[syzbot] [kernfs?] WARNING in kernfs_new_node (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    1fb918967b56 Merge tag 'for-6.11-rc3-tag' of git://git.ker..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11ccfde5980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7229118d88b4a71b
dashboard link: https://syzkaller.appspot.com/bug?extid=306212936b13e520679d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/08587d4fbe1d/disk-1fb91896.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6dd5154c5ac3/vmlinux-1fb91896.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ed7b9753cd9c/bzImage-1fb91896.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+306212936b13e520679d@xxxxxxxxxxxxxxxxxxxxxxxxx

usb 5-1: Direct firmware load for ueagle-atm/eagleII.fw failed with error -2
usb 5-1: Falling back to sysfs fallback for: ueagle-atm/eagleII.fw
------------[ cut here ]------------
WARNING: CPU: 0 PID: 9066 at fs/kernfs/dir.c:526 kernfs_get fs/kernfs/dir.c:526 [inline]
WARNING: CPU: 0 PID: 9066 at fs/kernfs/dir.c:526 kernfs_new_node+0x1d8/0x240 fs/kernfs/dir.c:703
Modules linked in:
CPU: 0 UID: 0 PID: 9066 Comm: kworker/0:7 Not tainted 6.11.0-rc3-syzkaller-00066-g1fb918967b56 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: events request_firmware_work_func
RIP: 0010:kernfs_get fs/kernfs/dir.c:526 [inline]
RIP: 0010:kernfs_new_node+0x1d8/0x240 fs/kernfs/dir.c:703
Code: 74 08 48 89 ef e8 68 34 c4 ff 48 89 5d 00 4c 89 f0 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d e9 a9 a5 b9 09 e8 09 ee 5c ff 90 <0f> 0b 90 eb a0 89 e9 80 e1 07 fe c1 38 c1 0f 8c 62 fe ff ff 48 89
RSP: 0018:ffffc90004447578 EFLAGS: 00010293
RAX: ffffffff82369b67 RBX: ffff88806b7c1870 RCX: ffff888029df5a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff82369b04 R09: 1ffff1100d6f830e
R10: dffffc0000000000 R11: ffffed100d6f830f R12: 00000000000041ed
R13: 0000000000000000 R14: ffff888067d74780 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffedb7a2d4c CR3: 000000005a9c8000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 kernfs_create_dir_ns+0x43/0x120 fs/kernfs/dir.c:1061
 sysfs_create_dir_ns+0x189/0x3a0 fs/sysfs/dir.c:59
 create_dir lib/kobject.c:73 [inline]
 kobject_add_internal+0x435/0x8d0 lib/kobject.c:240
 kobject_add_varg lib/kobject.c:374 [inline]
 kobject_add+0x152/0x220 lib/kobject.c:426
 class_dir_create_and_add drivers/base/core.c:3225 [inline]
 get_device_parent+0x391/0x410 drivers/base/core.c:3276
 device_add+0x325/0xbf0 drivers/base/core.c:3606
 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:86 [inline]
 fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:162 [inline]
 firmware_fallback_sysfs+0x307/0x9e0 drivers/base/firmware_loader/fallback.c:238
 _request_firmware+0xcf5/0x12b0 drivers/base/firmware_loader/main.c:914
 request_firmware_work_func+0x12a/0x280 drivers/base/firmware_loader/main.c:1165
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>


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