On 17/03/2020 17:47, Al Viro wrote: > On Mon, Feb 24, 2020 at 05:02:11PM +0100, Mickaël Salaün wrote: > >> +static int get_path_from_fd(u64 fd, struct path *path) > >> + /* >> + * Only allows O_PATH FD: enable to restrict ambiant (FS) accesses >> + * without requiring to open and risk leaking or misuing a FD. Accept >> + * removed, but still open directory (S_DEAD). >> + */ >> + if (!(f.file->f_mode & FMODE_PATH) || !f.file->f_path.mnt || > ^^^^^^^^^^^^^^^^^^^ > Could you explain what that one had been be about? The underlined > subexpression is always false; was that supposed to check some > condition and if so, which one? > This was just to be sure that the next assignment "path->mnt = f.file->f_path.mnt;" always creates a valid path. If this is always true, I will remove it.