====================================================== WARNING: possible circular locking dependency detected 4.19.125-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.3/1887 is trying to acquire lock: 00000000c1f2fa45 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at: flush_workqueue+0xf7/0x1440 kernel/workqueue.c:2660 FAT-fs (loop2): error, invalid access to FAT (entry 0x00000020) but task is already holding lock: 00000000891b42bf (&sb->s_type->i_mutex_key#9){++++}, at: inode_trylock include/linux/fs.h:768 [inline] 00000000891b42bf (&sb->s_type->i_mutex_key#9){++++}, at: ext4_file_write_iter+0x21f/0xf60 fs/ext4/file.c:238 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sb->s_type->i_mutex_key#9){++++}: inode_lock include/linux/fs.h:748 [inline] __generic_file_fsync+0xb0/0x1f0 fs/libfs.c:987 ext4_sync_file+0xa28/0x1430 fs/ext4/fsync.c:120 vfs_fsync_range+0x138/0x220 fs/sync.c:197 generic_write_sync include/linux/fs.h:2747 [inline] dio_complete+0x47c/0x9e0 fs/direct-io.c:329 process_one_work+0x892/0x1580 kernel/workqueue.c:2155 FAT-fs (loop2): Filesystem has been set read-only worker_thread+0x96/0xe20 kernel/workqueue.c:2298 kthread+0x30b/0x410 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #1 ((work_completion)(&dio->complete_work)){+.+.}: worker_thread+0x96/0xe20 kernel/workqueue.c:2298 FAT-fs (loop2): error, invalid access to FAT (entry 0x00000020) kthread+0x30b/0x410 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #0 ((wq_completion)"dio/%s"sb->s_id){+.+.}: flush_workqueue+0x126/0x1440 kernel/workqueue.c:2663 drain_workqueue+0x1a7/0x460 kernel/workqueue.c:2828 destroy_workqueue+0x75/0x6f0 kernel/workqueue.c:4172 sb_init_dio_done_wq+0x72/0x90 fs/direct-io.c:634 do_blockdev_direct_IO fs/direct-io.c:1284 [inline] __blockdev_direct_IO+0x6445/0xfe24 fs/direct-io.c:1418 ext4_direct_IO_write fs/ext4/inode.c:3769 [inline] ext4_direct_IO+0xa8b/0x1ab0 fs/ext4/inode.c:3902 generic_file_direct_write+0x207/0x490 mm/filemap.c:3065 __generic_file_write_iter+0x2d4/0x610 mm/filemap.c:3244 ext4_file_write_iter+0x2fe/0xf60 fs/ext4/file.c:272 FAT-fs (loop5): error, invalid access to FAT (entry 0x00000020) call_write_iter include/linux/fs.h:1821 [inline] aio_write+0x346/0x530 fs/aio.c:1573 __io_submit_one fs/aio.c:1850 [inline] io_submit_one+0x1005/0x20c0 fs/aio.c:1901 __do_sys_io_submit fs/aio.c:1945 [inline] __se_sys_io_submit+0x142/0x4a0 fs/aio.c:1916 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe attempt to access beyond end of device loop2: rw=34817, want=157, limit=116 other info that might help us debug this: FAT-fs (loop5): Filesystem has been set read-only Chain exists of: (wq_completion)"dio/%s"sb->s_id --> (work_completion)(&dio->complete_work) --> &sb->s_type->i_mutex_key#9 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#9); lock((work_completion)(&dio->complete_work)); lock(&sb->s_type->i_mutex_key#9); FAT-fs (loop5): error, invalid access to FAT (entry 0x00000020) lock((wq_completion)"dio/%s"sb->s_id); *** DEADLOCK *** 1 lock held by syz-executor.3/1887: #0: 00000000891b42bf (&sb->s_type->i_mutex_key#9){++++}, at: inode_trylock include/linux/fs.h:768 [inline] #0: 00000000891b42bf (&sb->s_type->i_mutex_key#9){++++}, at: ext4_file_write_iter+0x21f/0xf60 fs/ext4/file.c:238 stack backtrace: CPU: 0 PID: 1887 Comm: syz-executor.3 Not tainted 4.19.125-syzkaller #0 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+0x1fc/0x2fe lib/dump_stack.c:118 print_circular_bug.isra.0.cold+0x2dc/0x425 kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1865 [inline] check_prevs_add kernel/locking/lockdep.c:1978 [inline] validate_chain kernel/locking/lockdep.c:2419 [inline] __lock_acquire+0x3145/0x4380 kernel/locking/lockdep.c:3415 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907 flush_workqueue+0x126/0x1440 kernel/workqueue.c:2663 attempt to access beyond end of device drain_workqueue+0x1a7/0x460 kernel/workqueue.c:2828 destroy_workqueue+0x75/0x6f0 kernel/workqueue.c:4172 loop5: rw=34817, want=157, limit=116 sb_init_dio_done_wq+0x72/0x90 fs/direct-io.c:634 do_blockdev_direct_IO fs/direct-io.c:1284 [inline] __blockdev_direct_IO+0x6445/0xfe24 fs/direct-io.c:1418 FAT-fs (loop4): error, invalid access to FAT (entry 0x00000020) ext4_direct_IO_write fs/ext4/inode.c:3769 [inline] ext4_direct_IO+0xa8b/0x1ab0 fs/ext4/inode.c:3902 generic_file_direct_write+0x207/0x490 mm/filemap.c:3065 FAT-fs (loop4): Filesystem has been set read-only __generic_file_write_iter+0x2d4/0x610 mm/filemap.c:3244 ext4_file_write_iter+0x2fe/0xf60 fs/ext4/file.c:272 call_write_iter include/linux/fs.h:1821 [inline] aio_write+0x346/0x530 fs/aio.c:1573 FAT-fs (loop4): error, invalid access to FAT (entry 0x00000020) __io_submit_one fs/aio.c:1850 [inline] io_submit_one+0x1005/0x20c0 fs/aio.c:1901 __do_sys_io_submit fs/aio.c:1945 [inline] __se_sys_io_submit+0x142/0x4a0 fs/aio.c:1916 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45ca69 Code: 0d b7 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2ae55ebc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 00000000004e0d40 RCX: 000000000045ca69 RDX: 0000000020000540 RSI: 0000000000000006 RDI: 00007f2ae55a8000 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000001fb R14: 00000000004c4486 R15: 00007f2ae55ec6d4 FAT-fs (loop2): error, invalid access to FAT (entry 0x00000020) FAT-fs (loop2): Filesystem has been set read-only FAT-fs (loop2): error, invalid access to FAT (entry 0x00000020) attempt to access beyond end of device loop2: rw=34817, want=157, limit=116 9pnet: p9_errstr2errno: server reported unknown error áÈ¢Vå Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable 9pnet: p9_errstr2errno: server reported unknown error áÈ¢Vå