NILFS (loop5): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds NILFS (loop5): error -116 getting root inode ====================================================== WARNING: possible circular locking dependency detected 4.14.295-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/11438 is trying to acquire lock: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] (&ovl_i_mutex_dir_key[depth]){++++}, at: [] lookup_slow+0x129/0x400 fs/namei.c:1674 but task is already holding lock: (&oi->lock){+.+.}, at: [] ovl_nlink_start+0x22f/0x460 fs/overlayfs/util.c:523 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&oi->lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 ovl_copy_up_start+0x40/0xe0 fs/overlayfs/util.c:318 ovl_copy_up_one+0x21f/0x910 fs/overlayfs/copy_up.c:631 ovl_copy_up_flags+0xd5/0x120 fs/overlayfs/copy_up.c:686 ovl_open_maybe_copy_up+0xe6/0x130 fs/overlayfs/inode.c:346 ovl_d_real+0xbc/0x350 fs/overlayfs/super.c:88 d_real include/linux/dcache.h:587 [inline] vfs_open+0x19e/0x220 fs/open.c:882 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3571 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #1 (sb_writers#3){.+.+}: percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x64/0x260 fs/super.c:1342 sb_start_write include/linux/fs.h:1551 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 ovl_create_object+0x75/0x1d0 fs/overlayfs/dir.c:538 lookup_open+0x77a/0x1750 fs/namei.c:3241 do_last fs/namei.c:3334 [inline] path_openat+0xe08/0x2970 fs/namei.c:3571 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #0 (&ovl_i_mutex_dir_key[depth]){++++}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:729 [inline] lookup_slow+0x129/0x400 fs/namei.c:1674 lookup_one_len_unlocked+0x3a0/0x410 fs/namei.c:2595 ovl_lower_positive+0x184/0x350 fs/overlayfs/namei.c:783 ovl_rename+0x47c/0xe50 fs/overlayfs/dir.c:968 vfs_rename+0x560/0x1820 fs/namei.c:4498 SYSC_renameat2 fs/namei.c:4646 [inline] SyS_renameat2+0x95b/0xad0 fs/namei.c:4535 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: Chain exists of: &ovl_i_mutex_dir_key[depth] --> sb_writers#3 --> &oi->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&oi->lock); lock(sb_writers#3); lock(&oi->lock); lock(&ovl_i_mutex_dir_key[depth]); *** DEADLOCK *** 8 locks held by syz-executor.2/11438: #0: (sb_writers#17){.+.+}, at: [] sb_start_write include/linux/fs.h:1551 [inline] #0: (sb_writers#17){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 #1: (&type->s_vfs_rename_key#2){+.+.}, at: [] lock_rename+0x54/0x280 fs/namei.c:2889 #2: (&ovl_i_mutex_dir_key[depth]#2/1){+.+.}, at: [] inode_lock_nested include/linux/fs.h:754 [inline] #2: (&ovl_i_mutex_dir_key[depth]#2/1){+.+.}, at: [] lock_rename+0xa0/0x280 fs/namei.c:2893 #3: (&ovl_i_mutex_dir_key[depth]#2/2){+.+.}, at: [] inode_lock_nested include/linux/fs.h:754 [inline] #3: (&ovl_i_mutex_dir_key[depth]#2/2){+.+.}, at: [] lock_rename+0xd4/0x280 fs/namei.c:2894 #4: (&ovl_i_mutex_key[depth]){+.+.}, at: [] inode_lock include/linux/fs.h:719 [inline] #4: (&ovl_i_mutex_key[depth]){+.+.}, at: [] lock_two_nondirectories+0xca/0xf0 fs/inode.c:990 #5: (&ovl_i_mutex_key[depth]/4){+.+.}, at: [] inode_lock_nested include/linux/fs.h:754 [inline] #5: (&ovl_i_mutex_key[depth]/4){+.+.}, at: [] lock_two_nondirectories+0xb2/0xf0 fs/inode.c:992 #6: (sb_writers#3){.+.+}, at: [] sb_start_write include/linux/fs.h:1551 [inline] #6: (sb_writers#3){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 #7: (&oi->lock){+.+.}, at: [] ovl_nlink_start+0x22f/0x460 fs/overlayfs/util.c:523 stack backtrace: CPU: 1 PID: 11438 Comm: syz-executor.2 Not tainted 4.14.295-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 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 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:729 [inline] lookup_slow+0x129/0x400 fs/namei.c:1674 lookup_one_len_unlocked+0x3a0/0x410 fs/namei.c:2595 ovl_lower_positive+0x184/0x350 fs/overlayfs/namei.c:783 ovl_rename+0x47c/0xe50 fs/overlayfs/dir.c:968 vfs_rename+0x560/0x1820 fs/namei.c:4498 SYSC_renameat2 fs/namei.c:4646 [inline] SyS_renameat2+0x95b/0xad0 fs/namei.c:4535 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f5a6477c5a9 RSP: 002b:00007f5a630f0168 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 00007f5a6489df80 RCX: 00007f5a6477c5a9 RDX: 0000000000000000 RSI: 0000000020000240 RDI: 00000000200002c0 RBP: 00007f5a647d7580 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd63e0903f R14: 00007f5a630f0300 R15: 0000000000022000 NILFS (loop5): broken superblock, retrying with spare superblock (blocksize = 1024) NILFS (loop5): error -116 getting root inode NILFS (loop5): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds NILFS (loop5): broken superblock, retrying with spare superblock (blocksize = 1024) NILFS (loop5): error -116 getting root inode NILFS (loop5): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds NILFS (loop5): broken superblock, retrying with spare superblock (blocksize = 1024) do_dccp_setsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app NILFS (loop5): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds NILFS (loop5): error -116 getting root inode nbd: must specify a device to reconfigure do_dccp_setsockopt: sockopt(CHANGE_L/R) is deprecated: fix your app netlink: 32 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor.2'. nbd: must specify at least one socket netlink: 20 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 44 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 28 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 16 bytes leftover after parsing attributes in process `syz-executor.2'. nbd: must specify a size in bytes for the device nbd: must specify an index to disconnect ALSA: mixer_oss: invalid OSS volume '' ALSA: mixer_oss: invalid OSS volume '' nbd: must specify at least one socket netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'.