[v5.15] INFO: task hung in __fdget_pos (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fa3df276cd36 Linux 5.15.155
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1222cb93180000
kernel config: https://syzkaller.appspot.com/x/.config?x=fa45dfd65a261480
dashboard link: https://syzkaller.appspot.com/bug?extid=ca8b153ac7b0881f3d78
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0dc19fc63531/disk-fa3df276.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fae4c89e243a/vmlinux-fa3df276.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a5c832fcb939/Image-fa3df276.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ca8b15...@syzkaller.appspotmail.com

INFO: task syz-executor.2:5499 blocked for more than 143 seconds.
Not tainted 5.15.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack: 0 pid: 5499 ppid: 5329 flags:0x00000005
Call trace:
__switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0xf10/0x1e48 kernel/sched/core.c:6376
schedule+0x11c/0x1c8 kernel/sched/core.c:6459
schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6518
__mutex_lock_common+0xba0/0x2154 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
__fdget_pos+0x128/0x170 fs/file.c:1088
fdget_pos include/linux/file.h:75 [inline]
__do_sys_getdents64 fs/readdir.c:365 [inline]
__se_sys_getdents64 fs/readdir.c:354 [inline]
__arm64_sys_getdents64+0x19c/0x4c4 fs/readdir.c:354
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Showing all locks held in the system:
3 locks held by kworker/u4:0/9:
1 lock held by khungtaskd/27:
#0: ffff800014b114e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
2 locks held by getty/3728:
#0: ffff0000d2c5c098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
#1: ffff80001a39e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:7/4031:
#0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
#1: ffff80001d2a7c00 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
#2: ffff8000149c2390 (umhelper_sem){++++}-{3:3}, at: usermodehelper_read_lock_wait+0x138/0x244 kernel/umh.c:249
2 locks held by kworker/1:16/4590:
#0: ffff0000c0021938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
#1: ffff80001f0d7c00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
3 locks held by syz-executor.0/5209:
3 locks held by syz-executor.2/5494:
1 lock held by syz-executor.2/5499:
#0: ffff0000d38c4d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x128/0x170 fs/file.c:1088
5 locks held by kworker/0:29/8146:
#0: ffff0000c281c938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
#1: ffff80001dc97c00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
#2: ffff0000cece2220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff0000cece2220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1b8/0x46b8 drivers/usb/core/hub.c:5768
#3: ffff0000da2f1220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff0000da2f1220 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0xe4/0x7e8 drivers/usb/core/hub.c:2239
#4: ffff0000c60391a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff0000c60391a8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1044 [inline]
#4: ffff0000c60391a8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xbc/0x6ac drivers/base/dd.c:1259
1 lock held by syz-executor.0/9015:
1 lock held by syz-executor.2/9016:
#0: ffff800016a36228 (rtnl_mutex){+.+.}-{3:3}, at: __netlink_dump_start+0x108/0x6ec net/netlink/af_netlink.c:2348

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



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