==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:930 [inline]
BUG: KASAN: use-after-free in enqueue_timer+0xae/0x480 kernel/time/timer.c:611
Write of size 8 at addr ffff88811df4ca00 by task ksoftirqd/0/13
CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
__dump_stack+0x21/0x24 lib/dump_stack.c:88
dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
print_address_description+0x71/0x200 mm/kasan/report.c:316
print_report+0x4a/0x60 mm/kasan/report.c:420
kasan_report+0x122/0x150 mm/kasan/report.c:524
__asan_report_store8_noabort+0x17/0x20 mm/kasan/report_generic.c:356
hlist_add_head include/linux/list.h:930 [inline]
enqueue_timer+0xae/0x480 kernel/time/timer.c:611
internal_add_timer kernel/time/timer.c:640 [inline]
__mod_timer+0x84c/0xc00 kernel/time/timer.c:1137
mod_timer+0x1f/0x30 kernel/time/timer.c:1196
tipc_disc_timeout+0x643/0x860 net/tipc/discover.c:331
call_timer_fn+0x46/0x2a0 kernel/time/timer.c:1553
expire_timers kernel/time/timer.c:1604 [inline]
__run_timers+0x65b/0x9f0 kernel/time/timer.c:1875
run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1888
handle_softirqs+0x1d7/0x600 kernel/softirq.c:642
run_ksoftirqd+0x28/0x30 kernel/softirq.c:1019
smpboot_thread_fn+0x4a0/0x910 kernel/smpboot.c:164
kthread+0x281/0x320 kernel/kthread.c:386
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Allocated by task 3725:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505
____kasan_kmalloc mm/kasan/common.c:380 [inline]
__kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:389
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:1505 [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+0x3c8/0xa20 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:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Freed by task 3723:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516
____kasan_slab_free+0x132/0x180 mm/kasan/common.c:242
__kasan_slab_free+0x11/0x20 mm/kasan/common.c:250
kasan_slab_free include/linux/kasan.h:178 [inline]
slab_free_hook mm/slub.c:1750 [inline]
slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776
slab_free mm/slub.c:3712 [inline]
__kmem_cache_free+0xb7/0x1b0 mm/slub.c:3728
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_free_dev+0x1c/0x20 net/bluetooth/hci_core.c:2556
hci_uart_tty_close+0x1a3/0x230 drivers/bluetooth/hci_ldisc.c:555
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+0x1e1/0x250 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+0x87/0xd0 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:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Last potentially related work creation:
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
__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+0xde/0x150 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+0xa7f/0xd30 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+0x648/0x740 net/bluetooth/hci_core.c:-1
hci_sock_ioctl+0x41e/0x7f0 net/bluetooth/hci_sock.c:1096
sock_do_ioctl+0x114/0x330 net/socket.c:1191
sock_ioctl+0x4bd/0x710 net/socket.c:1310
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:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Second to last potentially related work creation:
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
__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+0xde/0x150 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+0xa29/0x11e0 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 ffff88811df4c000
which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 2560 bytes inside of
8192-byte region [ffff88811df4c000, ffff88811df4e000)
The buggy address belongs to the physical page:
page:ffffea000477d200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11df48
head:ffffea000477d200 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000001 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 2903, tgid 2902 (syz.4.743), ts 135555845951, free_ts 135496014781
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2670
prep_new_page+0x1c/0x110 mm/page_alloc.c:2677
get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4583
__alloc_pages+0x1d9/0x480 mm/page_alloc.c:5897
alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
allocate_slab mm/slub.c:1967 [inline]
new_slab+0x98/0x3d0 mm/slub.c:2020
___slab_alloc+0x6bd/0xb20 mm/slub.c:3177
__slab_alloc+0x5e/0xa0 mm/slub.c:3263
slab_alloc_node mm/slub.c:3348 [inline]
__kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3423
__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+0x28a/0x460 mm/util.c:592
kvmalloc include/linux/slab.h:716 [inline]
kvmalloc_array include/linux/slab.h:734 [inline]
io_pages_map+0x5a/0x5e0 io_uring/io_uring.c:2590
io_allocate_scq_urings+0xf3/0x45a io_uring/io_uring.c:3533
io_uring_create+0x5bd/0xde3 io_uring/io_uring.c:3693
io_uring_setup io_uring/io_uring.c:3791 [inline]
__do_sys_io_uring_setup io_uring/io_uring.c:3797 [inline]
__se_sys_io_uring_setup io_uring/io_uring.c:3794 [inline]
__x64_sys_io_uring_setup+0x21b/0x230 io_uring/io_uring.c:3794
x64_sys_call+0x4ab/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:426
page last free stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
free_pages_prepare mm/page_alloc.c:1578 [inline]
free_pcp_prepare mm/page_alloc.c:1652 [inline]
free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3618
free_unref_page+0x95/0x540 mm/page_alloc.c:3716
free_the_page mm/page_alloc.c:863 [inline]
__free_pages+0x67/0x100 mm/page_alloc.c:5986
__free_slab+0xca/0x1a0 mm/slub.c:2044
free_slab mm/slub.c:2059 [inline]
discard_slab mm/slub.c:2065 [inline]
__unfreeze_partials+0x160/0x190 mm/slub.c:2614
put_cpu_partial+0xa9/0x100 mm/slub.c:2690
__slab_free+0x1c4/0x280 mm/slub.c:3589
do_slab_free mm/slub.c:3666 [inline]
___cache_free+0xbf/0xd0 mm/slub.c:3722
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:311
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:3382 [inline]
__kmem_cache_alloc_node+0x192/0x2c0 mm/slub.c:3423
__do_kmalloc_node mm/slab_common.c:937 [inline]
__kmalloc+0xa1/0x1e0 mm/slab_common.c:951
kmalloc include/linux/slab.h:568 [inline]
inotify_handle_inode_event+0x18f/0x4e0 fs/notify/inotify/inotify_fsnotify.c:96
fsnotify_handle_inode_event fs/notify/fsnotify.c:282 [inline]
fsnotify_handle_event fs/notify/fsnotify.c:337 [inline]
send_to_group fs/notify/fsnotify.c:385 [inline]
fsnotify+0x1ba1/0x1f10 fs/notify/fsnotify.c:591
Memory state around the buggy address:
ffff88811df4c900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88811df4c980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811df4ca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88811df4ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88811df4cb00: 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: 3780 Comm: syz.1.1007 Tainted: G B syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__queue_work+0x575/0xd30 kernel/workqueue.c:-1
Code: 39 2b 0f 84 b9 00 00 00 e8 48 46 29 00 4c 89 ff e8 60 70 b8 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 9c 78 6e 00 49 8b 7d 00 e8 f3 6b
RSP: 0018:ffffc90000007c70 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 000000007fffffff RCX: ffff8881139a3cc0
RDX: 0000000000000100 RSI: 000000007fffffff RDI: 000000007fffffff
RBP: ffffc90000007d08 R08: 0000000000000007 R09: fffffffffffffffb
R10: dffffc0000000000 R11: ffffed1023be9939 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88811df4c9c8 R15: 0000000000000008
FS: 00007f0d572766c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0d57255d58 CR3: 000000011e87c000 CR4: 00000000003506b0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 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:1553
expire_timers kernel/time/timer.c:1599 [inline]
__run_timers+0x689/0x9f0 kernel/time/timer.c:1875
run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1888
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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x55/0x80 kernel/locking/spinlock.c:194
Code: 00 d5 0d 87 e8 ac 07 b6 fc 4c 89 f7 48 83 3d 21 3d 0d 02 00 74 30 e8 9e 0d 00 00 90 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 86 0b 4c fc 65 8b 05 c7 d5 01 7b 85 c0 74 05 5b 41 5e 5d c3 e8
RSP: 0018:ffffc9000766f5a0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000a06 RCX: dffffc0000000000
RDX: ffffc90007887678 RSI: 0000000000000a06 RDI: 0000000000000001
RBP: ffffc9000766f5b0 R08: ffff88811601bcc7 R09: 1ffff11022c03798
R10: dffffc0000000000 R11: ffffed1022c03799 R12: ffff8881323b2c00
R13: 0000000000000010 R14: 0000000000000001 R15: 0000000000000000
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
__wake_up_common_lock kernel/sched/wait.c:141 [inline]
__wake_up_sync_key+0x17b/0x2b0 kernel/sched/wait.c:212
__unix_dgram_recvmsg+0x4c1/0xdc0 net/unix/af_unix.c:2480
unix_dgram_recvmsg+0xc7/0xe0 net/unix/af_unix.c:2550
____sys_recvmsg+0x2d9/0x5f0 net/socket.c:-1
___sys_recvmsg+0x212/0x590 net/socket.c:2769
do_recvmmsg+0x393/0x840 net/socket.c:2863
__sys_recvmmsg net/socket.c:2942 [inline]
__do_sys_recvmmsg net/socket.c:2965 [inline]
__se_sys_recvmmsg net/socket.c:2958 [inline]
__x64_sys_recvmmsg+0x195/0x250 net/socket.c:2958
x64_sys_call+0x3e7/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:300
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0d5639c629
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:00007f0d57276028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f0d56616090 RCX: 00007f0d5639c629
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000008
RBP: 00007f0d56432b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0d56616128 R14: 00007f0d56616090 R15: 00007ffd7d548058
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 48 46 29 00 4c 89 ff e8 60 70 b8 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 9c 78 6e 00 49 8b 7d 00 e8 f3 6b
RSP: 0018:ffffc90000007c70 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 000000007fffffff RCX: ffff8881139a3cc0
RDX: 0000000000000100 RSI: 000000007fffffff RDI: 000000007fffffff
RBP: ffffc90000007d08 R08: 0000000000000007 R09: fffffffffffffffb
R10: dffffc0000000000 R11: ffffed1023be9939 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88811df4c9c8 R15: 0000000000000008
FS: 00007f0d572766c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0d57255d58 CR3: 000000011e87c000 CR4: 00000000003506b0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 39 2b cmp %ebp,(%rbx)
2: 0f 84 b9 00 00 00 je 0xc1
8: e8 48 46 29 00 call 0x294655
d: 4c 89 ff mov %r15,%rdi
10: e8 60 70 b8 03 call 0x3b87075
15: 49 bc 00 00 00 00 00 movabs $0xdffffc0000000000,%r12
1c: fc ff df
1f: 4c 8b 6d d0 mov -0x30(%rbp),%r13
23: 4c 89 e8 mov %r13,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 4c 89 ef mov %r13,%rdi
34: e8 9c 78 6e 00 call 0x6e78d5
39: 49 8b 7d 00 mov 0x0(%r13),%rdi
3d: e8 .byte 0xe8
3e: f3 repz
3f: 6b .byte 0x6b