syzbot


INFO: task hung in f2fs_ioctl

Status: upstream: reported on 2022/12/27 15:52
Subsystems: f2fs
[Documentation on labels]
Reported-by: syzbot+4b9d087eccf88b4d7b67@syzkaller.appspotmail.com
First crash: 574d, last: 574d

Sample crash report:
INFO: task syz-executor.5:30552 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D24320 30552   8132 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1016 [inline]
 __mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
 f2fs_ioc_gc fs/f2fs/file.c:2102 [inline]
 f2fs_ioctl+0x40c9/0x83f0 fs/f2fs/file.c:2953
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f45b77830a9
Code: Bad RIP value.
RSP: 002b:00007f45b5cf5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f45b78a2f80 RCX: 00007f45b77830a9
RDX: 00000000200000c0 RSI: 000000004004f506 RDI: 0000000000000004
RBP: 00007f45b77deae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff9f92366f R14: 00007f45b5cf5300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1570:
 #0: 00000000484fe263 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
1 lock held by in:imklog/7800:
 #0: 0000000059819a95 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
4 locks held by kworker/u4:6/9390:
 #0: 000000001a58ba41 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124
 #1: 000000009a5ecab3 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128
 #2: 00000000daeca0cd (&type->s_umount_key#92){++++}, at: trylock_super+0x1d/0x100 fs/super.c:412
 #3: 0000000053d27ae8 (&sbi->gc_mutex){+.+.}, at: f2fs_balance_fs+0x709/0xd80 fs/f2fs/segment.c:512
2 locks held by syz-executor.5/30552:
 #0: 000000008bfdcbfd (sb_writers#30){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 000000008bfdcbfd (sb_writers#30){.+.+}, at: mnt_want_write_file+0x63/0x1d0 fs/namespace.c:418
 #1: 0000000053d27ae8 (&sbi->gc_mutex){+.+.}, at: f2fs_ioc_gc fs/f2fs/file.c:2102 [inline]
 #1: 0000000053d27ae8 (&sbi->gc_mutex){+.+.}, at: f2fs_ioctl+0x40c9/0x83f0 fs/f2fs/file.c:2953
2 locks held by syz-executor.5/30599:
3 locks held by syz-executor.2/6883:
 #0: 000000001ca37351 (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline]
 #0: 000000001ca37351 (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:598
 #1: 00000000a45a0fcb (sk_lock-AF_CAN){+.+.}, at: lock_sock include/net/sock.h:1512 [inline]
 #1: 00000000a45a0fcb (sk_lock-AF_CAN){+.+.}, at: bcm_release+0x1ff/0x950 net/can/bcm.c:1558
 #2: 00000000e970396b (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline]
 #2: 00000000e970396b (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x4dc/0x6f0 kernel/rcu/tree_exp.h:667
2 locks held by syz-executor.5/6944:
 #0: 00000000bb89d93d (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1826 [inline]
 #0: 00000000bb89d93d (&rq->lock){-.-.}, at: __schedule+0x1f9/0x2040 kernel/sched/core.c:3455
 #1: 00000000484fe263 (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:428 [inline]
 #1: 00000000484fe263 (rcu_read_lock){....}, at: update_curr+0x2c3/0x870 kernel/sched/fair.c:857

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

NMI backtrace for cpu 1
CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6953 Comm: syz-executor.2 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:__rcu_read_unlock+0x27/0x160 kernel/rcu/tree_plugin.h:421
Code: 00 00 00 48 b8 00 00 00 00 00 fc ff df 55 53 65 48 8b 1c 25 c0 df 01 00 48 8d ab 70 03 00 00 48 89 ea 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e e5 00 00 00 8b 83 70 03 00 00 83 f8 01 74
RSP: 0018:ffff888049a1fad0 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: ffff8880b2b583c0 RCX: ffffffff81d86ddb
RDX: 1ffff1101656b0e6 RSI: ffffffff81d86cc1 RDI: 0000000000000001
RBP: ffff8880b2b58730 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880ae624b28
R13: 0000000000000000 R14: ffff8880a3d1b500 R15: 0000000000000000
FS:  000055555754b400(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055937baf21a8 CR3: 00000000b4485000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rcu_read_unlock include/linux/rcupdate.h:680 [inline]
 ext4_get_group_desc+0x1d6/0x4e0 fs/ext4/balloc.c:284
 recently_deleted fs/ext4/ialloc.c:680 [inline]
 find_inode_bit+0x1a0/0x520 fs/ext4/ialloc.c:724
 __ext4_new_inode+0x160c/0x5a20 fs/ext4/ialloc.c:916
 ext4_symlink+0x3f5/0xc00 fs/ext4/namei.c:3176
 vfs_symlink+0x453/0x6c0 fs/namei.c:4129
 do_symlinkat+0x258/0x2c0 fs/namei.c:4156
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f30563479e7
Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd2a37ce88 EFLAGS: 00000202 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f30563479e7
RDX: 00007f30563a3b8a RSI: 00000000ffffff9c RDI: 00007f30563a2713
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffd2a37c900
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffd2a37cf50
syz-executor.1 (6960): drop_caches: 0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/12/27 15:52 linux-4.19.y 3f8a27f9e27b 44712fbc .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in f2fs_ioctl
* Struck through repros no longer work on HEAD.