vhci_hcd: invalid port number 108
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BUG: KASAN: use-after-free in vhci_hub_control+0x1b88/0x1bf0 drivers/usb/usbip/vhci_hcd.c:441
Read of size 4 at addr ffff8801ce00b6bc by task syz-executor3/21872

CPU: 1 PID: 21872 Comm: syz-executor3 Not tainted 4.19.0-rc2+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x30d mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 vhci_hub_control+0x1b88/0x1bf0 drivers/usb/usbip/vhci_hcd.c:441
 rh_call_control drivers/usb/core/hcd.c:679 [inline]
 rh_urb_enqueue drivers/usb/core/hcd.c:838 [inline]
 usb_hcd_submit_urb+0x184a/0x2160 drivers/usb/core/hcd.c:1651
 usb_submit_urb+0x895/0x14d0 drivers/usb/core/urb.c:570
 usb_start_wait_urb+0x140/0x360 drivers/usb/core/message.c:57
 usb_internal_control_msg drivers/usb/core/message.c:101 [inline]
 usb_control_msg+0x332/0x4e0 drivers/usb/core/message.c:152
 proc_control+0x99b/0xef0 drivers/usb/core/devio.c:1106
 usbdev_do_ioctl+0x1eb4/0x3b30 drivers/usb/core/devio.c:2394
 usbdev_ioctl+0x25/0x30 drivers/usb/core/devio.c:2551
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
 __do_sys_ioctl fs/ioctl.c:709 [inline]
 __se_sys_ioctl fs/ioctl.c:707 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457099
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f965808ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f965808f6d4 RCX: 0000000000457099
RDX: 0000000020000000 RSI: 00000000c0185500 RDI: 0000000000000003
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004cebc0 R14: 00000000004c503e R15: 0000000000000000

Allocated by task 2538:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kmem_cache_alloc_trace+0x152/0x730 mm/slab.c:3620
 kmalloc include/linux/slab.h:513 [inline]
 kzalloc include/linux/slab.h:707 [inline]
 kernfs_iop_get_link+0x6d/0x660 fs/kernfs/symlink.c:133
 vfs_readlink+0x2a9/0x4d0 fs/namei.c:4736
 do_readlinkat+0x34d/0x400 fs/stat.c:406
 __do_sys_readlink fs/stat.c:427 [inline]
 __se_sys_readlink fs/stat.c:424 [inline]
 __x64_sys_readlink+0x78/0xb0 fs/stat.c:424
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 2538:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xd9/0x210 mm/slab.c:3813
 kfree_link+0x15/0x20 fs/libfs.c:1105
 do_delayed_call include/linux/delayed_call.h:28 [inline]
 vfs_readlink+0x204/0x4d0 fs/namei.c:4741
 do_readlinkat+0x34d/0x400 fs/stat.c:406
 __do_sys_readlink fs/stat.c:427 [inline]
 __se_sys_readlink fs/stat.c:424 [inline]
 __x64_sys_readlink+0x78/0xb0 fs/stat.c:424
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801ce00a940
 which belongs to the cache kmalloc-4096 of size 4096
The buggy address is located 3452 bytes inside of
 4096-byte region [ffff8801ce00a940, ffff8801ce00b940)
The buggy address belongs to the page:
page:ffffea0007380280 count:1 mapcount:0 mapping:ffff8801dac00dc0 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffffea0006df1888 ffffea0007658008 ffff8801dac00dc0
raw: 0000000000000000 ffff8801ce00a940 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801ce00b580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801ce00b600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801ce00b680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff8801ce00b700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801ce00b780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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