syzbot


INFO: task hung in lock_mount (3)

Status: auto-closed as invalid on 2021/06/09 16:09
Reported-by: syzbot+700632128bf349ed2e18@syzkaller.appspotmail.com
First crash: 1254d, last: 1254d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in lock_mount (4) 6 975d 1089d 0/1 auto-closed as invalid on 2022/03/15 09:18
android-49 INFO: task hung in lock_mount C 103 1807d 1924d 0/3 public: reported C repro on 2019/04/11 08:44
linux-5.15 INFO: task hung in lock_mount origin:upstream C error 1 83d 83d 0/3 upstream: reported C repro on 2024/04/25 09:15
linux-4.19 INFO: task hung in lock_mount 5 1650d 1781d 0/1 auto-closed as invalid on 2020/05/09 01:51
upstream INFO: task hung in lock_mount nilfs C error error 1238 455d 2270d 22/27 fixed on 2023/06/08 14:41
linux-4.19 INFO: task hung in lock_mount (2) 2 1487d 1494d 0/1 auto-closed as invalid on 2020/10/18 21:28
android-44 INFO: task hung in lock_mount C 4 2204d 1922d 0/2 public: reported C repro on 2019/04/13 00:00
linux-4.14 INFO: task hung in lock_mount 2 1682d 1683d 0/1 auto-closed as invalid on 2020/04/07 06:26
upstream INFO: task can't die in lock_mount fs C 75 968d 1306d 0/27 closed as dup on 2021/01/18 10:01
upstream INFO: task can't die in iget5_locked fuse 7 1239d 1263d 20/27 fixed on 2021/04/09 19:46

Sample crash report:
wlan1: No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)
wlan1: No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)
wlan1: No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)
INFO: task syz-executor.3:28947 blocked for more than 140 seconds.
      Not tainted 4.19.172-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D28016 28947   8118 0x00000004
Call Trace:
 context_switch syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:3561
 __rwsem_down_write_failed_common syzkaller/managers/linux-4-19/kernel/kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 syzkaller/managers/linux-4-19/kernel/kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 syzkaller/managers/linux-4-19/kernel/arch/x86/lib/rwsem.S:117
 __down_write syzkaller/managers/linux-4-19/kernel/./arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0x4f/0x90 syzkaller/managers/linux-4-19/kernel/kernel/locking/rwsem.c:72
 inode_lock syzkaller/managers/linux-4-19/kernel/./include/linux/fs.h:748 [inline]
 lock_mount+0xcc/0x4a0 syzkaller/managers/linux-4-19/kernel/fs/namespace.c:2039
 do_add_mount+0x73/0x560 syzkaller/managers/linux-4-19/kernel/fs/namespace.c:2416
 do_new_mount syzkaller/managers/linux-4-19/kernel/fs/namespace.c:2483 [inline]
 do_mount+0x1956/0x2f10 syzkaller/managers/linux-4-19/kernel/fs/namespace.c:2799
 ksys_mount+0xcf/0x130 syzkaller/managers/linux-4-19/kernel/fs/namespace.c:3015
 __do_sys_mount syzkaller/managers/linux-4-19/kernel/fs/namespace.c:3029 [inline]
 __se_sys_mount syzkaller/managers/linux-4-19/kernel/fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 syzkaller/managers/linux-4-19/kernel/fs/namespace.c:3026
 do_syscall_64+0xf9/0x620 syzkaller/managers/linux-4-19/kernel/arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x465b09
Code: Bad RIP value.
RSP: 002b:00007f3468b20188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000465b09
RDX: 0000000020000140 RSI: 0000000020000000 RDI: 0000000000000000
RBP: 00000000004b069f R08: 0000000020000580 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008
R13: 00007ffdc8ec029f R14: 00007f3468b20300 R15: 0000000000022000
INFO: task syz-executor.3:29016 blocked for more than 140 seconds.
      Not tainted 4.19.172-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D29144 29016   8118 0x00000004
Call Trace:
 context_switch syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:3561
 __rwsem_down_write_failed_common syzkaller/managers/linux-4-19/kernel/kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 syzkaller/managers/linux-4-19/kernel/kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 syzkaller/managers/linux-4-19/kernel/arch/x86/lib/rwsem.S:117
 __down_write syzkaller/managers/linux-4-19/kernel/./arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0x4f/0x90 syzkaller/managers/linux-4-19/kernel/kernel/locking/rwsem.c:72
 inode_lock syzkaller/managers/linux-4-19/kernel/./include/linux/fs.h:748 [inline]
 vfs_setxattr+0xc7/0x270 syzkaller/managers/linux-4-19/kernel/fs/xattr.c:254
 setxattr+0x23d/0x330 syzkaller/managers/linux-4-19/kernel/fs/xattr.c:520
 path_setxattr+0x170/0x190 syzkaller/managers/linux-4-19/kernel/fs/xattr.c:539
 __do_sys_setxattr syzkaller/managers/linux-4-19/kernel/fs/xattr.c:554 [inline]
 __se_sys_setxattr syzkaller/managers/linux-4-19/kernel/fs/xattr.c:550 [inline]
 __x64_sys_setxattr+0xc0/0x160 syzkaller/managers/linux-4-19/kernel/fs/xattr.c:550
 do_syscall_64+0xf9/0x620 syzkaller/managers/linux-4-19/kernel/arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x465b09
Code: Bad RIP value.
RSP: 002b:00007f3468aff188 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 000000000056c0b0 RCX: 0000000000465b09
RDX: 0000000020000700 RSI: 0000000020000180 RDI: 00000000200002c0
RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000005a R11: 0000000000000246 R12: 000000000056c0b0
R13: 00007ffdc8ec029f R14: 00007f3468aff300 R15: 0000000000022000

Showing all locks held in the system:
2 locks held by kworker/u4:0/7:
1 lock held by khungtaskd/1567:
 #0: 00000000e94038aa (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 syzkaller/managers/linux-4-19/kernel/kernel/locking/lockdep.c:4440
2 locks held by in:imklog/7842:
 #0: 00000000d95425a1 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 syzkaller/managers/linux-4-19/kernel/fs/file.c:767
 #1: 00000000e94038aa (rcu_read_lock){....}, at: rq_lock syzkaller/managers/linux-4-19/kernel/kernel/sched/sched.h:1824 [inline]
 #1: 00000000e94038aa (rcu_read_lock){....}, at: ttwu_queue syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:1841 [inline]
 #1: 00000000e94038aa (rcu_read_lock){....}, at: try_to_wake_up+0x6d0/0x1050 syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:2052
2 locks held by syz-executor.3/28934:
 #0: 0000000079d551ce (sb_writers#17){.+.+}, at: sb_start_write syzkaller/managers/linux-4-19/kernel/./include/linux/fs.h:1579 [inline]
 #0: 0000000079d551ce (sb_writers#17){.+.+}, at: mnt_want_write+0x3a/0xb0 syzkaller/managers/linux-4-19/kernel/fs/namespace.c:360
 #1: 0000000082314b40 (&sb->s_type->i_mutex_key#24){++++}, at: inode_lock syzkaller/managers/linux-4-19/kernel/./include/linux/fs.h:748 [inline]
 #1: 0000000082314b40 (&sb->s_type->i_mutex_key#24){++++}, at: vfs_setxattr+0xc7/0x270 syzkaller/managers/linux-4-19/kernel/fs/xattr.c:254
1 lock held by syz-executor.3/28947:
 #0: 0000000082314b40 (&sb->s_type->i_mutex_key#24){++++}, at: inode_lock syzkaller/managers/linux-4-19/kernel/./include/linux/fs.h:748 [inline]
 #0: 0000000082314b40 (&sb->s_type->i_mutex_key#24){++++}, at: lock_mount+0xcc/0x4a0 syzkaller/managers/linux-4-19/kernel/fs/namespace.c:2039
2 locks held by syz-executor.3/29016:
 #0: 0000000079d551ce (sb_writers#17){.+.+}, at: sb_start_write syzkaller/managers/linux-4-19/kernel/./include/linux/fs.h:1579 [inline]
 #0: 0000000079d551ce (sb_writers#17){.+.+}, at: mnt_want_write+0x3a/0xb0 syzkaller/managers/linux-4-19/kernel/fs/namespace.c:360
 #1: 0000000082314b40 (&sb->s_type->i_mutex_key#24){++++}, at: inode_lock syzkaller/managers/linux-4-19/kernel/./include/linux/fs.h:748 [inline]
 #1: 0000000082314b40 (&sb->s_type->i_mutex_key#24){++++}, at: vfs_setxattr+0xc7/0x270 syzkaller/managers/linux-4-19/kernel/fs/xattr.c:254

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

NMI backtrace for cpu 1
CPU: 1 PID: 1567 Comm: khungtaskd Not tainted 4.19.172-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack syzkaller/managers/linux-4-19/kernel/lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef syzkaller/managers/linux-4-19/kernel/lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 syzkaller/managers/linux-4-19/kernel/lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 syzkaller/managers/linux-4-19/kernel/lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace syzkaller/managers/linux-4-19/kernel/./include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks syzkaller/managers/linux-4-19/kernel/kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 syzkaller/managers/linux-4-19/kernel/kernel/hung_task.c:287
 kthread+0x33f/0x460 syzkaller/managers/linux-4-19/kernel/kernel/kthread.c:259
 ret_from_fork+0x24/0x30 syzkaller/managers/linux-4-19/kernel/arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4675 Comm: systemd-journal Not tainted 4.19.172-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:check_kcov_mode syzkaller/managers/linux-4-19/kernel/kernel/kcov.c:67 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x14/0x50 syzkaller/managers/linux-4-19/kernel/kernel/kcov.c:101
Code: 35 00 e9 23 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 8b 34 24 65 48 8b 04 25 80 df 01 00 65 8b 15 3c 85 9f 7e <81> e2 00 01 1f 00 75 2b 8b 90 60 13 00 00 83 fa 02 75 20 48 8b 88
RSP: 0018:ffff8880a1457a28 EFLAGS: 00000292
RAX: ffff8880a144c140 RBX: dffffc0000000000 RCX: ffffffff816c3cb7
RDX: 0000000080000000 RSI: ffffffff816c0915 RDI: 0000000000000006
RBP: ffff8880a1457b00 R08: 0000000000000000 R09: 00000000000000e8
R10: 0000000000000006 R11: 0000000000000000 R12: ffffffff886fb100
R13: ffffed101428af62 R14: ffffc900019d3120 R15: 00000000000000b6
FS:  00007f2463a698c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f24610cf000 CR3: 00000000a1975000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ___bpf_prog_run+0x45/0x50b0 syzkaller/managers/linux-4-19/kernel/kernel/bpf/core.c:1065

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/02/09 16:09 linux-4.19.y 811218eceeaa 2bd9619f .config console log report info ci2-linux-4-19 INFO: task hung in lock_mount
* Struck through repros no longer work on HEAD.