syzbot


INFO: task hung in do_rmdir

Status: upstream: reported on 2022/07/13 04:55
Reported-by: syzbot+284e25368ab61e50af68@syzkaller.appspotmail.com
First crash: 83d, last: 83d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in do_rmdir (3) 10 580d 656d 0/24 auto-closed as invalid on 2021/06/01 08:24
android-49 INFO: task hung in do_rmdir 1 1606d 1606d 0/3 auto-closed as invalid on 2019/02/22 12:59
upstream INFO: task hung in do_rmdir (4) 1 239d 239d 0/24 auto-closed as invalid on 2022/05/08 10:41
upstream INFO: task hung in do_rmdir (2) 3 1364d 1498d 0/24 closed as dup on 2018/09/11 15:01
upstream INFO: task hung in do_rmdir 1 1652d 1652d 0/24 closed as invalid on 2018/03/27 11:14

Sample crash report:
ieee802154 phy1 wpan1: encryption failed: -22
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
INFO: task syz-executor.1:6673 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.1  D30616  6673  26453 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
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write_nested+0x51/0x90 kernel/locking/rwsem.c:194
 inode_lock_nested include/linux/fs.h:783 [inline]
 do_rmdir+0x255/0x490 fs/namei.c:3931
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fbc821a6109
Code: Bad RIP value.
RSP: 002b:00007fbc80afa168 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 00007fbc822b9030 RCX: 00007fbc821a6109
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000400
RBP: 00007fbc8220005d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe1e42722f R14: 00007fbc80afa300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1570:
 #0: 000000003b23474d (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
1 lock held by in:imklog/7797:
 #0: 000000004a6553c0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
3 locks held by syz-executor.1/6658:
2 locks held by syz-executor.1/6673:
 #0: 00000000257d5d0d (sb_writers#21){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000257d5d0d (sb_writers#21){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 000000009db7741a (&type->i_mutex_dir_key#9/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline]
 #1: 000000009db7741a (&type->i_mutex_dir_key#9/1){+.+.}, at: do_rmdir+0x255/0x490 fs/namei.c:3931

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

NMI backtrace for cpu 0
CPU: 0 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4681 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
RIP: 0010:unwind_next_frame+0x7c2/0x1400 arch/x86/kernel/unwind_orc.c:441
Code: 0f 95 c6 40 84 f7 0f 85 59 09 00 00 83 e0 07 38 c2 40 0f 9e c6 84 d2 0f 95 c0 40 84 c6 0f 85 42 09 00 00 49 0f bf 07 48 01 c8 <48> 89 44 24 68 e9 a8 fe ff ff 49 8d 7e 40 48 b8 00 00 00 00 00 fc
RSP: 0018:ffff8880a14af6c8 EFLAGS: 00000282
RAX: ffff8880a14aff58 RBX: 1ffff11014295ee2 RCX: ffff8880a14aff28
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffff8b8cd908 R09: ffffffff8b8cd904
R10: ffff8880a14af857 R11: 0000000000074071 R12: ffff8880a14af840
R13: ffff8880a14af82d R14: ffff8880a14af7f8 R15: ffffffff8b8cd904
FS:  00007f85e74808c0(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f85e4cd5000 CR3: 00000000a1a61000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44
 save_stack mm/kasan/kasan.c:448 [inline]
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553
 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
 kmem_cache_zalloc include/linux/slab.h:699 [inline]
 __alloc_file+0x21/0x340 fs/file_table.c:100
 alloc_empty_file+0x6d/0x170 fs/file_table.c:150
 path_openat+0xe9/0x2df0 fs/namei.c:3526
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f85e6a0f840
Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24
RSP: 002b:00007ffcfdeea978 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007ffcfdeeac80 RCX: 00007f85e6a0f840
RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000564a0fe100d0
RBP: 000000000000000d R08: 000000000000ffc0 R09: 00000000ffffffff
R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000564a0fe0c040 R14: 00007ffcfdeeac40 R15: 0000564a0fe19270

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2022/07/13 04:55 linux-4.19.y 3f8a27f9e27b d91dd8ea .config log report info INFO: task hung in do_rmdir
* Struck through repros no longer work on HEAD.