https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104161
--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-11 branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:e20b1c711f70d8d251d45694c50c02e66a4d9f7b commit r11-11036-ge20b1c711f70d8d251d45694c50c02e66a4d9f7b Author: Jonathan Wakely <jwak...@redhat.com> Date: Sun Jan 23 21:45:16 2022 +0000 libstdc++: Avoid symlink race in filesystem::remove_all [PR104161] This adds a new internal flag to the filesystem::directory_iterator constructor that makes it fail if the path is a symlink that resolves to a directory. This prevents filesystem::remove_all from following a symlink to a directory, rather than deleting the symlink itself. We can also use that new flag in recursive_directory_iterator to ensure that we don't follow symlinks if the follow_directory_symlink option is not set. This also moves an error check in filesystem::remove_all after the while loop, so that errors from the directory_iterator constructor are reproted, instead of continuing to the filesystem::remove call below. libstdc++-v3/ChangeLog: PR libstdc++/104161 * acinclude.m4 (GLIBCXX_CHECK_FILESYSTEM_DEPS): Check for fdopendir. * config.h.in: Regenerate. * configure: Regenerate. * src/c++17/fs_dir.cc (_Dir): Add nofollow flag to constructor and pass it to base class constructor. (directory_iterator): Pass nofollow flag to _Dir constructor. (fs::recursive_directory_iterator::increment): Likewise. * src/c++17/fs_ops.cc (do_remove_all): Use nofollow option for directory_iterator constructor. Move error check outside loop. * src/filesystem/dir-common.h (_Dir_base): Add nofollow flag to constructor and when it's set use ::open with O_NOFOLLOW and O_DIRECTORY. * src/filesystem/dir.cc (_Dir): Add nofollow flag to constructor and pass it to base class constructor. (directory_iterator): Pass nofollow flag to _Dir constructor. (fs::recursive_directory_iterator::increment): Likewise. * src/filesystem/ops.cc (remove_all): Use nofollow option for directory_iterator constructor. Move error check outside loop. (cherry picked from commit c8bd4dc8212e43b2f9af08b80df97f90cdb0df4f)
