syzbot


INFO: task hung in vfs_removexattr

Status: closed as dup on 2018/07/18 11:45
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+9d0373cdac2be4979750@syzkaller.appspotmail.com
First crash: 2089d, last: 1147d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task hung in flush_work v9fs C error 306 2043d 2152d
Discussions (1)
Title Replies (including bot) Last reply
INFO: task hung in vfs_removexattr 2 (3) 2018/07/18 11:45
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 INFO: task hung in vfs_removexattr 2 2064d 2084d 0/3 auto-closed as invalid on 2019/02/22 13:39

Sample crash report:
INFO: task syz-executor.3:11928 blocked for more than 143 seconds.
      Not tainted 5.11.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:27208 pid:11928 ppid:  8465 flags:0x00000004
Call Trace:
 context_switch kernel/sched/core.c:4327 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5078
 schedule+0xcf/0x270 kernel/sched/core.c:5157
 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write_common kernel/locking/rwsem.c:1258 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x132/0x150 kernel/locking/rwsem.c:1407
 inode_lock include/linux/fs.h:773 [inline]
 vfs_removexattr+0xb2/0x240 fs/xattr.c:504
 removexattr+0xc8/0x120 fs/xattr.c:793
 path_removexattr+0x147/0x160 fs/xattr.c:807
 __do_sys_lremovexattr fs/xattr.c:827 [inline]
 __se_sys_lremovexattr fs/xattr.c:824 [inline]
 __x64_sys_lremovexattr+0x52/0x70 fs/xattr.c:824
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x465b09
RSP: 002b:00007f0ae06f1188 EFLAGS: 00000246 ORIG_RAX: 00000000000000c6
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09
RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000020000240
RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fffcfd88d7f R14: 00007f0ae06f1300 R15: 0000000000022000

Showing all locks held in the system:
2 locks held by kworker/u4:5/195:
 #0: ffff8880b9c34d18 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1320 [inline]
 #0: ffff8880b9c34d18 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x217/0x21a0 kernel/sched/core.c:4995
 #1: ffff8880b9c20088 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x305/0x440 kernel/sched/psi.c:833
1 lock held by khungtaskd/1649:
 #0: ffffffff8bd73da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6259
1 lock held by in:imklog/8359:
 #0: ffff88801297a670 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947
2 locks held by syz-executor.3/11928:
 #0: ffff888072ada460 (sb_writers#20){.+.+}-{0:0}, at: path_removexattr+0x9d/0x160 fs/xattr.c:805
 #1: ffff88803958a910 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline]
 #1: ffff88803958a910 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: vfs_removexattr+0xb2/0x240 fs/xattr.c:504
2 locks held by syz-executor.3/11934:
1 lock held by syz-executor.3/11960:
 #0: ffff88803958a910 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline]
 #0: ffff88803958a910 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2198

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

NMI backtrace for cpu 0
CPU: 0 PID: 1649 Comm: khungtaskd Not tainted 5.11.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd43/0xfa0 kernel/hung_task.c:294
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4881 Comm: systemd-journal Not tainted 5.11.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unwind_next_frame+0xc/0x1f90 arch/x86/kernel/unwind_orc.c:418
Code: 74 83 00 48 8b 04 24 eb bd 48 89 0c 24 e8 0c 74 83 00 48 8b 0c 24 e9 72 ff ff ff 0f 1f 00 48 b8 00 00 00 00 00 fc ff df 41 57 <49> 89 ff 41 56 41 55 41 54 55 53 48 81 ec a0 00 00 00 48 c7 44 24
RSP: 0018:ffffc900012dfa90 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: ffffffff81617aa0 RCX: 0000000000000000
RDX: 1ffff9200025bf7e RSI: ffffffff814c1f8e RDI: ffffc900012dfaa0
RBP: ffffc900012dfb28 R08: ffffffff8e259006 R09: 0000000000000001
R10: 0000000000082083 R11: 0000000000000001 R12: ffffc900012dfb58
R13: 0000000000000000 R14: ffff888015dca040 R15: 0000000000000000
FS:  00007fd7d05498c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd7cd97e028 CR3: 000000001534a000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:356
 ____kasan_slab_free+0xb0/0xe0 mm/kasan/common.c:362
 kasan_slab_free include/linux/kasan.h:192 [inline]
 __cache_free mm/slab.c:3424 [inline]
 kmem_cache_free+0x58/0x1c0 mm/slab.c:3697
 __put_cred+0x1de/0x250 kernel/cred.c:148
 put_cred include/linux/cred.h:287 [inline]
 put_cred include/linux/cred.h:280 [inline]
 revert_creds+0x1a8/0x1f0 kernel/cred.c:598
 do_faccessat+0x2ca/0x820 fs/open.c:464
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fd7cf8049c7
Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffcadf82cd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 00007ffcadf85d00 RCX: 00007fd7cf8049c7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055770260f9a3
RBP: 00007ffcadf82e20 R08: 00005577026053e5 R09: 0000000000000018
R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000557702c008c0 R15: 00007ffcadf83310

Crashes (21):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/02/05 05:16 upstream 5c279c4cf206 23a562df .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in vfs_removexattr
2021/02/05 05:06 upstream 5c279c4cf206 23a562df .config console log report info ci-upstream-kasan-gce-root INFO: task hung in vfs_removexattr
2020/12/25 05:45 upstream 3913d00ac51a c2c1d1dd .config console log report info ci-upstream-kasan-gce
2018/12/19 17:24 upstream 62393dbcbe0f fe2dc057 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/05 19:52 upstream d08970904582 ac6c0578 .config console log report ci-upstream-kasan-gce-selinux-root
2018/11/11 18:35 upstream e255aee5b66c 7b5f8621 .config console log report ci-upstream-kasan-gce-root
2018/10/02 20:00 upstream 1d2ba7fee28b a316a2af .config console log report ci-upstream-kasan-gce-smack-root
2018/08/22 21:11 upstream ad1d69735878 95b5c82b .config console log report ci-upstream-kasan-gce-root
2018/08/21 21:03 upstream 778a33959a8a 95b5c82b .config console log report ci-upstream-kasan-gce-root
2018/08/11 14:29 upstream f313b43be461 7a88b141 .config console log report ci-upstream-kasan-gce-root
2018/08/11 04:41 upstream f313b43be461 7a88b141 .config console log report ci-upstream-kasan-gce-root
2018/08/07 23:04 upstream 1236568ee3cb 1beb8136 .config console log report ci-upstream-kasan-gce-root
2018/08/07 09:17 upstream 1236568ee3cb 1beb8136 .config console log report ci-upstream-kasan-gce-root
2018/08/06 19:09 upstream 1ffaddd029c8 1beb8136 .config console log report ci-upstream-kasan-gce-root
2018/07/22 17:15 upstream 45ae4df92207 8cc079c3 .config console log report ci-upstream-kasan-gce-root
2018/07/18 20:15 upstream 04a132065175 809256c3 .config console log report ci-upstream-kasan-gce-root
2018/07/09 14:05 upstream 1e4b044d2251 f25e5770 .config console log report ci-upstream-kasan-gce-root
2021/02/05 05:13 linux-next 0e2c50f40b7f 23a562df .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: task can't die in vfs_removexattr
2019/01/06 15:39 linux-next a4983672f9ca 94f8adb5 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/08/21 01:37 linux-next 812667578394 95b5c82b .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 11:30 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.