Hello,
syzbot found the following crash on:
HEAD commit: 5037be168f0e Merge branch 'for-linus' of git://git.kernel...
git tree: upstream
console output:
https://syzkaller.appspot.com/x/log.txt?x=1633299f800000
kernel config:
https://syzkaller.appspot.com/x/.config?x=4f65cd4286737868
dashboard link:
https://syzkaller.appspot.com/bug?extid=cceec01a3ad095b13177
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
CC: [
linux-...@vger.kernel.org linux-...@vger.kernel.org
vi...@zeniv.linux.org.uk]
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by:
syzbot+cceec0...@syzkaller.appspotmail.com
device ifb0 entered promiscuous mode
INFO: task jbd2/sda1-8:2274 blocked for more than 120 seconds.
Not tainted 4.17.0+ #85
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
jbd2/sda1-8 D17432 2274 2 0x80000000
Call Trace:
context_switch kernel/sched/core.c:2856 [inline]
__schedule+0x801/0x1e30 kernel/sched/core.c:3498
schedule+0xef/0x430 kernel/sched/core.c:3542
io_schedule+0x1c/0x70 kernel/sched/core.c:5165
bit_wait_io+0x18/0x90 kernel/sched/wait_bit.c:207
__wait_on_bit+0xb3/0x130 kernel/sched/wait_bit.c:48
out_of_line_wait_on_bit+0x204/0x3a0 kernel/sched/wait_bit.c:63
wait_on_bit_io include/linux/wait_bit.h:101 [inline]
__wait_on_buffer+0x76/0x90 fs/buffer.c:118
wait_on_buffer include/linux/buffer_head.h:356 [inline]
journal_wait_on_commit_record fs/jbd2/commit.c:174 [inline]
jbd2_journal_commit_transaction+0x655b/0x8c18 fs/jbd2/commit.c:865
kjournald2+0x26c/0xb30 fs/jbd2/journal.c:229
kthread+0x345/0x410 kernel/kthread.c:240
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Showing all locks held in the system:
4 locks held by kworker/u4:0/7:
#0: 0000000058f3729a ((wq_completion)"%s""netns"){+.+.}, at:
__write_once_size include/linux/compiler.h:215 [inline]
#0: 0000000058f3729a ((wq_completion)"%s""netns"){+.+.}, at:
arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: 0000000058f3729a ((wq_completion)"%s""netns"){+.+.}, at: atomic64_set
include/asm-generic/atomic-instrumented.h:40 [inline]
#0: 0000000058f3729a ((wq_completion)"%s""netns"){+.+.}, at:
atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
#0: 0000000058f3729a ((wq_completion)"%s""netns"){+.+.}, at: set_work_data
kernel/workqueue.c:617 [inline]
#0: 0000000058f3729a ((wq_completion)"%s""netns"){+.+.}, at:
set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
#0: 0000000058f3729a ((wq_completion)"%s""netns"){+.+.}, at:
process_one_work+0xaef/0x1b50 kernel/workqueue.c:2116
#1: 000000008293b65b (net_cleanup_work){+.+.}, at:
process_one_work+0xb46/0x1b50 kernel/workqueue.c:2120
#2: 00000000bacd550a (pernet_ops_rwsem){++++}, at: cleanup_net+0x11a/0xb20
net/core/net_namespace.c:490
#3: 000000009e8b8f7d (rcu_sched_state.barrier_mutex){+.+.}, at:
_rcu_barrier+0x142/0x770 kernel/rcu/tree.c:3385
2 locks held by khungtaskd/894:
#0: 00000000cfcb9856 (rcu_read_lock){....}, at:
check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
#0: 00000000cfcb9856 (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60
kernel/hung_task.c:249
#1: 00000000cfcb9856 (rcu_read_lock){....}, at:
debug_show_all_locks+0xc8/0x40c kernel/locking/lockdep.c:4461
2 locks held by rs:main Q:Reg/4399:
#0: 00000000fe221072 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1a9/0x1e0
fs/file.c:766
#1: 00000000dd037f72 (sb_writers#4){.+.+}, at: file_start_write
include/linux/fs.h:2720 [inline]
#1: 00000000dd037f72 (sb_writers#4){.+.+}, at: vfs_write+0x452/0x560
fs/read_write.c:548
1 lock held by rsyslogd/4401:
2 locks held by getty/4491:
#0: 00000000a26ee9d0 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: 00000000caaf6182 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4492:
#0: 000000006bbd81ef (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: 0000000032c80a7e (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4493:
#0: 00000000c1496e92 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: 000000001fbbf4c9 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4494:
#0: 00000000c18d11b3 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: 0000000036551200 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4495:
#0: 00000000d6ad2a13 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: 00000000d5666a86 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4496:
#0: 00000000062b45e5 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: 000000004af414a5 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4497:
#0: 00000000b5d15f49 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
#1: 00000000300d3313 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
3 locks held by syz-executor6/20538:
#0: 00000000dd037f72 (sb_writers#4){.+.+}, at: sb_start_write
include/linux/fs.h:1550 [inline]
#0: 00000000dd037f72 (sb_writers#4){.+.+}, at: mnt_want_write+0x3f/0xc0
fs/namespace.c:386
#1: 00000000daa23cdc (&type->i_mutex_dir_key/1){+.+.}, at:
inode_lock_nested include/linux/fs.h:748 [inline]
#1: 00000000daa23cdc (&type->i_mutex_dir_key/1){+.+.}, at:
do_unlinkat+0x3c4/0xa10 fs/namei.c:4030
#2: 000000005600880b (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock
include/linux/fs.h:713 [inline]
#2: 000000005600880b (&sb->s_type->i_mutex_key#10){++++}, at:
vfs_unlink+0xd1/0x510 fs/namei.c:3972
1 lock held by syz-executor4/22416:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 894 Comm: khungtaskd Not tainted 4.17.0+ #85
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1b9/0x294 lib/dump_stack.c:113
nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline]
check_hung_task kernel/hung_task.c:132 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline]
watchdog+0xc10/0xf60 kernel/hung_task.c:249
kthread+0x345/0x410 kernel/kthread.c:240
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 22416 Comm: syz-executor4 Not tainted 4.17.0+ #85
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:bytes_is_nonzero mm/kasan/kasan.c:167 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/kasan.c:184 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/kasan.c:210 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/kasan.c:241 [inline]
RIP: 0010:check_memory_region_inline mm/kasan/kasan.c:257 [inline]
RIP: 0010:check_memory_region+0x117/0x1b0 mm/kasan/kasan.c:267
Code: 00 4d 85 c0 75 3e 4d 89 e0 49 29 c0 e9 6c ff ff ff 4d 85 c0 74 ba 48
b8 01 00 00 00 00 fc ff df 4d 01 c8 48 01 d8 41 80 39 00 <74> 08 e9 8c 00
00 00 48 89 d8 4c 39 c0 74 97 80 38 00 48 8d 58 01
RSP: 0018:ffff8801ae037120 EFLAGS: 00000046
RAX: ffffed003b5c46d7 RBX: 1ffff1003b5c46d6 RCX: ffffffff81647325
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8801dae236b0
RBP: ffff8801ae037138 R08: ffffed003b5c46d7 R09: ffffed003b5c46d6
R10: ffffed003b5c46d6 R11: ffff8801dae236b3 R12: ffffed003b5c46d7
R13: ffff8801dae236b0 R14: ffff8801ae0371c0 R15: dffffc0000000000
FS: 00007f5a84cbb700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5a84c99db8 CR3: 00000001c2bd1000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:349 [inline]
rcu_is_watching+0x85/0x140 kernel/rcu/tree.c:1035
rcu_read_unlock include/linux/rcupdate.h:683 [inline]
cgroup_account_cputime include/linux/cgroup.h:722 [inline]
update_curr_rt+0x80c/0xd20 kernel/sched/rt.c:969
pick_next_task_rt+0x5b8/0x800 kernel/sched/rt.c:1561
pick_next_task kernel/sched/core.c:3357 [inline]
__schedule+0x137a/0x1e30 kernel/sched/core.c:3472
schedule+0xef/0x430 kernel/sched/core.c:3542
tun_ring_recv drivers/net/tun.c:2163 [inline]
tun_do_read+0x1e54/0x29f0 drivers/net/tun.c:2190
tun_chr_read_iter+0xe5/0x1e0 drivers/net/tun.c:2222
call_read_iter include/linux/fs.h:1780 [inline]
new_sync_read fs/read_write.c:406 [inline]
__vfs_read+0x696/0xa50 fs/read_write.c:418
vfs_read+0x17f/0x3d0 fs/read_write.c:452
ksys_pread64+0x174/0x1a0 fs/read_write.c:626
__do_sys_pread64 fs/read_write.c:636 [inline]
__se_sys_pread64 fs/read_write.c:633 [inline]
__x64_sys_pread64+0x97/0xf0 fs/read_write.c:633
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455a09
Code: 1d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5a84cbac68 EFLAGS: 00000246 ORIG_RAX: 0000000000000011
RAX: ffffffffffffffda RBX: 00007f5a84cbb6d4 RCX: 0000000000455a09
RDX: 00000000000002ae RSI: 0000000020000240 RDI: 0000000000000014
RBP: 000000000072bf50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000054d R14: 00000000006fcfd8 R15: 0000000000000001
---
This bug is generated by a bot. It may contain errors.
See
https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at
syzk...@googlegroups.com.
syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with
syzbot.