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BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: use-after-free in atomic64_dec_if_positive include/asm-generic/atomic-instrumented.h:1176 [inline]
BUG: KASAN: use-after-free in atomic_long_dec_if_positive include/asm-generic/atomic-long.h:515 [inline]
BUG: KASAN: use-after-free in dec_ucount+0x54/0x130 kernel/ucount.c:245
Write of size 8 at addr ffff88801748d440 by task kworker/u4:0/14480

CPU: 1 PID: 14480 Comm: kworker/u4:0 Tainted: G        W         5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:96
 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233
 __kasan_report mm/kasan/report.c:419 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:436
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic64_dec_if_positive include/asm-generic/atomic-instrumented.h:1176 [inline]
 atomic_long_dec_if_positive include/asm-generic/atomic-long.h:515 [inline]
 dec_ucount+0x54/0x130 kernel/ucount.c:245
 dec_net_namespaces net/core/net_namespace.c:394 [inline]
 cleanup_net+0x6f3/0xb10 net/core/net_namespace.c:611
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Allocated by task 8480:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 ____kasan_kmalloc mm/kasan/common.c:472 [inline]
 __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 alloc_ucounts+0x23d/0x5b0 kernel/ucount.c:169
 set_cred_ucounts+0x171/0x3a0 kernel/cred.c:684
 copy_creds+0x853/0xb20 kernel/cred.c:375
 copy_process+0x1413/0x74c0 kernel/fork.c:1992
 kernel_clone+0xe7/0xab0 kernel/fork.c:2509
 __do_compat_sys_ia32_clone+0xac/0xe0 arch/x86/kernel/sys_ia32.c:254
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 do_int80_syscall_32+0x46/0x90 arch/x86/entry/common.c:132
 entry_INT80_compat+0x71/0x76 arch/x86/entry/entry_64_compat.S:413

Freed by task 14480:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:229 [inline]
 slab_free_hook mm/slub.c:1639 [inline]
 slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1664
 slab_free mm/slub.c:3224 [inline]
 kfree+0xeb/0x670 mm/slub.c:4268
 put_ucounts kernel/ucount.c:200 [inline]
 put_ucounts+0x117/0x150 kernel/ucount.c:192
 dec_net_namespaces net/core/net_namespace.c:394 [inline]
 cleanup_net+0x6f3/0xb10 net/core/net_namespace.c:611
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff88801748d400
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 64 bytes inside of
 192-byte region [ffff88801748d400, ffff88801748d4c0)
The buggy address belongs to the page:
page:ffffea00005d2340 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1748d
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 0000000000000000 0000000200000001 ffff888011041a00
raw: 0000000000000000 0000000000100010 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 10257270451, free_ts 9546517616
 prep_new_page mm/page_alloc.c:2445 [inline]
 get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4178
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5386
 alloc_page_interleave+0x1e/0x200 mm/mempolicy.c:2147
 alloc_pages+0x238/0x2a0 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:1702 [inline]
 allocate_slab+0x32b/0x4c0 mm/slub.c:1842
 new_slab mm/slub.c:1905 [inline]
 new_slab_objects mm/slub.c:2651 [inline]
 ___slab_alloc+0x4ba/0x820 mm/slub.c:2814
 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2854
 slab_alloc_node mm/slub.c:2936 [inline]
 slab_alloc mm/slub.c:2978 [inline]
 kmem_cache_alloc_trace+0x325/0x3c0 mm/slub.c:2995
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 mon_bus_init+0x45/0x320 drivers/usb/mon/mon_main.c:287
 mon_bus_add drivers/usb/mon/mon_main.c:199 [inline]
 mon_notify+0x32c/0x490 drivers/usb/mon/mon_main.c:230
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
 blocking_notifier_call_chain kernel/notifier.c:337 [inline]
 blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:325
 usb_register_bus drivers/usb/core/hcd.c:928 [inline]
 usb_add_hcd.cold+0x3ad/0x1813 drivers/usb/core/hcd.c:2708
 vhci_hcd_probe+0x1c9/0x3a0 drivers/usb/usbip/vhci_hcd.c:1374
 platform_probe+0xfc/0x1f0 drivers/base/platform.c:1447
 really_probe+0x291/0xf60 drivers/base/dd.c:576
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1355 [inline]
 free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1406
 free_unref_page_prepare mm/page_alloc.c:3341 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3420
 __vunmap+0x783/0xb70 mm/vmalloc.c:2569
 free_work+0x58/0x70 mm/vmalloc.c:80
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff88801748d300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88801748d380: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
>ffff88801748d400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff88801748d480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88801748d500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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