================================================================== BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:681 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x6cb/0xcc0 kernel/locking/mutex.c:747 Read of size 8 at addr ffff888026028060 by task khidpd_15c25886/23244 CPU: 1 PID: 23244 Comm: khidpd_15c25886 Not tainted 6.6.96-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x230 mm/kasan/report.c:475 kasan_report+0x117/0x150 mm/kasan/report.c:588 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] __mutex_lock_common kernel/locking/mutex.c:681 [inline] __mutex_lock+0x6cb/0xcc0 kernel/locking/mutex.c:747 l2cap_unregister_user+0x6a/0x1a0 net/bluetooth/l2cap_core.c:1728 hidp_session_thread+0x3c8/0x410 net/bluetooth/hidp/core.c:1304 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 23131: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc+0xb4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] hci_alloc_dev_priv+0x27/0x2000 net/bluetooth/hci_core.c:2423 hci_alloc_dev include/net/bluetooth/hci_core.h:1627 [inline] __vhci_create_device drivers/bluetooth/hci_vhci.c:399 [inline] vhci_create_device+0x11b/0x6e0 drivers/bluetooth/hci_vhci.c:472 vhci_get_user drivers/bluetooth/hci_vhci.c:529 [inline] vhci_write+0x3b5/0x470 drivers/bluetooth/hci_vhci.c:609 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 fs/read_write.c:584 ksys_write+0x147/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 23131: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 bt_host_release+0x82/0x90 net/bluetooth/hci_sysfs.c:87 device_release+0x96/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x221/0x470 lib/kobject.c:737 vhci_release+0x8b/0xd0 drivers/bluetooth/hci_vhci.c:667 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x90b/0x23c0 kernel/exit.c:883 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xd2c/0x1020 kernel/workqueue.c:1804 queue_work_on+0x121/0x1e0 kernel/workqueue.c:1835 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1746 [inline] __run_timers+0x558/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 The buggy address belongs to the object at ffff888026028000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 96 bytes inside of freed 8192-byte region [ffff888026028000, ffff88802602a000) The buggy address belongs to the physical page: page:ffffea0000980a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26028 head:ffffea0000980a00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017842280 ffffea0001a1f400 dead000000000002 raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 11954, tgid 11953 (syz.4.1092), ts 792284607700, free_ts 792277886997 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] audit_log_d_path+0xb5/0x190 kernel/audit.c:2150 audit_log_d_path_exe+0x45/0x70 kernel/audit.c:2221 audit_log_task+0x210/0x2e0 kernel/auditsc.c:2963 audit_seccomp+0x85/0x180 kernel/auditsc.c:3010 seccomp_log kernel/seccomp.c:1003 [inline] __seccomp_filter+0x18e2/0x1ba0 kernel/seccomp.c:1324 syscall_trace_enter+0xa7/0x150 kernel/entry/common.c:72 do_syscall_64+0x28/0xb0 arch/x86/entry/common.c:77 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 __slab_free+0x35e/0x410 mm/slub.c:3722 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x1ea/0x590 security/tomoyo/file.c:723 security_file_ioctl+0x70/0xa0 security/security.c:2647 __do_sys_ioctl fs/ioctl.c:865 [inline] __se_sys_ioctl+0x48/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff888026027f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888026027f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888026028000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888026028080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888026028100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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