================================================================== 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+0x3e9/0x1c50 drivers/usb/usbip/vhci_tx.c:241 Read of size 8 at addr ffff888025a4b720 by task vhci_tx/16998 CPU: 1 UID: 0 PID: 16998 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 04/18/2026 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+0x3e9/0x1c50 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+0x3a6/0x690 mm/slub.c:5419 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] vhci_tx_urb drivers/usb/usbip/vhci_hcd.c:674 [inline] vhci_urb_enqueue+0x5c9/0xe10 drivers/usb/usbip/vhci_hcd.c:829 usb_hcd_submit_urb+0x323/0x1b50 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+0xb1e/0x28c0 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+0x25d3/0x4f60 drivers/usb/core/hub.c:5953 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 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 16997: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 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:2689 [inline] slab_free mm/slub.c:6250 [inline] kfree+0x1c5/0x6c0 mm/slub.c:6565 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 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 ffff888025a4b700 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 32 bytes inside of freed 64-byte region [ffff888025a4b700, ffff888025a4b740) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25a4b flags: 0x80000000000000(node=0|zone=1) page_type: f5(slab) raw: 0080000000000000 ffff88801a0108c0 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 1, tgid 1 (swapper/0), ts 21068060516, free_ts 21067304845 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0x27c8/0x2840 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab+0x77/0x660 mm/slub.c:3467 new_slab mm/slub.c:3525 [inline] refill_objects+0x33c/0x3d0 mm/slub.c:7255 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_noprof+0x530/0x7b0 mm/slub.c:5307 kmalloc_noprof include/linux/slab.h:954 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] tomoyo_get_name+0x20c/0x590 security/tomoyo/memory.c:173 tomoyo_parse_name_union+0xd9/0x130 security/tomoyo/util.c:260 tomoyo_update_mount_acl+0xe9/0x2d0 security/tomoyo/file.c:995 tomoyo_write_file+0xae4/0xc50 security/tomoyo/file.c:1048 tomoyo_write_domain2 security/tomoyo/common.c:1160 [inline] tomoyo_add_entry security/tomoyo/common.c:2177 [inline] tomoyo_supervisor+0x1208/0x1570 security/tomoyo/common.c:2238 tomoyo_audit_mount_log security/tomoyo/mount.c:33 [inline] tomoyo_mount_acl security/tomoyo/mount.c:168 [inline] tomoyo_mount_permission+0x624/0x9d0 security/tomoyo/mount.c:239 security_sb_mount+0xe4/0x320 security/security.c:1088 path_mount+0xbc/0x10e0 fs/namespace.c:4096 init_mount+0xc3/0x110 fs/init.c:42 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] free_unref_folios+0xc50/0x1970 mm/page_alloc.c:3004 folios_put_refs+0x7cb/0x8d0 mm/swap.c:1008 folio_batch_release include/linux/folio_batch.h:101 [inline] truncate_inode_pages_range+0x3e0/0xe30 mm/truncate.c:408 kill_bdev block/bdev.c:91 [inline] blkdev_flush_mapping+0x10c/0x2f0 block/bdev.c:720 blkdev_put_whole block/bdev.c:727 [inline] bdev_release+0x422/0x660 block/bdev.c:1152 blkdev_release+0x15/0x20 block/fops.c:705 __fput+0x461/0xa70 fs/file_table.c:510 task_work_run+0x1d9/0x270 kernel/task_work.c:233 init_flush_fput init/do_mounts.h:41 [inline] mount_root_generic+0x1bf/0x450 init/do_mounts.c:205 prepare_namespace+0x66/0xc0 init/do_mounts.c:484 kernel_init_freeable+0x2ee/0x3e0 init/main.c:1721 kernel_init+0x1d/0x1d0 init/main.c:1593 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888025a4b600: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888025a4b680: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff888025a4b700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff888025a4b780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888025a4b800: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc 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