syzbot


WARNING in kernfs_get

Status: upstream: reported on 2025/06/28 04:30
Reported-by: syzbot+9fff6b476ec89fe103eb@syzkaller.appspotmail.com
First crash: 20d, last: 3d17h
Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in kernfs_get (5) usb kernfs -1 syz inconclusive 414 2d00h 435d 0/29 upstream: reported syz repro on 2024/05/08 11:07
linux-4.19 WARNING in kernfs_get -1 C done 14 2135d 2275d 1/1 fixed on 2019/12/05 23:59
upstream WARNING in kernfs_get (2) kernfs -1 2 1755d 1773d 0/29 auto-closed as invalid on 2021/01/25 03:55
linux-4.14 WARNING in kernfs_get -1 C done 17 2159d 2279d 1/1 fixed on 2019/12/07 19:24
upstream WARNING in kernfs_get (4) kernfs -1 syz error 3 891d 894d 0/29 auto-obsoleted due to no activity on 2023/06/07 19:32
upstream WARNING in kernfs_get -1 C done 316 2174d 2502d 13/29 fixed on 2019/11/20 22:01
upstream WARNING in kernfs_get (3) kernfs -1 3 1319d 1324d 0/29 auto-closed as invalid on 2022/02/04 06:25
android-414 WARNING in kernfs_get -1 syz 69 2138d 2290d 0/1 public: reported syz repro on 2019/04/10 15:44

Sample crash report:
usb 4-1: Direct firmware load for ueagle-atm/eagleII.fw failed with error -2
usb 4-1: Falling back to sysfs fallback for: ueagle-atm/eagleII.fw
------------[ cut here ]------------
WARNING: CPU: 0 PID: 788 at fs/kernfs/dir.c:526 kernfs_get+0x6c/0x90 fs/kernfs/dir.c:526
Modules linked in:
CPU: 0 PID: 788 Comm: kworker/0:2 Not tainted 6.6.97-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events request_firmware_work_func
RIP: 0010:kernfs_get+0x6c/0x90 fs/kernfs/dir.c:526
Code: 72 ff 85 ed 74 1f e8 63 55 72 ff 48 89 df be 04 00 00 00 e8 16 06 cb ff f0 ff 03 eb 05 e8 4c 55 72 ff 5b 5d c3 e8 44 55 72 ff <0f> 0b eb dd 89 d9 80 e1 07 80 c1 03 38 c1 7c bd 48 89 df e8 ec 03
RSP: 0000:ffffc90003d87740 EFLAGS: 00010293
RAX: ffffffff8213412c RBX: ffff88807d7800f8 RCX: ffff8880212d8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88807d7800fb R09: 1ffff1100faf001f
R10: dffffc0000000000 R11: ffffed100faf0020 R12: ffff88802fc6fba8
R13: 1ffff11005f8df76 R14: ffff88802fc6fbb0 R15: ffff88802fc6fb98
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c327196 CR3: 0000000079d91000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 sysfs_get include/linux/sysfs.h:651 [inline]
 create_dir lib/kobject.c:89 [inline]
 kobject_add_internal+0x74b/0xc70 lib/kobject.c:240
 kobject_add_varg lib/kobject.c:374 [inline]
 kobject_add+0x156/0x220 lib/kobject.c:426
 class_dir_create_and_add drivers/base/core.c:3226 [inline]
 get_device_parent+0x316/0x390 drivers/base/core.c:3277
 device_add+0x2e1/0xc20 drivers/base/core.c:3607
 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:82 [inline]
 fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:158 [inline]
 firmware_fallback_sysfs+0x2e9/0x940 drivers/base/firmware_loader/fallback.c:234
 _request_firmware+0xed9/0x1510 drivers/base/firmware_loader/main.c:936
 request_firmware_work_func+0xb0/0x1b0 drivers/base/firmware_loader/main.c:1189
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/14 12:10 linux-6.6.y 59a2de10b81a d8fc7335 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in kernfs_get
2025/07/10 10:45 linux-6.6.y a5df3a702b2c 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in kernfs_get
2025/07/10 10:43 linux-6.6.y a5df3a702b2c 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in kernfs_get
2025/06/28 04:29 linux-6.6.y 3f5b4c104b7d fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in kernfs_get
* Struck through repros no longer work on HEAD.