================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:625 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x130/0xf14 kernel/locking/mutex.c:821 Read of size 8 at addr ffff0000c88504f8 by task kworker/u8:0/12 CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 Workqueue: usbip_event event_handler Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_address_description+0xb0/0x238 mm/kasan/report.c:378 print_report+0x68/0x84 mm/kasan/report.c:482 kasan_report+0x8c/0xc4 mm/kasan/report.c:595 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381 __mutex_lock_common kernel/locking/mutex.c:625 [inline] __mutex_lock+0x130/0xf14 kernel/locking/mutex.c:821 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874 event_handler+0x1d4/0x460 drivers/usb/usbip/usbip_event.c:73 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0x788/0x10b8 kernel/workqueue.c:3405 worker_thread+0x798/0xbd0 kernel/workqueue.c:3486 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 Allocated by task 1: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_alloc_info+0x44/0x54 mm/kasan/generic.c:570 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5334 [inline] __kmalloc_noprof+0x340/0x6b8 mm/slub.c:5359 _kmalloc_noprof include/linux/slab.h:992 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] __usb_create_hcd+0x70/0x7ec drivers/usb/core/hcd.c:2566 usb_create_hcd+0x3c/0x50 drivers/usb/core/hcd.c:2662 vhci_hcd_probe+0x108/0x3b4 drivers/usb/usbip/vhci_hcd.c:1378 platform_probe+0x100/0x1a4 drivers/base/platform.c:1439 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x29c/0x800 drivers/base/dd.c:706 __driver_probe_device+0x1e0/0x350 drivers/base/dd.c:868 driver_probe_device+0x6c/0x19c drivers/base/dd.c:898 __device_attach_driver+0x198/0x2f8 drivers/base/dd.c:1026 bus_for_each_drv+0x144/0x1dc drivers/base/bus.c:500 __device_attach+0x248/0x390 drivers/base/dd.c:1098 device_initial_probe+0x90/0xc8 drivers/base/dd.c:1153 bus_probe_device+0x58/0x120 drivers/base/bus.c:620 device_add+0x6cc/0x9e0 drivers/base/core.c:3772 platform_device_add+0x3dc/0x6f0 drivers/base/platform.c:762 platform_device_register_full+0x4fc/0x5ac drivers/base/platform.c:902 vhci_hcd_init+0x1b0/0x2ec drivers/usb/usbip/vhci_hcd.c:1557 do_one_initcall+0x274/0xc38 init/main.c:1347 do_initcall_level+0x12c/0x1c4 init/main.c:1409 do_initcalls+0x70/0xd0 init/main.c:1425 do_basic_setup+0x7c/0x90 init/main.c:1445 kernel_init_freeable+0x268/0x3a8 init/main.c:1658 kernel_init+0x24/0x1dc init/main.c:1548 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 Freed by task 6744: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_free_info+0x58/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x74/0xa4 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x188/0x690 mm/slub.c:6692 hcd_release drivers/usb/core/hcd.c:2690 [inline] kref_put include/linux/kref.h:65 [inline] usb_put_hcd+0x124/0x16c drivers/usb/core/hcd.c:2704 vhci_hcd_remove+0xd8/0xfc drivers/usb/usbip/vhci_hcd.c:1434 platform_remove+0x6c/0x88 drivers/base/platform.c:1456 device_remove+0xc4/0x134 drivers/base/dd.c:616 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x124/0x20c drivers/base/dd.c:1372 device_driver_detach+0x48/0x58 drivers/base/dd.c:1408 unbind_store+0xc0/0xf0 drivers/base/bus.c:244 drv_attr_store+0x80/0xa4 drivers/base/bus.c:125 sysfs_kf_write+0xe0/0x108 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x260/0x3b8 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x51c/0xa0c fs/read_write.c:687 ksys_write+0x12c/0x228 fs/read_write.c:739 __do_sys_write fs/read_write.c:750 [inline] __se_sys_write fs/read_write.c:747 [inline] __arm64_sys_write+0x84/0x98 fs/read_write.c:747 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 Last potentially related work creation: kasan_save_stack+0x40/0x6c mm/kasan/common.c:57 kasan_record_aux_stack+0xb0/0xc8 mm/kasan/generic.c:556 insert_work+0x54/0x1a0 kernel/workqueue.c:2226 __queue_work+0xdd8/0x1440 kernel/workqueue.c:2401 queue_work_on+0xc0/0x130 kernel/workqueue.c:2452 queue_work include/linux/workqueue.h:699 [inline] usb_hcd_giveback_urb+0x29c/0x350 drivers/usb/core/hcd.c:-1 usb_rh_urb_dequeue drivers/usb/core/hcd.c:845 [inline] unlink1+0x244/0x2e8 drivers/usb/core/hcd.c:1580 usb_hcd_unlink_urb+0xe4/0x1dc drivers/usb/core/hcd.c:1617 usb_kill_urb+0x108/0x31c drivers/usb/core/urb.c:716 hub_quiesce+0x1c0/0x29c drivers/usb/core/hub.c:1412 hub_suspend+0x6b8/0x858 drivers/usb/core/hub.c:4008 usb_suspend_interface drivers/usb/core/driver.c:1323 [inline] usb_suspend_both+0x2e8/0x918 drivers/usb/core/driver.c:1446 usb_runtime_suspend+0x5c/0x110 drivers/usb/core/driver.c:2000 __rpm_callback+0x124/0x2f8 drivers/base/power/runtime.c:406 rpm_callback+0x70/0x1a0 drivers/base/power/runtime.c:460 rpm_suspend+0x43c/0xf74 drivers/base/power/runtime.c:698 __pm_runtime_suspend+0xf8/0x144 drivers/base/power/runtime.c:1167 pm_runtime_autosuspend include/linux/pm_runtime.h:415 [inline] usb_runtime_idle+0x78/0x8c drivers/usb/core/driver.c:2037 rpm_idle+0x354/0x7c4 drivers/base/power/runtime.c:550 pm_runtime_work+0x104/0x194 drivers/base/power/runtime.c:995 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0x788/0x10b8 kernel/workqueue.c:3405 worker_thread+0x798/0xbd0 kernel/workqueue.c:3486 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 Second to last potentially related work creation: kasan_save_stack+0x40/0x6c mm/kasan/common.c:57 kasan_record_aux_stack+0xb0/0xc8 mm/kasan/generic.c:556 insert_work+0x54/0x1a0 kernel/workqueue.c:2226 __queue_work+0xdd8/0x1440 kernel/workqueue.c:2401 queue_work_on+0xc0/0x130 kernel/workqueue.c:2452 queue_work include/linux/workqueue.h:699 [inline] usb_hcd_giveback_urb+0x29c/0x350 drivers/usb/core/hcd.c:-1 rh_call_control drivers/usb/core/hcd.c:706 [inline] rh_urb_enqueue drivers/usb/core/hcd.c:817 [inline] usb_hcd_submit_urb+0xedc/0x169c drivers/usb/core/hcd.c:1538 usb_submit_urb+0xd44/0x1458 drivers/usb/core/urb.c:586 usb_start_wait_urb+0x104/0x478 drivers/usb/core/message.c:62 usb_internal_control_msg drivers/usb/core/message.c:117 [inline] usb_control_msg+0x1e8/0x378 drivers/usb/core/message.c:167 get_port_status drivers/usb/core/hub.c:607 [inline] hub_ext_port_status+0x158/0x578 drivers/usb/core/hub.c:624 usb_hub_port_status drivers/usb/core/hub.c:674 [inline] hub_activate+0x59c/0x15c4 drivers/usb/core/hub.c:1185 hub_init_func2+0x24/0x34 drivers/usb/core/hub.c:1368 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0x788/0x10b8 kernel/workqueue.c:3405 worker_thread+0x798/0xbd0 kernel/workqueue.c:3486 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 The buggy address belongs to the object at ffff0000c8850000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 1272 bytes inside of freed 8192-byte region [ffff0000c8850000, ffff0000c8852000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x108850 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 05ffc00000000040 ffff0000c0002280 dead000000000122 0000000000000000 raw: 0000000000000000 0000000800020002 00000000f5000000 0000000000000000 head: 05ffc00000000040 ffff0000c0002280 dead000000000122 0000000000000000 head: 0000000000000000 0000000800020002 00000000f5000000 0000000000000000 head: 05ffc00000000003 fffffdffc3221401 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000c8850380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c8850400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000c8850480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000c8850500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c8850580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Unable to handle kernel paging request at virtual address dfff800000000200 KASAN: probably user-memory-access in range [0x0000000000001000-0x0000000000001007] Mem abort info: ESR = 0x0000000096000005 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x05: level 1 translation fault Data abort info: ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0 [dfff800000000200] address between user and kernel address ranges Internal error: Oops: 0000000096000005 [#1] SMP Modules linked in: CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Tainted: G B syzkaller #0 PREEMPT Tainted: [B]=BAD_PAGE Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 Workqueue: usbip_event event_handler pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : dev_driver_string drivers/base/core.c:2473 [inline] pc : __dev_printk+0xec/0x198 drivers/base/core.c:5020 lr : dev_bus_name include/linux/device.h:947 [inline] lr : dev_driver_string drivers/base/core.c:2473 [inline] lr : __dev_printk+0xe8/0x198 drivers/base/core.c:5020 sp : ffff80008ec57920 x29: ffff80008ec57920 x28: ffff0000c8850530 x27: 1fffe0001910a0a6 x26: 1fffe0001910a0a8 x25: ffff0000c8850540 x24: dfff800000000000 x23: ffff0000d78cee28 x22: 0000000000000036 x21: 0000000000001000 x20: ffff0000d78cedc0 x19: ffff80008ec579c0 x18: 1fffe00035bc5428 x17: 0000000000000003 x16: ffff800088b07000 x15: ffff800088bbd0a0 x14: ffff0001ade2a14c x13: 0000000000000004 x12: 0000000000000000 x11: ffff80008ec579a0 x10: ffff80008ec579c8 x9 : 0000000000000000 x8 : 0000000000000200 x7 : 0000000000000000 x6 : ffff8000836ef524 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000020 x2 : 0000000000000000 x1 : ffff0000c19e8000 x0 : 0000000000000000 Call trace: dev_driver_string drivers/base/core.c:2473 [inline] (P) __dev_printk+0xec/0x198 drivers/base/core.c:5020 (P) _dev_info+0xfc/0x158 drivers/base/core.c:5065 vhci_shutdown_connection+0x178/0x524 drivers/usb/usbip/vhci_hcd.c:1059 event_handler+0x230/0x460 drivers/usb/usbip/usbip_event.c:79 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0x788/0x10b8 kernel/workqueue.c:3405 worker_thread+0x798/0xbd0 kernel/workqueue.c:3486 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 Code: 97859d89 14000002 97859d87 d343fea8 (38786908) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 97859d89 bl 0xfffffffffe167624 4: 14000002 b 0xc 8: 97859d87 bl 0xfffffffffe167624 c: d343fea8 lsr x8, x21, #3 * 10: 38786908 ldrb w8, [x8, x24] <-- trapping instruction