[PATCH] get_interfaces() return early causes segfault in winbind

[Ralph Böhme]

On Thu, Oct 25, 2018 at 09:18:53AM -0600, David Mulder via samba-technical wrote:
>Regression caused by da68a1b2f417ec82ea4ed3e7a4d867cef8ca8f93.
>
>If we return early, be sure to point pifaces to the returned ifaces if
>we have 1 return. Otherwise winbind segfaults in load_interfaces() if
>there is only 1 interface, because we say there is 1 interface, but
>ifaces is NULL (load_interfaces() tries to smb_memdup NULL of iface size 1).
>
>Seen on a machine where dhcp was slow to return, so winbind crashed on
>started due to lo being the only interface available on start.
>
>Please review and push if ok!

lgtm.

Can I get a second team member review?

Also, is this present in 4.9? If so, we need a bug for the bugnumber for the 
backports. :)

-slow

-- 
Ralph Boehme, Samba Team       https://samba.org/
Samba Developer, SerNet GmbH   https://sernet.de/en/samba/
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