/usr/share/polymake/apps/fan/src/ is in polymake-common 3.2r2-3.
This file is owned by root:root, with mode 0o755.
..
/usr/share/polymake/apps/fan/src/all_cones_symmetry.cc
/usr/share/polymake/apps/fan/src/check_fan.cc
/usr/share/polymake/apps/fan/src/common_refinement.cc
/usr/share/polymake/apps/fan/src/face_fan.cc
/usr/share/polymake/apps/fan/src/gkz_computation.cc
/usr/share/polymake/apps/fan/src/graph_associahedron_fan.cc
/usr/share/polymake/apps/fan/src/hasse_diagram.cc
/usr/share/polymake/apps/fan/src/hyperplane_arrangement.cc
/usr/share/polymake/apps/fan/src/k_skeleton.cc
/usr/share/polymake/apps/fan/src/metric_tight_span.cc
/usr/share/polymake/apps/fan/src/mixed_subdivision.cc
/usr/share/polymake/apps/fan/src/nested_sets.cc
/usr/share/polymake/apps/fan/src/normal_fan.cc
/usr/share/polymake/apps/fan/src/planar_net.cc
/usr/share/polymake/apps/fan/src/product.cc
/usr/share/polymake/apps/fan/src/pseudo_regularity.cc
/usr/share/polymake/apps/fan/src/regularity.cc
/usr/share/polymake/apps/fan/src/remove_redundancies.cc
/usr/share/polymake/apps/fan/src/remove_redundant_cones.cc
/usr/share/polymake/apps/fan/src/tight_span.cc
/usr/share/polymake/apps/fan/src/tiling_quotient.cc