================================================================== 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 ffff888118044a00 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.134-syzkaller-00022-gb07be5e5113b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x71/0x210 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:427 kasan_report+0x122/0x150 mm/kasan/report.c:531 __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:624 __do_softirq kernel/softirq.c:662 [inline] invoke_softirq kernel/softirq.c:479 [inline] __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:711 irq_exit_rcu+0x9/0x10 kernel/softirq.c:723 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:default_idle+0xf/0x20 arch/x86/kernel/process.c:736 Code: e9 47 ff ff ff 00 00 cc cc 00 00 90 90 90 90 90 90 90 90 90 90 90 b8 0c 67 40 a5 55 48 89 e5 66 90 0f 00 2d 83 ba 56 00 fb f4 <5d> c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 90 90 90 90 90 RSP: 0018:ffffffff86e07d58 EFLAGS: 00000257 RAX: ffff8881f7000000 RBX: ffffffff86e1c500 RCX: 2816d9c07f66d200 RDX: 0000000000000001 RSI: ffffffff85a9f780 RDI: ffffffff85a9f740 RBP: ffffffff86e07d58 R08: dffffc0000000000 R09: ffffed103ee068ff R10: 0000000000000000 R11: ffffffff84ef7b70 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff86e1c500 R15: dffffc0000000000 arch_cpu_idle+0x1c/0x20 arch/x86/kernel/process.c:727 default_idle_call+0x71/0x1d0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1a7/0x520 kernel/sched/idle.c:303 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:401 rest_init+0x10a/0x130 init/main.c:731 arch_call_rest_init+0xe/0x10 init/main.c:891 start_kernel+0x47d/0x4eb init/main.c:1138 x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:555 x86_64_start_kernel+0x7c/0x81 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0xce/0xdb Allocated by task 16177: 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:2435 hci_alloc_dev include/net/bluetooth/hci_core.h:1484 [inline] hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:636 [inline] hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:712 [inline] hci_uart_tty_ioctl+0x3c8/0xa00 drivers/bluetooth/hci_ldisc.c:765 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 16170: 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+0x13ad/0x1500 net/bluetooth/hci_core.c:2763 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_free_dev+0x1c/0x20 net/bluetooth/hci_core.c:2558 hci_uart_tty_close+0x1a3/0x230 drivers/bluetooth/hci_ldisc.c:552 tty_ldisc_close drivers/tty/tty_ldisc.c:456 [inline] tty_ldisc_kill+0x10f/0x1f0 drivers/tty/tty_ldisc.c:608 tty_ldisc_release+0x1a5/0x200 drivers/tty/tty_ldisc.c:776 tty_release_struct+0x29/0xe0 drivers/tty/tty_io.c:1689 tty_release+0xbfd/0x1210 drivers/tty/tty_io.c:1860 __fput+0x1fc/0x8f0 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x1db/0x240 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+0x5a/0xa0 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 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:2299 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2446 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 ffff888118044000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2560 bytes inside of 8192-byte region [ffff888118044000, ffff888118046000) The buggy address belongs to the physical page: page:ffffea0004601000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x118040 head:ffffea0004601000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 ffffea0005016e00 dead000000000003 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 24618, tgid 24616 (syz.3.5601), ts 1622658424217, free_ts 1622656747600 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2637 prep_new_page+0x1c/0x110 mm/page_alloc.c:2644 get_page_from_freelist+0x2c6e/0x2ce0 mm/page_alloc.c:4539 __alloc_pages+0x19e/0x3a0 mm/page_alloc.c:5842 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+0xa1/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x294/0x480 mm/util.c:592 kvmalloc include/linux/slab.h:716 [inline] kvmalloc_array include/linux/slab.h:734 [inline] __ptr_ring_init_queue_alloc include/linux/ptr_ring.h:471 [inline] ptr_ring_resize include/linux/ptr_ring.h:594 [inline] tun_attach+0x845/0x1460 drivers/net/tun.c:791 tun_net_init+0x44b/0x5a0 drivers/net/tun.c:1007 register_netdevice+0x3f4/0x14a0 net/core/dev.c:10086 tun_set_iff+0x82a/0xe90 drivers/net/tun.c:2851 __tun_chr_ioctl+0x806/0x1e70 drivers/net/tun.c:3114 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1545 [inline] free_pcp_prepare mm/page_alloc.c:1619 [inline] free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3581 free_unref_page+0x8f/0x530 mm/page_alloc.c:3677 free_the_page mm/page_alloc.c:830 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:5931 __free_slab+0xca/0x1a0 mm/slub.c:2039 free_slab mm/slub.c:2054 [inline] discard_slab+0x29/0x40 mm/slub.c:2060 __slab_free+0x201/0x280 mm/slub.c:3599 do_slab_free mm/slub.c:3640 [inline] ___cache_free+0xbf/0xd0 mm/slub.c:3696 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0xc6/0x140 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:310 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:3421 [inline] kmem_cache_alloc_node+0x181/0x340 mm/slub.c:3468 __alloc_skb+0xdf/0x7e0 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1290 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1184 [inline] netlink_sendmsg+0x626/0xbc0 net/netlink/af_netlink.c:1835 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] ____sys_sendmsg+0x5a9/0x990 net/socket.c:2509 ___sys_sendmsg+0x21c/0x290 net/socket.c:2563 Memory state around the buggy address: ffff888118044900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888118044980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888118044a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888118044a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888118044b00: 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: 0 Comm: swapper/0 Tainted: G B 6.1.134-syzkaller-00022-gb07be5e5113b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__queue_work+0x575/0xd30 kernel/workqueue.c:-1 Code: 39 2b 0f 84 b9 00 00 00 e8 58 ce 28 00 4c 89 ff e8 30 8d a8 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 ac 1f 6d 00 49 8b 7d 00 e8 13 89 RSP: 0018:ffffc90000007c70 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 000000007fffffff RCX: ffffffff86e1c500 RDX: 0000000000000100 RSI: 000000007fffffff RDI: 000000007fffffff RBP: ffffc90000007d08 R08: fffffffffffffffb R09: 0000000000000007 R10: ffffed1023008939 R11: 1ffff11023008939 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff8881180449c8 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0df1571da0 CR3: 00000001253c5000 CR4: 00000000003506b0 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:624 __do_softirq kernel/softirq.c:662 [inline] invoke_softirq kernel/softirq.c:479 [inline] __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:711 irq_exit_rcu+0x9/0x10 kernel/softirq.c:723 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:default_idle+0xf/0x20 arch/x86/kernel/process.c:736 Code: e9 47 ff ff ff 00 00 cc cc 00 00 90 90 90 90 90 90 90 90 90 90 90 b8 0c 67 40 a5 55 48 89 e5 66 90 0f 00 2d 83 ba 56 00 fb f4 <5d> c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 90 90 90 90 90 RSP: 0018:ffffffff86e07d58 EFLAGS: 00000257 RAX: ffff8881f7000000 RBX: ffffffff86e1c500 RCX: 2816d9c07f66d200 RDX: 0000000000000001 RSI: ffffffff85a9f780 RDI: ffffffff85a9f740 RBP: ffffffff86e07d58 R08: dffffc0000000000 R09: ffffed103ee068ff R10: 0000000000000000 R11: ffffffff84ef7b70 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff86e1c500 R15: dffffc0000000000 arch_cpu_idle+0x1c/0x20 arch/x86/kernel/process.c:727 default_idle_call+0x71/0x1d0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1a7/0x520 kernel/sched/idle.c:303 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:401 rest_init+0x10a/0x130 init/main.c:731 arch_call_rest_init+0xe/0x10 init/main.c:891 start_kernel+0x47d/0x4eb init/main.c:1138 x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:555 x86_64_start_kernel+0x7c/0x81 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0xce/0xdb 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 58 ce 28 00 4c 89 ff e8 30 8d a8 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 ac 1f 6d 00 49 8b 7d 00 e8 13 89 RSP: 0018:ffffc90000007c70 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 000000007fffffff RCX: ffffffff86e1c500 RDX: 0000000000000100 RSI: 000000007fffffff RDI: 000000007fffffff RBP: ffffc90000007d08 R08: fffffffffffffffb R09: 0000000000000007 R10: ffffed1023008939 R11: 1ffff11023008939 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff8881180449c8 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0df1571da0 CR3: 00000001253c5000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: e9 47 ff ff ff jmp 0xffffff4c 5: 00 00 add %al,(%rax) 7: cc int3 8: cc int3 9: 00 00 add %al,(%rax) b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: b8 0c 67 40 a5 mov $0xa540670c,%eax 1b: 55 push %rbp 1c: 48 89 e5 mov %rsp,%rbp 1f: 66 90 xchg %ax,%ax 21: 0f 00 2d 83 ba 56 00 verw 0x56ba83(%rip) # 0x56baab 28: fb sti 29: f4 hlt * 2a: 5d pop %rbp <-- trapping instruction 2b: c3 ret 2c: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 33: 00 00 00 36: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop