Handle excessively long paths

conservancy/tests.py

@@ -55,3 +55,9 @@ def test_path_traversal_404s(rf):
     request = rf.get('/about/../../../conservancy-website.sqlite3')
     with pytest.raises(Http404):
         views.content(request)
+
+
+def test_long_path_404s(rf):
+    request = rf.get('x' * 1000)
+    with pytest.raises(Http404):
+        views.content(request)

conservancy/views.py

@@ -52,11 +52,15 @@ def content(request, *args, **kwargs):
         path += 'index.html'
     full_path = (base_path / path).resolve()
     safe_from_path_traversal = full_path.is_relative_to(base_path)
+    try:
         if full_path.is_dir():
             # Should have been accessed with a trailing slash.
             return HttpResponseRedirect(request.path + '/')
         elif not full_path.exists() or not safe_from_path_traversal:
             raise Http404()
+    except OSError:
+        # eg. path is too long
+        raise Http404()
     is_template = mimetypes.guess_type(full_path)[0] == 'text/html'
     if not is_template:
         return FileResponse(open(full_path, 'rb'))