fsck.ext4 -n exited with status code 4
e2fsck 1.47.0 (5-Feb-2023)
syzkaller contains a file system with errors, check forced.
Pass 1: Checking inodes, blocks, and sizes
Bad block inode has illegal block(s).  Clear? no

Illegal block #1 (67108864) in bad block inode.  IGNORED.
Inode 13 missing EXTENT_FL, but is in extents format
Fix? no

Inode 13 has illegal block(s).  Clear? no

Illegal block #0 (127754) in inode 13.  IGNORED.
Inode 13, i_size is 1050, should be 12288.  Fix? no

Inode 13, i_blocks is 64, should be 192.  Fix? no

Inode 13 on bigalloc filesystem cannot be block mapped.  Fix? no


Running additional passes to resolve blocks claimed by more than one inode...
Pass 1B: Rescanning for multiply-claimed blocks
Illegal block number passed to ext2fs_test_block_bitmap #4194304 for multiply claimed block map
Illegal block number passed to ext2fs_test_block_bitmap #7984 for multiply claimed block map
Multiply-claimed block(s) in inode 13: 4 1
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 15:59:50 2022) 
  has 1 multiply-claimed block(s), shared with 1 file(s):
	<filesystem metadata>
Clone multiply-claimed blocks? no

Delete file? no

Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Free blocks count wrong for group #0 (150994969, counted=25).
Fix? no


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

syzkaller: 17/32 files (5.9% non-contiguous), 112/512 blocks