================================================================== 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 ffff88806f01cda0 by task vhci_tx/16242 CPU: 0 UID: 0 PID: 16242 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 06/25/2026 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 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 822: 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+0x3cd/0x670 mm/slub.c:5486 _kmalloc_noprof include/linux/slab.h:969 [inline] _kzalloc_noprof include/linux/slab.h:1290 [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:4851 [inline] hub_port_init+0xb0b/0x28b0 drivers/usb/core/hub.c:5047 hub_port_connect drivers/usb/core/hub.c:5496 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x24e2/0x4cf0 drivers/usb/core/hub.c:5953 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379 process_scheduled_works kernel/workqueue.c:3462 [inline] worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543 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 16240: 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:2706 [inline] slab_free mm/slub.c:6388 [inline] kfree+0x1c5/0x6c0 mm/slub.c:6703 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 ffff88806f01cd80 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 32 bytes inside of freed 64-byte region [ffff88806f01cd80, ffff88806f01cdc0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6f01c flags: 0x80000000000000(node=0|zone=1) page_type: f5(slab) raw: 0080000000000000 ffff88813feae8c0 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 0xd2c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9606, tgid 9606 (udevd), ts 1181516889705 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x264c/0x26c0 mm/page_alloc.c:3955 __alloc_frozen_pages_noprof+0x222/0x5b0 mm/page_alloc.c:5394 alloc_slab_page mm/slub.c:3295 [inline] allocate_slab+0x7c/0x5e0 mm/slub.c:3410 new_slab mm/slub.c:3456 [inline] refill_objects+0x2d8/0x350 mm/slub.c:7321 refill_sheaf mm/slub.c:2833 [inline] __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4699 alloc_from_pcs mm/slub.c:4775 [inline] slab_alloc_node mm/slub.c:4909 [inline] __do_kmalloc_node mm/slub.c:5338 [inline] __kmalloc_noprof+0x543/0x790 mm/slub.c:5364 _kmalloc_noprof include/linux/slab.h:973 [inline] _kzalloc_noprof include/linux/slab.h:1290 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x2ad/0x570 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x5fa/0x640 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x283/0x560 security/tomoyo/file.c:827 security_inode_getattr+0x121/0x2d0 security/security.c:1895 vfs_getattr fs/stat.c:259 [inline] vfs_fstat fs/stat.c:281 [inline] __do_sys_newfstat fs/stat.c:551 [inline] __se_sys_newfstat fs/stat.c:546 [inline] __x64_sys_newfstat+0x133/0x270 fs/stat.c:546 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x17b/0x530 arch/x86/entry/syscall_64.c:85 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 14026 tgid 14024 ts 1176500547088 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0x1185/0x1270 mm/page_alloc.c:2962 tlb_batch_list_free mm/mmu_gather.c:161 [inline] tlb_finish_mmu+0x13e/0x220 mm/mmu_gather.c:552 exit_mmap+0x4b2/0x9f0 mm/mmap.c:1313 __mmput+0xcb/0x3e0 kernel/fork.c:1186 exit_mm+0x186/0x240 kernel/exit.c:615 do_exit+0x6cd/0x2360 kernel/exit.c:997 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152 get_signal+0x121b/0x12c0 kernel/signal.c:3039 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:339 [inline] do_syscall_64+0x33d/0x530 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88806f01cc80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff88806f01cd00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88806f01cd80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff88806f01ce00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88806f01ce80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================