commit 8321cf25 upstream.

There is otherwise a risk of a possible null pointer dereference.

Was largely found by using a static code analysis program called cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>