On Fri, Dec 8, 2023 at 6:37 AM Adrian Reber <areber@xxxxxxxxxx> wrote: > > The capability CAP_CHECKPOINT_RESTORE was introduced to allow non-root > users to checkpoint and restore processes as non-root with CRIU. > > This change extends CAP_CHECKPOINT_RESTORE to enable the CRIU option > '--shell-job' as non-root. CRIU's man-page describes the '--shell-job' > option like this: > > Allow one to dump shell jobs. This implies the restored task will > inherit session and process group ID from the criu itself. This option > also allows to migrate a single external tty connection, to migrate > applications like top. > > TIOCSLCKTRMIOS can only be done if the process has CAP_SYS_ADMIN and > this change extends it to CAP_SYS_ADMIN or CAP_CHECKPOINT_RESTORE. > > With this change it is possible to checkpoint and restore processes > which have a tty connection as non-root if CAP_CHECKPOINT_RESTORE is > set. > Acked-by: Andrei Vagin <avagin@xxxxxxxxx> > Acked-by: Christian Brauner <brauner@xxxxxxxxxx> > Signed-off-by: Adrian Reber <areber@xxxxxxxxxx> > --- > Changes in v2: > - replaced "if (!capable(CAP_SYS_ADMIN) && !capable(CAP_CHECKPOINT_RESTORE))" > with "if (!checkpoint_restore_ns_capable(&init_user_ns))" as suggested > by Christian Brauner > - v1: https://lore.kernel.org/linux-serial/20231206134340.7093-1-areber@xxxxxxxxxx/ > --- > drivers/tty/tty_ioctl.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c > index 4b499301a3db..85de90eebc7b 100644 > --- a/drivers/tty/tty_ioctl.c > +++ b/drivers/tty/tty_ioctl.c > @@ -844,7 +844,7 @@ int tty_mode_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) > ret = -EFAULT; > return ret; > case TIOCSLCKTRMIOS: > - if (!capable(CAP_SYS_ADMIN)) > + if (!checkpoint_restore_ns_capable(&init_user_ns)) > return -EPERM; > copy_termios_locked(real_tty, &kterm); > if (user_termios_to_kernel_termios(&kterm, > @@ -861,7 +861,7 @@ int tty_mode_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) > ret = -EFAULT; > return ret; > case TIOCSLCKTRMIOS: > - if (!capable(CAP_SYS_ADMIN)) > + if (!checkpoint_restore_ns_capable(&init_user_ns)) > return -EPERM; > copy_termios_locked(real_tty, &kterm); > if (user_termios_to_kernel_termios_1(&kterm, > > base-commit: 98b1cc82c4affc16f5598d4fa14b1858671b2263 > -- > 2.43.0 >
