possible deadlock in __generic_file_fsync

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    6d5d82417dd6 Add linux-next specific files for 20181016
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=10c8e495400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4e55f86f01cf5131
dashboard link: https://syzkaller.appspot.com/bug?extid=5cd33f0e6abe2bb3e397
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)

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+5cd33f0e6abe2bb3e397@xxxxxxxxxxxxxxxxxxxxxxxxx


======================================================
WARNING: possible circular locking dependency detected
4.19.0-rc8-next-20181016+ #95 Not tainted
------------------------------------------------------
kworker/1:1/22 is trying to acquire lock:
000000009092b9a9 (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock  
include/linux/fs.h:764 [inline]
000000009092b9a9 (&sb->s_type->i_mutex_key#10){++++}, at:  
__generic_file_fsync+0xb5/0x200 fs/libfs.c:999

but task is already holding lock:
000000000349cf73 ((work_completion)(&dio->complete_work)){+.+.}, at:  
process_one_work+0xb9a/0x1c40 kernel/workqueue.c:2128

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env

-> #2 ((work_completion)(&dio->complete_work)){+.+.}:
       process_one_work+0xc0a/0x1c40 kernel/workqueue.c:2129
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
       worker_thread+0x17f/0x1390 kernel/workqueue.c:2296
       kthread+0x35a/0x440 kernel/kthread.c:246
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

-> #1 ((wq_completion)"dio/%s"sb->s_id){+.+.}:
       flush_workqueue+0x30a/0x1e10 kernel/workqueue.c:2655
       drain_workqueue+0x2a9/0x640 kernel/workqueue.c:2820
       destroy_workqueue+0xc6/0x9c0 kernel/workqueue.c:4155
       sb_init_dio_done_wq+0x74/0x90 fs/direct-io.c:634
       dio_set_defer_completion fs/direct-io.c:646 [inline]
       get_more_blocks fs/direct-io.c:723 [inline]
       do_direct_IO fs/direct-io.c:1001 [inline]
       do_blockdev_direct_IO+0x5bd9/0xefa0 fs/direct-io.c:1331
       __blockdev_direct_IO+0x9d/0xc6 fs/direct-io.c:1417
       ext4_direct_IO_write fs/ext4/inode.c:3774 [inline]
       ext4_direct_IO+0xadd/0x2210 fs/ext4/inode.c:3901
       generic_file_direct_write+0x275/0x4b0 mm/filemap.c:2951
       __generic_file_write_iter+0x2ff/0x630 mm/filemap.c:3130
       ext4_file_write_iter+0x390/0x1420 fs/ext4/file.c:266
       call_write_iter include/linux/fs.h:1844 [inline]
       aio_write+0x3b1/0x610 fs/aio.c:1562
       io_submit_one+0xaa1/0xf80 fs/aio.c:1836
       __do_sys_io_submit fs/aio.c:1917 [inline]
       __se_sys_io_submit fs/aio.c:1888 [inline]
       __x64_sys_io_submit+0x1b7/0x580 fs/aio.c:1888
       do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #0 (&sb->s_type->i_mutex_key#10){++++}:
       lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3845
       down_write+0x8a/0x130 kernel/locking/rwsem.c:70
       inode_lock include/linux/fs.h:764 [inline]
       __generic_file_fsync+0xb5/0x200 fs/libfs.c:999
       ext4_sync_file+0xa45/0x1500 fs/ext4/fsync.c:120
       vfs_fsync_range+0x140/0x220 fs/sync.c:197
       generic_write_sync include/linux/fs.h:2776 [inline]
       dio_complete+0x75c/0x9e0 fs/direct-io.c:329
       dio_aio_complete_work+0x20/0x30 fs/direct-io.c:341
       process_one_work+0xc8b/0x1c40 kernel/workqueue.c:2153
       worker_thread+0x17f/0x1390 kernel/workqueue.c:2296
       kthread+0x35a/0x440 kernel/kthread.c:246
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

other info that might help us debug this:

Chain exists of:
  &sb->s_type->i_mutex_key#10 --> (wq_completion)"dio/%s"sb->s_id -->  
(work_completion)(&dio->complete_work)

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((work_completion)(&dio->complete_work));
                               lock((wq_completion)"dio/%s"sb->s_id);
                               lock((work_completion)(&dio->complete_work));
  lock(&sb->s_type->i_mutex_key#10);

 *** DEADLOCK ***

2 locks held by kworker/1:1/22:
 #0: 000000009ad4e495 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at:  
__write_once_size include/linux/compiler.h:206 [inline]
 #0: 000000009ad4e495 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at:  
arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 000000009ad4e495 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at:  
atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 000000009ad4e495 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at:  
atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 000000009ad4e495 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at:  
set_work_data kernel/workqueue.c:617 [inline]
 #0: 000000009ad4e495 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at:  
set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 000000009ad4e495 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at:  
process_one_work+0xb43/0x1c40 kernel/workqueue.c:2124
 #1: 000000000349cf73 ((work_completion)(&dio->complete_work)){+.+.}, at:  
process_one_work+0xb9a/0x1c40 kernel/workqueue.c:2128

stack backtrace:
CPU: 1 PID: 22 Comm: kworker/1:1 Not tainted 4.19.0-rc8-next-20181016+ #95
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Workqueue: dio/sda1 dio_aio_complete_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x244/0x39d lib/dump_stack.c:113
 print_circular_bug.isra.35.cold.54+0x1bd/0x27d  
kernel/locking/lockdep.c:1222
 check_prev_add kernel/locking/lockdep.c:1864 [inline]
 check_prevs_add kernel/locking/lockdep.c:1977 [inline]
 validate_chain kernel/locking/lockdep.c:2348 [inline]
 __lock_acquire+0x3399/0x4c20 kernel/locking/lockdep.c:3342
 lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3845
 down_write+0x8a/0x130 kernel/locking/rwsem.c:70
 inode_lock include/linux/fs.h:764 [inline]
 __generic_file_fsync+0xb5/0x200 fs/libfs.c:999
 ext4_sync_file+0xa45/0x1500 fs/ext4/fsync.c:120
 vfs_fsync_range+0x140/0x220 fs/sync.c:197
 generic_write_sync include/linux/fs.h:2776 [inline]
 dio_complete+0x75c/0x9e0 fs/direct-io.c:329
 dio_aio_complete_work+0x20/0x30 fs/direct-io.c:341
 process_one_work+0xc8b/0x1c40 kernel/workqueue.c:2153
 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296
 kthread+0x35a/0x440 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
audit: type=1804 audit(1539691048.645:329): pid=29314 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/709/bus" dev="sda1"  
ino=16793 res=1
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
audit: type=1804 audit(1539691048.895:330): pid=29314 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/709/bus" dev="sda1"  
ino=16793 res=1
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
audit: type=1804 audit(1539691048.945:331): pid=29316 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/709/bus" dev="sda1"  
ino=16793 res=1
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
audit: type=1804 audit(1539691049.235:332): pid=29353 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/710/bus" dev="sda1"  
ino=16792 res=1
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
audit: type=1804 audit(1539691049.585:333): pid=29353 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/710/bus" dev="sda1"  
ino=16792 res=1
audit: type=1804 audit(1539691049.635:334): pid=29356 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/710/bus" dev="sda1"  
ino=16792 res=1
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
audit: type=1804 audit(1539691049.915:335): pid=29402 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/711/bus" dev="sda1"  
ino=16774 res=1
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'kvm' (00000000cb832808): kobject_uevent_env
kobject: 'kvm' (00000000cb832808): fill_kobj_path: path  
= '/devices/virtual/misc/kvm'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'kvm' (00000000cb832808): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'kvm' (00000000cb832808): fill_kobj_path: path  
= '/devices/virtual/misc/kvm'
kobject: 'kvm' (00000000cb832808): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'kvm' (00000000cb832808): fill_kobj_path: path  
= '/devices/virtual/misc/kvm'
kobject: 'kvm' (00000000cb832808): kobject_uevent_env
kobject: 'kvm' (00000000cb832808): fill_kobj_path: path  
= '/devices/virtual/misc/kvm'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kauditd_printk_skb: 5 callbacks suppressed
audit: type=1804 audit(1539691052.035:341): pid=29544 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/715/bus" dev="sda1"  
ino=16626 res=1
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
audit: type=1804 audit(1539691052.285:342): pid=29544 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/715/bus" dev="sda1"  
ino=16626 res=1
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
audit: type=1804 audit(1539691052.335:343): pid=29544 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/715/bus" dev="sda1"  
ino=16626 res=1
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
audit: type=1804 audit(1539691052.605:344): pid=29577 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/716/bus" dev="sda1"  
ino=16642 res=1
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
audit: type=1804 audit(1539691053.335:345): pid=29586 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/716/bus" dev="sda1"  
ino=16642 res=1
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
audit: type=1804 audit(1539691053.495:346): pid=29629 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/716/bus" dev="sda1"  
ino=16642 res=1
REISERFS warning (device loop3): super-6502 reiserfs_getopt: unknown mount  
option "hash=tea"
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
audit: type=1804 audit(1539691053.785:347): pid=29650 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/717/bus" dev="sda1"  
ino=16627 res=1
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
audit: type=1804 audit(1539691054.055:348): pid=29650 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/717/bus" dev="sda1"  
ino=16627 res=1
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
audit: type=1804 audit(1539691054.115:349): pid=29650 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/717/bus" dev="sda1"  
ino=16627 res=1
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
audit: type=1804 audit(1539691054.385:350): pid=29697 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/718/bus" dev="sda1"  
ino=16627 res=1
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
ceph: device name is missing path (no : separator in /dev/sg0)
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
ceph: device name is missing path (no : separator in /dev/sg0)
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
overlayfs: unrecognized mount option "func=BPRM_CHECK" or missing value
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
overlayfs: unrecognized mount option "func=BPRM_CHECK" or missing value
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
ceph: device name is missing path (no : separator in /dev/sg0)
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
ceph: device name is missing path (no : separator in /dev/sg0)
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
ceph: device name is missing path (no : separator in /dev/sg0)
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
ceph: device name is missing path (no : separator in /dev/sg0)
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kauditd_printk_skb: 13 callbacks suppressed
audit: type=1804 audit(1539691057.335:364): pid=29899 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/723/bus" dev="sda1"  
ino=16525 res=1
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
ceph: device name is missing path (no : separator in /dev/sg0)
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
kobject: 'loop5' (000000003d7cbd7d): kobject_uevent_env
kobject: 'loop5' (000000003d7cbd7d): fill_kobj_path: path  
= '/devices/virtual/block/loop5'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop2' (0000000020f33ae7): kobject_uevent_env
kobject: 'loop2' (0000000020f33ae7): fill_kobj_path: path  
= '/devices/virtual/block/loop2'
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop4' (00000000c7b421aa): kobject_uevent_env
kobject: 'loop4' (00000000c7b421aa): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
kobject: 'loop0' (0000000092021daa): kobject_uevent_env
audit: type=1804 audit(1539691057.605:365): pid=29892 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/723/bus" dev="sda1"  
ino=16525 res=1
kobject: 'loop0' (0000000092021daa): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
kobject: 'loop1' (00000000874f0bf8): kobject_uevent_env
kobject: 'loop1' (00000000874f0bf8): fill_kobj_path: path  
= '/devices/virtual/block/loop1'
audit: type=1804 audit(1539691057.665:366): pid=29907 uid=0 auid=4294967295  
ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers  
comm="syz-executor2"  
name="/root/syzkaller-testdir252511476/syzkaller.X0lV5F/723/bus" dev="sda1"  
ino=16525 res=1
kobject: 'loop3' (000000003d41719b): kobject_uevent_env
kobject: 'loop3' (000000003d41719b): fill_kobj_path: path  
= '/devices/virtual/block/loop3'


---
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