Re: Problem with ISO9660 and files stored on multiple extents

[Carlo Caione]

On Thu, Feb 16, 2017 at 4:54 PM, Vladimir 'phcoder' Serbinenko
<address@hidden> wrote:
>
>
> On Thu, Feb 16, 2017, 14:14 Carlo Caione <address@hidden> wrote:
>>
>> On Thu, Feb 16, 2017 at 2:09 PM, Vladimir 'phcoder' Serbinenko
>> <address@hidden> wrote:
>> >
>> >
>> > On Thu, Feb 16, 2017, 14:04 Carlo Caione <address@hidden> wrote:
>> >>
>> >> On Thu, Feb 16, 2017 at 12:37 PM, Carlo Caione <address@hidden>
>> >> wrote:
>> >> > On Thu, Feb 16, 2017 at 12:32 PM, Thomas Schmitt <address@hidden>
>> >> > wrote:
>> >> >> Hi,
>> >> >>
>> >> >> Carlo Caione wrote:
>> >> >>> > I think that the problem
>> >> >>> > here is that endless.squash has been stored in two extents in the
>> >> >>> > ISO9660 and GRUB doesn't deal fine with that (also according to
>> >> >>> > this
>> >> >>> > comment
>> >> >>> >
>> >> >>> >
>> >> >>> > http://git.savannah.gnu.org/cgit/grub.git/tree/grub-core/fs/iso9660.c#n960
>> >> >>
>> >> >> Andrei Borzenkov wrote:
>> >> >>> This comment could be stale and misleading.
>> >> >>
>> >> >> The code of read_node() in iso9660.c looks ready for multi-extent
>> >> >> (aka
>> >> >> ISO
>> >> >> level 3).
>> >> >>
>> >> >> I have a very densely compressed test ISO for large file support
>> >> >>    http://scdbackup.webframe.org/large.iso.bz2
>> >> >> which bunzip2 inflates from 4.5 KiB to 4+ GiB.
>> >> >
>> >> > Yeah, I made some more tests and apparently the problem is not in the
>> >> > ISO9660 module but in the SQUASH4 module.
>> >> > To be perfectly honest I have already a patch that solves my problem
>> >> > but I'm having a hard time to understand WHY it solves the issue
>> >> > since
>> >> > I'm still not really familiar with squashfs (I casually found it
>> >> > during my debugging).
>> >> > Of course probably it is only masking a problem somewhere else. Still
>> >> > digging.
>> >> >
>> >> > diff --git a/grub-core/fs/squash4.c b/grub-core/fs/squash4.c
>> >> > index b97b344..4fef813 100644
>> >> > --- a/grub-core/fs/squash4.c
>> >> > +++ b/grub-core/fs/squash4.c
>> >> > @@ -895,7 +895,7 @@ grub_squash_read_data (struct grub_squash_data
>> >> > *data,
>> >> >        break;
>> >> >      }
>> >> >
>> >> > -  if (fragment == 0xffffffff)
>> >> > +  if (fragment == 0xffffffff || fragment == 0)
>> >> >      return direct_read (data, ino, off, buf, len);
>> >> >
>> >> >    err = read_chunk (data, &frag, sizeof (frag),
>> >>
>> >> Hey Vladimir,
>> >> Any idea about this?
>> >
>> > How big is the file in question? What is the squash tools version?
>>
>> The squash image is 4564504576
>
> I mean the size of file you try to access

In the squashfs image there is one single file of size 11470000128

-- 
Carlo Caione  |  +39.340.80.30.096  |  Endless