==================================================================
BUG: KASAN: slab-use-after-free in gphonet_set_gadget drivers/usb/gadget/function/f_phonet.c:720 [inline]
BUG: KASAN: slab-use-after-free in pn_bind+0x106/0xb20 drivers/usb/gadget/function/f_phonet.c:510
Write of size 8 at addr ffff888036100900 by task syz.4.616/9462

CPU: 0 UID: 0 PID: 9462 Comm: syz.4.616 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
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
 gphonet_set_gadget drivers/usb/gadget/function/f_phonet.c:720 [inline]
 pn_bind+0x106/0xb20 drivers/usb/gadget/function/f_phonet.c:510
 usb_add_function+0x290/0x930 drivers/usb/gadget/composite.c:333
 configfs_composite_bind+0xde0/0x1410 drivers/usb/gadget/configfs.c:1802
 gadget_bind_driver+0x2ca/0x9e0 drivers/usb/gadget/udc/core.c:1662
 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
 __driver_attach+0x339/0x600 drivers/base/dd.c:1292
 bus_for_each_dev+0x23e/0x2c0 drivers/base/bus.c:383
 bus_add_driver+0x348/0x670 drivers/base/bus.c:763
 driver_register+0x23a/0x320 drivers/base/driver.c:174
 usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1752
 gadget_dev_desc_UDC_store+0x1c9/0x2f0 drivers/usb/gadget/configfs.c:300
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x33a/0x430 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x61e/0xbb0 fs/read_write.c:687
 ksys_write+0x156/0x270 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
RIP: 0033:0x7f1c2765de99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1c258b6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f1c278e5fa0 RCX: 00007f1c2765de99
RDX: 000000000000000c RSI: 0000200000000240 RDI: 0000000000000005
RBP: 00007f1c276f3eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1c278e6038 R14: 00007f1c278e5fa0 R15: 00007ffff7dbdbf8
 </TASK>

Allocated by task 8278:
 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]
 __kvmalloc_node_noprof+0x5be/0x8a0 mm/slub.c:6905
 alloc_netdev_mqs+0xa9/0x12c0 net/core/dev.c:12054
 rtnl_create_link+0x321/0xd70 net/core/rtnetlink.c:3721
 rtnl_newlink_create+0x25f/0xb00 net/core/rtnetlink.c:3903
 __rtnl_newlink net/core/rtnetlink.c:4044 [inline]
 rtnl_newlink+0x167f/0x1bd0 net/core/rtnetlink.c:4159
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x41e/0x5d0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 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

Freed by task 6011:
 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+0x1c5/0x6c0 mm/slub.c:6692
 device_release+0xc4/0x1f0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x222/0x550 lib/kobject.c:737
 netdev_run_todo+0xf56/0x10d0 net/core/dev.c:11755
 default_device_exit_batch+0x966/0x9e0 net/core/dev.c:13100
 ops_exit_list net/core/net_namespace.c:205 [inline]
 ops_undo_list+0x4b4/0x8d0 net/core/net_namespace.c:252
 cleanup_net+0x575/0x810 net/core/net_namespace.c:702
 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 ffff888036100000
 which belongs to the cache kmalloc-cg-8k of size 8192
The buggy address is located 2304 bytes inside of
 freed 8192-byte region [ffff888036100000, ffff888036102000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x36100
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888036102011
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88813ffbb640 dead000000000100 dead000000000122
raw: 0000000000000000 0000400000020002 00000000f5000000 ffff888036102011
head: 0080000000000040 ffff88813ffbb640 dead000000000100 dead000000000122
head: 0000000000000000 0000400000020002 00000000f5000000 ffff888036102011
head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 0xd60c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6354, tgid 6354 (syz-executor), ts 206261291286, free_ts 205587364869
 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+0x262a/0x26a0 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+0x2d8/0x350 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x330/0x690 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]
 __kvmalloc_node_noprof+0x703/0x8a0 mm/slub.c:6905
 alloc_netdev_mqs+0xa9/0x12c0 net/core/dev.c:12054
 rtnl_create_link+0x321/0xd70 net/core/rtnetlink.c:3721
 rtnl_newlink_create+0x25f/0xb00 net/core/rtnetlink.c:3903
 __rtnl_newlink net/core/rtnetlink.c:4044 [inline]
 rtnl_newlink+0x167f/0x1bd0 net/core/rtnetlink.c:4159
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
page last free pid 6354 tgid 6354 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0x10e7/0x11c0 mm/page_alloc.c:2950
 __slab_free+0x252/0x2a0 mm/slub.c:5741
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4584 [inline]
 slab_alloc_node mm/slub.c:4917 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_node_track_caller_noprof+0x519/0x7c0 mm/slub.c:5471
 kvasprintf+0xeb/0x1a0 lib/kasprintf.c:25
 kasprintf+0xe2/0x140 lib/kasprintf.c:59
 wq_init_lockdep kernel/workqueue.c:4935 [inline]
 alloc_workqueue_va kernel/workqueue.c:5948 [inline]
 alloc_workqueue_noprof+0x12e/0x210 kernel/workqueue.c:5962
 wg_newlink+0x2a8/0x670 drivers/net/wireguard/device.c:346
 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3913
 __rtnl_newlink net/core/rtnetlink.c:4044 [inline]
 rtnl_newlink+0x167f/0x1bd0 net/core/rtnetlink.c:4159
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900

Memory state around the buggy address:
 ffff888036100800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888036100880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888036100900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888036100980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888036100a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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