SquashFs - Error on mount

Jul 12, 2012 at 9:58 AM
Edited Jul 12, 2012 at 10:04 AM

Hello again,

I have a strange Problem, I successfully created "Packages" for a embedded Linux system a while ago, but now if the package is mounted, mount always returns "SQUASHFS error: unable to read id index table". I can't remember touching the code, but there were some system updates on the embedded system.

Anyone has a hint ?

I'm doing nothing special here:


            SquashFileSystemBuilder b = new SquashFileSystemBuilder();
            b.DefaultFilePermissions = UnixFilePermissions.OwnerRead
                | UnixFilePermissions.OwnerWrite
                | UnixFilePermissions.GroupRead
                | UnixFilePermissions.GroupWrite
                | UnixFilePermissions.OwnerExecute
                | UnixFilePermissions.GroupExecute
                | UnixFilePermissions.OthersExecute
                | UnixFilePermissions.OthersAll
                | UnixFilePermissions.GroupAll;

            string tmpPxmlDoc = Path.GetTempFileName();

            Files.Add(new projectFile() { SourceFilePath = tmpPxmlDoc, DestinationFilePath = "pxml.xml", Type = pndFileTypes.pmxlfile });

            foreach (projectFile pf in Files)
                b.AddFile(pf.DestinationFilePath, pf.SourceFilePath);

            string tmpFileName = Path.GetTempFileName();



I'm not absolutely sure, but I think that I was able to open the created images with 7zip back then, this also doesn't seem to work anymore.

Jul 29, 2012 at 1:20 PM


I've just tried out a simple case, somewhat like yours - and the filesystem seems OK.  (using unsquashfs v4.2 on Ubuntu)

Can you provide a self-contained example that fails, please - then I can take a look in more depth.




Jul 31, 2012 at 6:14 AM
Edited Jul 31, 2012 at 6:17 AM


thanks for answering. I'm currently not able to provide a special sample. There is a sample online, but as there are no possibilities to attach something in this thread or to a message - I could only provide you with a link to that file. But this would require you to register in a forum (if you still like to get it: the file is attached to post #29 in this thread http://boards.openpandora.org/index.php?/topic/7725-package-dosbox-games-as-pnds/page__st__20#entry141408 , the file is called "dosbox.squarez.pnd").

thanks again

Aug 14, 2012 at 7:24 AM

Me again,

I had a brief conversation with the main OS developer of the embedded system and as it seems the error is related to moving to the current 3.2 linux kernel. He wrote that there were several commits between Kernel 2.6 and 3.2 that making file format checking much stricter (see http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=history;f=fs/squashfs;hb=HEAD).

If you still need/want a testsample I would be happy to provide one - just give me a hint on how the get the sample to you

Aug 15, 2012 at 11:23 AM

Thanks - that's really helpful.  I can see at least one place where DiscUtils writes structures in a different order, so could cause problems.

I think I have enough to work on this for now.




Aug 16, 2012 at 8:52 PM
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