can't access patch file in review directory

During checkSyntax(), I'm getting:

file_get_contents(sites/default/files/review/syntax.patch) [function.file-get-contents]: failed to open stream: No such file or directory in /var/www/sites/all/modules/project_issue_file_review/client/review/vcs/cvs.inc on line 27.
chdir() [function.chdir]: No such file or directory (errno 2) in /var/www/sites/all/modules/project_issue_file_review/client/review/pifr_client_review.inc on line 297.

Then during review.install(), I get:

copy(sites/default/files/checkout/sites/default/default.settings.php) [function.copy]: failed to open stream: No such file or directory in /var/www/sites/all/modules/project_issue_file_review/client/review/pifr_client_review.inc on line 314.
PIFRClientReview::require_once(sites/all/modules/project_issue_file_review/client/review/browser.inc) [pifrclientreview.require-once]: failed to open stream: No such file or directory in /var/www/sites/all/modules/project_issue_file_review/client/review/pifr_client_review.inc on line 316.

I've never gotten these before, so I don't know if they might be related to what updates happened last night. The strange thing is that when I go look in the review directory, there is a readable syntax.patch file there, so maybe the relative working directory got messed up somewhere? There's a fatal error somewhere during review.install(), which I haven't run a backtrace on yet, but it prevents PIFR from moving on to review.runTests().