====================================================== WARNING: possible circular locking dependency detected 4.14.307-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/11804 is trying to acquire lock: (sb_writers#3){.+.+}, at: [] sb_start_write include/linux/fs.h:1551 [inline] (sb_writers#3){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 but task is already holding lock: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] (&ovl_i_mutex_dir_key[depth]){++++}, at: [] chown_common+0x272/0x4b0 fs/open.c:628 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&ovl_i_mutex_dir_key[depth]){++++}: down_write_killable+0x37/0xb0 kernel/locking/rwsem.c:68 iterate_dir+0x387/0x5e0 fs/readdir.c:43 ovl_dir_read fs/overlayfs/readdir.c:306 [inline] ovl_dir_read_merged+0x2c5/0x430 fs/overlayfs/readdir.c:365 ovl_check_empty_dir+0x6e/0x200 fs/overlayfs/readdir.c:870 ovl_check_empty_and_clear+0x72/0xe0 fs/overlayfs/dir.c:306 ovl_rename+0x57d/0xe50 fs/overlayfs/dir.c:959 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+0x5e/0xd3 -> #0 (sb_writers#3){.+.+}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 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_setattr+0x52/0x500 fs/overlayfs/inode.c:38 notify_change+0x56b/0xd10 fs/attr.c:315 chown_common+0x40b/0x4b0 fs/open.c:631 SYSC_fchownat fs/open.c:661 [inline] SyS_fchownat+0xf6/0x190 fs/open.c:641 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ovl_i_mutex_dir_key[depth]); lock(sb_writers#3); lock(&ovl_i_mutex_dir_key[depth]); lock(sb_writers#3); *** DEADLOCK *** 2 locks held by syz-executor.0/11804: #0: (sb_writers#16){.+.+}, at: [] sb_start_write include/linux/fs.h:1551 [inline] #0: (sb_writers#16){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 #1: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] chown_common+0x272/0x4b0 fs/open.c:628 stack backtrace: CPU: 1 PID: 11804 Comm: syz-executor.0 Not tainted 4.14.307-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023 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 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_setattr+0x52/0x500 fs/overlayfs/inode.c:38 notify_change+0x56b/0xd10 fs/attr.c:315 chown_common+0x40b/0x4b0 fs/open.c:631 SYSC_fchownat fs/open.c:661 [inline] SyS_fchownat+0xf6/0x190 fs/open.c:641 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 RIP: 0033:0x7f1ea9e540f9 RSP: 002b:00007f1ea83c6168 EFLAGS: 00000246 ORIG_RAX: 000000000000005c RAX: ffffffffffffffda RBX: 00007f1ea9f73f80 RCX: 00007f1ea9e540f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000280 RBP: 00007f1ea9eafae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcc1e2aeaf R14: 00007f1ea83c6300 R15: 0000000000022000 UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 512 failed UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 1024 failed UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 2048 failed UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 512 failed UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 1024 failed UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 2048 failed UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 512 failed UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 1024 failed UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 2048 failed UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 512 failed UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 1024 failed UDF-fs: warning (device loop3): udf_load_vrs: No VRS found UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) UDF-fs: Scanning with blocksize 2048 failed UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) device bridge1 entered promiscuous mode capability: warning: `syz-executor.0' uses deprecated v2 capabilities in a way that may be insecure netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. device bridge1 entered promiscuous mode bridge1: port 1(syz_tun) entered blocking state UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) bridge1: port 1(syz_tun) entered disabled state device syz_tun entered promiscuous mode device syz_tun left promiscuous mode bridge1: port 1(syz_tun) entered disabled state audit: type=1800 audit(1677553765.324:50): pid=12173 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="sda1" ino=14337 res=0 netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. audit: type=1800 audit(1677553765.324:51): pid=12173 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="sda1" ino=14337 res=0 BTRFS info (device loop1): force zlib compression device bridge1 entered promiscuous mode BTRFS info (device loop1): enabling inode map caching BTRFS warning (device loop1): excessive commit interval 622039222 BTRFS info (device loop1): using free space tree BTRFS info (device loop1): has skinny extents netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'.