Saving documents with broken zip streams (Re: minutes of ESC call ...)

[Luboš Luňák]

On Friday 07 of June 2019, Wols Lists wrote:
> On 07/06/19 10:07, Luboš Luňák wrote:
> >> For what its worth those sample documents are not "realworld" user
> >> documents, but the output of fuzzing engines so any non-catastrophic
> >> outcome is acceptable IMO
> >
> >  I have avoided the assert with https://gerrit.libreoffice.org/#/c/73646/
> > . Given that it's (hopefully) very unlikely to find real documents with
> > broken zip internals, I find that good enough.
>
> Bear in mind I don't know the background to this ...
>
> My immediate reaction was "we can't refuse to let the user save their
> document, so could we disable 'save' and do a 'save as'?".

 That doesn't make a difference here. The code can't save such a broken 
document, period. Regardless of where it is being saved to.

> As for unlikely to find broken documents, it's too long ago for me to
> remember the details, but I remember salvaging a broken calc document by
> unzipping it and recovering the data portion. So real-world broken
> documents do happen (although I think in this case it was broken such
> that LO refused to open it ...)

 Manually unzipping and zipping back properly would work here too. Or you can 
improve the saving code to cope with such problems somehow, feel free to.

-- 
 Luboš Luňák
 l.lunak at collabora.com