/usr/include/sofa/component/linearsolver/ is in libsofa1-dev 1.0~beta4-10ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/sofa/component/linearsolver/BTDLinearSolver.h
/usr/include/sofa/component/linearsolver/BlockJacobiPreconditioner.h
/usr/include/sofa/component/linearsolver/CGLinearSolver.h
/usr/include/sofa/component/linearsolver/CholeskySolver.h
/usr/include/sofa/component/linearsolver/CompressedRowSparseMatrix.h
/usr/include/sofa/component/linearsolver/FullMatrix.h
/usr/include/sofa/component/linearsolver/FullVector.h
/usr/include/sofa/component/linearsolver/JacobiPreconditioner.h
/usr/include/sofa/component/linearsolver/LULinearSolver.h
/usr/include/sofa/component/linearsolver/LapackOperations.h
/usr/include/sofa/component/linearsolver/MKLMatrix.h
/usr/include/sofa/component/linearsolver/MKLVector.h
/usr/include/sofa/component/linearsolver/MatrixLinearSolver.h
/usr/include/sofa/component/linearsolver/NewMatMatrix.h
/usr/include/sofa/component/linearsolver/NewMatVector.h
/usr/include/sofa/component/linearsolver/PCGLinearSolver.h
/usr/include/sofa/component/linearsolver/SSORPreconditioner.h
/usr/include/sofa/component/linearsolver/SparseCholeskySolver.h
/usr/include/sofa/component/linearsolver/SparseLDLSolver.h
/usr/include/sofa/component/linearsolver/SparseLUSolver.h
/usr/include/sofa/component/linearsolver/SparseMatrix.h
/usr/include/sofa/component/linearsolver/SparseTAUCSSolver.h
/usr/include/sofa/component/linearsolver/initLinearSolver.h