[syzbot] [usb?] KASAN: slab-use-after-free Read in vhci_shutdown_connection

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f5098b6bae76 Linux 7.2-rc5
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11b391b9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=4e38b15c29e6a1d9
dashboard link: https://syzkaller.appspot.com/bug?extid=31117fde582fe6a0cd62
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1575d1b9580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7d76d25427fa/disk-f5098b6b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b2a3f9e7cb3e/vmlinux-f5098b6b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e4d49cdcd799/bzImage-f5098b6b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+31117f...@syzkaller.appspotmail.com

vhci_hcd vhci_hcd.0: disconnect device
vhci_hcd vhci_hcd.0: stop threads
==================================================================
BUG: KASAN: slab-use-after-free in vhci_shutdown_connection+0x1d4/0x650 drivers/usb/usbip/vhci_hcd.c:1062
Read of size 8 at addr ffff888020bd1560 by task kworker/u8:9/1170

CPU: 1 UID: 0 PID: 1170 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: usbip_event event_handler
Call Trace:
<TASK>
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_shutdown_connection+0x1d4/0x650 drivers/usb/usbip/vhci_hcd.c:1062
event_handler+0x2a4/0x4b0 drivers/usb/usbip/usbip_event.c:79
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
</TASK>

Allocated by task 1:
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]
__do_kmalloc_node mm/slub.c:5334 [inline]
__kmalloc_noprof+0x375/0x720 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
__usb_create_hcd+0x67/0x900 drivers/usb/core/hcd.c:2566
vhci_hcd_probe+0x104/0x3e0 drivers/usb/usbip/vhci_hcd.c:1378
platform_probe+0xf9/0x190 drivers/base/platform.c:1439
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x254/0xae0 drivers/base/dd.c:706
__driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
__device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c4/0x450 drivers/base/dd.c:1098
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
device_add+0x7d7/0xb80 drivers/base/core.c:3772
platform_device_add+0x4bd/0x860 drivers/base/platform.c:762
platform_device_register_full+0x62d/0x710 drivers/base/platform.c:902
vhci_hcd_init+0x227/0x360 drivers/usb/usbip/vhci_hcd.c:1557
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
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 6083:
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+0x1c5/0x640 mm/slub.c:6692
vhci_hcd_remove+0xe4/0x110 drivers/usb/usbip/vhci_hcd.c:1434
device_remove drivers/base/dd.c:616 [inline]
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372
unbind_store+0x1a1/0x1d0 drivers/base/bus.c:244
kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
insert_work+0x3d/0x330 kernel/workqueue.c:2226
__queue_work+0xcd8/0x10a0 kernel/workqueue.c:2401
queue_work_on+0x106/0x1d0 kernel/workqueue.c:2452
usb_rh_urb_dequeue drivers/usb/core/hcd.c:845 [inline]
unlink1+0x344/0x3e0 drivers/usb/core/hcd.c:1580
usb_hcd_unlink_urb+0xe6/0x1e0 drivers/usb/core/hcd.c:1617
usb_kill_urb+0x10b/0x2f0 drivers/usb/core/urb.c:716
hub_quiesce+0x211/0x330 drivers/usb/core/hub.c:1412
hub_suspend+0x904/0xad0 drivers/usb/core/hub.c:4008
usb_suspend_interface drivers/usb/core/driver.c:1323 [inline]
usb_suspend_both+0x285/0x1040 drivers/usb/core/driver.c:1446
usb_runtime_suspend+0x58/0x110 drivers/usb/core/driver.c:2000
__rpm_callback+0x2c7/0x950 drivers/base/power/runtime.c:406
rpm_callback drivers/base/power/runtime.c:460 [inline]
rpm_suspend+0x8a0/0x17b0 drivers/base/power/runtime.c:698
__pm_runtime_suspend+0x12f/0x1a0 drivers/base/power/runtime.c:1167
pm_runtime_autosuspend include/linux/pm_runtime.h:415 [inline]
usb_runtime_idle+0x76/0x90 drivers/usb/core/driver.c:2037
rpm_idle+0x5b4/0x980 drivers/base/power/runtime.c:550
pm_runtime_work+0x11e/0x1b0 drivers/base/power/runtime.c:995
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

Second to last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
insert_work+0x3d/0x330 kernel/workqueue.c:2226
__queue_work+0xcd8/0x10a0 kernel/workqueue.c:2401
queue_work_on+0x106/0x1d0 kernel/workqueue.c:2452
rh_call_control drivers/usb/core/hcd.c:706 [inline]
rh_urb_enqueue drivers/usb/core/hcd.c:817 [inline]
usb_hcd_submit_urb+0xa3b/0x1b60 drivers/usb/core/hcd.c:1538
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_port_status drivers/usb/core/hub.c:607 [inline]
hub_ext_port_status+0x114/0x810 drivers/usb/core/hub.c:624
usb_hub_port_status drivers/usb/core/hub.c:674 [inline]
hub_activate+0x740/0x1b20 drivers/usb/core/hub.c:1185
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

The buggy address belongs to the object at ffff888020bd0000
which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 5472 bytes inside of
freed 8192-byte region [ffff888020bd0000, ffff888020bd2000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20bd0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b005280 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b005280 dead000000000100 dead000000000122
head: 0000000000000000 0000000800020002 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 10, tgid 10 (kworker/0:1), ts 3790461764, 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+0x21fa/0x2270 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+0x2d5/0x350 mm/slub.c:7310
refill_sheaf mm/slub.c:2804 [inline]
__pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4675
alloc_from_pcs mm/slub.c:4773 [inline]
slab_alloc_node mm/slub.c:4905 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_noprof+0x485/0x720 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
acpi_ut_initialize_buffer+0xca/0x170 drivers/acpi/acpica/utalloc.c:-1
acpi_rs_create_pci_routing_table+0x1c0/0xd90 drivers/acpi/acpica/rscreate.c:212
acpi_rs_get_prt_method_data+0xdf/0x150 drivers/acpi/acpica/rsutils.c:456
acpi_get_irq_routing_table+0x98/0xe0 drivers/acpi/acpica/rsxface.c:137
acpi_pci_irq_find_prt_entry+0x163/0x1040 drivers/acpi/pci_irq.c:215
acpi_pci_irq_lookup+0x45/0x690 drivers/acpi/pci_irq.c:299
acpi_pci_irq_enable+0x1ee/0x7a0 drivers/acpi/pci_irq.c:414
do_pci_enable_device+0x26f/0x4a0 drivers/pci/pci.c:1998
pci_enable_device_flags+0x5ab/0x700 drivers/pci/pci.c:2089
page_owner free stack trace missing

Memory state around the buggy address:
ffff888020bd1400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888020bd1480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888020bd1500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888020bd1580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888020bd1600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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