syzbot
KASAN: use-after-free Read in device_create
Status:
upstream: reported C repro on 2026/07/30 16:16
Bug presence:
origin:downstream
[Documentation on labels]
Reported-by: syzbot+1573af6fa2e41a961e8e@syzkaller.appspotmail.com
First crash: 13d, last: 2h07m
▶
▼
Bug presence (3)
| Date |
Name |
Commit |
Repro |
Result |
| 2026/08/12 |
android13-5.15-lts (ToT) |
54275df9611d |
C
|
[report] KASAN: use-after-free Read in device_create
|
| 2026/08/12 |
lts (merge base) |
2047eeb38db8 |
C
|
Didn't crash |
| 2026/08/12 |
upstream (ToT) |
f5bbbfec59b4 |
C
|
Didn't crash |
Sample crash report:
==================================================================
BUG: KASAN: use-after-free in kobject_get+0x113/0x120 lib/kobject.c:663
Read of size 1 at addr ffff88810b56603c by task syz-executor204/350
CPU: 1 PID: 350 Comm: syz-executor204 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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:1329
vfs_mkdir+0x38b/0x590 fs/namei.c:4073
do_mkdirat+0x174/0x4d0 fs/namei.c:4098
__do_sys_mkdir fs/namei.c:4118 [inline]
__se_sys_mkdir fs/namei.c:4116 [inline]
__x64_sys_mkdir+0x6e/0x80 fs/namei.c:4116
x64_sys_call+0x124/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:84
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: 0033:0x7fd7dccb6679
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd4108d0d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000200000000400 RCX: 00007fd7dccb6679
RDX: 0000000000000000 RSI: 00000000000001ff RDI: 0000200000000800
RBP: 73666769666e6f63 R08: 0000000000000009 R09: 0000000000000009
R10: 0000000000000000 R11: 0000000000000246 R12: 6769666e6f632f2e
R13: 00007ffd4108d0ec R14: 00007ffd4108d100 R15: 00007ffd4108d0f0
</TASK>
Allocated by task 309:
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]
kmem_cache_alloc_trace+0x119/0x270 mm/slub.c:3274
kmalloc include/linux/slab.h:619 [inline]
kzalloc include/linux/slab.h:750 [inline]
device_create_groups_vargs drivers/base/core.c:4100 [inline]
device_create+0x13a/0x300 drivers/base/core.c:4160
android_device_create drivers/usb/gadget/configfs.c:1788 [inline]
gadgets_make+0x816/0xa70 drivers/usb/gadget/configfs.c:1885
configfs_mkdir+0x50a/0x9c0 fs/configfs/dir.c:1329
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
Freed by task 313:
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
device_create_release+0x15/0x20 drivers/base/core.c:4085
device_release+0x96/0x1c0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:713 [inline]
kobject_release lib/kobject.c:744 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x18a/0x270 lib/kobject.c:761
put_device drivers/base/core.c:3530 [inline]
device_unregister drivers/base/core.c:3656 [inline]
device_destroy+0xb4/0xf0 drivers/base/core.c:4226
android_device_destroy drivers/usb/gadget/configfs.c:1820 [inline]
gadgets_drop+0xa0/0xd0 drivers/usb/gadget/configfs.c:1901
client_drop_item fs/configfs/dir.c:933 [inline]
configfs_rmdir+0x871/0x960 fs/configfs/dir.c:1536
vfs_rmdir+0x1ae/0x450 fs/namei.c:4157
do_rmdir+0x261/0x6b0 fs/namei.c:4218
__do_sys_rmdir fs/namei.c:4237 [inline]
__se_sys_rmdir fs/namei.c:4235 [inline]
__x64_sys_rmdir+0x49/0x50 fs/namei.c:4235
x64_sys_call+0x25f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:85
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
The buggy address belongs to the object at ffff88810b566000
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 60 bytes inside of
1024-byte region [ffff88810b566000, ffff88810b566400)
The buggy address belongs to the page:
page:ffffea00042d5800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10b560
head:ffffea00042d5800 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff888100043080
raw: 0000000000000000 0000000000100010 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 300, ts 26923168864, free_ts 26876967019
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2607
prep_new_page+0x1c/0x110 mm/page_alloc.c:2613
get_page_from_freelist+0x2c3a/0x2cd0 mm/page_alloc.c:4487
__alloc_pages+0x1a2/0x460 mm/page_alloc.c:5824
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]
__alloc_skb+0x210/0x730 net/core/skbuff.c:428
alloc_skb_fclone include/linux/skbuff.h:1233 [inline]
sk_stream_alloc_skb+0x216/0xb70 net/ipv4/tcp.c:892
tcp_sendmsg_locked+0xcbb/0x3330 net/ipv4/tcp.c:1317
tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1460
inet_sendmsg+0xa5/0xc0 net/ipv4/af_inet.c:830
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
sock_write_iter+0x2a6/0x3a0 net/socket.c:1080
call_write_iter include/linux/fs.h:2212 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x831/0xfd0 fs/read_write.c:594
ksys_write+0x14a/0x260 fs/read_write.c:647
page last free stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
free_pages_prepare mm/page_alloc.c:1474 [inline]
free_pcp_prepare mm/page_alloc.c:1546 [inline]
free_unref_page_prepare+0x5fa/0x600 mm/page_alloc.c:3536
free_unref_page+0xae/0x540 mm/page_alloc.c:3618
free_the_page mm/page_alloc.c:805 [inline]
__free_pages+0x6c/0x100 mm/page_alloc.c:5900
__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
getname_flags+0xba/0x510 fs/namei.c:138
getname+0x19/0x20 fs/namei.c:217
Memory state around the buggy address:
ffff88810b565f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88810b565f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88810b566000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88810b566080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88810b566100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 350 at lib/refcount.c:25 refcount_warn_saturate+0x104/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 0 PID: 350 Comm: syz-executor204 Tainted: G B syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:refcount_warn_saturate+0x104/0x1a0 lib/refcount.c:25
Code: 04 01 48 c7 c7 40 49 63 85 e8 58 67 5a 02 0f 0b eb df e8 ef 7f 19 ff c6 05 ab f4 95 04 01 48 c7 c7 80 48 63 85 e8 3c 67 5a 02 <0f> 0b eb c3 e8 d3 7f 19 ff c6 05 90 f4 95 04 01 48 c7 c7 e0 48 63
RSP: 0018:ffffc90000ae79f8 EFLAGS: 00010246
RAX: 09d88dc8afe87300 RBX: 0000000000000002 RCX: ffff88810bd7bb40
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90000ae7a08 R08: ffffc90000ae7467 R09: 1ffff9200015ce8c
R10: dffffc0000000000 R11: fffff5200015ce8d R12: 1ffff11021ac030e
R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000000
FS: 0000555591ef43c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd4108d0ec CR3: 000000010cb9d000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__refcount_add include/linux/refcount.h:-1 [inline]
__refcount_inc include/linux/refcount.h:250 [inline]
refcount_inc include/linux/refcount.h:267 [inline]
kref_get include/linux/kref.h:45 [inline]
kobject_get+0xfb/0x120 lib/kobject.c:667
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:1329
vfs_mkdir+0x38b/0x590 fs/namei.c:4073
do_mkdirat+0x174/0x4d0 fs/namei.c:4098
__do_sys_mkdir fs/namei.c:4118 [inline]
__se_sys_mkdir fs/namei.c:4116 [inline]
__x64_sys_mkdir+0x6e/0x80 fs/namei.c:4116
x64_sys_call+0x124/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:84
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: 0033:0x7fd7dccb6679
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd4108d0d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000200000000400 RCX: 00007fd7dccb6679
RDX: 0000000000000000 RSI: 00000000000001ff RDI: 0000200000000800
RBP: 73666769666e6f63 R08: 0000000000000009 R09: 0000000000000009
R10: 0000000000000000 R11: 0000000000000246 R12: 6769666e6f632f2e
R13: 00007ffd4108d0ec R14: 00007ffd4108d100 R15: 00007ffd4108d0f0
</TASK>
---[ end trace ec83e18b2bc8ac64 ]---
------------[ cut here ]------------
refcount_t: saturated; leaking memory.
WARNING: CPU: 0 PID: 350 at lib/refcount.c:22 refcount_warn_saturate+0x158/0x1a0 lib/refcount.c:22
Modules linked in:
CPU: 0 PID: 350 Comm: syz-executor204 Tainted: G B W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:refcount_warn_saturate+0x158/0x1a0 lib/refcount.c:22
Code: 04 01 48 c7 c7 20 48 63 85 e8 04 67 5a 02 0f 0b eb 8b e8 9b 7f 19 ff c6 05 56 f4 95 04 01 48 c7 c7 20 48 63 85 e8 e8 66 5a 02 <0f> 0b e9 6c ff ff ff e8 7c 7f 19 ff c6 05 3b f4 95 04 01 48 c7 c7
RSP: 0018:ffffc90000ae78b8 EFLAGS: 00010246
RAX: 09d88dc8afe87300 RBX: 0000000000000001 RCX: ffff88810bd7bb40
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90000ae78c8 R08: ffff8881f7032f3f R09: 1ffff1103ee065e7
R10: dffffc0000000000 R11: ffffed103ee065e8 R12: 00000000c0000000
R13: ffff88810d601818 R14: 0000000000000001 R15: ffff88810b566038
FS: 0000555591ef43c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd4108d0ec CR3: 000000010cb9d000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__refcount_add include/linux/refcount.h:-1 [inline]
__refcount_inc include/linux/refcount.h:250 [inline]
refcount_inc include/linux/refcount.h:267 [inline]
kref_get include/linux/kref.h:45 [inline]
kobject_get lib/kobject.c:667 [inline]
kobject_add_internal+0xc44/0xde0 lib/kobject.c:248
kobject_add_varg lib/kobject.c:398 [inline]
kobject_add+0x165/0x230 lib/kobject.c:450
device_add+0x398/0xe90 drivers/base/core.c:3357
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:1329
vfs_mkdir+0x38b/0x590 fs/namei.c:4073
do_mkdirat+0x174/0x4d0 fs/namei.c:4098
__do_sys_mkdir fs/namei.c:4118 [inline]
__se_sys_mkdir fs/namei.c:4116 [inline]
__x64_sys_mkdir+0x6e/0x80 fs/namei.c:4116
x64_sys_call+0x124/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:84
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: 0033:0x7fd7dccb6679
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd4108d0d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000200000000400 RCX: 00007fd7dccb6679
RDX: 0000000000000000 RSI: 00000000000001ff RDI: 0000200000000800
RBP: 73666769666e6f63 R08: 0000000000000009 R09: 0000000000000009
R10: 0000000000000000 R11: 0000000000000246 R12: 6769666e6f632f2e
R13: 00007ffd4108d0ec R14: 00007ffd4108d100 R15: 00007ffd4108d0f0
</TASK>
---[ end trace ec83e18b2bc8ac65 ]---
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 350 at lib/refcount.c:28 refcount_warn_saturate+0x120/0x1a0 lib/refcount.c:28
Modules linked in:
CPU: 0 PID: 350 Comm: syz-executor204 Tainted: G B W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:refcount_warn_saturate+0x120/0x1a0 lib/refcount.c:28
Code: 04 01 48 c7 c7 80 48 63 85 e8 3c 67 5a 02 0f 0b eb c3 e8 d3 7f 19 ff c6 05 90 f4 95 04 01 48 c7 c7 e0 48 63 85 e8 20 67 5a 02 <0f> 0b eb a7 e8 b7 7f 19 ff c6 05 71 f4 95 04 01 48 c7 c7 20 48 63
RSP: 0018:ffffc90000ae7880 EFLAGS: 00010246
RAX: 09d88dc8afe87300 RBX: 0000000000000003 RCX: ffff88810bd7bb40
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90000ae7890 R08: ffff8881f7032f3f R09: 1ffff1103ee065e7
R10: dffffc0000000000 R11: ffffed103ee065e8 R12: 00000000c0000000
R13: ffff88810b56603c R14: 0000000000000003 R15: ffff88810b566038
FS: 0000555591ef43c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd4108d0ec CR3: 000000010cb9d000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__refcount_sub_and_test include/linux/refcount.h:283 [inline]
__refcount_dec_and_test include/linux/refcount.h:315 [inline]
refcount_dec_and_test include/linux/refcount.h:333 [inline]
kref_put include/linux/kref.h:64 [inline]
kobject_put+0x231/0x270 lib/kobject.c:761
kobject_add_internal+0xb52/0xde0 lib/kobject.c:266
kobject_add_varg lib/kobject.c:398 [inline]
kobject_add+0x165/0x230 lib/kobject.c:450
device_add+0x398/0xe90 drivers/base/core.c:3357
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:1329
vfs_mkdir+0x38b/0x590 fs/namei.c:4073
do_mkdirat+0x174/0x4d0 fs/namei.c:4098
__do_sys_mkdir fs/namei.c:4118 [inline]
__se_sys_mkdir fs/namei.c:4116 [inline]
__x64_sys_mkdir+0x6e/0x80 fs/namei.c:4116
x64_sys_call+0x124/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:84
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: 0033:0x7fd7dccb6679
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd4108d0d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000200000000400 RCX: 00007fd7dccb6679
RDX: 0000000000000000 RSI: 00000000000001ff RDI: 0000200000000800
RBP: 73666769666e6f63 R08: 0000000000000009 R09: 0000000000000009
R10: 0000000000000000 R11: 0000000000000246 R12: 6769666e6f632f2e
R13: 00007ffd4108d0ec R14: 00007ffd4108d100 R15: 00007ffd4108d0f0
</TASK>
---[ end trace ec83e18b2bc8ac66 ]---
kobject_add_internal failed for f_midi (error: -2 parent: o 9)
Struck through repros no longer work on HEAD.