usb 5-1: USB disconnect, device number 8 ================================================================== BUG: KASAN: slab-use-after-free in hdm_disconnect+0x10d/0x1c0 drivers/most/most_usb.c:1125 Read of size 8 at addr ffff88804863d898 by task kworker/0:7/16641 CPU: 0 PID: 16641 Comm: kworker/0:7 Not tainted 6.6.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x200 mm/kasan/report.c:466 kasan_report+0x117/0x150 mm/kasan/report.c:579 hdm_disconnect+0x10d/0x1c0 drivers/most/most_usb.c:1125 usb_unbind_interface+0x1f2/0x870 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4cb/0x7a0 drivers/base/dd.c:1295 bus_remove_device+0x342/0x400 drivers/base/bus.c:576 device_del+0x50b/0x900 drivers/base/core.c:3872 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1416 usb_disconnect+0x34c/0x8a0 drivers/usb/core/hub.c:2315 hub_port_connect drivers/usb/core/hub.c:5369 [inline] hub_port_connect_change drivers/usb/core/hub.c:5669 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x1cef/0x49c0 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 16641: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] hdm_probe+0x96/0x13e0 drivers/most/most_usb.c:959 usb_probe_interface+0x5a4/0xb00 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb40 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2207 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238 usb_probe_device+0x13d/0x280 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb40 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 usb_new_device+0xa31/0x1630 drivers/usb/core/hub.c:2660 hub_port_connect drivers/usb/core/hub.c:5529 [inline] hub_port_connect_change drivers/usb/core/hub.c:5669 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x2962/0x49c0 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Freed by task 16641: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 device_release+0x96/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x221/0x470 lib/kobject.c:737 hdm_disconnect+0xf3/0x1c0 drivers/most/most_usb.c:1123 usb_unbind_interface+0x1f2/0x870 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4cb/0x7a0 drivers/base/dd.c:1295 bus_remove_device+0x342/0x400 drivers/base/bus.c:576 device_del+0x50b/0x900 drivers/base/core.c:3872 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1416 usb_disconnect+0x34c/0x8a0 drivers/usb/core/hub.c:2315 hub_port_connect drivers/usb/core/hub.c:5369 [inline] hub_port_connect_change drivers/usb/core/hub.c:5669 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x1cef/0x49c0 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 queue_work_on+0x121/0x1e0 kernel/workqueue.c:1835 queue_work include/linux/workqueue.h:562 [inline] hci_req_sync_run net/bluetooth/hci_sync.c:145 [inline] __hci_cmd_sync_sk+0x61d/0xe40 net/bluetooth/hci_sync.c:167 __hci_cmd_sync_status_sk net/bluetooth/hci_sync.c:258 [inline] __hci_cmd_sync_status net/bluetooth/hci_sync.c:282 [inline] hci_read_local_features_sync net/bluetooth/hci_sync.c:3704 [inline] hci_init_stage_sync net/bluetooth/hci_sync.c:3619 [inline] hci_init1_sync net/bluetooth/hci_sync.c:3751 [inline] hci_init_sync net/bluetooth/hci_sync.c:4837 [inline] hci_dev_init_sync net/bluetooth/hci_sync.c:5029 [inline] hci_dev_open_sync+0x1474/0x2b50 net/bluetooth/hci_sync.c:5107 hci_dev_do_open net/bluetooth/hci_core.c:452 [inline] hci_power_on+0x1b5/0x680 net/bluetooth/hci_core.c:953 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 queue_work_on+0x121/0x1e0 kernel/workqueue.c:1835 queue_work include/linux/workqueue.h:562 [inline] hci_register_dev+0x72d/0x890 net/bluetooth/hci_core.c:2665 hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:688 [inline] hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:714 [inline] hci_uart_tty_ioctl+0x822/0x9f0 drivers/bluetooth/hci_ldisc.c:768 tty_ioctl+0x9bd/0xdd0 drivers/tty/tty_io.c:2788 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88804863c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 6296 bytes inside of freed 8192-byte region [ffff88804863c000, ffff88804863e000) The buggy address belongs to the physical page: page:ffffea0001218e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x48638 head:ffffea0001218e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017842280 ffffea00017a1800 dead000000000005 raw: 0000000000000000 0000000080020002 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 29570, tgid 29568 (syz.0.6484), ts 1578419749636, free_ts 1576535489598 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa4/0x230 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] kvmalloc_node+0x70/0x180 mm/util.c:617 kvmalloc include/linux/slab.h:738 [inline] kvmalloc_array include/linux/slab.h:756 [inline] __ptr_ring_init_queue_alloc include/linux/ptr_ring.h:471 [inline] ptr_ring_init include/linux/ptr_ring.h:489 [inline] skb_array_init include/linux/skb_array.h:182 [inline] pfifo_fast_init+0x238/0x6a0 net/sched/sch_generic.c:867 qdisc_create_dflt+0x11e/0x430 net/sched/sch_generic.c:1016 mq_init+0x2e3/0x660 net/sched/sch_mq.c:90 qdisc_create_dflt+0x11e/0x430 net/sched/sch_generic.c:1016 attach_default_qdiscs net/sched/sch_generic.c:1196 [inline] dev_activate+0x1d0/0x11a0 net/sched/sch_generic.c:1250 __dev_open+0x338/0x430 net/core/dev.c:1515 __dev_change_flags+0x20e/0x6a0 net/core/dev.c:8673 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2122 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2662 put_cpu_partial+0x17c/0x250 mm/slub.c:2738 __slab_free+0x31d/0x410 mm/slub.c:3686 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 ____kasan_kmalloc mm/kasan/common.c:340 [inline] __kasan_kmalloc+0x22/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] nsim_fib6_rt_create drivers/net/netdevsim/fib.c:547 [inline] nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:752 [inline] nsim_fib6_event drivers/net/netdevsim/fib.c:856 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:889 [inline] nsim_fib_event_work+0x116f/0x3170 drivers/net/netdevsim/fib.c:1494 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Memory state around the buggy address: ffff88804863d780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804863d800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88804863d880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804863d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804863d980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================