syzbot


INFO: task hung in find_inode_fast

Status: auto-obsoleted due to no activity on 2023/08/23 09:07
Reported-by: syzbot+fbde9841f2c2b9203f16@syzkaller.appspotmail.com
First crash: 314d, last: 296d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in find_inode_fast (2) ext4 C unreliable done 10 78d 232d 26/26 fixed on 2024/01/30 15:47
upstream INFO: task hung in find_inode_fast ext4 C error 28 269d 418d 22/26 fixed on 2023/06/08 14:41

Sample crash report:
INFO: task syz-executor.2:13170 blocked for more than 143 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:25376 pid:13170 ppid:  3554 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 __wait_on_freeing_inode fs/inode.c:2033 [inline]
 find_inode_fast+0x315/0x450 fs/inode.c:869
 iget_locked+0xb2/0x7f0 fs/inode.c:1189
 __ext4_iget+0x25d/0x3e40 fs/ext4/inode.c:4625
 ext4_xattr_inode_cache_find fs/ext4/xattr.c:1509 [inline]
 ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1545 [inline]
 ext4_xattr_set_entry+0x2222/0x3c00 fs/ext4/xattr.c:1686
 ext4_xattr_block_set+0xb10/0x3680 fs/ext4/xattr.c:1992
 ext4_xattr_set_handle+0xdac/0x1560 fs/ext4/xattr.c:2407
 ext4_xattr_set+0x231/0x3d0 fs/ext4/xattr.c:2508
 __vfs_setxattr+0x3e7/0x420 fs/xattr.c:182
 __vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x21d/0x420 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x27e/0x2e0 fs/xattr.c:611
 path_setxattr+0x1bc/0x2a0 fs/xattr.c:630
 __do_sys_setxattr fs/xattr.c:646 [inline]
 __se_sys_setxattr fs/xattr.c:642 [inline]
 __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:642
 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+0x61/0xcb
RIP: 0033:0x7f91423c3169
RSP: 002b:00007f9140935168 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f91424e2f80 RCX: 00007f91423c3169
RDX: 00000000200005c0 RSI: 0000000020000180 RDI: 0000000020000080
RBP: 00007f914241eca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000002000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd7c741a8f R14: 00007f9140935300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.2:13171 blocked for more than 143 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:23512 pid:13171 ppid:  3554 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6514
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1047
 __down_read_common+0x61/0x2c0 kernel/locking/rwsem.c:1231
 ext4_listxattr+0xbe/0xd90 fs/ext4/xattr.c:792
 vfs_listxattr fs/xattr.c:448 [inline]
 listxattr+0x282/0x2e0 fs/xattr.c:783
 path_listxattr fs/xattr.c:807 [inline]
 __do_sys_llistxattr fs/xattr.c:825 [inline]
 __se_sys_llistxattr fs/xattr.c:822 [inline]
 __x64_sys_llistxattr+0x16f/0x230 fs/xattr.c:822
 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+0x61/0xcb
RIP: 0033:0x7f91423c3169
RSP: 002b:00007f9140914168 EFLAGS: 00000246 ORIG_RAX: 00000000000000c3
RAX: ffffffffffffffda RBX: 00007f91424e3050 RCX: 00007f91423c3169
RDX: 0000000000001000 RSI: 0000000020000ec0 RDI: 00000000200001c0
RBP: 00007f914241eca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd7c741a8f R14: 00007f9140914300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.2:13174 blocked for more than 144 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:24024 pid:13174 ppid:  3554 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 mb_cache_entry_wait_unused+0x164/0x240 fs/mbcache.c:148
 ext4_evict_ea_inode+0x146/0x2e0 fs/ext4/xattr.c:460
 ext4_evict_inode+0x17d/0x1100 fs/ext4/inode.c:183
 evict+0x2a4/0x620 fs/inode.c:587
 ext4_xattr_set_entry+0x1d39/0x3c00 fs/ext4/xattr.c:1823
 ext4_xattr_block_set+0x69a/0x3680 fs/ext4/xattr.c:1923
 ext4_xattr_set_handle+0xdac/0x1560 fs/ext4/xattr.c:2407
 ext4_xattr_set+0x231/0x3d0 fs/ext4/xattr.c:2508
 __vfs_setxattr+0x3e7/0x420 fs/xattr.c:182
 __vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x21d/0x420 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x27e/0x2e0 fs/xattr.c:611
 path_setxattr+0x1bc/0x2a0 fs/xattr.c:630
 __do_sys_setxattr fs/xattr.c:646 [inline]
 __se_sys_setxattr fs/xattr.c:642 [inline]
 __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:642
 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+0x61/0xcb
RIP: 0033:0x7f91423c3169
RSP: 002b:00007f9138533168 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f91424e3120 RCX: 00007f91423c3169
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000020000040
RBP: 00007f914241eca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd7c741a8f R14: 00007f9138533300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91c4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by syslogd/2944:
 #0: ffff8880b9a39698 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffff8880b9a27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x53d/0x810 kernel/sched/psi.c:891
2 locks held by getty/3258:
 #0: ffff88814b418098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002bb32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1da0 drivers/tty/n_tty.c:2147
6 locks held by kworker/0:13/26806:
 #0: ffff8880141c4138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279
 #1: ffffc9001017fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281
 #2: ffff88801edd2220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #2: ffff88801edd2220 (&dev->mutex){....}-{3:3}, at: hub_event+0x207/0x56d0 drivers/usb/core/hub.c:5676
 #3: ffff88801edd55c0 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3091 [inline]
 #3: ffff88801edd55c0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5254 [inline]
 #3: ffff88801edd55c0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
 #3: ffff88801edd55c0 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5648 [inline]
 #3: ffff88801edd55c0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x30b9/0x56d0 drivers/usb/core/hub.c:5730
 #4: ffff88801ad65e68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5255 [inline]
 #4: ffff88801ad65e68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
 #4: ffff88801ad65e68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5648 [inline]
 #4: ffff88801ad65e68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x30eb/0x56d0 drivers/usb/core/hub.c:5730
 #5: ffffffff8d37eed0 (ehci_cf_port_reset_rwsem){.+.+}-{3:3}, at: hub_port_reset+0x20a/0x21f0 drivers/usb/core/hub.c:2953
3 locks held by syz-executor.2/13170:
 #0: ffff88802224a460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377
 #1: ffff88803edcf198 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff88803edcf198 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: vfs_setxattr+0x1dd/0x420 fs/xattr.c:302
 #2: ffff88803edcee70 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline]
 #2: ffff88803edcee70 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x270/0x1560 fs/ext4/xattr.c:2322
1 lock held by syz-executor.2/13171:
 #0: ffff88803edcee70 (&ei->xattr_sem){++++}-{3:3}, at: ext4_listxattr+0xbe/0xd90 fs/ext4/xattr.c:792
3 locks held by syz-executor.2/13174:
 #0: ffff88802224a460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377
 #1: ffff88803edcabd0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff88803edcabd0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_setxattr+0x1dd/0x420 fs/xattr.c:302
 #2: ffff88803edca8a8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline]
 #2: ffff88803edca8a8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x270/0x1560 fs/ext4/xattr.c:2322
1 lock held by kworker/u4:10/17078:
 #0: ffff8880b9a39698 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb 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:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 26806 Comm: kworker/0:13 Not tainted 5.15.110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:lock_release+0x6/0x9a0 kernel/locking/lockdep.c:5630
Code: ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 6b fd ff ff 48 89 df e8 eb b9 66 00 e9 5e fd ff ff 66 0f 1f 44 00 00 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 00 01 00 00 49 89 f5 48
RSP: 0018:ffffc9001017f8a8 EFLAGS: 00000093
RAX: ffffffff847a7cdb RBX: ffffffff8c3487e0 RCX: ffff88803b89ba00
RDX: 0000000000000000 RSI: ffffffff847a7cd6 RDI: ffff8880b9a365f0
RBP: ffffc9001017f8b0 R08: ffffffff847a7c7e R09: ffffc9001017f920
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000200
R13: dffffc0000000000 R14: ffffc9001017f980 R15: 1ffff9200202ff20
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b07c9a0018 CR3: 000000001fa33000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 crng_make_state+0x39e/0x690 drivers/char/random.c:392
 _get_random_bytes+0xd3/0x2b0 drivers/char/random.c:405
 eth_random_addr include/linux/etherdevice.h:225 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:674 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:724 [inline]
 nsim_dev_trap_report_work+0x306/0xab0 drivers/net/netdevsim/dev.c:765
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2306
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/10 23:50 linux-5.15.y 8a7f2a5c5aa1 14b12a99 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in find_inode_fast
2023/05/03 04:22 linux-5.15.y 8a7f2a5c5aa1 48e0a81d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in find_inode_fast
2023/04/22 16:34 linux-5.15.y 3299fb36854f 2b32bd34 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: task hung in find_inode_fast
* Struck through repros no longer work on HEAD.