[moderation] [kernel?] WARNING: kobject bug in goku_remove

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 48a5a7ab8d6a Merge tag 'v7.2-rc4-smb3-client-fixes' of git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17d532ea580000
kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=8fcabe1a6ee521f532d9
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
CC: [da...@kernel.org drive...@lists.linux.dev gre...@linuxfoundation.org linux-...@vger.kernel.org raf...@kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-48a5a7ab.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8ed725bee82f/vmlinux-48a5a7ab.xz
kernel image: https://storage.googleapis.com/syzbot-assets/110c09c210d5/bzImage-48a5a7ab.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8fcabe...@syzkaller.appspotmail.com

------------[ cut here ]------------
kobject: '(null)' (ffff8880574c80d8): is not initialized, yet kobject_put() is being called.
WARNING: lib/kobject.c:734 at kobject_put+0x252/0x640 lib/kobject.c:734, CPU#3: syz.9.2991/16984
Modules linked in:
CPU: 3 UID: 0 PID: 16984 Comm: syz.9.2991 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:kobject_put+0x258/0x640 lib/kobject.c:734
Code: 59 f6 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 5e 03 00 00 48 8d 3d 0e 09 84 05 48 8b 33 48 89 da <67> 48 0f b9 3a e9 0b fe ff ff e8 d9 81 59 f6 be 03 00 00 00 4c 89
RSP: 0018:ffffc90005257728 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff8880574c80d8 RCX: ffffc90024f21000
RDX: ffff8880574c80d8 RSI: 0000000000000000 RDI: ffffffff9134e3c0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880574c8114
R13: dffffc0000000000 R14: ffff8880574c8834 R15: 0000000000000000
FS: 00007fb3ff0e26c0(0000) GS:ffff8880d60de000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c31438a CR3: 000000002c6bb000 CR4: 0000000000352ef0
Call Trace:
<TASK>
put_device+0x1f/0x30 drivers/base/core.c:3880
goku_remove+0x47/0x470 drivers/usb/gadget/udc/goku_udc.c:1717
goku_probe+0x2f6/0x3c0 drivers/usb/gadget/udc/goku_udc.c:1830
local_pci_probe+0xdd/0x1b0 drivers/pci/pci-driver.c:332
pci_call_probe+0x176/0x800 drivers/pci/pci-driver.c:394
__pci_device_probe drivers/pci/pci-driver.c:455 [inline]
pci_device_probe+0x1cd/0x370 drivers/pci/pci-driver.c:489
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__driver_attach+0x21f/0x5b0 drivers/base/dd.c:1292
bus_for_each_dev+0x13e/0x1d0 drivers/base/bus.c:383
pci_add_dynid+0x2b5/0x370 drivers/pci/pci-driver.c:77
new_id_store+0x2a9/0x5b0 drivers/pci/pci-driver.c:249
drv_attr_store+0x74/0xb0 drivers/base/bus.c:125
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6ac/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb3fe19de99
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:00007fb3ff0e2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fb3fe425fa0 RCX: 00007fb3fe19de99
RDX: 000000000000000a RSI: 0000200000000200 RDI: 0000000000000003
RBP: 00007fb3fe233eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb3fe426038 R14: 00007fb3fe425fa0 R15: 00007fffe28d9848
</TASK>
----------------
Code disassembly (best guess):
0: 59 pop %rcx
1: f6 48 89 da testb $0xda,-0x77(%rax)
5: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
c: fc ff df
f: 48 c1 ea 03 shr $0x3,%rdx
13: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
17: 0f 85 5e 03 00 00 jne 0x37b
1d: 48 8d 3d 0e 09 84 05 lea 0x584090e(%rip),%rdi # 0x5840932
24: 48 8b 33 mov (%rbx),%rsi
27: 48 89 da mov %rbx,%rdx
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: e9 0b fe ff ff jmp 0xfffffe3f
34: e8 d9 81 59 f6 call 0xf6598212
39: be 03 00 00 00 mov $0x3,%esi
3e: 4c rex.WR
3f: 89 .byte 0x89


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