Re: [PATCH] hfsplus: fix segfault when deleting all attrs of a file

["Ernesto A. Fernández" <ernesto.mnd.fernandez@gmail.com>]

On Sat, Oct 07, 2017 at 04:25:22AM +0000, Hin-Tak Leung wrote:
> 
> --------------------------------------------
> On Sat, 7/10/17, Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com> wrote:
>  
> > A segmentation fault can be triggered by setting many xattrs
> > to a file
> > and then deleting it. The number must be high enough for
> > more than one
> > b-tree node to be needed for storage.
> 
> Sounds like it is easily/reliably reproducible - do you have an estimate/recipe of how many xattrs minimum to trigger this problem, to test and verify this fix?

I did not give a number because it depends on the size of the xattrs, and I
imagine the bnode size as well, though I only tested it with the default
mkfs options. Maybe I should have shared the script I used instead:

touch test.file
i=1
while [ $i -le 250 ]; do
  setfattr -n user.$i test.file
  ((++i))
done
rm test.file

Of course, if you set a value to the xattrs you will need fewer.

> Thanks a lot for the work!

And thank you for your attention.

> Hin-Tak
> 
>  

Ernest