On Mon, Jul 01, 2019 at 09:45:37AM -0700, Eric Biggers wrote: > On Sat, Jun 29, 2019 at 01:27:44PM -0700, Eric Biggers wrote: > > > > Reproducer: > > > > #include <unistd.h> > > > > #define __NR_move_mount 429 > > #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 > > > > int main() > > { > > int fds[2]; > > > > pipe(fds); > > syscall(__NR_move_mount, fds[0], "", -1, "/", MOVE_MOUNT_F_EMPTY_PATH); > > } > > David, I'd like to add this as a regression test somewhere. > > Can you point me to the tests for the new mount syscalls? > > I checked LTP, kselftests, and xfstests, but nothing to be found. FWIW, it's not just move_mount(2) - I'd expect int fds[2]; char s[80]; pipe(fds); sprintf(s, "/dev/fd/%d", fds[0]); mount(s, "/dev/null", NULL, MS_MOVE, 0); to step into exactly the same thing. mount(2) does follow symlinks - always had...