If a manufacutere decides to use ANY software in his product, it's up to him/her to
A: test the software in the configuration he installs it in, on his hardware
B: fix bugs and provide patches/updates
This is irregardless of the provenance of the software. If its FOSS, there is at least the possiblity that bug fixes and updates will be provided for him/her by trhe community that wrote/supprts it, saving time and effort.
As was stated above, when you start making a profit from software, however it was sourced, the manufactureere should take responsibility for it, throughout its lifetime.