Re: [Libguestfs] [xml] Why does libxml2 limit port numbers to 999, 999, 999?
On Sat, Oct 17, 2020 at 06:32:18PM +0200, Nick Wellnhofer wrote:
On Oct 17, 2020, at 12:24 , Richard W.M. Jones via xml
<xml(a)gnome.org> wrote:
> It seems like libxml2 chose to do this for convenience rather than
> correctness.
Yes, this is an arbitrary limit introduced to avoid integer overflow.
> I think it should accept port numbers at least up to
> signed int (the type used to store port numbers), and give an error if
> the port number overflows.
This is fixed now:
https://gitlab.gnome.org/GNOME/libxml2/-/commit/b46016b8705b041c0678dd45e...
Oh that's great thanks. Can confirm it works for me (up to INT_MAX).
> Also could the uri->port field be changed to unsigned int
without
> breaking ABI?
It’s a public struct member, so strictly speaking, no. But the risk
to break stuff seems low.
This would allow us to go to 2^32-1 which is the full range of
port numbers for AF_VSOCK.
** Stefano ** Do you think this is worth it for the vsock protocol?
I'm not sure how often huge port numbers are used - I only hit this
bug because I was choosing random port numbers in a test case.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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