validateOutputPath() previously only resolved symlinks on the parent directory.
A symlink at /tmp/evil.png → /etc/crontab passed the parent check (parent is
/tmp, which is safe) but the write followed the symlink outside safe dirs.
Add lstatSync() check: if the target file exists and is a symlink, resolve
through it and verify the real target is within SAFE_DIRECTORIES. ENOENT
(file doesn't exist yet) falls through to the existing parent-dir check.
Closes#921
Co-Authored-By: Yunsu <Hybirdss@users.noreply.github.com>
Garry Tan
4b9fb4a3db