syz-executor: attempt to access beyond end of device loop0: rw=2049, sector=45096, nr_sectors = 8 limit=40427 ================================================================== BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:884 [inline] BUG: KASAN: use-after-free in detach_timer kernel/time/timer.c:886 [inline] BUG: KASAN: use-after-free in detach_if_pending+0x156/0x300 kernel/time/timer.c:905 Write of size 8 at addr ffff88811b7589f8 by task syz-executor/283 CPU: 1 PID: 283 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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_del include/linux/list.h:884 [inline] detach_timer kernel/time/timer.c:886 [inline] detach_if_pending+0x156/0x300 kernel/time/timer.c:905 del_timer+0x75/0xb0 kernel/time/timer.c:1330 try_to_grab_pending+0xcd/0x5d0 kernel/workqueue.c:1285 mod_delayed_work_on+0x44/0xe0 kernel/workqueue.c:1745 mod_delayed_work include/linux/workqueue.h:540 [inline] wb_queue_work+0x2a4/0x3b0 fs/fs-writeback.c:171 bdi_split_work_to_wbs+0x4f1/0xa60 fs/fs-writeback.c:1000 __writeback_inodes_sb_nr+0x219/0x280 fs/fs-writeback.c:2669 writeback_inodes_sb_nr fs/fs-writeback.c:2687 [inline] writeback_inodes_sb+0x74/0x80 fs/fs-writeback.c:2702 sync_filesystem+0xaa/0x260 fs/sync.c:54 generic_shutdown_super+0x6e/0x370 fs/super.c:476 kill_block_super+0x7f/0xf0 fs/super.c:1472 kill_f2fs_super+0x303/0x3b0 fs/f2fs/super.c:4864 deactivate_locked_super+0xb5/0x120 fs/super.c:334 deactivate_super+0xaf/0xe0 fs/super.c:365 cleanup_mnt+0x474/0x500 fs/namespace.c:1191 __cleanup_mnt+0x19/0x20 fs/namespace.c:1198 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:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f0a9719bf17 Code: a2 c7 05 7c 96 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffe27a09a58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f0a9720471f RCX: 00007f0a9719bf17 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe27a09b10 RBP: 00007ffe27a09b10 R08: 00007ffe27a0ab10 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe27a0aba0 R13: 00007f0a9720471f R14: 0000000000015cdd R15: 00007ffe27a0abe0 Allocated by task 881: 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: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+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 881: 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: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:1194 sock_ioctl+0x4ca/0x720 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+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+0x35b/0x740 net/bluetooth/hci_core.c:749 hci_sock_ioctl+0x41e/0x7f0 net/bluetooth/hci_sock.c:1096 sock_do_ioctl+0x114/0x330 net/socket.c:1194 sock_ioctl+0x4ca/0x720 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+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 ffff88811b758000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2552 bytes inside of 8192-byte region [ffff88811b758000, ffff88811b75a000) The buggy address belongs to the physical page: page:ffffea00046dd600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88811b75c000 pfn:0x11b758 head:ffffea00046dd600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 ffffea0004262608 ffffea0004748808 ffff888100043500 raw: ffff88811b75c000 0000000000020001 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 529, tgid 528 (syz.4.51), ts 38952255390, free_ts 38867336762 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+0x2d12/0x2d80 mm/page_alloc.c:4554 __alloc_pages+0x1d9/0x480 mm/page_alloc.c:5868 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_track_caller+0xa0/0x1e0 mm/slab_common.c:958 __do_krealloc mm/slab_common.c:1341 [inline] krealloc+0x6f/0x110 mm/slab_common.c:1374 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:12340 [inline] do_check+0x2e34/0xf070 kernel/bpf/verifier.c:12455 do_check_common+0x11ae/0x1950 kernel/bpf/verifier.c:14934 do_check_main kernel/bpf/verifier.c:14997 [inline] bpf_check+0x3f98/0x10d10 kernel/bpf/verifier.c:15574 bpf_prog_load+0x10f0/0x16a0 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_pcp_prepare mm/page_alloc.c:1625 [inline] free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3589 free_unref_page+0x95/0x540 mm/page_alloc.c:3687 free_the_page mm/page_alloc.c:836 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:5957 __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: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:3382 [inline] slab_alloc mm/slub.c:3392 [inline] __kmem_cache_alloc_lru mm/slub.c:3399 [inline] kmem_cache_alloc_lru+0x104/0x280 mm/slub.c:3415 alloc_inode_sb include/linux/fs.h:3263 [inline] sock_alloc_inode+0x28/0xc0 net/socket.c:304 alloc_inode fs/inode.c:264 [inline] new_inode_pseudo+0x70/0x1f0 fs/inode.c:1073 sock_alloc net/socket.c:629 [inline] __sock_create+0x12c/0x7c0 net/socket.c:1504 Memory state around the buggy address: ffff88811b758880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811b758900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88811b758980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88811b758a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811b758a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================