1465072 - Force marionette::get_free_port() to use IPv4

Status: RESOLVED FIXED

(Testing :: geckodriver, enhancement)

Description

[Andreas Tolfsen ❲:ato❳]

The marionette::get_free_port() function still uses localhost to
resolve a free port.  As a follow up to
https://bugzilla.mozilla.org/show_bug.cgi?id=1462040 we should
ensure it also consistently uses IPv4, otherwise we may end up
finding a free port on the IPv6 stack that Firefox cannot bind to.

Comment 1

[Andreas Tolfsen ❲:ato❳]

Attachment: Bug 1465072 - Force IPv4 for marionette::get_free_port().

As part of bug 1462040, geckodriver was made to use the IPv4 stack
when connecting to Marionette in Firefox.  However, the helper
function for finding an atomic free port still uses localhost,
which on some systems may prefer the IPv6 stack.

To ensure that the free port is found on the correct IP stack, this
patch changes marionette::get_free_port() to use the DEFAULT_HOST
constant that is already used for establishing the connection.

Review commit: https://reviewboard.mozilla.org/r/247552/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/247552/

Comment 2

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Comment on attachment 8981440 [details]
Bug 1465072 - Force IPv4 for marionette::get_free_port().

https://reviewboard.mozilla.org/r/247552/#review253602

::: testing/geckodriver/src/marionette.rs:1323
(Diff revision 1)
>          }
>      }
>  }
>  
>  fn get_free_port() -> IoResult<u16> {
> -    TcpListener::bind(&("localhost", 0))
> +    TcpListener::bind(&(DEFAULT_HOST, 0))

Hurray for using constants. Thanks for catching that!

Comment 3

[Andreas Tolfsen ❲:ato❳]

Comment on attachment 8981440 [details]
Bug 1465072 - Force IPv4 for marionette::get_free_port().

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/247552/diff/1-2/

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4ad07f3127fe
Force IPv4 for marionette::get_free_port(). r=whimboo

Comment 5

[Noemi Erli[:noemi_erli]]

https://hg.mozilla.org/mozilla-central/rev/4ad07f3127fe