fsck.ext4 -n exited with status code 4
e2fsck 1.47.0 (5-Feb-2023)
Bad required extra isize in superblock (65312).  Fix? no

Bad desired extra isize in superblock (255).  Fix? no

syzkaller contains a file system with errors, check forced.
Pass 1: Checking inodes, blocks, and sizes
Inode 13 logical block 0 (physical block 85) violates cluster allocation rules.
Will fix in pass 1B.
Inode 13 logical block 1 (physical block 86) violates cluster allocation rules.
Will fix in pass 1B.

Running additional passes to resolve blocks claimed by more than one inode...
Pass 1B: Rescanning for multiply-claimed blocks
Multiply-claimed block(s) in inode 13: 85--86
Pass 1C: Scanning directories for inodes with multiply-claimed blocks
Pass 1D: Reconciling multiply-claimed blocks
(There are 1 inodes containing multiply-claimed blocks.)

File /file0/file0 (inode #13, mod time Tue Nov 22 15:59:47 2022) 
  has 1 multiply-claimed block(s), shared with 0 file(s):
Clone multiply-claimed blocks? no

Delete file? no

Pass 2: Checking directory structure
Entry '' in /lost+found (11) has invalid inode #: 3.
Clear? no

Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Free blocks count wrong for group #0 (1305, counted=25).
Fix? no

Free inodes count wrong for group #0 (1295, counted=15).
Fix? no

Directories count wrong for group #0 (0, counted=3).
Fix? no

Padding at end of inode bitmap is not set. Fix? no


syzkaller: ********** WARNING: Filesystem still has errors **********

syzkaller: 17/32 files (0.0% non-contiguous), 112/512 blocks