No, they do not. The code was released out of the kindness and as a
contribution to the community as a whole. It is still the property of
Samsung to do with what they please.
The Samsung code contains statements like 'Some of the source code in this
file came from "linux/fs/fat/misc.c"' and 'Some of the source code in this
file came from "linux/fs/fat/file.c","linux/fs/fat/inode.c" and
"linux/fs/fat/misc.c"' and 'Some of the source code in this file came from
"linux/fs/fat/fat.h"'
I myself haven't done a comparison of the Samsung source code and the
kernel source but I have read of others who have done so and found the
statements in the Samsung code to be true (i.e. that the Samsung code IS
using code from other kernel source files).
Therefore the Samsung code is a derived work of kernel code not written by
Samsung and they are required to comply with the terms of GPLv2 as applied
to misc.c, file.c, inode.c, fat.h and any other source files they may have
copied from.