Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: > > sfd = fsopen("ext4", FSOPEN_CLOEXEC); > > write(sfd, "s /dev/sdb1"); // note I'm ignoring write's length arg > > Imagine some malicious program passes sfd as stdout to a setuid > program. That program gets persuaded to write "s /etc/shadow". What > happens? You’re okay as long as *every single fs* gets it right, but that’s > asking a lot. Do note that you must already have CAP_SYS_ADMIN to be able to call fsopen(). David