Hello, syzbot found the following issue on: HEAD commit: f9ff5644bcc0 Merge tag 'hsi-for-6.2' of git://git.kernel.o.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15a7ad1b880000 kernel config: https://syzkaller.appspot.com/x/.config?x=c163713cf9186fe7 dashboard link: https://syzkaller.appspot.com/bug?extid=2f73ed585f115e98aee8 compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11d6fe00480000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15d2fc63880000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/95eb66f6b569/disk-f9ff5644.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/fb05e1a5a9de/vmlinux-f9ff5644.xz kernel image: https://storage.googleapis.com/syzbot-assets/e2f1f698973a/bzImage-f9ff5644.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/b52ba015912a/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2f73ed585f115e98aee8@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task kworker/u4:1:11 blocked for more than 143 seconds. Not tainted 6.1.0-syzkaller-13139-gf9ff5644bcc0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:1 state:D stack:18424 pid:11 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:2) Call Trace: <TASK> context_switch kernel/sched/core.c:5244 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6555 schedule+0xcb/0x190 kernel/sched/core.c:6631 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6690 __mutex_lock_common+0xe4f/0x26e0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 write_inode fs/fs-writeback.c:1451 [inline] __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1663 writeback_sb_inodes+0x812/0x1050 fs/fs-writeback.c:1889 __writeback_inodes_wb+0x11d/0x260 fs/fs-writeback.c:1960 wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2065 wb_check_background_flush fs/fs-writeback.c:2131 [inline] wb_do_writeback fs/fs-writeback.c:2219 [inline] wb_workfn+0xb3f/0xef0 fs/fs-writeback.c:2246 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> INFO: task kworker/u4:2:34 blocked for more than 144 seconds. Not tainted 6.1.0-syzkaller-13139-gf9ff5644bcc0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:2 state:D stack:17088 pid:34 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:1) Call Trace: <TASK> context_switch kernel/sched/core.c:5244 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6555 schedule+0xcb/0x190 kernel/sched/core.c:6631 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6690 __mutex_lock_common+0xe4f/0x26e0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 write_inode fs/fs-writeback.c:1451 [inline] __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1663 writeback_sb_inodes+0x812/0x1050 fs/fs-writeback.c:1889 __writeback_inodes_wb+0x11d/0x260 fs/fs-writeback.c:1960 wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2065 wb_check_background_flush fs/fs-writeback.c:2131 [inline] wb_do_writeback fs/fs-writeback.c:2219 [inline] wb_workfn+0xb3f/0xef0 fs/fs-writeback.c:2246 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> INFO: task kworker/u4:5:1065 blocked for more than 145 seconds. Not tainted 6.1.0-syzkaller-13139-gf9ff5644bcc0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:5 state:D stack:22144 pid:1065 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:4) Call Trace: <TASK> context_switch kernel/sched/core.c:5244 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6555 schedule+0xcb/0x190 kernel/sched/core.c:6631 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6690 __mutex_lock_common+0xe4f/0x26e0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 write_inode fs/fs-writeback.c:1451 [inline] __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1663 writeback_sb_inodes+0x812/0x1050 fs/fs-writeback.c:1889 __writeback_inodes_wb+0x11d/0x260 fs/fs-writeback.c:1960 wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2065 wb_check_background_flush fs/fs-writeback.c:2131 [inline] wb_do_writeback fs/fs-writeback.c:2219 [inline] wb_workfn+0xb3f/0xef0 fs/fs-writeback.c:2246 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> INFO: task kworker/u4:0:5140 blocked for more than 145 seconds. Not tainted 6.1.0-syzkaller-13139-gf9ff5644bcc0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:0 state:D stack:21824 pid:5140 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: <TASK> context_switch kernel/sched/core.c:5244 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6555 schedule+0xcb/0x190 kernel/sched/core.c:6631 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6690 __mutex_lock_common+0xe4f/0x26e0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 write_inode fs/fs-writeback.c:1451 [inline] __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1663 writeback_sb_inodes+0x812/0x1050 fs/fs-writeback.c:1889 __writeback_inodes_wb+0x11d/0x260 fs/fs-writeback.c:1960 wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2065 wb_check_background_flush fs/fs-writeback.c:2131 [inline] wb_do_writeback fs/fs-writeback.c:2219 [inline] wb_workfn+0xb3f/0xef0 fs/fs-writeback.c:2246 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> INFO: task kworker/u4:3:5145 blocked for more than 146 seconds. Not tainted 6.1.0-syzkaller-13139-gf9ff5644bcc0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:3 state:D stack:22144 pid:5145 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:3) Call Trace: <TASK> context_switch kernel/sched/core.c:5244 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6555 schedule+0xcb/0x190 kernel/sched/core.c:6631 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6690 __mutex_lock_common+0xe4f/0x26e0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 write_inode fs/fs-writeback.c:1451 [inline] __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1663 writeback_sb_inodes+0x812/0x1050 fs/fs-writeback.c:1889 __writeback_inodes_wb+0x11d/0x260 fs/fs-writeback.c:1960 wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2065 wb_check_background_flush fs/fs-writeback.c:2131 [inline] wb_do_writeback fs/fs-writeback.c:2219 [inline] wb_workfn+0xb3f/0xef0 fs/fs-writeback.c:2246 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> INFO: task kworker/u4:4:5146 blocked for more than 147 seconds. Not tainted 6.1.0-syzkaller-13139-gf9ff5644bcc0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:22144 pid:5146 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:5) Call Trace: <TASK> context_switch kernel/sched/core.c:5244 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6555 schedule+0xcb/0x190 kernel/sched/core.c:6631 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6690 __mutex_lock_common+0xe4f/0x26e0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 write_inode fs/fs-writeback.c:1451 [inline] __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1663 writeback_sb_inodes+0x812/0x1050 fs/fs-writeback.c:1889 __writeback_inodes_wb+0x11d/0x260 fs/fs-writeback.c:1960 wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2065 wb_check_background_flush fs/fs-writeback.c:2131 [inline] wb_do_writeback fs/fs-writeback.c:2219 [inline] wb_workfn+0xb3f/0xef0 fs/fs-writeback.c:2246 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Showing all locks held in the system: 4 locks held by kworker/u4:1/11: #0: ffff8881451dc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc90000107d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 #2: ffff88802bc260e0 (&type->s_umount_key#42){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff888079e060e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d326e50 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x30/0xd00 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d327650 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x30/0xd00 kernel/rcu/tasks.h:507 1 lock held by khungtaskd/28: #0: ffffffff8d326c80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:2/34: #0: ffff8881451dc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc90000ab7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 #2: ffff888022bd40e0 (&type->s_umount_key#42){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88807a1c40e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 4 locks held by kworker/u4:5/1065: #0: ffff8881451dc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc900056dfd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 #2: ffff8880756600e0 (&type->s_umount_key#42){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88802b40c0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 2 locks held by getty/4750: #0: ffff888028235098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900015902f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x53b/0x1650 drivers/tty/n_tty.c:2177 6 locks held by syz-executor402/5133: 6 locks held by syz-executor402/5134: 6 locks held by syz-executor402/5135: 6 locks held by syz-executor402/5136: 6 locks held by syz-executor402/5137: 6 locks held by syz-executor402/5138: 4 locks held by kworker/u4:0/5140: #0: ffff8881451dc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc90003effd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 #2: ffff8880756620e0 (&type->s_umount_key#42){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88807f4ae0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 4 locks held by kworker/u4:3/5145: #0: ffff8881451dc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc90003f1fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 #2: ffff8880757220e0 (&type->s_umount_key#42){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88802b6100e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 4 locks held by kworker/u4:4/5146: #0: ffff8881451dc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc90003f3fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 #2: ffff88802bda60e0 (&type->s_umount_key#42){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88807bd960e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:93 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.0-syzkaller-13139-gf9ff5644bcc0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x290 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46f/0x4f0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ba/0x420 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xcd5/0xd20 kernel/hung_task.c:377 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5133 Comm: syz-executor402 Not tainted 6.1.0-syzkaller-13139-gf9ff5644bcc0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:is_valid_cluster fs/exfat/exfat_fs.h:413 [inline] RIP: 0010:exfat_clear_bitmap+0x85/0x5b0 fs/exfat/balloc.c:171 Code: e8 30 e2 84 ff 4c 8b 3b bf 01 00 00 00 44 89 e6 e8 40 4a 2f ff 41 83 fc 01 0f 86 cb 01 00 00 49 8d 5f 08 48 89 d8 48 c1 e8 03 <42> 8a 04 28 84 c0 0f 85 78 03 00 00 8b 1b 89 df 44 89 e6 e8 93 47 RSP: 0018:ffffc90003b1f838 EFLAGS: 00000a02 RAX: 1ffff1100fe95c01 RBX: ffff88807f4ae008 RCX: 0000000000000000 RDX: ffff88801f718000 RSI: 000000003c2e4184 RDI: 0000000000000001 RBP: ffff888075662000 R08: ffffffff825c8fa0 R09: ffffed100e7265b4 R10: ffffed100e7265b4 R11: 1ffff1100e7265b3 R12: 000000003c2e4184 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88807f4ae000 FS: 000055555561c300(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055d87a197600 CR3: 000000007e2a5000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __exfat_free_cluster+0x470/0x9c0 fs/exfat/fatent.c:192 exfat_free_cluster+0x73/0xc0 fs/exfat/fatent.c:232 __exfat_truncate+0x67e/0x980 fs/exfat/file.c:184 exfat_evict_inode+0xce/0x270 fs/exfat/inode.c:624 evict+0x2a4/0x620 fs/inode.c:664 __dentry_kill+0x3b1/0x5b0 fs/dcache.c:607 dentry_kill+0xbb/0x290 dput+0x1f3/0x410 fs/dcache.c:913 do_renameat2+0xabf/0x12d0 fs/namei.c:4932 __do_sys_rename fs/namei.c:4976 [inline] __se_sys_rename fs/namei.c:4974 [inline] __x64_sys_rename+0x82/0x90 fs/namei.c:4974 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fe1e540ea79 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff21223158 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe1e540ea79 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000020000040 RBP: 0000000000000000 R08: 00007fff21223180 R09: 00007fff21223180 R10: 00007fff21223030 R11: 0000000000000246 R12: 00007fe1e53cd890 R13: 00007fff212231b0 R14: 00007fff21223190 R15: 0000000000000000 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches