Need to null terminate environment.  Found by inspection while looking for
similar problems to platform uevent bug
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
        err = add_uevent_var(envp, num_envp, &cur_index, buffer, buffer_size,
                        &cur_len, "W1_SLAVE_ID=%024LX",
                        (unsigned long long)sl->reg_num.id);
+       envp[cur_index] = NULL;
        if (err)
                return err;