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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9465fef4ae35 Linux 5.15.153
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1348f12d180000
kernel config: https://syzkaller.appspot.com/x/.config?x=74ff83133fa97f6c
dashboard link: https://syzkaller.appspot.com/bug?extid=7622b68a269cb52839d2
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/3c82fda40b43/disk-9465fef4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ec13893dc103/vmlinux-9465fef4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7b44910e5283/Image-9465fef4.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7622b6...@syzkaller.appspotmail.com

INFO: task syz-executor.4:5895 blocked for more than 143 seconds.
Not tainted 5.15.153-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack: 0 pid: 5895 ppid: 5437 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
rwsem_down_write_slowpath+0xca8/0x1340 kernel/locking/rwsem.c:1157
__down_write_common kernel/locking/rwsem.c:1284 [inline]
__down_write kernel/locking/rwsem.c:1293 [inline]
down_write+0x25c/0x260 kernel/locking/rwsem.c:1542
user_get_super+0xd8/0x240 fs/super.c:835
quotactl_block fs/quota/quota.c:889 [inline]
__do_sys_quotactl fs/quota/quota.c:953 [inline]
__se_sys_quotactl fs/quota/quota.c:915 [inline]
__arm64_sys_quotactl+0x4b0/0x7a4 fs/quota/quota.c:915
__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
INFO: task syz-executor.4:5897 blocked for more than 143 seconds.
Not tainted 5.15.153-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack: 0 pid: 5897 ppid: 5437 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
rwsem_down_write_slowpath+0xca8/0x1340 kernel/locking/rwsem.c:1157
__down_write_common kernel/locking/rwsem.c:1284 [inline]
__down_write kernel/locking/rwsem.c:1293 [inline]
down_write+0x25c/0x260 kernel/locking/rwsem.c:1542
user_get_super+0xd8/0x240 fs/super.c:835
quotactl_block fs/quota/quota.c:889 [inline]
__do_sys_quotactl fs/quota/quota.c:953 [inline]
__se_sys_quotactl fs/quota/quota.c:915 [inline]
__arm64_sys_quotactl+0x4b0/0x7a4 fs/quota/quota.c:915
__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:
1 lock held by khungtaskd/27:
#0: ffff800014ae14a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
2 locks held by kworker/u4:3/296:
2 locks held by getty/3719:
#0: ffff0000d2ff2098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
#1: ffff800018e462e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
5 locks held by syz-executor.0/5122:
4 locks held by syz-executor.4/5249:
1 lock held by syz-executor.4/5895:
#0: ffff0000c19820e0 (&type->s_umount_key#73){+.+.}-{3:3}, at: user_get_super+0xd8/0x240 fs/super.c:835
1 lock held by syz-executor.4/5897:
#0: ffff0000c19820e0 (&type->s_umount_key#73){+.+.}-{3:3}, at: user_get_super+0xd8/0x240 fs/super.c:835
1 lock held by syz-executor.0/6167:
#0: ffff0000d184c0e0 (&type->s_umount_key#73){+.+.}-{3:3}, at: user_get_super+0xd8/0x240 fs/super.c:835
1 lock held by syz-executor.4/6289:
#0: ffff0000c19820e0 (&type->s_umount_key#73){+.+.}-{3:3}, at: user_get_super+0xd8/0x240 fs/super.c:835
1 lock held by syz-executor.0/7878:
#0: ffff0000d184c0e0 (&type->s_umount_key#73){+.+.}-{3:3}, at: user_get_super+0xd8/0x240 fs/super.c:835

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



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