==================================================================
BUG: KASAN: slab-out-of-bounds in kobject_get+0x113/0x120 lib/kobject.c:663
Read of size 1 at addr ffff88810ec0283c by task syz.0.1075/4386

CPU: 1 PID: 4386 Comm: syz.0.1075 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0x10f/0x150 mm/kasan/report.c:444
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306
 kobject_get+0x113/0x120 lib/kobject.c:663
 get_device drivers/base/core.c:3518 [inline]
 device_add+0x2f0/0xe90 drivers/base/core.c:3342
 device_create_groups_vargs drivers/base/core.c:4118 [inline]
 device_create+0x26c/0x300 drivers/base/core.c:4160
 create_function_device+0x60/0x70 drivers/usb/gadget/configfs.c:31
 create_alsa_device drivers/usb/gadget/function/f_midi.c:1262 [inline]
 f_midi_alloc_inst+0x1a8/0x380 drivers/usb/gadget/function/f_midi.c:1303
 try_get_usb_function_instance drivers/usb/gadget/functions.c:28 [inline]
 usb_get_function_instance+0xe2/0x2f0 drivers/usb/gadget/functions.c:44
 function_make+0x118/0x350 drivers/usb/gadget/configfs.c:642
 configfs_mkdir+0x50a/0x9c0 fs/configfs/dir.c:1356
 vfs_mkdir+0x38b/0x590 fs/namei.c:4073
 do_mkdirat+0x174/0x4d0 fs/namei.c:4098
 __do_sys_mkdirat fs/namei.c:4113 [inline]
 __se_sys_mkdirat fs/namei.c:4111 [inline]
 __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4111
 x64_sys_call+0x37e/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:259
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8b8e46eb19
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:00007f8b8cec6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f8b8e6f4fa0 RCX: 00007f8b8e46eb19
RDX: 0000000000000020 RSI: 0000200000000940 RDI: ffffffffffffff9c
RBP: 00007f8b8e506b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8b8e6f5038 R14: 00007f8b8e6f4fa0 R15: 00007ffc8f11de68
 </TASK>

Allocated by task 4086:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 ____kasan_kmalloc mm/kasan/common.c:512 [inline]
 __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:521
 kasan_kmalloc include/linux/kasan.h:227 [inline]
 __kmalloc_track_caller+0x13c/0x2c0 mm/slub.c:4959
 kmemdup+0x26/0x60 mm/util.c:132
 neigh_sysctl_register+0xbf/0xa90 net/core/neighbour.c:3652
 devinet_sysctl_register+0xaf/0x1e0 net/ipv4/devinet.c:2641
 inetdev_init+0x2b2/0x500 net/ipv4/devinet.c:284
 inetdev_event+0x1f4/0x1060 net/ipv4/devinet.c:1544
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:391
 call_netdevice_notifiers_info net/core/dev.c:2070 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2082 [inline]
 call_netdevice_notifiers+0x119/0x190 net/core/dev.c:2096
 register_netdevice+0x110a/0x1490 net/core/dev.c:10463
 register_vlan_dev+0x2a7/0x630 net/8021q/vlan.c:180
 vlan_newlink+0x44b/0x610 net/8021q/vlan_netlink.c:195
 __rtnl_newlink net/core/rtnetlink.c:3536 [inline]
 rtnl_newlink+0x137f/0x1900 net/core/rtnetlink.c:3584
 rtnetlink_rcv_msg+0x9fd/0xcb0 net/core/rtnetlink.c:5662
 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2520
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5680
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x86c/0xa30 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x879/0xb80 net/netlink/af_netlink.c:1923
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 __sys_sendto+0x46d/0x620 net/socket.c:2063
 __do_sys_sendto net/socket.c:2075 [inline]
 __se_sys_sendto net/socket.c:2071 [inline]
 __x64_sys_sendto+0xe5/0x100 net/socket.c:2071
 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 784:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373
 kasan_slab_free include/linux/kasan.h:193 [inline]
 slab_free_hook mm/slub.c:1728 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754
 slab_free mm/slub.c:3526 [inline]
 kfree+0xc4/0x270 mm/slub.c:4588
 neigh_sysctl_unregister+0x80/0x90 net/core/neighbour.c:3738
 devinet_sysctl_unregister net/ipv4/devinet.c:2656 [inline]
 inetdev_destroy net/ipv4/devinet.c:327 [inline]
 inetdev_event+0x7df/0x1060 net/ipv4/devinet.c:1612
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:391
 call_netdevice_notifiers_info net/core/dev.c:2070 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2082 [inline]
 call_netdevice_notifiers net/core/dev.c:2096 [inline]
 unregister_netdevice_many+0x103d/0x1a00 net/core/dev.c:11177
 default_device_exit_batch+0x35e/0x3c0 net/core/dev.c:11710
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x605/0xae0 net/core/net_namespace.c:599
 process_one_work+0x6c8/0xbb0 kernel/workqueue.c:2328
 worker_thread+0xaa0/0x1250 kernel/workqueue.c:2475
 kthread+0x3f5/0x4f0 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

The buggy address belongs to the object at ffff88810ec02000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 60 bytes to the right of
 2048-byte region [ffff88810ec02000, ffff88810ec02800)
The buggy address belongs to the page:
page:ffffea00043b0000 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88810ec00000 pfn:0x10ec00
head:ffffea00043b0000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 ffffea0004cc9a08 ffffea00046fd808 ffff888100043200
raw: ffff88810ec00000 0000000000080005 00000001ffffffff 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 0x1d28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4086, ts 262296108656, free_ts 262284685441
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2610
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2616
 get_page_from_freelist+0x2d42/0x2dd0 mm/page_alloc.c:4492
 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5829
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1937 [inline]
 new_slab+0xa0/0x4d0 mm/slub.c:2000
 ___slab_alloc+0x3ac/0x840 mm/slub.c:3033
 __slab_alloc+0x49/0x90 mm/slub.c:3120
 slab_alloc_node mm/slub.c:3211 [inline]
 slab_alloc mm/slub.c:3255 [inline]
 __kmalloc_track_caller+0x169/0x2c0 mm/slub.c:4954
 kmalloc_reserve net/core/skbuff.c:357 [inline]
 pskb_expand_head+0x123/0x1280 net/core/skbuff.c:1738
 netlink_trim+0x193/0x230 net/netlink/af_netlink.c:1299
 netlink_broadcast_filtered+0x75/0x1280 net/netlink/af_netlink.c:1516
 netlink_broadcast net/netlink/af_netlink.c:1561 [inline]
 nlmsg_multicast include/net/netlink.h:1033 [inline]
 nlmsg_notify+0xe9/0x1a0 net/netlink/af_netlink.c:2563
 rtnl_notify net/core/rtnetlink.c:762 [inline]
 rtmsg_ifinfo_send net/core/rtnetlink.c:3920 [inline]
 rtmsg_ifinfo_event net/core/rtnetlink.c:3935 [inline]
 rtnetlink_event+0x13a/0x1a0 net/core/rtnetlink.c:5713
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:391
 call_netdevice_notifiers_info+0xcb/0x110 net/core/dev.c:2070
 __netdev_upper_dev_link+0x483/0x660 net/core/dev.c:8234
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1477 [inline]
 free_pcp_prepare mm/page_alloc.c:1549 [inline]
 free_unref_page_prepare+0x5fa/0x600 mm/page_alloc.c:3540
 free_unref_page+0xae/0x540 mm/page_alloc.c:3622
 free_the_page mm/page_alloc.c:808 [inline]
 __free_pages+0x6c/0x100 mm/page_alloc.c:5905
 __free_slab+0xe5/0x1e0 mm/slub.c:2025
 free_slab mm/slub.c:2040 [inline]
 discard_slab mm/slub.c:2046 [inline]
 __unfreeze_partials+0x15a/0x190 mm/slub.c:2532
 put_cpu_partial+0xc6/0x120 mm/slub.c:2612
 __slab_free+0x1d4/0x290 mm/slub.c:3395
 do_slab_free mm/slub.c:3514 [inline]
 ___cache_free+0x104/0x120 mm/slub.c:3535
 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:157
 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xe0 mm/kasan/common.c:443
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3245 [inline]
 slab_alloc mm/slub.c:3255 [inline]
 kmem_cache_alloc+0xf7/0x260 mm/slub.c:3260
 sock_alloc_inode+0x1b/0xb0 net/socket.c:303
 alloc_inode fs/inode.c:264 [inline]
 new_inode_pseudo+0x62/0x210 fs/inode.c:1011

Memory state around the buggy address:
 ffff88810ec02700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88810ec02780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88810ec02800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                        ^
 ffff88810ec02880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88810ec02900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
------------[ cut here ]------------
general protection fault, probably for non-canonical address 0xfda3fc24200001fe: 0000 [#1] PREEMPT SMP KASAN
KASAN: maybe wild-memory-access in range [0xed20012100000ff0-0xed20012100000ff7]
CPU: 0 PID: 4386 Comm: syz.0.1075 Tainted: G    B             syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
RIP: 0010:string_nocheck lib/vsprintf.c:642 [inline]
RIP: 0010:string+0x19d/0x2a0 lib/vsprintf.c:724
Code: da 00 00 00 48 89 5d d0 4c 89 7d c0 4c 89 fb 48 ff cb 45 31 ed 4b 8d 3c 2c 48 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 75 5c 4d 01 ee 47 0f b6 3c 2c 31 ff 44 89 fe e8
RSP: 0018:ffffc90000ce7528 EFLAGS: 00010803
RAX: 1da40024200001fe RBX: fffffffffffffffe RCX: dffffc0000000000
RDX: 0000000000000002 RSI: ffffffffffffffff RDI: ed20012100000ff6
RBP: ffffc90000ce7570 R08: ffff888115fcd000 R09: 0000000000000012
R10: 0000000000000012 R11: 0000000000000002 R12: ed20012100000ff6
R13: 0000000000000000 R14: ffffc90000ce775c R15: ffffffffffffffff
FS:  00007f8b8cec66c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8b8cea4ff8 CR3: 000000012775f000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 vsnprintf+0xec5/0x1990 lib/vsprintf.c:2811
 vprintk_store+0x37f/0x13e0 kernel/printk/printk.c:2182
 vprintk_emit+0xeb/0x320 kernel/printk/printk.c:2278
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2309
 vprintk+0x7a/0x80 kernel/printk/printk_safe.c:45
 __warn_printk+0xe8/0x140 kernel/panic.c:721
 kobject_get+0x7c/0x120 lib/kobject.c:664
 get_device drivers/base/core.c:3518 [inline]
 device_add+0x2f0/0xe90 drivers/base/core.c:3342
 device_create_groups_vargs drivers/base/core.c:4118 [inline]
 device_create+0x26c/0x300 drivers/base/core.c:4160
 create_function_device+0x60/0x70 drivers/usb/gadget/configfs.c:31
 create_alsa_device drivers/usb/gadget/function/f_midi.c:1262 [inline]
 f_midi_alloc_inst+0x1a8/0x380 drivers/usb/gadget/function/f_midi.c:1303
 try_get_usb_function_instance drivers/usb/gadget/functions.c:28 [inline]
 usb_get_function_instance+0xe2/0x2f0 drivers/usb/gadget/functions.c:44
 function_make+0x118/0x350 drivers/usb/gadget/configfs.c:642
 configfs_mkdir+0x50a/0x9c0 fs/configfs/dir.c:1356
 vfs_mkdir+0x38b/0x590 fs/namei.c:4073
 do_mkdirat+0x174/0x4d0 fs/namei.c:4098
 __do_sys_mkdirat fs/namei.c:4113 [inline]
 __se_sys_mkdirat fs/namei.c:4111 [inline]
 __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4111
 x64_sys_call+0x37e/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:259
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8b8e46eb19
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:00007f8b8cec6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f8b8e6f4fa0 RCX: 00007f8b8e46eb19
RDX: 0000000000000020 RSI: 0000200000000940 RDI: ffffffffffffff9c
RBP: 00007f8b8e506b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8b8e6f5038 R14: 00007f8b8e6f4fa0 R15: 00007ffc8f11de68
 </TASK>
Modules linked in:
---[ end trace 5e3156df48196a21 ]---
RIP: 0010:string_nocheck lib/vsprintf.c:642 [inline]
RIP: 0010:string+0x19d/0x2a0 lib/vsprintf.c:724
Code: da 00 00 00 48 89 5d d0 4c 89 7d c0 4c 89 fb 48 ff cb 45 31 ed 4b 8d 3c 2c 48 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 75 5c 4d 01 ee 47 0f b6 3c 2c 31 ff 44 89 fe e8
RSP: 0018:ffffc90000ce7528 EFLAGS: 00010803
RAX: 1da40024200001fe RBX: fffffffffffffffe RCX: dffffc0000000000
RDX: 0000000000000002 RSI: ffffffffffffffff RDI: ed20012100000ff6
RBP: ffffc90000ce7570 R08: ffff888115fcd000 R09: 0000000000000012
R10: 0000000000000012 R11: 0000000000000002 R12: ed20012100000ff6
R13: 0000000000000000 R14: ffffc90000ce775c R15: ffffffffffffffff
FS:  00007f8b8cec66c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8b8cea4ff8 CR3: 000000012775f000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	da 00                	fiaddl (%rax)
   2:	00 00                	add    %al,(%rax)
   4:	48 89 5d d0          	mov    %rbx,-0x30(%rbp)
   8:	4c 89 7d c0          	mov    %r15,-0x40(%rbp)
   c:	4c 89 fb             	mov    %r15,%rbx
   f:	48 ff cb             	dec    %rbx
  12:	45 31 ed             	xor    %r13d,%r13d
  15:	4b 8d 3c 2c          	lea    (%r12,%r13,1),%rdi
  19:	48 89 f8             	mov    %rdi,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	0f b6 04 08          	movzbl (%rax,%rcx,1),%eax <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	75 5c                	jne    0x8e
  32:	4d 01 ee             	add    %r13,%r14
  35:	47 0f b6 3c 2c       	movzbl (%r12,%r13,1),%r15d
  3a:	31 ff                	xor    %edi,%edi
  3c:	44 89 fe             	mov    %r15d,%esi
  3f:	e8                   	.byte 0xe8