==================================================================
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 ffff88811154ca00 by task syz-executor/279

CPU: 1 PID: 279 Comm: syz-executor Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 __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
 sk_reset_timer+0x22/0xb0 net/core/sock.c:3398
 inet_csk_reset_xmit_timer include/net/inet_connection_sock.h:-1 [inline]
 tcp_reset_xmit_timer include/net/tcp.h:1366 [inline]
 tcp_rearm_rto+0x312/0x700 net/ipv4/tcp_input.c:3264
 tcp_event_new_data_sent+0x250/0x400 net/ipv4/tcp_output.c:82
 tcp_write_xmit+0x1760/0x6000 net/ipv4/tcp_output.c:2728
 __tcp_push_pending_frames+0x9c/0x2f0 net/ipv4/tcp_output.c:2906
 tcp_push+0x48f/0x660 net/ipv4/tcp.c:738
 tcp_sendmsg_locked+0x3395/0x3a90 net/ipv4/tcp.c:1464
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1492
 inet_sendmsg+0xb6/0xd0 net/ipv4/af_inet.c:841
 sock_sendmsg_nosec net/socket.c:716 [inline]
 __sock_sendmsg net/socket.c:728 [inline]
 sock_write_iter+0x2ee/0x3f0 net/socket.c:1133
 call_write_iter include/linux/fs.h:2282 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x603/0xce0 fs/read_write.c:584
 ksys_write+0x149/0x250 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:646
 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 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: 0033:0x7f953b957f57
Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd66415c80 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000055556ee59500 RCX: 00007f953b957f57
RDX: 00000000000000c0 RSI: 00007f95357fff40 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000c0
R13: 000055556ee6df30 R14: 00007ffd66416220 R15: 00007f95357fff40
 </TASK>

Allocated by task 10950:
 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 10950:
 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_dev_put include/net/bluetooth/hci_core.h:1465 [inline]
 hci_dev_cmd+0x279/0x740 net/bluetooth/hci_core.c:795
 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

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 ffff88811154c000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 2560 bytes inside of
 8192-byte region [ffff88811154c000, ffff88811154e000)

The buggy address belongs to the physical page:
page:ffffea0004455200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x111548
head:ffffea0004455200 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 ffffea0004402400 dead000000000006 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 9838, tgid 9825 (syz.3.3032), ts 644064047368, free_ts 644033870222
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2672
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2679
 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4585
 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5926
 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]
 seq_buf_alloc fs/seq_file.c:38 [inline]
 traverse+0x463/0x560 fs/seq_file.c:138
 seq_read_iter+0xcf2/0xdd0 fs/seq_file.c:195
 seq_read+0x171/0x210 fs/seq_file.c:162
 pde_read fs/proc/inode.c:316 [inline]
 proc_reg_read+0x1e4/0x2d0 fs/proc/inode.c:328
 do_loop_readv_writev fs/read_write.c:756 [inline]
 do_iter_read+0x4c5/0xb40 fs/read_write.c:798
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1580 [inline]
 free_pcp_prepare mm/page_alloc.c:1654 [inline]
 free_unref_page_prepare+0x7f8/0x800 mm/page_alloc.c:3620
 free_unref_page+0x95/0x540 mm/page_alloc.c:3718
 free_the_page mm/page_alloc.c:863 [inline]
 __free_pages+0x67/0x100 mm/page_alloc.c:6016
 __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]
 slab_alloc mm/slub.c:3392 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3399 [inline]
 kmem_cache_alloc+0x16e/0x330 mm/slub.c:3408
 getname_flags+0xb9/0x500 fs/namei.c:139
 user_path_at_empty+0x30/0x1c0 fs/namei.c:2911
 user_path_at include/linux/namei.h:57 [inline]
 inotify_find_inode fs/notify/inotify/inotify_user.c:378 [inline]
 __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:779 [inline]
 __se_sys_inotify_add_watch+0x1bc/0xf20 fs/notify/inotify/inotify_user.c:730

Memory state around the buggy address:
 ffff88811154c900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811154c980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811154ca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88811154ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811154cb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================