Permissions, flags and attributes
Change uid and gid
usermod -u 2005 foo
groupmod -g 3000 foo
find / -group 2000 -exec chgrp -h foo {} \;
find / -user 1005 -exec chown -h foo {} \;
usermod -g <NEWGID> <LOGIN>
End-to-end file access without read directory
chmod 711 <folder name>
Sticky Bit
chmod +t <folder or file name>
Restore execute bit to chmod tool
setfacl -m u::rwx,g::rx,o::x /usr/bin/chmod
/usr/lib64/ld-linux-x86-64.so.2 /usr/bin/chmod +x /usr/bin/chmod
cp --attributes-only /usr/bin/ls ./new_chmod; cat /usr/bin/chmod > ./new_chmod
install -m 755 /usr/bin/chmod ./new_chmod
rsync --chmod=ugo+x /usr/bin/chmod ./new_chmod
python -c "import os;os.chmod('/usr/bin/chmod', 0755)"