====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.3/20123 is trying to acquire lock: 000000006c0326b3 (&nilfs->ns_sem){++++}, at: nilfs_set_error fs/nilfs2/super.c:86 [inline] 000000006c0326b3 (&nilfs->ns_sem){++++}, at: __nilfs_error+0x195/0x401 fs/nilfs2/super.c:131 but task is already holding lock: 00000000f2ad3018 (&dat_lock_key){.+.+}, at: nilfs_get_block+0x18f/0x970 fs/nilfs2/inode.c:79 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&dat_lock_key){.+.+}: nilfs_count_free_blocks+0x68/0x180 fs/nilfs2/the_nilfs.c:698 nilfs_set_log_cursor fs/nilfs2/super.c:237 [inline] nilfs_cleanup_super+0x133/0x490 fs/nilfs2/super.c:319 nilfs_put_super+0x152/0x1a0 fs/nilfs2/super.c:473 generic_shutdown_super+0x144/0x370 fs/super.c:456 kill_block_super+0x97/0xf0 fs/super.c:1185 deactivate_locked_super+0x94/0x160 fs/super.c:329 deactivate_super+0x174/0x1a0 fs/super.c:360 cleanup_mnt+0x1a8/0x290 fs/namespace.c:1098 task_work_run+0x148/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&nilfs->ns_sem){++++}: down_write+0x34/0x90 kernel/locking/rwsem.c:70 nilfs_set_error fs/nilfs2/super.c:86 [inline] __nilfs_error+0x195/0x401 fs/nilfs2/super.c:131 nilfs_bmap_convert_error fs/nilfs2/bmap.c:35 [inline] nilfs_bmap_lookup_contig+0x13d/0x180 fs/nilfs2/bmap.c:95 nilfs_get_block+0x1ce/0x970 fs/nilfs2/inode.c:80 block_truncate_page+0x366/0xb00 fs/buffer.c:2887 nilfs_truncate+0x25d/0x4e0 fs/nilfs2/inode.c:739 nilfs_setattr+0x246/0x2a0 fs/nilfs2/inode.c:835 notify_change+0x70b/0xfc0 fs/attr.c:334 do_truncate+0x134/0x1f0 fs/open.c:63 vfs_truncate+0x54b/0x6d0 fs/open.c:109 do_sys_truncate fs/open.c:132 [inline] do_sys_truncate+0x145/0x170 fs/open.c:120 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&dat_lock_key); lock(&nilfs->ns_sem); lock(&dat_lock_key); lock(&nilfs->ns_sem); *** DEADLOCK *** 5 locks held by syz-executor.3/20123: #0: 0000000056195ee3 (sb_writers#24){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 0000000056195ee3 (sb_writers#24){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360 #1: 0000000030fd352f (&sb->s_type->i_mutex_key#28){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #1: 0000000030fd352f (&sb->s_type->i_mutex_key#28){+.+.}, at: do_truncate+0x125/0x1f0 fs/open.c:61 #2: 00000000ef290d5b (sb_internal#3){.+.+}, at: sb_start_intwrite include/linux/fs.h:1626 [inline] #2: 00000000ef290d5b (sb_internal#3){.+.+}, at: nilfs_transaction_begin+0x1f8/0xa50 fs/nilfs2/segment.c:225 #3: 00000000c96c4bfb (&nilfs->ns_segctor_sem){++++}, at: nilfs_transaction_begin+0x231/0xa50 fs/nilfs2/segment.c:228 #4: 00000000f2ad3018 (&dat_lock_key){.+.+}, at: nilfs_get_block+0x18f/0x970 fs/nilfs2/inode.c:79 stack backtrace: CPU: 0 PID: 20123 Comm: syz-executor.3 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 down_write+0x34/0x90 kernel/locking/rwsem.c:70 nilfs_set_error fs/nilfs2/super.c:86 [inline] __nilfs_error+0x195/0x401 fs/nilfs2/super.c:131 nilfs_bmap_convert_error fs/nilfs2/bmap.c:35 [inline] nilfs_bmap_lookup_contig+0x13d/0x180 fs/nilfs2/bmap.c:95 nilfs_get_block+0x1ce/0x970 fs/nilfs2/inode.c:80 block_truncate_page+0x366/0xb00 fs/buffer.c:2887 nilfs_truncate+0x25d/0x4e0 fs/nilfs2/inode.c:739 nilfs_setattr+0x246/0x2a0 fs/nilfs2/inode.c:835 notify_change+0x70b/0xfc0 fs/attr.c:334 do_truncate+0x134/0x1f0 fs/open.c:63 vfs_truncate+0x54b/0x6d0 fs/open.c:109 do_sys_truncate fs/open.c:132 [inline] do_sys_truncate+0x145/0x170 fs/open.c:120 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fca8852a5a9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fca86e9d168 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007fca8864af80 RCX: 00007fca8852a5a9 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000020000a80 RBP: 00007fca88585580 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdab317cbf R14: 00007fca86e9d300 R15: 0000000000022000 NILFS (loop4): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds NILFS (loop4): bad btree node (ino=16, blocknr=15): level = 0, flags = 0x0, nchildren = 0 NILFS error (device loop4): nilfs_bmap_last_key: broken bmap (inode number=16) Remounting filesystem read-only NILFS (loop4): error -5 truncating bmap (ino=16) Remounting filesystem read-only NILFS (loop3): bad btree node (ino=16, blocknr=15): level = 0, flags = 0x0, nchildren = 0 NILFS error (device loop3): nilfs_bmap_last_key: broken bmap (inode number=16) NILFS (loop3): error -5 truncating bmap (ino=16) NILFS (loop4): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds NILFS (loop4): bad btree node (ino=16, blocknr=15): level = 0, flags = 0x0, nchildren = 0 netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. NILFS error (device loop4): nilfs_bmap_last_key: broken bmap (inode number=16) Remounting filesystem read-only FAT-fs (loop3): bogus number of reserved sectors NILFS (loop4): error -5 truncating bmap (ino=16) FAT-fs (loop3): Can't find a valid FAT filesystem netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 40 bytes leftover after parsing attributes in process `syz-executor.1'. FAT-fs (loop3): Unrecognized mount option "ioch" or missing value NILFS (loop4): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. NILFS (loop4): bad btree node (ino=16, blocknr=15): level = 0, flags = 0x0, nchildren = 0 NILFS error (device loop4): nilfs_bmap_last_key: broken bmap (inode number=16) netlink: 40 bytes leftover after parsing attributes in process `syz-executor.1'. Remounting filesystem read-only NILFS (loop4): error -5 truncating bmap (ino=16) netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. FAT-fs (loop3): bogus number of reserved sectors FAT-fs (loop3): Can't find a valid FAT filesystem netlink: 40 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. FAT-fs (loop3): bogus number of reserved sectors FAT-fs (loop3): Can't find a valid FAT filesystem netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. FAT-fs (loop3): Unrecognized mount option "ioch" or missing value