================================================================== BUG: KASAN: slab-use-after-free in vhci_send_cmd_submit drivers/usb/usbip/vhci_tx.c:69 [inline] BUG: KASAN: slab-use-after-free in vhci_tx_loop+0x3e9/0x1c70 drivers/usb/usbip/vhci_tx.c:241 Read of size 8 at addr ffff8880358be720 by task vhci_tx/25102 CPU: 1 UID: 0 PID: 25102 Comm: vhci_tx Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595[ 815.569811][T25102] kasan_report+0x117/0x150 vhci_send_cmd_submit drivers/usb/usbip/vhci_tx.c:69 [inline] vhci_tx_loop+0x3e9/0x1c70 drivers/usb/usbip/vhci_tx.c:241 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 9: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x3d2/0x6b0 mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] vhci_tx_urb drivers/usb/usbip/vhci_hcd.c:674 [inline] vhci_urb_enqueue+0x5c2/0xe00 drivers/usb/usbip/vhci_hcd.c:829 usb_hcd_submit_urb+0x322/0x1b40 drivers/usb/core/hcd.c:1542 usb_start_wait_urb+0x13f/0x5b0 drivers/usb/core/message.c:62 usb_internal_control_msg drivers/usb/core/message.c:117 [inline] usb_control_msg+0x234/0x3e0 drivers/usb/core/message.c:167 get_bMaxPacketSize0 drivers/usb/core/hub.c:4859 [inline] hub_port_init+0xb0b/0x28b0 drivers/usb/core/hub.c:5055 hub_port_connect drivers/usb/core/hub.c:5504 [inline] hub_port_connect_change drivers/usb/core/hub.c:5715 [inline] port_event drivers/usb/core/hub.c:5879 [inline] hub_event+0x24e2/0x4cf0 drivers/usb/core/hub.c:5961 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 25101: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 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+0x1c5/0x6c0 mm/slub.c:6692 pickup_urb_and_free_priv+0x225/0x3f0 drivers/usb/usbip/vhci_rx.c:46 vhci_recv_ret_submit drivers/usb/usbip/vhci_rx.c:65 [inline] vhci_rx_pdu drivers/usb/usbip/vhci_rx.c:242 [inline] vhci_rx_loop+0x3c5/0xa00 drivers/usb/usbip/vhci_rx.c:265 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff8880358be700 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 32 bytes inside of freed 64-byte region [ffff8880358be700, ffff8880358be740) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x358be flags: 0x80000000000000(node=0|zone=1) page_type: f5(slab) raw: 0080000000000000 ffff88813ffb18c0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800200020 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 28191739539, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x262a/0x26a0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab+0x79/0x5e0 mm/slub.c:3380 new_slab mm/slub.c:3426 [inline] refill_objects+0x2d8/0x350 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] __kmalloc_cache_noprof+0x468/0x6b0 mm/slub.c:5485 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] add_sysfs_param+0x6e0/0xb80 kernel/params.c:636 kernel_add_sysfs_param+0x7f/0xe0 kernel/params.c:797 param_sysfs_builtin+0x199/0x250 kernel/params.c:836 param_sysfs_builtin_init+0x23/0x30 kernel/params.c:972 do_one_initcall+0x250/0x870 init/main.c:1347 do_initcall_level+0x10a/0x1a0 init/main.c:1409 do_initcalls+0x59/0xa0 init/main.c:1425 kernel_init_freeable+0x29d/0x3e0 init/main.c:1658 kernel_init+0x1d/0x1d0 init/main.c:1548 page_owner free stack trace missing Memory state around the buggy address: ffff8880358be600: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ffff8880358be680: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc >ffff8880358be700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff8880358be780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880358be800: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ==================================================================