svn commit: r338571 - in head/sys: netinet netinet6

[Mark Johnston]

On Tue, Sep 11, 2018 at 12:13:05PM +0200, Alexander Leidinger wrote:
> 
> Quoting Mark Johnston <markj at freebsd.org> (from Mon, 10 Sep 2018  
> 19:00:29 +0000 (UTC)):
> 
> > Author: markj
> > Date: Mon Sep 10 19:00:29 2018
> > New Revision: 338571
> > URL: https://svnweb.freebsd.org/changeset/base/338571
> >
> > Log:
> >   Fix synchronization of LB group access.
> >
> >   Lookups are protected by an epoch section, so the LB group linkage must
> >   be a CK_LIST rather than a plain LIST.  Furthermore, we were not
> >   deferring LB group frees, so in_pcbremlbgrouphash() could race with
> >   readers and cause a use-after-free.
> 
> Is this related to PR 230950?
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=230950

Probably not.  SO_REUSEPORT_LB is new and not many applications use it
yet; nginx is the sole consumer that I've found.  The issues fixed in
this commit were found by code inspection.