R13: 00007f12180f5c05 R14: 00005555585974a8 R15: 00007ffefbeb4dd0 ---[ end trace d18da3de89883ee9 ]--- ================================================================== BUG: KASAN: use-after-free in d_inode include/linux/dcache.h:531 [inline] BUG: KASAN: use-after-free in d_delete_notify include/linux/fsnotify.h:262 [inline] BUG: KASAN: use-after-free in vfs_rmdir+0x23b/0x3e0 fs/namei.c:3865 Read of size 8 at addr ffff888166717cf0 by task syz-executor/20019 CPU: 0 PID: 20019 Comm: syz-executor Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0xe2/0x130 mm/kasan/report.c:452 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 d_inode include/linux/dcache.h:531 [inline] d_delete_notify include/linux/fsnotify.h:262 [inline] vfs_rmdir+0x23b/0x3e0 fs/namei.c:3865 incfs_kill_sb+0xfe/0x210 fs/incfs/vfs.c:1973 deactivate_locked_super+0xa0/0x100 fs/super.c:335 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x446/0x500 fs/namespace.c:1114 __cleanup_mnt+0x19/0x20 fs/namespace.c:1121 task_work_run+0x127/0x190 kernel/task_work.c:189 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa4f/0x2480 kernel/exit.c:872 do_group_exit+0x141/0x310 kernel/exit.c:986 __do_sys_exit_group kernel/exit.c:997 [inline] __se_sys_exit_group kernel/exit.c:995 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:995 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f1218072ba9 Code: Unable to access opcode bytes at RIP 0x7f1218072b7f. RSP: 002b:00007ffefbeb1958 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f12180f5c77 RCX: 00007f1218072ba9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000016 R08: 00007ffefbeaf6f6 R09: 00007ffefbeb2c10 R10: 000000000000000a R11: 0000000000000246 R12: 00007ffefbeb2c10 R13: 00007f12180f5c05 R14: 00005555585974a8 R15: 00007ffefbeb4dd0 Allocated by task 26739: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] __kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:463 kasan_slab_alloc include/linux/kasan.h:244 [inline] slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:580 slab_alloc_node mm/slub.c:2952 [inline] slab_alloc mm/slub.c:2960 [inline] kmem_cache_alloc+0x165/0x2e0 mm/slub.c:2965 __d_alloc+0x2d/0x6a0 fs/dcache.c:1714 d_alloc fs/dcache.c:1793 [inline] d_alloc_parallel+0xd6/0x1320 fs/dcache.c:2547 __lookup_slow+0x13e/0x3e0 fs/namei.c:1625 lookup_one_len+0x18e/0x2c0 fs/namei.c:2656 incfs_lookup_dentry+0x60/0xb0 fs/incfs/data_mgmt.c:210 open_or_create_special_dir+0x4f/0x1d0 fs/incfs/vfs.c:469 incfs_mount_fs+0x434/0x8c0 fs/incfs/vfs.c:1867 legacy_get_tree+0xed/0x190 fs/fs_context.c:593 vfs_get_tree+0x89/0x260 fs/super.c:1572 do_new_mount+0x25a/0xa20 fs/namespace.c:2997 path_mount+0x572/0xc80 fs/namespace.c:3327 do_mount fs/namespace.c:3340 [inline] __do_sys_mount fs/namespace.c:3548 [inline] __se_sys_mount+0x318/0x380 fs/namespace.c:3525 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3525 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Freed by task 26758: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370 kasan_slab_free include/linux/kasan.h:220 [inline] slab_free_hook mm/slub.c:1600 [inline] slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1626 slab_free mm/slub.c:3208 [inline] kmem_cache_free+0x100/0x2d0 mm/slub.c:3224 __d_free+0x23/0x30 fs/dcache.c:271 rcu_do_batch+0x4df/0xa80 kernel/rcu/tree.c:2494 rcu_core+0x55f/0xd60 kernel/rcu/tree.c:2735 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2748 __do_softirq+0x255/0x563 kernel/softirq.c:309 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu kernel/rcu/tree.c:2980 [inline] call_rcu+0x10e/0x1050 kernel/rcu/tree.c:3054 dentry_free+0xbd/0x150 fs/dcache.c:-1 __dentry_kill+0x50a/0x650 fs/dcache.c:597 dentry_kill+0xc0/0x2a0 fs/dcache.c:-1 dput+0x42/0x80 fs/dcache.c:883 vfs_rmdir+0x204/0x3e0 fs/namei.c:3863 incfs_kill_sb+0xfe/0x210 fs/incfs/vfs.c:1973 deactivate_locked_super+0xa0/0x100 fs/super.c:335 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x446/0x500 fs/namespace.c:1114 __cleanup_mnt+0x19/0x20 fs/namespace.c:1121 task_work_run+0x127/0x190 kernel/task_work.c:189 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa4f/0x2480 kernel/exit.c:872 do_group_exit+0x141/0x310 kernel/exit.c:986 __do_sys_exit_group kernel/exit.c:997 [inline] __se_sys_exit_group kernel/exit.c:995 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:995 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb The buggy address belongs to the object at ffff888166717cc0 which belongs to the cache dentry of size 208 The buggy address is located 48 bytes inside of 208-byte region [ffff888166717cc0, ffff888166717d90) The buggy address belongs to the page: page:ffffea000599c5c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x166717 flags: 0x4000000000000200(slab) raw: 4000000000000200 ffffea000440bfc0 0000000d0000000d ffff88810018b080 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 0x112cd0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__GFP_RECLAIMABLE), pid 22169, ts 1181762437248, free_ts 1116545396078 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x179/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5370 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1813 [inline] new_slab+0x84/0x3f0 mm/slub.c:1874 new_slab_objects mm/slub.c:2632 [inline] ___slab_alloc+0x2a6/0x450 mm/slub.c:2796 __slab_alloc+0x63/0xa0 mm/slub.c:2836 slab_alloc_node mm/slub.c:2918 [inline] slab_alloc mm/slub.c:2960 [inline] kmem_cache_alloc+0x1af/0x2e0 mm/slub.c:2965 __d_alloc+0x2d/0x6a0 fs/dcache.c:1714 d_alloc+0x4b/0x1d0 fs/dcache.c:1793 __lookup_hash+0xcb/0x250 fs/namei.c:1537 filename_create+0x1d4/0x680 fs/namei.c:3608 user_path_create fs/namei.c:3665 [inline] do_mkdirat+0x5e/0x340 fs/namei.c:3805 __do_sys_mkdirat fs/namei.c:3823 [inline] __se_sys_mkdirat fs/namei.c:3821 [inline] __x64_sys_mkdirat+0x7b/0x90 fs/namei.c:3821 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1349 [inline] __free_pages_ok+0x7fc/0x820 mm/page_alloc.c:1629 free_the_page mm/page_alloc.c:5431 [inline] __free_pages+0xdd/0x380 mm/page_alloc.c:5440 free_pages+0x82/0x90 mm/page_alloc.c:5451 free_pg_vec net/packet/af_packet.c:4347 [inline] packet_set_ring+0x18db/0x23a0 net/packet/af_packet.c:4566 packet_release+0x728/0xc60 net/packet/af_packet.c:3163 __sock_release net/socket.c:597 [inline] sock_close+0xe0/0x270 net/socket.c:1286 __fput+0x2fb/0x770 fs/file_table.c:281 ____fput+0x15/0x20 fs/file_table.c:314 task_work_run+0x127/0x190 kernel/task_work.c:189 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop+0xcb/0xe0 kernel/entry/common.c:172 exit_to_user_mode_prepare+0x76/0xa0 kernel/entry/common.c:199 syscall_exit_to_user_mode+0x1d/0x40 kernel/entry/common.c:274 do_syscall_64+0x3d/0x40 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x61/0xcb Memory state around the buggy address: ffff888166717b80: fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb ffff888166717c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888166717c80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff888166717d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888166717d80: fb fb fc fc fc fc fc fc fc fc 00 00 00 00 00 00 ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000170 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] PREEMPT SMP KASAN CPU: 1 PID: 20019 Comm: syz-executor Tainted: G B W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025 RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline] RIP: 0010:arch_atomic_inc_return include/linux/atomic-arch-fallback.h:286 [inline] RIP: 0010:atomic_inc_return include/asm-generic/atomic-instrumented.h:251 [inline] RIP: 0010:ihold+0x26/0x60 fs/inode.c:423 Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 41 2b b8 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 80 1a f2 ff 41 be 01 00 00 00 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 c1 RSP: 0018:ffffc9000113fba8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000282 RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000170 RBP: ffffc9000113fbb8 R08: 0000000000000000 R09: 0000000000000003 R10: fffffbfff0d8ee48 R11: 1ffffffff0d8ee48 R12: 1ffff1102cce2f9e R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000170 CR3: 000000000620f000 CR4: 00000000003526a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: d_delete_notify include/linux/fsnotify.h:264 [inline] vfs_rmdir+0x247/0x3e0 fs/namei.c:3865 incfs_kill_sb+0xfe/0x210 fs/incfs/vfs.c:1973 deactivate_locked_super+0xa0/0x100 fs/super.c:335 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x446/0x500 fs/namespace.c:1114 __cleanup_mnt+0x19/0x20 fs/namespace.c:1121 task_work_run+0x127/0x190 kernel/task_work.c:189 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa4f/0x2480 kernel/exit.c:872 do_group_exit+0x141/0x310 kernel/exit.c:986 __do_sys_exit_group kernel/exit.c:997 [inline] __se_sys_exit_group kernel/exit.c:995 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:995 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f1218072ba9 Code: Unable to access opcode bytes at RIP 0x7f1218072b7f. RSP: 002b:00007ffefbeb1958 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f12180f5c77 RCX: 00007f1218072ba9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000016 R08: 00007ffefbeaf6f6 R09: 00007ffefbeb2c10 R10: 000000000000000a R11: 0000000000000246 R12: 00007ffefbeb2c10 R13: 00007f12180f5c05 R14: 00005555585974a8 R15: 00007ffefbeb4dd0 Modules linked in: CR2: 0000000000000170 ---[ end trace d18da3de89883eea ]--- RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline] RIP: 0010:arch_atomic_inc_return include/linux/atomic-arch-fallback.h:286 [inline] RIP: 0010:atomic_inc_return include/asm-generic/atomic-instrumented.h:251 [inline] RIP: 0010:ihold+0x26/0x60 fs/inode.c:423 Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 41 2b b8 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 80 1a f2 ff 41 be 01 00 00 00 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 c1 RSP: 0018:ffffc9000113fba8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000282 RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000170 RBP: ffffc9000113fbb8 R08: 0000000000000000 R09: 0000000000000003 R10: fffffbfff0d8ee48 R11: 1ffffffff0d8ee48 R12: 1ffff1102cce2f9e R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000170 CR3: 000000000620f000 CR4: 00000000003526a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 00 add %al,(%rax) 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 41 2b b8 ff call 0xffb82b54 13: 48 8d bb 70 01 00 00 lea 0x170(%rbx),%rdi 1a: be 04 00 00 00 mov $0x4,%esi 1f: e8 80 1a f2 ff call 0xfff21aa4 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: c1 .byte 0xc1