syzbot


INFO: task hung in vfs_rename

Status: upstream: reported on 2024/05/12 18:33
Reported-by: syzbot+d64a57305121b7b5bfec@syzkaller.appspotmail.com
First crash: 38d, last: 38d

Sample crash report:
INFO: task syz-executor.3:8461 blocked for more than 144 seconds.
      Not tainted 5.15.158-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:23544 pid: 8461 ppid:  3528 flags:0x00004206
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165
 inode_lock_nested include/linux/fs.h:824 [inline]
 vfs_rename+0x7a2/0x10f0 fs/namei.c:4795
 do_renameat2+0xe0f/0x1700 fs/namei.c:4985
 __do_sys_renameat2 fs/namei.c:5018 [inline]
 __se_sys_renameat2 fs/namei.c:5015 [inline]
 __x64_sys_renameat2+0xce/0xe0 fs/namei.c:5015
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f4801010d69
RSP: 002b:00007f47ff5830c8 EFLAGS: 00000246 ORIG_RAX: 000000000000013c
RAX: ffffffffffffffda RBX: 00007f480113ef80 RCX: 00007f4801010d69
RDX: 000000000000000c RSI: 0000000020000380 RDI: 000000000000000c
RBP: 00007f480105d49e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000200 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f480113ef80 R15: 00007ffe40bd8158
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3257:
 #0: ffff888023fa2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc9000250b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by kworker/u5:2/3522:
 #0: ffff8880730c5138 ((wq_completion)hci8){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90003067d20 ((work_completion)(&hdev->power_on)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff8880658a4ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_open+0xa4/0x1330 net/bluetooth/hci_core.c:1446
3 locks held by kworker/0:10/3603:
 #0: ffff88814278b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90004397d20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff88801e1df2a8 (&dev->power.lock){-.-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:388 [inline]
 #2: ffff88801e1df2a8 (&dev->power.lock){-.-.}-{2:2}, at: rpm_idle+0x4c9/0x8b0 drivers/base/power/runtime.c:497
3 locks held by kworker/u4:12/3873:
 #0: ffff888011dcd138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90004d27d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8c923fb0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:4039
5 locks held by syz-executor.3/8461:
 #0: ffff88807705c460 (sb_writers#24){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377
 #1: ffff88807705c748 (&type->s_vfs_rename_key){+.+.}-{3:3}, at: lock_rename fs/namei.c:3016 [inline]
 #1: ffff88807705c748 (&type->s_vfs_rename_key){+.+.}-{3:3}, at: do_renameat2+0x5b7/0x1700 fs/namei.c:4924
 #2: ffff888056e60930 (&sb->s_type->i_mutex_key#32/1){+.+.}-{3:3}, at: lock_rename fs/namei.c:3017 [inline]
 #2: ffff888056e60930 (&sb->s_type->i_mutex_key#32/1){+.+.}-{3:3}, at: do_renameat2+0x644/0x1700 fs/namei.c:4924
 #3: ffff888056e60fb0 (&sb->s_type->i_mutex_key#33/5){+.+.}-{3:3}, at: do_renameat2+0x67e/0x1700 fs/namei.c:4924
 #4: ffff888056e60fb0 (&sb->s_type->i_mutex_key#34/2){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline]
 #4: ffff888056e60fb0 (&sb->s_type->i_mutex_key#34/2){+.+.}-{3:3}, at: vfs_rename+0x7a2/0x10f0 fs/namei.c:4795
1 lock held by syz-executor.3/10110:
 #0: ffff888056aac098 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:300 [inline]
 #0: ffff888056aac098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:363 [inline]
 #0: ffff888056aac098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:377 [inline]
 #0: ffff888056aac098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0x10c/0x200 drivers/tty/tty_ldisc.c:802
3 locks held by kworker/1:20/10111:
 #0: ffff888011c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90002d87d20 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8c923fb0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:4039
3 locks held by syz-executor.1/10197:
 #0: ffffffff8ce01808 (uuid_mutex){+.+.}-{3:3}, at: btrfs_mount_root+0x27b/0x930 fs/btrfs/super.c:1709
 #1: ffff88801b07f118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912
 #2: ffff88801b06f468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070
2 locks held by syz-executor.2/10205:
 #0: ffff88801b0cb918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912
 #1: ffff8881478aa468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.158-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10197 Comm: syz-executor.1 Not tainted 5.15.158-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:io_serial_in+0x72/0xb0 drivers/tty/serial/8250/8250_port.c:461
Code: f4 ac 05 fd 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 f5 84 4f fd 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 89 e9 80 e1 07 38 c1 7c ad 48 89 ef
RSP: 0018:ffffc9000303ef70 EFLAGS: 00000002
RAX: 1ffffffff22e2e00 RBX: ffffffff91717780 RCX: 0000000000000000
RDX: 00000000000003fd RSI: 000000000003ffff RDI: 0000000000040000
RBP: 0000000000000000 R08: ffffffff847aafc2 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffffffff22e2f3d
R13: ffffffff91717740 R14: 00000000000003fd R15: dffffc0000000000
FS:  00007f42507216c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00155f0d0 CR3: 00000000770a9000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 serial_in drivers/tty/serial/8250/8250.h:116 [inline]
 wait_for_xmitr+0xec/0x260 drivers/tty/serial/8250/8250_port.c:2069
 serial8250_console_putchar+0x19/0x50 drivers/tty/serial/8250/8250_port.c:3301
 uart_console_write+0xa9/0x100 drivers/tty/serial/serial_core.c:1971
 serial8250_console_write+0xc8e/0x1180 drivers/tty/serial/8250/8250_port.c:3378
 console_unlock+0xced/0x12b0 kernel/printk/printk.c:2744
 vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
 _printk+0xd1/0x120 kernel/printk/printk.c:2299
 btrfs_printk+0x4d2/0x510 fs/btrfs/super.c:245
 btrfs_init_csum_hash fs/btrfs/disk-io.c:2348 [inline]
 open_ctree+0xd5b/0x3500 fs/btrfs/disk-io.c:3234
 btrfs_fill_super+0x1c7/0x2d0 fs/btrfs/super.c:1387
 btrfs_mount_root+0x803/0x930 fs/btrfs/super.c:1752
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1517
 fc_mount fs/namespace.c:1000 [inline]
 vfs_kern_mount+0xb8/0x150 fs/namespace.c:1030
 btrfs_mount+0x395/0xb40 fs/btrfs/super.c:1812
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1517
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f42521b046a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4250720ef8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f4250720f80 RCX: 00007f42521b046a
RDX: 0000000020005100 RSI: 0000000020000040 RDI: 00007f4250720f40
RBP: 0000000020005100 R08: 00007f4250720f80 R09: 0000000000800810
R10: 0000000000800810 R11: 0000000000000202 R12: 0000000020000040
R13: 00007f4250720f40 R14: 00000000000050f9 R15: 0000000020000080
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/12 18:32 linux-5.15.y 284087d4f7d5 9026e142 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in vfs_rename
* Struck through repros no longer work on HEAD.