================================================================== BUG: KASAN: slab-use-after-free in __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline] BUG: KASAN: slab-use-after-free in _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158 Read of size 1 at addr ffff88805669e0d0 by task syz.3.1207/9910 CPU: 0 UID: 0 PID: 9910 Comm: syz.3.1207 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 __kasan_check_byte+0x36/0x50 mm/kasan/common.c:574 kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire kernel/locking/lockdep.c:5842 [inline] lock_acquire+0x132/0x370 kernel/locking/lockdep.c:5825 __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158 spin_lock include/linux/spinlock.h:342 [inline] lockref_get+0x15/0x50 lib/lockref.c:50 dget include/linux/dcache.h:364 [inline] __simple_recursive_removal+0x3d/0x5c0 fs/libfs.c:601 debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:781 i2c_device_probe+0x6e2/0xd10 drivers/i2c/i2c-core-base.c:610 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:620 device_add+0x121d/0x1970 drivers/base/core.c:3772 i2c_new_client_device+0x660/0xd30 drivers/i2c/i2c-core-base.c:1019 new_device_store+0x20f/0x420 drivers/i2c/i2c-core-base.c:1307 dev_attr_store+0x58/0x80 drivers/base/core.c:2505 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe56e79e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe56f624028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe56ea26090 RCX: 00007fe56e79e0d9 RDX: 0000000000000012 RSI: 0000200000000800 RDI: 0000000000000005 RBP: 00007fe56e835024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe56ea26128 R14: 00007fe56ea26090 R15: 00007ffdddd6f828 Allocated by task 9910: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_lru_noprof+0x267/0x6a0 mm/slub.c:4950 __d_alloc+0x35/0xa50 fs/dcache.c:1902 d_alloc+0x4a/0x1e0 fs/dcache.c:1981 lookup_one_qstr_excl+0x171/0x250 fs/namei.c:1806 __start_dirop fs/namei.c:2920 [inline] start_dirop+0x59/0xb0 fs/namei.c:2942 simple_start_creating+0xf9/0x110 fs/libfs.c:2305 debugfs_start_creating.part.0+0x82/0x170 fs/debugfs/inode.c:394 debugfs_start_creating fs/debugfs/inode.c:371 [inline] debugfs_create_dir+0x72/0x440 fs/debugfs/inode.c:572 i2c_device_probe+0x5f5/0xd10 drivers/i2c/i2c-core-base.c:588 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:620 device_add+0x121d/0x1970 drivers/base/core.c:3772 i2c_new_client_device+0x660/0xd30 drivers/i2c/i2c-core-base.c:1019 new_device_store+0x20f/0x420 drivers/i2c/i2c-core-base.c:1307 dev_attr_store+0x58/0x80 drivers/base/core.c:2505 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 9897: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kmem_cache_free+0x127/0x6b0 mm/slub.c:6504 rcu_do_batch kernel/rcu/tree.c:2645 [inline] rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2897 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xac/0xe0 kernel/softirq.c:510 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline] copy_fpstate_to_sigframe+0x2bd/0xae0 arch/x86/kernel/fpu/signal.c:225 get_sigframe+0x3fb/0x940 arch/x86/kernel/signal.c:163 x64_setup_rt_frame+0x12f/0xce0 arch/x86/kernel/signal_64.c:175 setup_rt_frame arch/x86/kernel/signal.c:250 [inline] handle_signal arch/x86/kernel/signal.c:294 [inline] arch_do_signal_or_restart+0x5ee/0x7e0 arch/x86/kernel/signal.c:339 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Last potentially related work creation: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556 __call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3159 dentry_free+0x145/0x2b0 fs/dcache.c:450 dentry_kill+0x5e8/0xc20 fs/dcache.c:845 finish_dput fs/dcache.c:1001 [inline] dput.part.0+0xd7/0x240 fs/dcache.c:1042 dput+0x1f/0x30 fs/dcache.c:1037 find_next_child+0x18f/0x280 fs/libfs.c:592 __simple_recursive_removal+0x2ab/0x5c0 fs/libfs.c:609 debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:781 i2c_del_adapter+0x17f/0x2d0 drivers/i2c/i2c-core-base.c:1829 release_nodes+0xa5/0x120 drivers/base/devres.c:546 devres_release_group+0x1c2/0x2d0 drivers/base/devres.c:739 hid_device_remove+0x107/0x270 drivers/hid/hid-core.c:2890 device_remove+0xcb/0x180 drivers/base/dd.c:616 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664 device_del+0x376/0x9b0 drivers/base/core.c:3961 hid_remove_device drivers/hid/hid-core.c:3071 [inline] hid_destroy_device+0x19c/0x240 drivers/hid/hid-core.c:3093 usbhid_disconnect+0xa0/0xe0 drivers/hid/usbhid/hid-core.c:1479 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:618 [inline] device_remove+0x12a/0x180 drivers/base/dd.c:610 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664 device_del+0x376/0x9b0 drivers/base/core.c:3961 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345 hub_port_connect drivers/usb/core/hub.c:5407 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x1c4f/0x4a60 drivers/usb/core/hub.c:5953 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88805669e000 which belongs to the cache dentry of size 312 The buggy address is located 208 bytes inside of freed 312-byte region [ffff88805669e000, ffff88805669e138) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805669f318 pfn:0x5669e head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88805669fed9 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801d2e0140 ffffea0001d41910 ffffea0001ed5b90 raw: ffff88805669f318 0000000800150010 00000000f5000000 ffff88805669fed9 head: 00fff00000000240 ffff88801d2e0140 ffffea0001d41910 ffffea0001ed5b90 head: ffff88805669f318 0000000800150010 00000000f5000000 ffff88805669fed9 head: 00fff00000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_RECLAIMABLE|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9202, tgid 9201 (syz.1.989), ts 294710791653, free_ts 240195795958 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab mm/slub.c:3380 [inline] new_slab+0xa2/0x640 mm/slub.c:3426 refill_objects+0xe3/0x410 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] kmem_cache_alloc_lru_noprof+0x46a/0x6a0 mm/slub.c:4950 __d_alloc+0x35/0xa50 fs/dcache.c:1902 d_alloc+0x4a/0x1e0 fs/dcache.c:1981 lookup_one_qstr_excl+0x171/0x250 fs/namei.c:1806 __start_dirop fs/namei.c:2920 [inline] start_dirop+0x59/0xb0 fs/namei.c:2942 simple_start_creating+0xf9/0x110 fs/libfs.c:2305 debugfs_start_creating.part.0+0x82/0x170 fs/debugfs/inode.c:394 debugfs_start_creating fs/debugfs/inode.c:371 [inline] __debugfs_create_file+0xb3/0x4f0 fs/debugfs/inode.c:428 debugfs_create_file_full+0x41/0x60 fs/debugfs/inode.c:460 kvm_create_vm_debugfs virt/kvm/kvm_main.c:1057 [inline] kvm_create_vm virt/kvm/kvm_main.c:1196 [inline] kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:5493 [inline] kvm_dev_ioctl+0x1797/0x1b50 virt/kvm/kvm_main.c:5535 page last free pid 8397 tgid 8397 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_noprof+0x26b/0x6a0 mm/slub.c:4931 new_handle fs/jbd2/transaction.c:457 [inline] jbd2__journal_start+0x194/0x6a0 fs/jbd2/transaction.c:485 __ext4_journal_start_sb+0x367/0x670 fs/ext4/ext4_jbd2.c:114 __ext4_journal_start fs/ext4/ext4_jbd2.h:242 [inline] ext4_dirty_inode+0xa1/0x130 fs/ext4/inode.c:6636 __mark_inode_dirty+0x1f3/0x16e0 fs/fs-writeback.c:2709 generic_update_time fs/inode.c:2257 [inline] file_update_time_flags+0x46b/0x500 fs/inode.c:2487 ext4_page_mkwrite+0x324/0x1850 fs/ext4/inode.c:6805 do_page_mkwrite+0x17a/0x440 mm/memory.c:3684 do_shared_fault mm/memory.c:5936 [inline] do_fault+0x3b5/0x1750 mm/memory.c:5998 do_pte_missing mm/memory.c:4566 [inline] handle_pte_fault mm/memory.c:6379 [inline] __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6517 handle_mm_fault+0x37b/0xa30 mm/memory.c:6686 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1343 Memory state around the buggy address: ffff88805669df80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805669e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805669e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805669e100: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa ffff88805669e180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================