Error. Unable to extract the compressed Linux file system.

[Tipitopitapi]

Describe the bug

I have build a customized Mint ISO, wich I successfully created (v1), and then I customized this image again successfully to an new further customized image (v2). So I could read in v1 and create v2. Both are bootable. Now I wanted to customize v1 again to create a new v2, but this time the filesystem could not be extracted.

A clear and concise description of what the bug is.

The same ISO I could read in once, but now not anymore - but it is the same ISO image.... (deleted also all files in the Cubic session folder, before new session)

OS Information (please complete the following information):

• Ubuntu 25.10

Cubic Information (please complete the following information):

• Cubic Version: newest
• ISO Customizing: newest Mint (cinnamom)

Cubic Log:

The message is.........................FATAL ERROR: File system corrupted -
                                            xattr_ids is 0 in xattr table     
the exception is....................... End Of File (EOF). Exception style  
                                            platform. <pexpect.pty_spawn.spawn  
                                            object at 0x74901d5860d0> command:  
                                            /usr/bin/pkexec args:               
                                            [b'/usr/bin/pkexec',                
                                            b'/usr/share/cubic/commands/extract-
                                            root', b'/home/userxyz/Cubic/source-   
                                            disk/casper/filesystem.squashfs',   
                                            b'/home/nils/Cubic/custom-root']    
                                            buffer (last 100 chars): '' before  
                                            (last 100 chars): 'FATAL ERROR: File
                                            system corrupted - xattr_ids is 0 in
                                            xattr table\r\n' after: <class      
                                            'pexpect.exceptions.EOF'> match:    
                                            None match_index: None exitstatus:  
                                            None flag_eof: True pid: 3881       
                                            child_fd: 197 closed: False timeout:
                                            300 delimiter: <class               
                                            'pexpect.exceptions.EOF'> logfile:  
                                            None logfile_read: None             
                                            logfile_send: None maxread: 2000    
                                            ignorecase: False searchwindowsize: 
                                            None delaybeforesend: 0.05          
                                            delayafterclose: 0.1                
                                            delayafterterminate: 0.1 searcher:  
                                            searcher_re:     0: re.compile('[0- 
                                            9]{1,3}(\\.[0-9]{2}){0,1}%')        
                                            message: FATAL ERROR: File system   
                                            corrupted - xattr_ids is 0 in xattr 
                                            table                               
  • The trace back is...................... Traceback (most recent call last):  
                                            File "/usr/share/cubic/cubic/utiliti
                                            es/progressor.py", line 413, in     
                                            process_command     if not done:    
                                            raise exception                     
                                            ^^^^^^^^^^^^^^^   File "/usr/share/c
                                            ubic/cubic/utilities/progressor.py",
                                            line 408, in process_command        
                                            process.expect(PERCENT_PATTERN)     
                                            ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^     
                                            File "/usr/lib/python3/dist-        
                                            packages/pexpect/spawnbase.py", line
                                            354, in expect     return self.expec
                                            t_list(compiled_pattern_list,       
                                            ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^
                                            ^^^             timeout,            
                                            searchwindowsize, async_)           
                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^  
                                            File "/usr/lib/python3/dist-        
                                            packages/pexpect/spawnbase.py", line
                                            383, in expect_list     return      
                                            exp.expect_loop(timeout)            
                                            ~~~~~~~~~~~~~~~^^^^^^^^^   File     
                                            "/usr/lib/python3/dist-             
                                            packages/pexpect/expect.py", line   
                                            179, in expect_loop     return      
                                            self.eof(e)            ~~~~~~~~^^^  
                                            File "/usr/lib/python3/dist-        
                                            packages/pexpect/expect.py", line   
                                            122, in eof     raise exc           
                                            pexpect.exceptions.EOF: End Of File 
                                            (EOF). Exception style platform.    
                                            <pexpect.pty_spawn.spawn object at  
                                            0x74901d5860d0> command:            
                                            /usr/bin/pkexec args:               
                                            [b'/usr/bin/pkexec',                
                                            b'/usr/share/cubic/commands/extract-
                                            root', b'/home/userxyz/Cubic/source-   
                                            disk/casper/filesystem.squashfs',   
                                            b'/home/userxyz/Cubic/custom-root']    
                                            buffer (last 100 chars): '' before  
                                            (last 100 chars): 'FATAL ERROR: File
                                            system corrupted - xattr_ids is 0 in
                                            xattr table\r\n' after: <class      
                                            'pexpect.exceptions.EOF'> match:    
                                            None match_index: None exitstatus:  
                                            None flag_eof: True pid: 3881       
                                            child_fd: 197 closed: False timeout:
                                            300 delimiter: <class               
                                            'pexpect.exceptions.EOF'> logfile:  
                                            None logfile_read: None             
                                            logfile_send: None maxread: 2000    
                                            ignorecase: False searchwindowsize: 
                                            None delaybeforesend: 0.05          
                                            delayafterclose: 0.1                
                                            delayafterterminate: 0.1 searcher:  
                                            searcher_re:     0: re.compile('[0- 
                                            9]{1,3}(\\.[0-9]{2}){0,1}%')        
  • Stopped process thread id.............. 128161860769472          
  • Raise the exception to thread id....... 128162176423616                     
  • Do not propagate exception............. _PyErr_SetObject: exception EOF("End
                                            Of File (EOF). Exception style      
                                            platform.\n<pexpect.pty_spawn.spawn 
                                            object at 0x74901d5860d0>\ncommand: 
                                            /usr/bin/pkexec\nargs:              
                                            [b'/usr/bin/pkexec',                
                                            b'/usr/share/cubic/commands/extract-
                                            root', b'/home/userxyz/Cubic/source-   
                                            disk/casper/filesystem.squashfs',   
                                            b'/home/userxyz/Cubic/custom-          
                                            root']\nbuffer (last 100 chars):    
                                            ''\nbefore (last 100 chars): 'FATAL 
                                            ERROR: File system corrupted -      
                                            xattr_ids is 0 in xattr             
                                            table\\r\\n'\nafter: <class         
                                            'pexpect.exceptions.EOF'>\nmatch:   
                                            None\nmatch_index: None\nexitstatus:
                                            None\nflag_eof: True\npid:          
                                            3881\nchild_fd: 197\nclosed:        
                                            False\ntimeout: 300\ndelimiter:     
                                            <class                              
                                            'pexpect.exceptions.EOF'>\nlogfile: 
                                            None\nlogfile_read:                 
                                            None\nlogfile_send: None\nmaxread:  
                                            2000\nignorecase:                   
                                            False\nsearchwindowsize:            
                                            None\ndelaybeforesend:              
                                            0.05\ndelayafterclose:              
                                            0.1\ndelayafterterminate:           
                                            0.1\nsearcher: searcher_re:\n    0: 
                                            re.compile('[0-9]{1,3}(\\\\.[0-     
                                            9]{2}){0,1}%')\nmessage: FATAL      
                                            ERROR: File system corrupted -      
                                            xattr_ids is 0 in xattr table") is  
                                            not a BaseException subclass     

Screenshots

[PJ-Singh-001]

Are you still experiencing this bug?

[Tipitopitapi]

Yes all the time I try. As I said, I once was able to extract exact from this image and biuld an new image without a problem.

[Tipitopitapi]

Do you have any updates?

[PJ-Singh-001]

I was not able to recreate this problem.
I followed your sequence of steps, and I also did an extra check (see test # 4 below).

I tested Cubic using Linux Mint 22.3 XFCE downloaded from here.

• After generating each ISO, I tested the generated ISO using Cubic's Test page, and I ensured the version and changes I made were present.

• Each test was a new Cubic project. (I assume you had deleted your previous Cubic projects, which is why you started with the generated ISO (such as V1) instead of simply opening up your existing Cubic project (such as V1) to continue working on it).

Here are the four tests:

1. Starting with linuxmint-22.3-xfce-64bit.iso, I created linuxmint-22.3.0-2026.06v1-xfce-64bit.iso (V1).
2. Starting with linuxmint-22.3-xfce-64bit.iso, I created linuxmint-22.3.0-2026.06v3-2026.06v1-xfce-64bit.iso (V2).
3. Going back to linuxmint-22.3.0-2026.06v1-xfce-64bit.iso (V1), I created linuxmint-22.3.0-2026.06v2-2026.06v1-xfce-64bit.iso (V3).
4. Just to double check that repeatedly customizing ISOs created using Cubic produces working ISOs, I then used linuxmint-22.3.0-2026.06v2-2026.06v1-xfce-64bit.iso (V3) to create linuxmint-22.3.0-2026.06.06v4-2026.06v3-2026.06v1-xfce-64bit.iso (V4).

Here is the provenance of the customized ISOs...

linuxmint-22.3-xfce-64bit.iso (Official ISO)
├── linuxmint-22.3.0-2026.06v1-xfce-64bit.iso (V1)
│   └── linuxmint-22.3.0-2026.06v2-2026.06v1-xfce-64bit.iso (V3)
│       └── linuxmint-22.3.0-2026.06.06v4-2026.06v3-2026.06v1-xfce-64bit.iso (V4)
└── linuxmint-22.3.0-2026.06v3-2026.06v1-xfce-64bit.iso (V2)

Here is a screenshot of test # 4 in Cubic's Project page, demonstrating that ISOs generated using Cubic can be used to create subsequent custom ISOs.

Here is a screenshot of test # 4, showing the working customized OS.

[PJ-Singh-001]

Based on these tests, I wonder if your V1 ISO is simply corrupted.

You may have developed some bad bytes on disk after the first time you used V1 to create V2.

The message in the log file implies this:

The message is.........................FATAL ERROR: File system corrupted -
                                            xattr_ids is 0 in xattr table 

xattrs are name-value pairs associated with files and directories.

Try recreating the four tests I conducted and report back if you are still experiencing the same issue.

[Tipitopitapi]

The ISOs both were corrupted. Built a new one an updated that in a second session (with clean project folder), works as expected. Thanks!

[PJ-Singh-001]

I appreciate you updating me on the resolution.

I'm glad it's working for you.

Good luck with your project -- I will close this issue.

---

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