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BUG: KASAN: use-after-free in stub_recv_cmd_submit drivers/usb/usbip/stub_rx.c:609 [inline]
BUG: KASAN: use-after-free in stub_rx_pdu drivers/usb/usbip/stub_rx.c:688 [inline]
BUG: KASAN: use-after-free in stub_rx_loop+0x2856/0x2ce0 drivers/usb/usbip/stub_rx.c:707
Read of size 4 at addr ffff888028e6c030 by task stub_rx/4374

CPU: 1 PID: 4374 Comm: stub_rx Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:420
 kasan_report+0x10b/0x140 mm/kasan/report.c:524
 stub_recv_cmd_submit drivers/usb/usbip/stub_rx.c:609 [inline]
 stub_rx_pdu drivers/usb/usbip/stub_rx.c:688 [inline]
 stub_rx_loop+0x2856/0x2ce0 drivers/usb/usbip/stub_rx.c:707
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 4374:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x18b/0x2f0 mm/slub.c:3383
 kmem_cache_zalloc include/linux/slab.h:689 [inline]
 stub_priv_alloc drivers/usb/usbip/stub_rx.c:314 [inline]
 stub_recv_cmd_submit drivers/usb/usbip/stub_rx.c:490 [inline]
 stub_rx_pdu drivers/usb/usbip/stub_rx.c:688 [inline]
 stub_rx_loop+0xa89/0x2ce0 drivers/usb/usbip/stub_rx.c:707
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 4375:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0xf7/0x2a0 mm/slub.c:3709
 stub_send_ret_submit drivers/usb/usbip/stub_tx.c:336 [inline]
 stub_tx_loop+0x19e3/0x2690 drivers/usb/usbip/stub_tx.c:440
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff888028e6c000
 which belongs to the cache stub_priv of size 64
The buggy address is located 48 bytes inside of
 64-byte region [ffff888028e6c000, ffff888028e6c040)

The buggy address belongs to the physical page:
page:ffffea0000a39b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28e6c
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888027b55140
raw: 0000000000000000 0000000080200020 00000001ffffffff 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 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 4374, tgid 4374 (stub_rx), ts 85814640734, free_ts 85782799165
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560
 prep_new_page mm/page_alloc.c:2567 [inline]
 get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358
 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658
 alloc_slab_page+0x5d/0x180 mm/slub.c:1799
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x87/0x2d0 mm/slub.c:1997
 ___slab_alloc+0xbc5/0x1240 mm/slub.c:3154
 __slab_alloc mm/slub.c:3240 [inline]
 slab_alloc_node mm/slub.c:3325 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x111/0x2f0 mm/slub.c:3383
 kmem_cache_zalloc include/linux/slab.h:689 [inline]
 stub_priv_alloc drivers/usb/usbip/stub_rx.c:314 [inline]
 stub_recv_cmd_submit drivers/usb/usbip/stub_rx.c:490 [inline]
 stub_rx_pdu drivers/usb/usbip/stub_rx.c:688 [inline]
 stub_rx_loop+0xa89/0x2ce0 drivers/usb/usbip/stub_rx.c:707
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1487 [inline]
 free_pcp_prepare mm/page_alloc.c:1537 [inline]
 free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509
 free_slab mm/slub.c:2036 [inline]
 discard_slab mm/slub.c:2042 [inline]
 __unfreeze_partials+0x188/0x1e0 mm/slub.c:2591
 put_cpu_partial+0x17c/0x250 mm/slub.c:2667
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 __kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa3/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 tomoyo_realpath_from_path+0xe2/0x5c0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x26f/0x610 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x120 security/security.c:1362
 vfs_getattr+0x26/0x3a0 fs/stat.c:158
 vfs_fstat fs/stat.c:183 [inline]
 __do_sys_newfstat fs/stat.c:447 [inline]
 __se_sys_newfstat fs/stat.c:444 [inline]
 __x64_sys_newfstat+0x13d/0x220 fs/stat.c:444
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76

Memory state around the buggy address:
 ffff888028e6bf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888028e6bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888028e6c000: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                                     ^
 ffff888028e6c080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888028e6c100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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