syzbot


INFO: task hung in pin_kill

Status: auto-closed as invalid on 2019/02/22 13:39
First crash: 2077d, last: 2077d

Sample crash report:
netlink: 8 bytes leftover after parsing attributes in process `syz-executor4'.
netlink: 8 bytes leftover after parsing attributes in process `syz-executor4'.
binder: BINDER_SET_CONTEXT_MGR already set
binder: 11081:11098 ioctl 40046207 0 returned -16
Process accounting resumed
INFO: task syz-executor0:11102 blocked for more than 140 seconds.
      Not tainted 4.9.119-g92e8704 #22
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D29088 11102   3866 0x00000004
 ffff8801981a6000 ffff8801cfcfcfc0 ffff8801cfcfcfc0 ffff8801cccd3000
 ffff8801db321c18 ffff88019abd7d78 ffffffff839ebdcd ffffffff81235627
 0000000000000000 ffff8801981a68c0 0000000600000007 ffff8801db3224e8
Call Trace:
 [<ffffffff839ed3cf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff8161f578>] pin_kill+0x368/0x630 fs/fs_pin.c:62
 [<ffffffff812f3fa0>] acct_on kernel/acct.c:251 [inline]
 [<ffffffff812f3fa0>] SYSC_acct kernel/acct.c:283 [inline]
 [<ffffffff812f3fa0>] SyS_acct+0x560/0x840 kernel/acct.c:270
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839fccd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/518:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813667bc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813667bc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81426027>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3770:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839fae72>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff821208d2>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor0/11102:
 #0:  (acct_on_mutex){+.+.+.}, at: [<ffffffff812f3ac3>] SYSC_acct kernel/acct.c:282 [inline]
 #0:  (acct_on_mutex){+.+.+.}, at: [<ffffffff812f3ac3>] SyS_acct+0x83/0x840 kernel/acct.c:270
 #1:  (sb_writers#3){.+.+.+}, at: [<ffffffff815e0e3f>] sb_start_write include/linux/fs.h:1573 [inline]
 #1:  (sb_writers#3){.+.+.+}, at: [<ffffffff815e0e3f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391

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

NMI backtrace for cpu 1
CPU: 1 PID: 518 Comm: khungtaskd Not tainted 4.9.119-g92e8704 #22
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8637d08 ffffffff81eb4be9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9bd0 ffff8801d8637d40
 ffffffff81ebfee7 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb4be9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb4be9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebfee7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebfe7a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b9cd4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81366d54>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366d54>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366d54>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366d54>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d0ed>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fce9c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11015 Comm: syz-executor0 Not tainted 4.9.119-g92e8704 #22
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88019877e000 task.stack: ffff8801ca6f0000
RIP: 0010:[<ffffffff811bbfb8>] c [<ffffffff811bbfb8>] preempt_count_add+0xb8/0x170 kernel/sched/core.c:3250
RSP: 0000:ffff8801ca6f75a0  EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 1ffffffff0886880
RDX: 1ffff100330efe40 RSI: ffffffff81f1c62b RDI: ffff88019877f200
RBP: ffff8801ca6f75a0 R08: ffff88019877e938 R09: 0000000000000001
R10: ffff88019877e000 R11: 1ffff100330efd22 R12: ffff8801b7c73ce8
R13: dffffc0000000000 R14: 0000000002420848 R15: ffff8801d9c16548
FS:  00007f635181d700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f0445a000 CR3: 00000001cd2fb000 CR4: 00000000001606f0
Stack:
 ffff8801ca6f75d0c ffffffff812841c7c ffff8801ca6f75d0c ffffea0006c8e400c
 ffff8801b7c73ce8c dffffc0000000000c ffff8801ca6f75e0c ffffffff8127c230c
 ffff8801ca6f7648c ffffffff814391bbc ffffffff81438e70c ffffffff81624533c
Call Trace:
 [<ffffffff812841c7>] rcu_lockdep_current_cpu_online+0x37/0x140 kernel/rcu/tree.c:1104
 [<ffffffff8127c230>] rcu_read_lock_held+0x90/0xc0 kernel/rcu/update.c:295
 [<ffffffff814391bb>] radix_tree_deref_slot include/linux/radix-tree.h:199 [inline]
 [<ffffffff814391bb>] find_get_entry+0x34b/0x540 mm/filemap.c:1095
 [<ffffffff8143a2eb>] pagecache_get_page+0x4b/0x720 mm/filemap.c:1201
 [<ffffffff81625809>] find_or_create_page include/linux/pagemap.h:309 [inline]
 [<ffffffff81625809>] grow_dev_page fs/buffer.c:1005 [inline]
 [<ffffffff81625809>] grow_buffers fs/buffer.c:1078 [inline]
 [<ffffffff81625809>] __getblk_slow fs/buffer.c:1105 [inline]
 [<ffffffff81625809>] __getblk_gfp+0x249/0x710 fs/buffer.c:1386
 [<ffffffff816290ed>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818c4a4b>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818c4a4b>] fat12_ent_bread+0x13b/0x400 fs/fat/fatent.c:75
 [<ffffffff818c7c1c>] fat_ent_read_block fs/fat/fatent.c:441 [inline]
 [<ffffffff818c7c1c>] fat_count_free_clusters+0x44c/0xa50 fs/fat/fatent.c:676
 [<ffffffff818ce0f4>] fat_statfs+0x394/0x4a0 fs/fat/inode.c:815
 [<ffffffff8161e1b3>] statfs_by_dentry+0x133/0x200 fs/statfs.c:60
 [<ffffffff8161e2c3>] vfs_statfs+0x43/0x220 fs/statfs.c:70
 [<ffffffff812f25a4>] check_free_space+0x104/0x350 kernel/acct.c:106
 [<ffffffff812f29e7>] do_acct_process+0x1b7/0x1130 kernel/acct.c:487
 [<ffffffff812f398c>] acct_pin_kill+0x2c/0xe0 kernel/acct.c:171
 [<ffffffff8161f377>] pin_kill+0x167/0x630 fs/fs_pin.c:49
 [<ffffffff8161f8ab>] mnt_pin_kill+0x6b/0x180 fs/fs_pin.c:86
 [<ffffffff815dd4b7>] cleanup_mnt+0x127/0x160 fs/namespace.c:1131
 [<ffffffff815dd576>] __cleanup_mnt+0x16/0x20 fs/namespace.c:1141
 [<ffffffff8119838c>] task_work_run+0x10c/0x180 kernel/task_work.c:116
 [<ffffffff8100559c>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff8100559c>] exit_to_usermode_loop+0xfc/0x120 arch/x86/entry/common.c:161
 [<ffffffff810064d4>] prepare_exit_to_usermode arch/x86/entry/common.c:191 [inline]
 [<ffffffff810064d4>] syscall_return_slowpath arch/x86/entry/common.c:260 [inline]
 [<ffffffff810064d4>] do_syscall_64+0x364/0x490 arch/x86/entry/common.c:287
 [<ffffffff839fccd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: c24 c00 c12 c00 c00 c48 cb8 c00 c00 c00 c00 c00 cfc cff cdf c48 c89 cfa c48 cc1 cea c03 c80 c3c c02 c00 c0f c85 ca4 c00 c00 c00 c49 c89 c9c c24 c00 c12 c00 c00 c5b c41 c5c c<5d> cc3 c48 c8b c45 c00 c48 c8b c58 c08 c48 c89 cdf ce8 c86 c21 c08 c00 c85 cc0 c74 c

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/08/10 05:52 https://android.googlesource.com/kernel/common android-4.9 92e87041ed2d 1fb62d58 .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.