==================================================================
BUG: KASAN: slab-use-after-free in find_endpoint+0x2a3/0x2c0 drivers/usb/gadget/udc/dummy_hcd.c:1618
Read of size 1 at addr ffff88807d718ce8 by task kworker/0:0/12421

CPU: 0 UID: 0 PID: 12421 Comm: kworker/0:0 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: usb_hub_wq hub_event
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 find_endpoint+0x2a3/0x2c0 drivers/usb/gadget/udc/dummy_hcd.c:1618
 dummy_timer+0x500/0x3700 drivers/usb/gadget/udc/dummy_hcd.c:1890
 __run_hrtimer kernel/time/hrtimer.c:2067 [inline]
 __hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2124
 hrtimer_run_softirq+0x1ca/0x360 kernel/time/hrtimer.c:2141
 handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0x194/0x210 kernel/softirq.c:767
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_is_held_type+0xf5/0x140 kernel/locking/lockdep.c:5987
Code: ff ff ff ff 65 0f c1 15 f1 e6 bc 08 83 fa 01 8b 44 24 04 75 2d 9c 5a 80 e6 02 75 47 41 f7 c5 00 02 00 00 74 01 fb 48 83 c4 08 <5b> 5d 41 5c 41 5d 41 5e 41 5f e9 4c 46 03 00 e9 47 46 03 00 31 c0
RSP: 0018:ffffc900038beaf0 EFLAGS: 00000296
RAX: 0000000000000001 RBX: ffffffff8edec060 RCX: 0000000000000001
RDX: 0000000000000046 RSI: ffffffff8e3c4c52 RDI: ffffffff8c620e80
RBP: ffff888029e90000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 00000000ffffffff
R13: 0000000000000246 R14: ffff888029e90ca0 R15: 0000000000000006
 kernfs_root+0x20e/0x2a0 fs/kernfs/kernfs-internal.h:77
 kernfs_root_is_locked fs/kernfs/kernfs-internal.h:110 [inline]
 kernfs_rcu_name fs/kernfs/kernfs-internal.h:120 [inline]
 kernfs_add_one+0x623/0xaa0 fs/kernfs/dir.c:842
 kernfs_create_dir_ns+0x157/0x2b0 fs/kernfs/dir.c:1130
 sysfs_create_dir_ns+0x13a/0x2b0 fs/sysfs/dir.c:59
 create_dir lib/kobject.c:73 [inline]
 kobject_add_internal+0x2c8/0x930 lib/kobject.c:240
 kobject_add_varg lib/kobject.c:374 [inline]
 kobject_add+0x16a/0x1e0 lib/kobject.c:426
 device_add+0x294/0x1970 drivers/base/core.c:3699
 usb_serial_probe.cold+0x257e/0x29f8 drivers/usb/serial/usb-serial.c:1147
 usb_probe_interface+0x386/0x9b0 drivers/usb/core/driver.c:399
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3776
 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3776
 usb_new_device.part.0+0xcc2/0x1686 drivers/usb/core/hub.c:2708
 usb_new_device include/linux/workqueue.h:715 [inline]
 hub_port_connect drivers/usb/core/hub.c:5580 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
 port_event drivers/usb/core/hub.c:5884 [inline]
 hub_event.cold+0x1e3/0xe90 drivers/usb/core/hub.c:5966
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
 process_scheduled_works kernel/workqueue.c:3479 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 12128:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5414 [inline]
 __kmalloc_flags_noprof+0x370/0x8e0 mm/slub.c:5602
 _kmalloc_flags_noprof mm/slab.h:55 [inline]
 alloc_slab_obj_exts+0x6a/0x170 mm/slub.c:2186
 account_slab mm/slub.c:3419 [inline]
 allocate_slab mm/slub.c:3498 [inline]
 new_slab+0x4ac/0x6e0 mm/slub.c:3513
 refill_objects+0xe3/0x410 mm/slub.c:7410
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 kmem_cache_alloc_noprof+0x4c4/0x6a0 mm/slub.c:5010
 sigqueue_alloc kernel/signal.c:437 [inline]
 __send_signal_locked+0x155/0x12d0 kernel/signal.c:1067
 send_signal_locked+0x15e/0xa00 kernel/signal.c:1207
 do_send_sig_info+0xa3/0x130 kernel/signal.c:1260
 send_sigio_to_task+0x491/0x710 fs/fcntl.c:902
 send_sigio+0x29e/0x4a0 fs/fcntl.c:929
 dnotify_handle_event+0x15e/0x2b0 fs/notify/dnotify/dnotify.c:113
 fsnotify_handle_inode_event.isra.0+0x1e3/0x480 fs/notify/fsnotify.c:275
 fsnotify_handle_event fs/notify/fsnotify.c:304 [inline]
 send_to_group fs/notify/fsnotify.c:378 [inline]
 fsnotify+0x1a8e/0x3240 fs/notify/fsnotify.c:597
 __fsnotify_parent+0x6c3/0xd00 fs/notify/fsnotify.c:241
 fsnotify_parent include/linux/fsnotify.h:96 [inline]
 fsnotify_path include/linux/fsnotify.h:113 [inline]
 fsnotify_file include/linux/fsnotify.h:127 [inline]
 fsnotify_file include/linux/fsnotify.h:116 [inline]
 fsnotify_access include/linux/fsnotify.h:429 [inline]
 __kernel_read+0x5b2/0xad0 fs/read_write.c:536
 integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
 ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
 ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
 ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
 process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
 ima_file_check+0xc3/0x110 security/integrity/ima/ima_main.c:685
 security_file_post_open+0xc4/0x210 security/security.c:2755
 do_open fs/namei.c:4839 [inline]
 path_openat+0x5cd/0x2440 fs/namei.c:5000
 do_file_open+0x20e/0x430 fs/namei.c:5029
 do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_sys_open fs/open.c:1431 [inline]
 __se_sys_open fs/open.c:1427 [inline]
 __x64_sys_open+0xfe/0x1d0 fs/open.c:1427
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5596:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6499 [inline]
 kfree+0x22b/0x6d0 mm/slub.c:6792
 free_slab_obj_exts mm/slub.c:2274 [inline]
 unaccount_slab mm/slub.c:3434 [inline]
 __free_slab+0x13d/0x220 mm/slub.c:3526
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 kmem_cache_alloc_noprof+0x269/0x6a0 mm/slub.c:5010
 alloc_filename fs/namei.c:147 [inline]
 do_getname+0x35/0x390 fs/namei.c:187
 getname_flags fs/namei.c:230 [inline]
 class_filename_flags_constructor include/linux/fs.h:2586 [inline]
 user_path_at+0x26/0x60 fs/namei.c:3640
 ksys_umount fs/namespace.c:2067 [inline]
 __do_sys_umount fs/namespace.c:2075 [inline]
 __se_sys_umount fs/namespace.c:2073 [inline]
 __x64_sys_umount+0x10a/0x1a0 fs/namespace.c:2073
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807d718c00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 232 bytes inside of
 freed 512-byte region [ffff88807d718c00, ffff88807d718e00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d718
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801c02ec80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801c02ec80 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5601, tgid 5601 (syz-executor), ts 64214005639
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3347 [inline]
 allocate_slab mm/slub.c:3462 [inline]
 new_slab+0xa9/0x6e0 mm/slub.c:3513
 refill_objects+0xe3/0x410 mm/slub.c:7410
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 __kmalloc_cache_noprof+0x4f4/0x6d0 mm/slub.c:5559
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 mca_alloc net/ipv6/mcast.c:871 [inline]
 __ipv6_dev_mc_inc+0x2f1/0xbd0 net/ipv6/mcast.c:962
 ipv6_add_dev+0xb87/0x1520 net/ipv6/addrconf.c:475
 addrconf_notify+0x5db/0x1ba0 net/ipv6/addrconf.c:3686
 notifier_call_chain+0x99/0x3f0 kernel/notifier.c:85
 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2275
 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline]
 call_netdevice_notifiers net/core/dev.c:2327 [inline]
 register_netdevice+0x1998/0x25a0 net/core/dev.c:11541
 register_netdev+0x34/0x50 net/core/dev.c:11620
 vti6_init_net+0x2ff/0x480 net/ipv6/ip6_vti.c:1173
 ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137
page last free pid 4976 tgid 4976 ts 24204811593 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 __kmalloc_cache_noprof+0x278/0x6d0 mm/slub.c:5559
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 inode_doinit_use_xattr+0x54/0x330 security/selinux/hooks.c:1379
 inode_doinit_with_dentry+0x10fc/0x1340 security/selinux/hooks.c:1574
 selinux_d_instantiate+0x26/0x40 security/selinux/hooks.c:6685
 security_d_instantiate+0x14c/0x1b0 security/security.c:3703
 d_splice_alias_ops+0xd7/0x15b0 fs/dcache.c:3249
 kernfs_iop_lookup+0x23f/0x2d0 fs/kernfs/dir.c:1288
 lookup_open+0xa79/0x1990 fs/namei.c:4528
 open_last_lookups fs/namei.c:4767 [inline]
 path_openat+0xa2c/0x2440 fs/namei.c:4997
 do_file_open+0x20e/0x430 fs/namei.c:5029
 do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_sys_openat fs/open.c:1439 [inline]
 __se_sys_openat fs/open.c:1434 [inline]
 __x64_sys_openat+0x12d/0x210 fs/open.c:1434

Memory state around the buggy address:
 ffff88807d718b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807d718c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807d718c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff88807d718d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d718d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess), 3 bytes skipped:
   0:	ff 65 0f             	jmp    *0xf(%rbp)
   3:	c1 15 f1 e6 bc 08 83 	rcll   $0x83,0x8bce6f1(%rip)        # 0x8bce6fb
   a:	fa                   	cli
   b:	01 8b 44 24 04 75    	add    %ecx,0x75042444(%rbx)
  11:	2d 9c 5a 80 e6       	sub    $0xe6805a9c,%eax
  16:	02 75 47             	add    0x47(%rbp),%dh
  19:	41 f7 c5 00 02 00 00 	test   $0x200,%r13d
  20:	74 01                	je     0x23
  22:	fb                   	sti
  23:	48 83 c4 08          	add    $0x8,%rsp
* 27:	5b                   	pop    %rbx <-- trapping instruction
  28:	5d                   	pop    %rbp
  29:	41 5c                	pop    %r12
  2b:	41 5d                	pop    %r13
  2d:	41 5e                	pop    %r14
  2f:	41 5f                	pop    %r15
  31:	e9 4c 46 03 00       	jmp    0x34682
  36:	e9 47 46 03 00       	jmp    0x34682
  3b:	31 c0                	xor    %eax,%eax