(1) is mostly right. The actual restriction is that ".." will be a no-op if the current directory is equal to nd->root (what your current root is). (2) Yes, ea

(1) is mostly right. The actual restriction is that ".." will be a no-op if the current directory is equal to nd->root (what your current root is). (2) Yes, each process only has one root at a time. (3) The restrictions don't apply to file handles at all (an fd doesn't know what chroot it was created in). Instead what happens is that the restriction in (1) is useless once the current directory of the resolution is above the nd->root (after all, a directory above nd->root is not equal to nd->root).