Re: FreeBSD core dumps when wrapping big files!

Joey Mukherjee wrote:

>> I have no idea if this is coincidence, but 2^25 == 67108864.
>
> Winner!
>
> As guessed, using "dd if=/dev/random of=filename bs=1  
> count=67108864" to create a file, it crashes the creation.  If I  
> use 67108863, it works fine.
[...]
>> Out of curiosity, what are the resultant sizes of the starpack?
>
> This seems to be random everytime.  After this latest crash, the  
> file size of setup is 1913111.  I seen as small as 380 or so bytes  
> to huge.  When it succeeds at the 67108863, the file size is  
> 73079792.  This has my other junk in it as well, though.

The input size seems to trigger this.

> To answer some other questions:
>
> 1) Adding -nocomp makes no difference.  Either way it crashes.
> 2) If I wrap only the big file, it crashes.
> 3) If I wrap the big file on Linux, I *CAN* unwrap it on FreeBSD.
>
> The only thing I did not do that was asked, was if it was text or  
> not.  I am pretty convinced it's size oriented so I didn't bother.
>
> Finally, my last attachment is the long traceback with a symbols  
> enabled tclkit-cli.

That's interesting - so sdx wrap breaks without any Mk4tcl/mk4vfs in  
there.  I'm continuing to suspect tclvfs... if the stat buffer has a  
64-bit item while the rest of the system expects 32, or simply if  
wrong struct sizes put the wrong data in the wrong memory bytes, then  
yes a 2^25 bit change could well trigger it (say that particular byte  
is always supposed to be 0 or 1).

I'll go through the stack trace a bit more.  Nothing jumps out yet.

-jcw