifier_call_chain+0xa1/0x110 kernel/notifier.c:455
 call_netdevice_notifiers_info net/core/dev.c:2009 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2047 [inline]
 call_netdevice_notifiers net/core/dev.c:2061 [inline]
 unregister_netdevice_many+0x102c/0x18e0 net/core/dev.c:10967
 unregister_netdevice_queue net/core/dev.c:10898 [inline]
 unregister_netdevice include/linux/netdevice.h:3109 [inline]
 unregister_netdev+0x148/0x1c0 net/core/dev.c:11026
 ipheth_disconnect+0x8d/0x2e0 drivers/net/usb/ipheth.c:527
 usb_unbind_interface+0x223/0x8d0 drivers/usb/core/driver.c:459
 device_remove drivers/base/dd.c:550 [inline]
 __device_release_driver drivers/base/dd.c:1283 [inline]
 device_release_driver_internal+0x508/0x820 drivers/base/dd.c:1309
 device_release_driver+0x19/0x20 drivers/base/dd.c:1332
 bus_remove_device+0x2ee/0x350 drivers/base/bus.c:531
 device_del+0x6bc/0xec0 drivers/base/core.c:3886
 usb_disable_device+0x3a8/0x750 drivers/usb/core/message.c:1414
 usb_disconnect+0x31e/0x860 drivers/usb/core/hub.c:2339
 hub_port_connect drivers/usb/core/hub.c:5433 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5734 [inline]
 port_event drivers/usb/core/hub.c:5898 [inline]
 hub_event+0x1c1b/0x46b0 drivers/usb/core/hub.c:5980
 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302
 worker_thread+0xa29/0x11e0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff8881179e9440
 which belongs to the cache dentry of size 208
The buggy address is located 48 bytes inside of
 208-byte region [ffff8881179e9440, ffff8881179e9510)

The buggy address belongs to the physical page:
page:ffffea00045e7a40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1179e9
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 ffffea0004ccc880 dead000000000002 ffff8881001ec900
raw: 0000000000000000 00000000000f000f 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Reclaimable, gfp_mask 0x12cd0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_RECLAIMABLE), pid 286, tgid 286 (syz-executor), ts 23056699091, free_ts 0
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2643
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2650
 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4554
 __alloc_pages+0x1d9/0x480 mm/page_alloc.c:5868
 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
 allocate_slab mm/slub.c:1967 [inline]
 new_slab+0x98/0x3d0 mm/slub.c:2020
 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177
 __slab_alloc+0x5e/0xa0 mm/slub.c:3263
 slab_alloc_node mm/slub.c:3348 [inline]
 slab_alloc mm/slub.c:3392 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3399 [inline]
 kmem_cache_alloc_lru+0x144/0x280 mm/slub.c:3415
 __d_alloc+0x34/0x6c0 fs/dcache.c:1774
 d_alloc_pseudo+0x1d/0x70 fs/dcache.c:1906
 alloc_file_pseudo+0xe0/0x200 fs/file_table.c:265
 sock_alloc_file+0xba/0x270 net/socket.c:465
 sock_map_fd net/socket.c:489 [inline]
 __sys_socket+0x135/0x1a0 net/socket.c:1669
 __do_sys_socket net/socket.c:1674 [inline]
 __se_sys_socket net/socket.c:1672 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1672
 x64_sys_call+0x449/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:42
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8881179e9300: fc fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00
 ffff8881179e9380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881179e9400: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
                                                             ^
 ffff8881179e9480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881179e9500: fb fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000170
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 1091a1067 P4D 1091a1067 PUD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3989 Comm: syz-executor Tainted: G    B   W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline]
RIP: 0010:arch_atomic_inc_return include/linux/atomic/atomic-arch-fallback.h:440 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:199 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:455
Code: 33 36 7c df 55 48 89 e5 41 56 53 48 89 fb e8 61 7d ab ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 b0 ac f0 ff 41 be 01 00 00 00 <f0> 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 51
RSP: 0018:ffffc90000e17c78 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81c5cc70
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000170
RBP: ffffc90000e17c88 R08: 0000000000000000 R09: 1ffffffff0f2defc
R10: dffffc0000000000 R11: fffffbfff0f2defd R12: ffff88811a75edec
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
FS:  0000555559761500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 000000012d0f1000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 d_delete_notify include/linux/fsnotify.h:289 [inline]
 vfs_rmdir+0x25f/0x500 fs/namei.c:4211
 incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1995
 deactivate_locked_super+0xb5/0x120 fs/super.c:334
 deactivate_super+0xaf/0xe0 fs/super.c:365
 cleanup_mnt+0x474/0x500 fs/namespace.c:1191
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1198
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbd2d99bf17
Code: a2 c7 05 7c 96 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd8fd93738 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fbd2d99bf17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd8fd937f0
RBP: 00007ffd8fd937f0 R08: 00007ffd8fd947f0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd8fd94880
R13: 00007fbd2da0471f R14: 0000000000030527 R15: 00007ffd8fd948c0
 </TASK>
Modules linked in:
CR2: 0000000000000170
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline]
RIP: 0010:arch_atomic_inc_return include/linux/atomic/atomic-arch-fallback.h:440 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:199 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:455
Code: 33 36 7c df 55 48 89 e5 41 56 53 48 89 fb e8 61 7d ab ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 b0 ac f0 ff 41 be 01 00 00 00 <f0> 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 51
RSP: 0018:ffffc90000e17c78 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81c5cc70
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000170
RBP: ffffc90000e17c88 R08: 0000000000000000 R09: 1ffffffff0f2defc
R10: dffffc0000000000 R11: fffffbfff0f2defd R12: ffff88811a75edec
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
FS:  0000555559761500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 000000012d0f1000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	33 36                	xor    (%rsi),%esi
   2:	7c df                	jl     0xffffffe3
   4:	55                   	push   %rbp
   5:	48 89 e5             	mov    %rsp,%rbp
   8:	41 56                	push   %r14
   a:	53                   	push   %rbx
   b:	48 89 fb             	mov    %rdi,%rbx
   e:	e8 61 7d ab ff       	call   0xffab7d74
  13:	48 8d bb 70 01 00 00 	lea    0x170(%rbx),%rdi
  1a:	be 04 00 00 00       	mov    $0x4,%esi
  1f:	e8 b0 ac f0 ff       	call   0xfff0acd4
  24:	41 be 01 00 00 00    	mov    $0x1,%r14d
* 2a:	f0 44 0f c1 b3 70 01 	lock xadd %r14d,0x170(%rbx) <-- trapping instruction
  31:	00 00
  33:	41 ff c6             	inc    %r14d
  36:	bf 02 00 00 00       	mov    $0x2,%edi
  3b:	44 89 f6             	mov    %r14d,%esi
  3e:	e8                   	.byte 0xe8
  3f:	51                   	push   %rcx