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

[syzbot <syzbot+306212936b13e520679d@syzkaller.appspotmail.com>]

syzbot has found a reproducer for the following issue on:

HEAD commit:    21e4543a2e2f Merge tag 'slab-for-6.14-rc5' of git://git.ke..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1753fa64580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2040405600e83619
dashboard link: https://syzkaller.appspot.com/bug?extid=306212936b13e520679d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12e1cfa0580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1a36f3b02b3c/disk-21e4543a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ef1c824f5193/vmlinux-21e4543a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/eb1e24b4d535/bzImage-21e4543a.xz

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

usb 2-1: Falling back to sysfs fallback for: ueagle-atm/eagleII.fw
------------[ cut here ]------------
WARNING: CPU: 1 PID: 6105 at fs/kernfs/dir.c:526 kernfs_get fs/kernfs/dir.c:526 [inline]
WARNING: CPU: 1 PID: 6105 at fs/kernfs/dir.c:526 kernfs_new_node+0x1d8/0x240 fs/kernfs/dir.c:703
Modules linked in:
CPU: 1 UID: 0 PID: 6105 Comm: kworker/1:8 Not tainted 6.14.0-rc5-syzkaller-00214-g21e4543a2e2f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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 08 58 c2 ff 48 89 5d 00 4c 89 f0 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d e9 19 7d a9 fe e8 f9 1a 5b 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:ffffc900032c74b8 EFLAGS: 00010293
RAX: ffffffff8266c3f7 RBX: ffff888034152d20 RCX: ffff888035b58000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8266c394 R09: 1ffff1100682a5a4
R10: dffffc0000000000 R11: ffffed100682a5a5 R12: 00000000000041ed
R13: 0000000000000000 R14: ffff88801ffe12d0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3105ffff CR3: 000000007c79e000 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:3208 [inline]
 get_device_parent+0x391/0x410 drivers/base/core.c:3259
 device_add+0x325/0xbf0 drivers/base/core.c:3589
 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+0xe55/0x1430 drivers/base/firmware_loader/main.c:941
 request_firmware_work_func+0x12a/0x280 drivers/base/firmware_loader/main.c:1194
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac0/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7ab/0x920 kernel/kthread.c:464
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>


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