Virally licensed code in FreeBSD kernel

Philipp Wuensche cryx-freebsd at
Sat Apr 14 16:55:42 UTC 2007

Brett Glass wrote:
> There is a huge problem in that the CDDL is "viral." It "infects"
> products with which it is combined. You can read the text of the
> CDDL at
> Section 3.1 of the CDDL is the portion which is essentially equivalent
> to the GPL. 

It basically states that you have to provide the source code for the
stuff that already is under CDDL license if you distribute binaries and
you have to keep the CDDL license for all the code that is already under
CDDL license.

I'm no lawyer but I don't see where this is as viral as GPL. The viral
part is limited to the already CDDL licensed source.

You create a binary from two source files.

1. one BSD one CDDL. If you distribute this binary, you have to provide
the CDDL part (and all modifications to it) as source under CDDL
license. You are not required to provide the source of the BSD part.

2. one BSD one GPL. If you distribute the binary, you have to provide
the source of both files (and I think you even have to do that under
GPL). That is because GPL requires that all work descended from it falls
under GPL too and all binaries that include GPL code require the
distribution of the source. Thats why it is called viral.

So CDDL does not require to license add-ons under CDDL, GPL does. In
this terms, FreeBSD is basically an add-on to the ZFS module ;-).


More information about the freebsd-questions mailing list