[syzbot] [fs?] general protection fault in start_dirop

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 62cc90241548 Merge tag 'mm-hotfixes-stable-2026-07-27-14-1..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13377fde580000
kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=1e3d934ee3cff1ac188b
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=111916b9580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10aa0aea580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-62cc9024.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b10a9ae7e3d1/vmlinux-62cc9024.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b89124d39495/bzImage-62cc9024.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1e3d93...@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000028: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000140-0x0000000000000147]
CPU: 3 UID: 0 PID: 6582 Comm: syz.0.150 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:kasan_byte_accessible+0x15/0x30 mm/kasan/generic.c:210
Code: 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 b8 00 00 00 00 00 fc ff df 48 c1 ef 03 48 01 c7 <0f> b6 07 3c 07 0f 96 c0 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
RSP: 0018:ffffc900030274b0 EFLAGS: 00010286
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81e53a84 RDI: dffffc0000000028
RBP: 0000000000000140 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff81e53a84
R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000000
FS: 00007f68146b06c0(0000) GS:ffff8880d60dc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33a63fff CR3: 000000002ca1c000 CR4: 0000000000352ef0
Call Trace:
<TASK>
__kasan_check_byte+0x13/0x50 mm/kasan/common.c:573
kasan_check_byte include/linux/kasan.h:402 [inline]
lock_acquire kernel/locking/lockdep.c:5842 [inline]
lock_acquire+0x132/0x370 kernel/locking/lockdep.c:5825
down_write_nested+0x94/0x200 kernel/locking/rwsem.c:1757
inode_lock_nested include/linux/fs.h:1069 [inline]
__start_dirop fs/namei.c:2918 [inline]
start_dirop+0x4b/0xb0 fs/namei.c:2942
simple_start_creating+0xf9/0x110 fs/libfs.c:2305
debugfs_start_creating.part.0+0x82/0x170 fs/debugfs/inode.c:394
debugfs_start_creating fs/debugfs/inode.c:371 [inline]
debugfs_create_dir+0x72/0x440 fs/debugfs/inode.c:572
i2c_device_probe+0x5f5/0xd10 drivers/i2c/i2c-core-base.c:588
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
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3772
i2c_new_client_device+0x660/0xd30 drivers/i2c/i2c-core-base.c:1019
new_device_store+0x20f/0x420 drivers/i2c/i2c-core-base.c:1307
dev_attr_store+0x58/0x80 drivers/base/core.c:2505
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: 0033:0x7f681379de99
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:00007f68146b0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f6813a25fa0 RCX: 00007f681379de99
RDX: 000000000000000c RSI: 0000200000000280 RDI: 0000000000000004
RBP: 00007f6813833eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6813a26038 R14: 00007f6813a25fa0 R15: 00007fff65603768
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kasan_byte_accessible+0x15/0x30 mm/kasan/generic.c:210
Code: 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 b8 00 00 00 00 00 fc ff df 48 c1 ef 03 48 01 c7 <0f> b6 07 3c 07 0f 96 c0 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00
RSP: 0018:ffffc900030274b0 EFLAGS: 00010286
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81e53a84 RDI: dffffc0000000028
RBP: 0000000000000140 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff81e53a84
R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000000
FS: 00007f68146b06c0(0000) GS:ffff8880d60dc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33a63fff CR3: 000000002ca1c000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 0f 1f 00 nopl (%rax)
5: 90 nop
6: 90 nop
7: 90 nop
8: 90 nop
9: 90 nop
a: 90 nop
b: 90 nop
c: 90 nop
d: 90 nop
e: 90 nop
f: 90 nop
10: 90 nop
11: 90 nop
12: 90 nop
13: 90 nop
14: 90 nop
15: 0f 1f 40 d6 nopl -0x2a(%rax)
19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
20: fc ff df
23: 48 c1 ef 03 shr $0x3,%rdi
27: 48 01 c7 add %rax,%rdi
* 2a: 0f b6 07 movzbl (%rdi),%eax <-- trapping instruction
2d: 3c 07 cmp $0x7,%al
2f: 0f 96 c0 setbe %al
32: c3 ret
33: cc int3
34: cc int3
35: cc int3
36: cc int3
37: 66 data16
38: 66 data16
39: 2e cs
3a: 0f .byte 0xf
3b: 1f (bad)
3c: 84 00 test %al,(%rax)


---
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***

Subject: #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git fc02acf6ac0ccde0c805c2daa9148683cdd01ba8
Author: dman...@yandex.ru

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git fc02acf6ac0ccde0c805c2daa9148683cdd01ba8

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
INFO: task hung in dvb_usb_i2c_exit

INFO: task kworker/1:5:6361 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:5 state:D stack:22408 pid:6361 tgid:6361 ppid:2 task_flags:0x4288060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121
i2c_del_adapter+0x1a6/0x2d0 drivers/i2c/i2c-core-base.c:1838
dvb_usb_i2c_exit+0x9f/0xf0 drivers/media/usb/dvb-usb/dvb-usb-i2c.c:46
dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:144 [inline]
dvb_usb_device_exit+0x313/0x520 drivers/media/usb/dvb-usb/dvb-usb-init.c:338
usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:618 [inline]
device_remove+0x12a/0x180 drivers/base/dd.c:610
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
device_del+0x376/0x9b0 drivers/base/core.c:3961
usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345
hub_port_connect drivers/usb/core/hub.c:5407 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x1c4f/0x4a60 drivers/usb/core/hub.c:5953
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>

Showing all locks held in the system:
6 locks held by kworker/3:0/34:
#0: ffff8880231d9940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc900006dfd08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88802cd341d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88802cd341d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4a60 drivers/usb/core/hub.c:5899
#3: ffff88802cd49568 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline]
#3: ffff88802cd49568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
#3: ffff88802cd49568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#3: ffff88802cd49568 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#3: ffff88802cd49568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2b25/0x4a60 drivers/usb/core/hub.c:5953
#4: ffff88802cf28560 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline]
#4: ffff88802cf28560 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#4: ffff88802cf28560 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#4: ffff88802cf28560 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2b4e/0x4a60 drivers/usb/core/hub.c:5953
#5: ffffffff90055328 (ehci_cf_port_reset_rwsem){++++}-{4:4}, at: hub_port_reset+0x1a1/0x1bd0 drivers/usb/core/hub.c:3067
1 lock held by khungtaskd/43:
#0: ffffffff8ebe8180 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8ebe8180 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8ebe8180 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/2:1/58:
#0: ffff8880231d9940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90000abfd08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88816dbd21d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88816dbd21d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4a60 drivers/usb/core/hub.c:5899
5 locks held by kworker/0:2/847:
2 locks held by getty/5534:
#0: ffff88802bc640a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900033832e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
5 locks held by kworker/1:5/6361:
#0: ffff8880231d9940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc9000291fd08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88802ca3b1d8 (
&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4a60 drivers/usb/core/hub.c:5899
#3: ffff888035c711d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#3: ffff888035c711d8 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336
#4: ffff888035c761a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff888035c761a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
#4: ffff888035c761a0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369
4 locks held by udevd/6479:
#0: ffff88802dfe4638 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1: ffff88803ea13480 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:165
#2: ffff88805886f878 (kn->active#19){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff88805886f878 (kn->active#19){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:166
#3: ffff888035c711d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1107 [inline]
#3: ffff888035c711d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 43 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)

Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014

Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Sending NMI from CPU 1 to CPUs 0,2-3:
NMI backtrace for cpu 3
CPU: 3 UID: 0 PID: 34 Comm: kworker/3:0 Not tainted syzkaller #0 PREEMPT(full)

Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014

Workqueue: usb_hub_wq hub_event
RIP: 0010:set_idle_cores kernel/sched/fair.c:8425 [inline]
RIP: 0010:select_idle_cpu kernel/sched/fair.c:8597 [inline]
RIP: 0010:select_idle_sibling kernel/sched/fair.c:8909 [inline]
RIP: 0010:select_task_rq_fair+0x2ef3/0x5400 kernel/sched/fair.c:9606
Code: 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 4d 1c 00 00 49 8b 84 24 40 0d 00 00 89 6c 24 50 45 89 f5 48 89 44 24 48 e9 9f e8 ff ff <48> c7 c3 a8 86 64 94 48 83 7c 24 10 08 0f 83 67 1f 00 00 48 b8 00
RSP: 0018:ffffc900006f8be8 EFLAGS: 00000002
RAX: 0000000000000004 RBX: ffff88806a7243f8 RCX: 0000000000000040
RDX: 0000000000000000 RSI: 1ffff1100d4e487f RDI: ffff88806a7243f8
RBP: ffffffff91227dc0 R08: ffff88806a7243f8 R09: ffff88806a620c88
R10: dffffc0000000000 R11: 0000000000000000 R12: 0000000000000004
R13: 0000000000000002 R14: 0000000000000003 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880d60dc000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000559b350e0608 CR3: 0000000035096000 CR4: 0000000000352ef0
Call Trace:
<IRQ>
select_task_rq kernel/sched/core.c:3619 [inline]
try_to_wake_up+0xaa2/0x1c90 kernel/sched/core.c:4393
hrtimer_wakeup+0x47/0x60 kernel/time/hrtimer.c:2293
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline]
RIP: 0010:vprintk_emit+0x553/0x6b0 kernel/printk/printk.c:2478
Code: 00 4d 85 ed 0f 85 1b 01 00 00 e8 38 af 21 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 c6 a9 21 00 48 85 ed 0f 85 27 01 00 00 <e8> 18 af 21 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00
RSP: 0018:ffffc900006df518 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 000000000000003d RCX: ffffffff81e8b23a
RDX: ffff88801f6ca540 RSI: ffffffff81e8b244 RDI: ffff88801f6ca540
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff920000dbea5
R13: 0000000000000200 R14: ffff88801cfb8000 R15: ffffc900006df6d8
dev_vprintk_emit+0x391/0x3e0 drivers/base/core.c:4996
dev_printk_emit+0xd2/0x10d drivers/base/core.c:5007
__dev_printk+0xcb/0x100 drivers/base/core.c:5019
_dev_notice+0xef/0x130 drivers/base/core.c:5064
usb_get_bos_descriptor.cold+0x40/0xb4 drivers/usb/core/config.c:1051
hub_port_init+0x1e37/0x37f0 drivers/usb/core/hub.c:5207
hub_port_connect drivers/usb/core/hub.c:5496 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x2e7d/0x4a60 drivers/usb/core/hub.c:5953
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)

Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014

RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: d6 8b 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d c3 7e 10 00 fb f4 <e9> 3c 4a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e807e10 EFLAGS: 00000206
RAX: 000000000049aca9 RBX: ffffffff8e891480 RCX: ffffffff8bbb22d5
RDX: 0000000000000000 RSI: ffffffff8e1a5f27 RDI: ffffffff8c401680
RBP: fffffbfff1d12290 R08: 0000000000000001 R09: ffffed100d48678d
R10: ffff88806a433c6b R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffffffff1d00fc6 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880d5ddc000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000559b350da038 CR3: 000000002878b000 CR4: 0000000000352ef0
Call Trace:
<TASK>
arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:768
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
rest_init+0x251/0x260 init/main.c:717
start_kernel+0x48e/0x490 init/main.c:1175
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x158
</TASK>
NMI backtrace for cpu 2
CPU: 2 UID: 0 PID: 0 Comm: swapper/2 Not tainted syzkaller #0 PREEMPT(full)

Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014

RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: d6 8b 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d c3 7e 10 00 fb f4 <e9> 3c 4a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000187e00 EFLAGS: 00000206
RAX: 00000000004489e7 RBX: ffff88801eed4a80 RCX: ffffffff8bbb22d5
RDX: 0000000000000000 RSI: ffffffff8e1a5f27 RDI: ffffffff8c401680
RBP: ffffed1003dda950 R08: 0000000000000001 R09: ffffed100d4c678d
R10: ffff88806a633c6b R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffff92000030fc4 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880d5fdc000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000559b350e3038 CR3: 0000000034909000 CR4: 0000000000352ef0
Call Trace:
<TASK>
arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:768
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x158
</TASK>


Tested on:

commit: fc02acf6 Merge tag 'platform-drivers-x86-v7.2-4' of gi..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=133938c6580000

kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=1e3d934ee3cff1ac188b
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

patch: https://syzkaller.appspot.com/x/patch.diff?x=128bf8c6580000

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-...@vger.kernel.org, syzkall...@googlegroups.com.

***

Subject: test
Author: yun....@windriver.com

#syz test

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+1e3d93...@syzkaller.appspotmail.com
Tested-by: syzbot+1e3d93...@syzkaller.appspotmail.com

Tested on:

commit: fc02acf6 Merge tag 'platform-drivers-x86-v7.2-4' of gi..

git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1349a49e580000

kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=1e3d934ee3cff1ac188b
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

patch: https://syzkaller.appspot.com/x/patch.diff?x=171da9b9580000

Note: testing is done by a robot and is best-effort only.

[syzbot]

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+1e3d93...@syzkaller.appspotmail.com
Tested-by: syzbot+1e3d93...@syzkaller.appspotmail.com

Tested on:

commit: fc02acf6 Merge tag 'platform-drivers-x86-v7.2-4' of gi..
git tree: upstream

console output: https://syzkaller.appspot.com/x/log.txt?x=151309b9580000

kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=1e3d934ee3cff1ac188b
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

patch: https://syzkaller.appspot.com/x/patch.diff?x=119338c6580000