================================================================== BUG: KASAN: use-after-free in hlist_move_list include/linux/list.h:1014 [inline] BUG: KASAN: use-after-free in collect_expired_timers kernel/time/timer.c:1576 [inline] BUG: KASAN: use-after-free in __run_timers+0x32b/0x9a0 kernel/time/timer.c:1812 Write of size 8 at addr ffff888133fb0a00 by task kworker/0:4/383 CPU: 0 PID: 383 Comm: kworker/0:4 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: rcu_gp process_srcu Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x71/0x1e0 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:418 kasan_report+0x122/0x150 mm/kasan/report.c:522 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report_generic.c:356 hlist_move_list include/linux/list.h:1014 [inline] collect_expired_timers kernel/time/timer.c:1576 [inline] __run_timers+0x32b/0x9a0 kernel/time/timer.c:1812 run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1839 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 RIP: 0010:preempt_count_sub+0x1c/0x170 kernel/sched/core.c:5923 Code: 90 90 90 90 90 90 90 90 90 b8 ac 0c 9c 01 55 48 89 e5 41 56 53 48 bb 00 00 00 00 00 fc ff df 48 c7 c0 20 11 97 87 48 c1 e8 03 <0f> b6 04 18 84 c0 0f 85 c2 00 00 00 83 3d d1 72 4b 06 00 75 25 65 RSP: 0018:ffffc9000df07ba8 EFLAGS: 00000a06 RAX: 1ffffffff0f2e224 RBX: dffffc0000000000 RCX: dffffc0000000000 RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001 RBP: ffffc9000df07bb8 R08: 0000000000000004 R09: 0000000000000003 R10: fffff52001be0f6c R11: 1ffff92001be0f6c R12: ffffffff87070498 R13: dffffc0000000000 R14: ffffffff87070400 R15: ffffffff87070450 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x4d/0x70 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] srcu_reschedule+0x93/0xf0 kernel/rcu/srcutree.c:1634 process_srcu+0x6b5/0x11e0 kernel/rcu/srcutree.c:1666 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2449 kthread+0x281/0x320 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 21243: 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_kmalloc mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:388 kasan_kmalloc include/linux/kasan.h:212 [inline] __do_kmalloc_node mm/slab_common.c:938 [inline] __kmalloc+0xb1/0x1e0 mm/slab_common.c:951 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] hci_alloc_dev_priv+0x27/0x1bd0 net/bluetooth/hci_core.c:2433 hci_alloc_dev include/net/bluetooth/hci_core.h:1484 [inline] hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:641 [inline] hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:719 [inline] hci_uart_tty_ioctl+0x3d6/0xa20 drivers/bluetooth/hci_ldisc.c:774 tty_ioctl+0x8ef/0xc60 drivers/tty/tty_io.c:2785 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 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 21243: 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:1745 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1771 slab_free mm/slub.c:3686 [inline] __kmem_cache_free+0xb7/0x1b0 mm/slub.c:3702 kfree+0x6f/0xf0 mm/slab_common.c:990 hci_release_dev+0x12a3/0x13b0 net/bluetooth/hci_core.c:2761 bt_host_release+0x82/0x90 net/bluetooth/hci_sysfs.c:85 device_release+0xa4/0x1d0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:681 [inline] kobject_release lib/kobject.c:712 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x19d/0x280 lib/kobject.c:729 put_device+0x1f/0x30 drivers/base/core.c:3806 hci_dev_put include/net/bluetooth/hci_core.h:1444 [inline] hci_dev_cmd+0x265/0x720 net/bluetooth/hci_core.c:795 hci_sock_ioctl+0x41e/0x7f0 net/bluetooth/hci_sock.c:1096 sock_do_ioctl+0x101/0x310 net/socket.c:1194 sock_ioctl+0x4d8/0x6e0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 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 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 insert_work+0x51/0x300 kernel/workqueue.c:1368 __queue_work+0x9b1/0xd30 kernel/workqueue.c:1527 queue_work_on+0xd2/0x140 kernel/workqueue.c:1555 queue_work include/linux/workqueue.h:510 [inline] hci_cmd_sync_run net/bluetooth/hci_sync.c:140 [inline] __hci_cmd_sync_sk+0xa3e/0xcf0 net/bluetooth/hci_sync.c:162 __hci_cmd_sync_status_sk net/bluetooth/hci_sync.c:253 [inline] __hci_cmd_sync_status net/bluetooth/hci_sync.c:277 [inline] hci_cmd_sync_status+0x53/0x120 net/bluetooth/hci_sync.c:288 hci_dev_cmd+0x628/0x720 net/bluetooth/hci_core.c:-1 hci_sock_ioctl+0x41e/0x7f0 net/bluetooth/hci_sock.c:1096 sock_do_ioctl+0x101/0x310 net/socket.c:1194 sock_ioctl+0x4d8/0x6e0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 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 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 insert_work+0x51/0x300 kernel/workqueue.c:1368 __queue_work+0x9b1/0xd30 kernel/workqueue.c:1527 queue_work_on+0xd2/0x140 kernel/workqueue.c:1555 queue_work include/linux/workqueue.h:510 [inline] hci_cmd_timeout+0x191/0x200 net/bluetooth/hci_core.c:1468 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302 worker_thread+0xa29/0x11f0 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 ffff888133fb0000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2560 bytes inside of 8192-byte region [ffff888133fb0000, ffff888133fb2000) The buggy address belongs to the physical page: page:ffffea0004cfec00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x133fb0 head:ffffea0004cfec00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 ffffea0004197a00 dead000000000005 ffff888100043500 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 1270, tgid 1269 (syz.3.233), ts 126229036790, free_ts 109469139620 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+0x2c7b/0x2cf0 mm/page_alloc.c:4554 __alloc_pages+0x1c3/0x450 mm/page_alloc.c:5868 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1962 [inline] new_slab+0x98/0x3d0 mm/slub.c:2015 ___slab_alloc+0x6f6/0xb50 mm/slub.c:3203 __slab_alloc+0x5e/0xa0 mm/slub.c:3302 slab_alloc_node mm/slub.c:3387 [inline] __kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3462 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc_node_track_caller+0xa0/0x1e0 mm/slab_common.c:958 __do_krealloc mm/slab_common.c:1342 [inline] krealloc+0x6f/0x110 mm/slab_common.c:1375 copy_array kernel/bpf/verifier.c:955 [inline] copy_stack_state kernel/bpf/verifier.c:1009 [inline] copy_func_state kernel/bpf/verifier.c:1130 [inline] copy_verifier_state+0x6bb/0xab0 kernel/bpf/verifier.c:1166 is_state_visited kernel/bpf/verifier.c:12336 [inline] do_check+0x2e2e/0xf060 kernel/bpf/verifier.c:12451 do_check_common+0x11ae/0x1950 kernel/bpf/verifier.c:14930 do_check_main kernel/bpf/verifier.c:14993 [inline] bpf_check+0x3de0/0x10ca0 kernel/bpf/verifier.c:15570 bpf_prog_load+0x1071/0x15a0 kernel/bpf/syscall.c:2621 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1551 [inline] __free_pages_ok+0xb02/0xc10 mm/page_alloc.c:1809 free_the_page mm/page_alloc.c:838 [inline] __free_pages+0xec/0x100 mm/page_alloc.c:5957 free_large_kmalloc+0xae/0xf0 mm/slab_common.c:915 kfree+0x8b/0xf0 mm/slab_common.c:984 skb_free_head net/core/skbuff.c:765 [inline] skb_release_data+0x63f/0x890 net/core/skbuff.c:794 skb_release_all net/core/skbuff.c:859 [inline] __kfree_skb net/core/skbuff.c:873 [inline] kfree_skb_reason+0xd4/0x230 net/core/skbuff.c:896 kfree_skb include/linux/skbuff.h:1239 [inline] tsk_advance_rx_queue+0x10b/0x240 net/tipc/socket.c:281 tipc_recvstream+0x759/0xe80 net/tipc/socket.c:2092 ____sys_recvmsg+0x2a0/0x590 net/socket.c:-1 ___sys_recvmsg+0x1b2/0x510 net/socket.c:2770 __sys_recvmsg net/socket.c:2800 [inline] __do_sys_recvmsg net/socket.c:2810 [inline] __se_sys_recvmsg net/socket.c:2807 [inline] __x64_sys_recvmsg+0x1ed/0x2c0 net/socket.c:2807 x64_sys_call+0x75/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:48 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 Memory state around the buggy address: ffff888133fb0900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888133fb0980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888133fb0a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888133fb0a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888133fb0b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 PID: 383 Comm: kworker/0:4 Tainted: G B syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: rcu_gp process_srcu RIP: 0010:__queue_work+0x575/0xd30 kernel/workqueue.c:-1 Code: 39 2b 0f 84 b9 00 00 00 e8 a8 dd 28 00 4c 89 ff e8 f0 80 ac 03 49 bc 00 00 00 00 00 fc ff df 4c 8b 6d d0 4c 89 e8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ef e8 ec 45 6d 00 49 8b 7d 00 e8 d3 7c RSP: 0018:ffffc90000007c70 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 000000007fffffff RCX: ffff888114cd2880 RDX: 0000000000000100 RSI: 000000007fffffff RDI: 000000007fffffff RBP: ffffc90000007d08 R08: fffffffffffffffb R09: 0000000000000007 R10: ffffed10267f6139 R11: 1ffff110267f6139 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff888133fb09c8 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32522ff8 CR3: 00000001077ec000 CR4: 00000000003526b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: delayed_work_timer_fn+0x61/0x80 kernel/workqueue.c:1653 call_timer_fn+0x46/0x2a0 kernel/time/timer.c:1510 expire_timers kernel/time/timer.c:1550 [inline] __run_timers+0x667/0x9a0 kernel/time/timer.c:1826 run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1839 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 RIP: 0010:preempt_count_sub+0x1c/0x170 kernel/sched/core.c:5923 Code: 90 90 90 90 90 90 90 90 90 b8 ac 0c 9c 01 55 48 89 e5 41 56 53 48 bb 00 00 00 00 00 fc ff df 48 c7 c0 20 11 97 87 48 c1 e8 03 <0f> b6 04 18 84 c0 0f 85 c2 00 00 00 83 3d d1 72 4b 06 00 75 25 65 RSP: 0018:ffffc9000df07ba8 EFLAGS: 00000a06 RAX: 1ffffffff0f2e224 RBX: dffffc0000000000 RCX: dffffc0000000000 RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001 RBP: ffffc9000df07bb8 R08: 0000000000000004 R09: 0000000000000003 R10: fffff52001be0f6c R11: 1ffff92001be0f6c R12: ffffffff87070498 R13: dffffc0000000000 R14: ffffffff87070400 R15: ffffffff87070450 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x4d/0x70 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] srcu_reschedule+0x93/0xf0 kernel/rcu/srcutree.c:1634 process_srcu+0x6b5/0x11e0 kernel/rcu/srcutree.c:1666 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2449 kthread+0x281/0x320 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__queue_work+0x575/0xd30 kernel/workqueue.c:-1 Code: 39 2b 0f 84 b9 00 00 00 e8 a8 dd 28 00 4c 89 ff e8 f0 80 ac 03 49 bc 00 00 00 00 00 fc ff df 4c 8b 6d d0 4c 89 e8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ef e8 ec 45 6d 00 49 8b 7d 00 e8 d3 7c RSP: 0018:ffffc90000007c70 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 000000007fffffff RCX: ffff888114cd2880 RDX: 0000000000000100 RSI: 000000007fffffff RDI: 000000007fffffff RBP: ffffc90000007d08 R08: fffffffffffffffb R09: 0000000000000007 R10: ffffed10267f6139 R11: 1ffff110267f6139 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff888133fb09c8 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32522ff8 CR3: 00000001077ec000 CR4: 00000000003526b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: b8 ac 0c 9c 01 mov $0x19c0cac,%eax e: 55 push %rbp f: 48 89 e5 mov %rsp,%rbp 12: 41 56 push %r14 14: 53 push %rbx 15: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 1c: fc ff df 1f: 48 c7 c0 20 11 97 87 mov $0xffffffff87971120,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 0f b6 04 18 movzbl (%rax,%rbx,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 c2 00 00 00 jne 0xf8 36: 83 3d d1 72 4b 06 00 cmpl $0x0,0x64b72d1(%rip) # 0x64b730e 3d: 75 25 jne 0x64 3f: 65 gs