syzbot

loop0: detected capacity change from 0 to 40427
F2FS-fs (loop0): Found nat_bits in checkpoint
F2FS-fs (loop0): Mounted with checkpoint version = 48b305e5
======================================================
WARNING: possible circular locking dependency detected
6.1.42-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor166/3540 is trying to acquire lock:
ffff8880719116f8 (&fi->i_sem){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2179 [inline]
ffff8880719116f8 (&fi->i_sem){+.+.}-{3:3}, at: f2fs_add_inline_entry+0x3a4/0x760 fs/f2fs/inline.c:645

but task is already holding lock:
ffff8880719107c0 (&fi->i_xattr_sem){.+.+}-{3:3}, at: f2fs_down_read fs/f2fs/f2fs.h:2154 [inline]
ffff8880719107c0 (&fi->i_xattr_sem){.+.+}-{3:3}, at: f2fs_add_dentry+0x9b/0x1e0 fs/f2fs/dir.c:814

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&fi->i_xattr_sem){.+.+}-{3:3}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
       down_read+0x43/0x2e0 kernel/locking/rwsem.c:1520
       f2fs_down_read fs/f2fs/f2fs.h:2154 [inline]
       f2fs_getxattr+0xb4/0x1460 fs/f2fs/xattr.c:531
       __f2fs_get_acl+0x52/0x8a0 fs/f2fs/acl.c:179
       f2fs_acl_create fs/f2fs/acl.c:375 [inline]
       f2fs_init_acl+0xd3/0x960 fs/f2fs/acl.c:418
       f2fs_init_inode_metadata+0xaa0/0x11d0 fs/f2fs/dir.c:587
       f2fs_add_regular_entry+0x866/0xe00 fs/f2fs/dir.c:771
       f2fs_add_dentry+0xf3/0x1e0 fs/f2fs/dir.c:819
       f2fs_do_add_link+0x21a/0x340 fs/f2fs/dir.c:858
       f2fs_add_link fs/f2fs/f2fs.h:3530 [inline]
       f2fs_mkdir+0x2f1/0x520 fs/f2fs/namei.c:771
       vfs_mkdir+0x3b6/0x590 fs/namei.c:4036
       do_mkdirat+0x260/0x520 fs/namei.c:4061
       __do_sys_mkdir fs/namei.c:4081 [inline]
       __se_sys_mkdir fs/namei.c:4079 [inline]
       __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4079
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&fi->i_sem){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3098 [inline]
       check_prevs_add kernel/locking/lockdep.c:3217 [inline]
       validate_chain+0x1667/0x58e0 kernel/locking/lockdep.c:3832
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       f2fs_down_write fs/f2fs/f2fs.h:2179 [inline]
       f2fs_add_inline_entry+0x3a4/0x760 fs/f2fs/inline.c:645
       f2fs_add_dentry+0xb6/0x1e0 fs/f2fs/dir.c:815
       f2fs_do_add_link+0x21a/0x340 fs/f2fs/dir.c:858
       f2fs_add_link fs/f2fs/f2fs.h:3530 [inline]
       f2fs_mkdir+0x2f1/0x520 fs/f2fs/namei.c:771
       vfs_mkdir+0x3b6/0x590 fs/namei.c:4036
       ovl_do_mkdir fs/overlayfs/overlayfs.h:186 [inline]
       ovl_mkdir_real+0xcf/0x2c0 fs/overlayfs/dir.c:146
       ovl_workdir_create+0x449/0x9d0 fs/overlayfs/super.c:799
       ovl_make_workdir fs/overlayfs/super.c:1389 [inline]
       ovl_get_workdir+0x3b7/0x17b0 fs/overlayfs/super.c:1539
       ovl_fill_super+0x1b85/0x2a20 fs/overlayfs/super.c:2095
       mount_nodev+0x52/0xe0 fs/super.c:1469
       legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
       vfs_get_tree+0x88/0x270 fs/super.c:1553
       do_new_mount+0x28b/0xae0 fs/namespace.c:3040
       do_mount fs/namespace.c:3383 [inline]
       __do_sys_mount fs/namespace.c:3591 [inline]
       __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3568
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&fi->i_xattr_sem);
                               lock(&fi->i_sem);
                               lock(&fi->i_xattr_sem);
  lock(&fi->i_sem);

 *** DEADLOCK ***

5 locks held by syz-executor166/3540:
 #0: ffff88807b4460e0 (&type->s_umount_key#42/1){+.+.}-{3:3}, at: alloc_super+0x217/0x930 fs/super.c:228
 #1: ffff88807acd8460 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #2: ffff888071910150 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:791 [inline]
 #2: ffff888071910150 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: ovl_workdir_create+0x159/0x9d0 fs/overlayfs/super.c:771
 #3: ffff8880761ec3b0 (&sbi->cp_rwsem){.+.+}-{3:3}, at: f2fs_down_read fs/f2fs/f2fs.h:2154 [inline]
 #3: ffff8880761ec3b0 (&sbi->cp_rwsem){.+.+}-{3:3}, at: f2fs_lock_op fs/f2fs/f2fs.h:2197 [inline]
 #3: ffff8880761ec3b0 (&sbi->cp_rwsem){.+.+}-{3:3}, at: f2fs_mkdir+0x221/0x520 fs/f2fs/namei.c:770
 #4: ffff8880719107c0 (&fi->i_xattr_sem){.+.+}-{3:3}, at: f2fs_down_read fs/f2fs/f2fs.h:2154 [inline]
 #4: ffff8880719107c0 (&fi->i_xattr_sem){.+.+}-{3:3}, at: f2fs_add_dentry+0x9b/0x1e0 fs/f2fs/dir.c:814

stack backtrace:
CPU: 1 PID: 3540 Comm: syz-executor166 Not tainted 6.1.42-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3098 [inline]
 check_prevs_add kernel/locking/lockdep.c:3217 [inline]
 validate_chain+0x1667/0x58e0 kernel/locking/lockdep.c:3832
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
 down_write+0x36/0x60 kernel/locking/rwsem.c:1573
 f2fs_down_write fs/f2fs/f2fs.h:2179 [inline]
 f2fs_add_inline_entry+0x3a4/0x760 fs/f2fs/inline.c:645
 f2fs_add_dentry+0xb6/0x1e0 fs/f2fs/dir.c:815
 f2fs_do_add_link+0x21a/0x340 fs/f2fs/dir.c:858
 f2fs_add_link fs/f2fs/f2fs.h:3530 [inline]
 f2fs_mkdir+0x2f1/0x520 fs/f2fs/namei.c:771
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4036
 ovl_do_mkdir fs/overlayfs/overlayfs.h:186 [inline]
 ovl_mkdir_real+0xcf/0x2c0 fs/overlayfs/dir.c:146
 ovl_workdir_create+0x449/0x9d0 fs/overlayfs/super.c:799
 ovl_make_workdir fs/overlayfs/super.c:1389 [inline]
 ovl_get_workdir+0x3b7/0x17b0 fs/overlayfs/super.c:1539
 ovl_fill_super+0x1b85/0x2a20 fs/overlayfs/super.c:2095
 mount_nodev+0x52/0xe0 fs/super.c:1469
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1553
 do_new_mount+0x28b/0xae0 fs/namespace.c:3040
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f6912cc27b9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc2c9753c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007f6912cc27b9
RDX: 00000000200001c0 RSI: 0000000020000180 RDI: 0000000000000000
RBP: 00007f6912d3a610 R08: 0000000020000300 R09: 0000000000000000