On Wed, Aug 23, 2017 at 2:43 AM, Ben Hutchings <b...@decadent.org.uk> wrote: >> > > > On Mon, 2017-08-14 at 16:42 +0200, Denys Vlasenko wrote: >> > > > > > > run-init >> > > > > >> > > > > This tool is doing this: >> > > > >> > > > [...] >> > > > > There is the "switch_root" tool in util-linux which does the >> > > > > crucial part of this functionality - deleting / remounting / >> > > > > chrooting. >> > > > > It is in bbox too. >> > > > >> > > > initramfs-tools used to use switch_root if possible, but it >> > > > didn't >> > > > support the -d (drop capabilities) option. Later on we needed >> > > > validation of the init filename to support symlinks (e.g. >> > > > /sbin/init -> >> > > > /lib/systemd/systemd), so I added and used the -n (dry run) >> > > > option to >> > > > run-init. busybox would need to support both of these. >> > > >> > > I added run-init to busybox just now, but I don't see -n option >> > > in >> > > klibc-2.0.4 source. Can you point me to the source code with -n? >> > >> > It's not upstream yet, but in a Debian patch: >> > https://sources.debian.net/src/klibc/2.0.4-9/debian/patches/run-ini >> > t-add-dry-run-mode.patch/ >> >> Done: >> >> $ ./busybox run-init >> BusyBox v1.28.0.git (2017-08-21 18:55:09 CEST) multi-call binary. >> >> Usage: run-init [-d CAP,CAP...] [-n] [-c CONSOLE_DEV] NEW_ROOT >> NEW_INIT [ARGS] >> >> Free initramfs and switch to another root fs: >> chroot to NEW_ROOT, delete all in /, move NEW_ROOT to /, >> execute NEW_INIT. PID must be 1. NEW_ROOT must be a mountpoint. >> >> -c DEV Reopen stdio to DEV after switch >> -d CAPS Drop capabilities >> -n Dry run > > Great. Once these changes are in the Debian package, I can update > initramfs-tools to make klibc-utils optional.
busybox 1.28.0 is released, it contains the addition of run-init.
