overlayfs: fs on 'file0' does not support file handles, falling back to index=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off. ====================================================== WARNING: possible circular locking dependency detected 4.14.293-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/15222 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_rename+0x164/0xe50 fs/overlayfs/dir.c:939 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 -> #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_xattr_set+0x4d/0x290 fs/overlayfs/inode.c:214 ovl_posix_acl_xattr_set+0x2b7/0x830 fs/overlayfs/super.c:762 __vfs_removexattr+0xcf/0x120 fs/xattr.c:416 __vfs_removexattr_locked+0x12e/0x2f0 fs/xattr.c:448 vfs_removexattr+0xb1/0x210 fs/xattr.c:469 removexattr+0x98/0xe0 fs/xattr.c:763 path_removexattr+0xed/0x100 fs/xattr.c:777 SYSC_lremovexattr fs/xattr.c:797 [inline] SyS_lremovexattr+0x1b/0x30 fs/xattr.c:794 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.5/15222: #0: (sb_writers#18){.+.+}, at: [] sb_start_write include/linux/fs.h:1551 [inline] #0: (sb_writers#18){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 #1: (&type->s_vfs_rename_key#3){+.+.}, 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]#2){+.+.}, at: [] inode_lock include/linux/fs.h:719 [inline] #4: (&ovl_i_mutex_key[depth]#2){+.+.}, at: [] lock_two_nondirectories+0xca/0xf0 fs/inode.c:990 #5: (&ovl_i_mutex_key[depth]#2/4){+.+.}, at: [] inode_lock_nested include/linux/fs.h:754 [inline] #5: (&ovl_i_mutex_key[depth]#2/4){+.+.}, 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: 0 PID: 15222 Comm: syz-executor.5 Not tainted 4.14.293-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 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: 0033:0x7fb293437409 RSP: 002b:00007fb291dac168 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 00007fb293549f80 RCX: 00007fb293437409 RDX: 0000000000000000 RSI: 0000000020000240 RDI: 00000000200002c0 RBP: 00007fb293492367 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd8f05d12f R14: 00007fb291dac300 R15: 0000000000022000 overlayfs: fs on 'file0' does not support file handles, falling back to index=off. overlayfs: fs on 'file0' does not support file handles, falling back to index=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off. overlayfs: fs on 'file0' does not support file handles, falling back to index=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off. overlayfs: fs on 'file0' does not support file handles, falling back to index=off. overlayfs: fs on 'file0' does not support file handles, falling back to index=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off. overlayfs: fs on 'file0' does not support file handles, falling back to index=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off. nla_parse: 4 callbacks suppressed netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. device veth3 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth3: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. device veth5 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth5: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. device veth9 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth9: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. device veth7 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth7: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. device veth11 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth11: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'. device veth5 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth5: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. device veth9 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth9: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. device veth13 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth13: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'. device veth7 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth7: link is not ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'. device veth9 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): veth9: link is not ready unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1