==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: slab-use-after-free in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline]
BUG: KASAN: slab-use-after-free in __refcount_add include/linux/refcount.h:184 [inline]
BUG: KASAN: slab-use-after-free in __refcount_inc include/linux/refcount.h:241 [inline]
BUG: KASAN: slab-use-after-free in refcount_inc include/linux/refcount.h:258 [inline]
BUG: KASAN: slab-use-after-free in sock_hold include/net/sock.h:774 [inline]
BUG: KASAN: slab-use-after-free in sco_sock_timeout+0x68/0x2c0 net/bluetooth/sco.c:88
Write of size 4 at addr ffff888023a47080 by task kworker/2:3/5251

CPU: 2 PID: 5251 Comm: kworker/2:3 Not tainted 6.9.0-rc2-syzkaller-00040-gb1e6ec0a0fd0 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: events sco_sock_timeout
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
 atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline]
 __refcount_add include/linux/refcount.h:184 [inline]
 __refcount_inc include/linux/refcount.h:241 [inline]
 refcount_inc include/linux/refcount.h:258 [inline]
 sock_hold include/net/sock.h:774 [inline]
 sco_sock_timeout+0x68/0x2c0 net/bluetooth/sco.c:88
 process_one_work+0x9a9/0x1ac0 kernel/workqueue.c:3254
 process_scheduled_works kernel/workqueue.c:3335 [inline]
 worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>

Allocated by task 8193:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
 kmalloc include/linux/slab.h:628 [inline]
 kmalloc_array include/linux/slab.h:664 [inline]
 netdev_create_hash+0x3c/0xc0 net/core/dev.c:11437
 netdev_init+0x70/0x230 net/core/dev.c:11453
 ops_init+0xb9/0x650 net/core/net_namespace.c:136
 setup_net+0x435/0xb40 net/core/net_namespace.c:340
 copy_net_ns+0x2f0/0x670 net/core/net_namespace.c:505
 create_new_namespaces+0x3ea/0xb10 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228
 ksys_unshare+0x419/0x970 kernel/fork.c:3322
 __do_sys_unshare kernel/fork.c:3393 [inline]
 __se_sys_unshare kernel/fork.c:3391 [inline]
 __x64_sys_unshare+0x31/0x40 kernel/fork.c:3391
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

Freed by task 1091:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:240 [inline]
 __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2106 [inline]
 slab_free mm/slub.c:4280 [inline]
 kfree+0x129/0x390 mm/slub.c:4390
 netdev_exit+0x3c/0xe0 net/core/dev.c:11558
 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:170
 cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:637
 process_one_work+0x9a9/0x1ac0 kernel/workqueue.c:3254
 process_scheduled_works kernel/workqueue.c:3335 [inline]
 worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

The buggy address belongs to the object at ffff888023a47000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 128 bytes inside of
 freed 2048-byte region [ffff888023a47000, ffff888023a47800)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23a40
head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000840 ffff888015442f00 ffffea0001141200 dead000000000002
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
head: 00fff80000000840 ffff888015442f00 ffffea0001141200 dead000000000002
head: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
head: 00fff80000000003 ffffea00008e9001 ffffea00008e9048 00000000ffffffff
head: 0000000800000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5212, tgid 5212 (syz-executor.0), ts 55543437242, free_ts 55535222653
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page mm/slub.c:2175 [inline]
 allocate_slab mm/slub.c:2338 [inline]
 new_slab+0xcc/0x3a0 mm/slub.c:2391
 ___slab_alloc+0x66d/0x1790 mm/slub.c:3525
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3610
 __slab_alloc_node mm/slub.c:3663 [inline]
 slab_alloc_node mm/slub.c:3835 [inline]
 __do_kmalloc_node mm/slub.c:3965 [inline]
 __kmalloc_node_track_caller+0x367/0x470 mm/slub.c:3986
 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:599
 pskb_expand_head+0x240/0x11f0 net/core/skbuff.c:2245
 netlink_trim+0x1ef/0x250 net/netlink/af_netlink.c:1317
 netlink_broadcast_filtered+0xc7/0xf10 net/netlink/af_netlink.c:1523
 nlmsg_multicast_filtered include/net/netlink.h:1111 [inline]
 nlmsg_multicast include/net/netlink.h:1130 [inline]
 nlmsg_notify+0x9e/0x220 net/netlink/af_netlink.c:2602
 rtnl_notify net/core/rtnetlink.c:757 [inline]
 rtmsg_ifinfo_send net/core/rtnetlink.c:4078 [inline]
 rtmsg_ifinfo_event net/core/rtnetlink.c:4094 [inline]
 rtmsg_ifinfo_event net/core/rtnetlink.c:4081 [inline]
 rtnetlink_event+0x177/0x1f0 net/core/rtnetlink.c:6646
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
 __netdev_upper_dev_link+0x43d/0x850 net/core/dev.c:7797
page last free pid 5212 tgid 5212 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmalloc_trace+0x147/0x330 mm/slub.c:3992
 kmalloc include/linux/slab.h:628 [inline]
 kzalloc include/linux/slab.h:749 [inline]
 kobject_uevent_env+0x265/0x1820 lib/kobject_uevent.c:525
 __kobject_del+0x168/0x1f0 lib/kobject.c:601
 kobject_cleanup lib/kobject.c:680 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x31c/0x5b0 lib/kobject.c:737
 net_rx_queue_update_kobjects+0x478/0x5f0 net/core/net-sysfs.c:1174
 netif_set_real_num_rx_queues+0x169/0x210 net/core/dev.c:2941
 veth_init_queues+0x151/0x190 drivers/net/veth.c:1759
 veth_newlink+0x627/0xa10 drivers/net/veth.c:1877
 rtnl_newlink_create net/core/rtnetlink.c:3494 [inline]
 __rtnl_newlink+0x1197/0x1960 net/core/rtnetlink.c:3714
 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3727
 rtnetlink_rcv_msg+0x3c7/0xe60 net/core/rtnetlink.c:6595

Memory state around the buggy address:
 ffff888023a46f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888023a47000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888023a47080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888023a47100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888023a47180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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