FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) ====================================================== WARNING: possible circular locking dependency detected 4.14.210-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.3/26297 is trying to acquire lock: ("dio/%s"sb->s_id){+.+.}, at: [] flush_workqueue+0xcb/0x1310 kernel/workqueue.c:2621 audit: type=1800 audit(1607293739.558:30018): pid=26306 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.4" name="file0" dev="loop4" ino=145 res=0 but task is already holding lock: (&sb->s_type->i_mutex_key#10){++++}, at: [] inode_trylock include/linux/fs.h:739 [inline] (&sb->s_type->i_mutex_key#10){++++}, at: [] ext4_file_write_iter+0x1cc/0xd20 fs/ext4/file.c:236 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sb->s_type->i_mutex_key#10){++++}: down_write+0x34/0x90 kernel/locking/rwsem.c:54 inode_lock include/linux/fs.h:719 [inline] __generic_file_fsync+0x9e/0x190 fs/libfs.c:989 ext4_sync_file+0x8ed/0x12c0 fs/ext4/fsync.c:118 audit: type=1804 audit(1607293739.558:30019): pid=26306 uid=0 auid=0 ses=4 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/598/file0/file0" dev="loop4" ino=145 res=1 vfs_fsync_range+0x103/0x260 fs/sync.c:196 generic_write_sync include/linux/fs.h:2682 [inline] dio_complete+0x561/0x8d0 fs/direct-io.c:330 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 -> #1 ((&dio->complete_work)){+.+.}: process_one_work+0x736/0x14a0 kernel/workqueue.c:2092 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 -> #0 ("dio/%s"sb->s_id){+.+.}: audit: type=1804 audit(1607293739.558:30020): pid=26306 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/598/file0/file0" dev="loop4" ino=145 res=1 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 flush_workqueue+0xfa/0x1310 kernel/workqueue.c:2624 drain_workqueue+0x177/0x3e0 kernel/workqueue.c:2789 destroy_workqueue+0x71/0x710 kernel/workqueue.c:4102 sb_init_dio_done_wq+0x61/0x80 fs/direct-io.c:635 do_blockdev_direct_IO fs/direct-io.c:1286 [inline] __blockdev_direct_IO+0x3dea/0xdc60 fs/direct-io.c:1422 ext4_direct_IO_write fs/ext4/inode.c:3716 [inline] ext4_direct_IO+0x888/0x1b80 fs/ext4/inode.c:3857 audit: type=1804 audit(1607293739.558:30021): pid=26306 uid=0 auid=0 ses=4 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/598/file0/file0" dev="loop4" ino=145 res=1 generic_file_direct_write+0x1df/0x420 mm/filemap.c:2958 __generic_file_write_iter+0x2a2/0x590 mm/filemap.c:3137 ext4_file_write_iter+0x276/0xd20 fs/ext4/file.c:270 call_write_iter include/linux/fs.h:1778 [inline] aio_write+0x2ed/0x560 fs/aio.c:1553 audit: type=1804 audit(1607293739.558:30022): pid=26306 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/598/file0/file0" dev="loop4" ino=145 res=1 io_submit_one fs/aio.c:1641 [inline] do_io_submit+0x847/0x1570 fs/aio.c:1709 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb other info that might help us debug this: audit: type=1804 audit(1607293739.558:30023): pid=26315 uid=0 auid=0 ses=4 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/598/file0/file0" dev="loop4" ino=145 res=1 Chain exists of: "dio/%s"sb->s_id --> (&dio->complete_work) --> &sb->s_type->i_mutex_key#10 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#10); lock((&dio->complete_work)); lock(&sb->s_type->i_mutex_key#10); lock("dio/%s"sb->s_id audit: type=1804 audit(1607293739.558:30024): pid=26317 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/598/file0/file0" dev="loop4" ino=145 res=1 ); *** DEADLOCK *** 2 locks held by syz-executor.3/26297: #0: (sb_writers#3){.+.+}, at: [] file_start_write include/linux/fs.h:2712 [inline] #0: (sb_writers#3){.+.+}, at: [] aio_write+0x408/0x560 fs/aio.c:1552 #1: (&sb->s_type->i_mutex_key#10){++++}, at: [] inode_trylock include/linux/fs.h:739 [inline] #1: (&sb->s_type->i_mutex_key#10){++++}, at: [] ext4_file_write_iter+0x1cc/0xd20 fs/ext4/file.c:236 stack backtrace: CPU: 0 PID: 26297 Comm: syz-executor.3 Not tainted 4.14.210-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: audit: type=1804 audit(1607293739.558:30025): pid=26306 uid=0 auid=0 ses=4 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/598/file0/file0" dev="loop4" ino=145 res=1 __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 audit: type=1804 audit(1607293739.558:30026): pid=26315 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/598/file0/file0" dev="loop4" ino=145 res=1 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 flush_workqueue+0xfa/0x1310 kernel/workqueue.c:2624 drain_workqueue+0x177/0x3e0 kernel/workqueue.c:2789 destroy_workqueue+0x71/0x710 kernel/workqueue.c:4102 sb_init_dio_done_wq+0x61/0x80 fs/direct-io.c:635 do_blockdev_direct_IO fs/direct-io.c:1286 [inline] __blockdev_direct_IO+0x3dea/0xdc60 fs/direct-io.c:1422 ext4_direct_IO_write fs/ext4/inode.c:3716 [inline] ext4_direct_IO+0x888/0x1b80 fs/ext4/inode.c:3857 generic_file_direct_write+0x1df/0x420 mm/filemap.c:2958 __generic_file_write_iter+0x2a2/0x590 mm/filemap.c:3137 ext4_file_write_iter+0x276/0xd20 fs/ext4/file.c:270 call_write_iter include/linux/fs.h:1778 [inline] aio_write+0x2ed/0x560 fs/aio.c:1553 io_submit_one fs/aio.c:1641 [inline] do_io_submit+0x847/0x1570 fs/aio.c:1709 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45e0f9 RSP: 002b:00007f5791d53c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045e0f9 RDX: 0000000020000540 RSI: 0000000000000006 RDI: 00007f5791d31000 RBP: 000000000119bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffd794bfe3f R14: 00007f5791d549c0 R15: 000000000119bf8c FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) audit: type=1800 audit(1607293740.468:30027): pid=26330 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.4" name="file0" dev="loop4" ino=146 res=0 FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) kauditd_printk_skb: 19 callbacks suppressed audit: type=1800 audit(1607293745.538:30047): pid=26421 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.4" name="file0" dev="loop4" ino=149 res=0 audit: type=1804 audit(1607293745.538:30048): pid=26421 uid=0 auid=0 ses=4 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/602/file0/file0" dev="loop4" ino=149 res=1 audit: type=1804 audit(1607293745.538:30049): pid=26421 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/602/file0/file0" dev="loop4" ino=149 res=1 audit: type=1804 audit(1607293745.548:30050): pid=26421 uid=0 auid=0 ses=4 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/602/file0/file0" dev="loop4" ino=149 res=1 audit: type=1804 audit(1607293745.548:30051): pid=26421 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/602/file0/file0" dev="loop4" ino=149 res=1 FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) audit: type=1800 audit(1607293748.538:30052): pid=26471 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.4" name="file0" dev="loop4" ino=150 res=0 audit: type=1804 audit(1607293748.538:30053): pid=26471 uid=0 auid=0 ses=4 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/603/file0/file0" dev="loop4" ino=150 res=1 audit: type=1804 audit(1607293748.538:30054): pid=26471 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/603/file0/file0" dev="loop4" ino=150 res=1 FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) audit: type=1804 audit(1607293748.538:30055): pid=26471 uid=0 auid=0 ses=4 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/603/file0/file0" dev="loop4" ino=150 res=1 Process accounting resumed audit: type=1804 audit(1607293748.538:30056): pid=26471 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir299501926/syzkaller.ps9qwE/603/file0/file0" dev="loop4" ino=150 res=1