==================================================================
BUG: KASAN: slab-use-after-free in list_empty include/linux/list.h:373 [inline]
BUG: KASAN: slab-use-after-free in driver_deferred_probe_del+0x78/0x240 drivers/base/dd.c:148
Read of size 8 at addr ffff8881189c04a8 by task syz.2.19/400

CPU: 0 UID: 0 PID: 400 Comm: syz.2.19 Not tainted syzkaller #0 f10dc98c92500eb86b2a5bf5b389293121b4eb86
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 print_address_description+0x71/0x210 mm/kasan/report.c:377
 print_report+0x4a/0x70 mm/kasan/report.c:481
 kasan_report+0x162/0x1a0 mm/kasan/report.c:594
 __asan_report_load8_noabort+0x18/0x20 mm/kasan/report_generic.c:381
 list_empty include/linux/list.h:373 [inline]
 driver_deferred_probe_del+0x78/0x240 drivers/base/dd.c:148
 device_del+0x593/0xcf0 drivers/base/core.c:3883
 usb_del_gadget+0x18f/0x200 drivers/usb/gadget/udc/core.c:1550
 usb_del_gadget_udc+0x19/0x30 drivers/usb/gadget/udc/core.c:1566
 dummy_udc_remove+0x5c/0x70 drivers/usb/gadget/udc/dummy_hcd.c:1123
 platform_remove+0x81/0xb0 drivers/base/platform.c:1424
 device_remove drivers/base/dd.c:567 [inline]
 __device_release_driver drivers/base/dd.c:1272 [inline]
 device_release_driver_internal+0x4ad/0x830 drivers/base/dd.c:1295
 device_driver_detach+0x3f/0x50 drivers/base/dd.c:1331
 unbind_store+0x1ab/0x1f0 drivers/base/bus.c:244
 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125
 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x762/0xfd0 fs/read_write.c:684
 ksys_write+0x145/0x260 fs/read_write.c:737
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x7f/0x90 fs/read_write.c:746
 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f843039de99
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:00007ffeaf227308 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8430625fa0 RCX: 00007f843039de99
RDX: 000000000000000b RSI: 0000200000000400 RDI: 0000000000000003
RBP: 00007f8430433eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8430625fac R14: 00007f8430625fa0 R15: 00007f8430625fa0
 </TASK>

Allocated by task 401:
 kasan_save_stack mm/kasan/common.c:49 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:70
 kasan_save_alloc_info+0x3a/0x50 mm/kasan/generic.c:565
 poison_kmalloc_redzone mm/kasan/common.c:379 [inline]
 __kasan_kmalloc+0x96/0xb0 mm/kasan/common.c:396
 kasan_kmalloc include/linux/kasan.h:261 [inline]
 __kmalloc_cache_noprof+0x23c/0x470 mm/slub.c:4426
 kmalloc_noprof include/linux/slab.h:881 [inline]
 kzalloc_noprof include/linux/slab.h:1017 [inline]
 device_private_init drivers/base/core.c:3537 [inline]
 device_add+0xc1/0xbf0 drivers/base/core.c:3588
 usb_add_gadget+0x3e9/0x6e0 drivers/usb/gadget/udc/core.c:1427
 usb_add_gadget_udc_release drivers/usb/gadget/udc/core.c:1477 [inline]
 usb_add_gadget_udc+0x11e/0x160 drivers/usb/gadget/udc/core.c:1524
 dummy_udc_probe+0x6ea/0x7f0 drivers/usb/gadget/udc/dummy_hcd.c:1102
 platform_probe+0x17a/0x200 drivers/base/platform.c:1404
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2e1/0x8b0 drivers/base/dd.c:657
 __driver_probe_device+0x193/0x280 drivers/base/dd.c:799
 device_driver_attach+0xdb/0x1f0 drivers/base/dd.c:1126
 bind_store+0x1dc/0x230 drivers/base/bus.c:267
 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125
 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x762/0xfd0 fs/read_write.c:684
 ksys_write+0x145/0x260 fs/read_write.c:737
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x7f/0x90 fs/read_write.c:746
 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Freed by task 400:
 kasan_save_stack mm/kasan/common.c:49 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:70
 kasan_save_free_info+0x44/0x50 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:249 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2445 [inline]
 slab_free mm/slub.c:4714 [inline]
 kfree+0x158/0x440 mm/slub.c:4875
 device_release+0xb6/0x1e0 drivers/base/core.c:2572
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1a7/0x2a0 lib/kobject.c:737
 put_device+0x23/0x40 drivers/base/core.c:3800
 klist_devices_put+0x3c/0x60 drivers/base/bus.c:817
 klist_put lib/klist.c:221 [inline]
 klist_del+0xf5/0x120 lib/klist.c:230
 bus_remove_device+0x33f/0x370 drivers/base/bus.c:572
 device_del+0x583/0xcf0 drivers/base/core.c:3881
 usb_del_gadget+0x18f/0x200 drivers/usb/gadget/udc/core.c:1550
 usb_del_gadget_udc+0x19/0x30 drivers/usb/gadget/udc/core.c:1566
 dummy_udc_remove+0x5c/0x70 drivers/usb/gadget/udc/dummy_hcd.c:1123
 platform_remove+0x81/0xb0 drivers/base/platform.c:1424
 device_remove drivers/base/dd.c:567 [inline]
 __device_release_driver drivers/base/dd.c:1272 [inline]
 device_release_driver_internal+0x4ad/0x830 drivers/base/dd.c:1295
 device_driver_detach+0x3f/0x50 drivers/base/dd.c:1331
 unbind_store+0x1ab/0x1f0 drivers/base/bus.c:244
 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125
 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x762/0xfd0 fs/read_write.c:684
 ksys_write+0x145/0x260 fs/read_write.c:737
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x7f/0x90 fs/read_write.c:746
 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

The buggy address belongs to the object at ffff8881189c0400
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 168 bytes inside of
 freed 256-byte region [ffff8881189c0400, ffff8881189c0500)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1189c0
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x4000000000000040(head|zone=1)
page_type: f5(slab)
raw: 4000000000000040 ffff888100041b40 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000
head: 4000000000000040 ffff888100041b40 dead000000000122 0000000000000000
head: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000
head: 4000000000000001 ffffea0004627001 ffffffffffffffff 0000000000000000
head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 401, tgid 401 (syz.3.20), ts 27476561242, free_ts 27456625257
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook+0x37d/0x3b0 mm/page_alloc.c:1863
 prep_new_page+0x2d/0x180 mm/page_alloc.c:1871
 get_page_from_freelist+0x4aea/0x4ba0 mm/page_alloc.c:3948
 __alloc_pages_noprof+0x35a/0x7e0 mm/page_alloc.c:5315
 alloc_slab_page+0x6b/0x1e0 mm/slub.c:-1
 allocate_slab+0x69/0x430 mm/slub.c:2687
 new_slab mm/slub.c:2741 [inline]
 ___slab_alloc+0x591/0x8c0 mm/slub.c:3934
 __slab_alloc mm/slub.c:4025 [inline]
 __slab_alloc_node mm/slub.c:4078 [inline]
 slab_alloc_node mm/slub.c:4239 [inline]
 __kmalloc_cache_noprof+0x2cd/0x470 mm/slub.c:4421
 kmalloc_noprof include/linux/slab.h:881 [inline]
 inode_doinit_use_xattr+0x6a/0x550 security/selinux/hooks.c:1375
 inode_doinit_with_dentry+0x9b1/0xde0 security/selinux/hooks.c:1569
 selinux_d_instantiate+0x2b/0x40 security/selinux/hooks.c:6361
 security_d_instantiate+0xb8/0xf0 security/security.c:4068
 d_splice_alias+0x71/0x3a0 fs/dcache.c:2949
 kernfs_iop_lookup+0x2c6/0x320 fs/kernfs/dir.c:1233
 lookup_open fs/namei.c:3581 [inline]
 open_last_lookups fs/namei.c:3702 [inline]
 path_openat+0x1127/0x35a0 fs/namei.c:3938
 do_filp_open+0x1f2/0x440 fs/namei.c:3968
page last free pid 385 tgid 385 stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1390 [inline]
 free_unref_page+0xbb8/0xf70 mm/page_alloc.c:2876
 __free_pages+0x6b/0x3b0 mm/page_alloc.c:5402
 __free_slab+0xb2/0x110 mm/slub.c:2758
 free_slab+0x18/0xe0 mm/slub.c:2781
 discard_slab mm/slub.c:2787 [inline]
 __put_partials+0x115/0x150 mm/slub.c:3256
 put_cpu_partial+0x91/0xc0 mm/slub.c:3331
 __slab_free+0x1cf/0x2a0 mm/slub.c:4584
 do_slab_free mm/slub.c:4666 [inline]
 ___cache_free+0xc9/0xe0 mm/slub.c:4781
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0xb5/0x130 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x180 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x28/0x90 mm/kasan/common.c:331
 kasan_slab_alloc include/linux/kasan.h:251 [inline]
 slab_post_alloc_hook mm/slub.c:4202 [inline]
 slab_alloc_node mm/slub.c:4251 [inline]
 kmem_cache_alloc_noprof+0x1bf/0x410 mm/slub.c:4260
 getname_flags+0xcc/0x6b0 fs/namei.c:139
 getname fs/namei.c:225 [inline]
 __do_sys_mkdirat fs/namei.c:4303 [inline]
 __se_sys_mkdirat fs/namei.c:4301 [inline]
 __x64_sys_mkdirat+0x7e/0xa0 fs/namei.c:4301
 x64_sys_call+0x2ba8/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:259
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78

Memory state around the buggy address:
 ffff8881189c0380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881189c0400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881189c0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff8881189c0500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881189c0580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 400 at lib/refcount.c:28 refcount_warn_saturate+0x119/0x1c0 lib/refcount.c:28
Modules linked in:
CPU: 0 UID: 0 PID: 400 Comm: syz.2.19 Tainted: G    B              syzkaller #0 f10dc98c92500eb86b2a5bf5b389293121b4eb86
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:refcount_warn_saturate+0x119/0x1c0 lib/refcount.c:28
Code: 05 01 48 c7 c7 00 eb 51 86 e8 43 8f 55 fe 0f 0b eb da e8 ea b8 d8 fe c6 05 47 87 36 05 01 48 c7 c7 60 eb 51 86 e8 27 8f 55 fe <0f> 0b eb be e8 ce b8 d8 fe c6 05 28 87 36 05 01 48 c7 c7 a0 ea 51
RSP: 0018:ffffc90001aafa48 EFLAGS: 00010246

RAX: 892f8e45c04f1900 RBX: 0000000000000003 RCX: ffff888115731300
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc90001aafa58 R08: ffffc90001aaf727 R09: 1ffff92000355ee4
R10: dffffc0000000000 R11: fffff52000355ee5 R12: 0000000000000000
R13: ffff888102798d34 R14: ffff888102798d30 R15: ffff888102798d30
FS:  0000555595435500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc6cefba70 CR3: 000000011896c000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 __refcount_sub_and_test include/linux/refcount.h:400 [inline]
 __refcount_dec_and_test include/linux/refcount.h:432 [inline]
 refcount_dec_and_test include/linux/refcount.h:450 [inline]
 kref_put include/linux/kref.h:64 [inline]
 kobject_put+0x25a/0x2a0 lib/kobject.c:737
 put_device+0x23/0x40 drivers/base/core.c:3800
 usb_put_gadget include/linux/usb/gadget.h:512 [inline]
 usb_del_gadget_udc+0x25/0x30 drivers/usb/gadget/udc/core.c:1567
 dummy_udc_remove+0x5c/0x70 drivers/usb/gadget/udc/dummy_hcd.c:1123
 platform_remove+0x81/0xb0 drivers/base/platform.c:1424
 device_remove drivers/base/dd.c:567 [inline]
 __device_release_driver drivers/base/dd.c:1272 [inline]
 device_release_driver_internal+0x4ad/0x830 drivers/base/dd.c:1295
 device_driver_detach+0x3f/0x50 drivers/base/dd.c:1331
 unbind_store+0x1ab/0x1f0 drivers/base/bus.c:244
 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125
 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x762/0xfd0 fs/read_write.c:684
 ksys_write+0x145/0x260 fs/read_write.c:737
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x7f/0x90 fs/read_write.c:746
 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f843039de99
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:00007ffeaf227308 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8430625fa0 RCX: 00007f843039de99
RDX: 000000000000000b RSI: 0000200000000400 RDI: 0000000000000003
RBP: 00007f8430433eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8430625fac R14: 00007f8430625fa0 R15: 00007f8430625fa0
 </TASK>
---[ end trace 0000000000000000 ]---