Commit Graph

54 Commits

Author SHA1 Message Date
Luca BRUNO 848fe542af
prepare-root: make all mount operations silent
This adds a `MS_SILENT` flag to all `mount(2)` calls, reducing the
amount of kernel logs produced on each boot.
Those messages do not contain actionable details, and in the "mount
plus read-only remount" case they can easily become highly redundant.
2021-10-26 10:51:37 +00:00
Luca BRUNO f4be52ba24
prepare-root: tweak log messages to clarify errors
This rewords errors and log messages in the functions which take care
of preparing sysroot in initramfs.
Depending on the boot flow, it is possible to reach this logic
with a sysroot mounted (unexpectedly) as read-only.
In that case, let's clearly point out the problematic mountpoint.
2021-10-07 14:56:47 +00:00
Jonathan Lebon dec9eab203 ostree-prepare-root: print st_dev and st_ino as 64-bit ints
This matches what systemd does and should work fine on all platforms.

Possibly resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1888436
2020-10-15 12:26:47 -04:00
Jonathan Lebon b3c7b059ea ostree-prepare-root: Fix /etc bind mount
We were bind-mounting the initramfs' `/etc` (to itself) instead of the
target deployment `/etc` (to itself). Since we're already `chdir`'ed
into it, we can just drop the leading slash.
2020-08-28 14:16:29 -04:00
Colin Walters 95a7512622 prepare-root: Remove unused variable
Should quiet Coverity.
2020-08-18 23:35:38 +00:00
Colin Walters 3564225917 Move ro /sysroot bind mount of /etc into initramfs
We recently disabled the read-only /sysroot handling:
e35b82fb89

The core problem was that a lot of services run early in the
real root and want write access to things like `/var` and `/etc`.

In trying to do remounts while the system is running we introduce
too many race conditions.

Instead, just make the `/etc` bind mount in the initramfs right
after we set up the main root.  This is much more natural really,
and avoids all race conditions since nothing is running in the
sysroot yet.

The main awkward part is that since we're not linking
`ostree-prepare-root` to GLib (yet) we have a hacky parser
for the config file.  But, this is going to be fine I think.

In order to avoid parsing the config twice, pass state from
`ostree-prepare-root` to `ostree-remount` via a file in `/run`.
2020-05-24 18:46:28 +00:00
Colin Walters d5bfbc6715 prepare-root: Add a comment about the role of this service
Came up on an IRC question, docs for this are scattered around.
2020-02-20 00:35:32 +00:00
Benjamin Gilbert 653fc6a125 prepare-root: remember to remove /sysroot.tmp
Without this, rerunning ostree-prepare-root will fail in mkdir()
because /sysroot.tmp already exists, which complicates debugging from
the dracut emergency shell.

Closes: #1919
Approved by: cgwalters
2019-09-13 12:40:57 +00:00
Tristan Cacqueray 27b7d468e6 prepare-root: remove ignored MS_MGC_VAL flag
Since Linux 2.4 this is no longer required and the flag is ignored.

Closes: #1851
Approved by: cgwalters
2019-05-05 20:53:17 +00:00
Colin Walters 304abee9eb prepare-root: Fix compilation with --with-static-compiler
Closes: https://github.com/ostreedev/ostree/issues/1845

Closes: #1846
Approved by: akiernan
2019-04-25 13:00:40 +00:00
Jonathan Lebon 298c601d88 ostree-prepare-root: Log journal message after finding deployment
Log a structured journal message when resolving the deployment path.
This will be used by the `rpm-ostree history` command to find past
deployments the system has booted into.

Closes: #1842
Approved by: cgwalters
2019-04-18 06:11:10 +00:00
Alex Kiernan 11eb0bd227 switchroot: Move late /run/ostree-booted creation to ostree-system-generator
When ostree-prepare-root is pid 1, ostree-prepare-boot defers creation of
/run/ostree-booted, which happens in ostree-remount, but that's too late
if we need ostree-system-generator to bind /var. Add the creation of the
/run/ostree-booted marker to ostree-system-generator based on the
existence of the ostree= kernel command line argument (which matches the
condition that ostree-remount uses).

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>

Closes: #1675
Approved by: cgwalters
2018-07-09 00:11:31 +00:00
Jonathan Lebon a13ea6497e switchroot: Fix regression for separately mounted /var
I made a logical error in #1617 which resulted in the exact *opposite*
behaviour we want when `/var` is a separate mount.

Split this out and lower the number of negations to make it more obvious
that it's correct.

Closes: #1667

Closes: #1668
Approved by: cgwalters
2018-07-04 16:06:38 +00:00
Jonathan Lebon ecdebeb20e switchroot: Allow letting ostree-prepare-root mount /var
In some scenarios, it might make sense to let `ostree-prepare-root` do
the `/var` mount from the state root as before. For example, one may
want to do some system configuration before the switch root. This of
course comes at the expense of supporting `/var` as a mount point in
`/etc/fstab`.

Closes: #1617
Approved by: cgwalters
2018-06-07 21:41:32 +00:00
Colin Walters fea9277020 switchroot: Don't log if running as pid1, minor code style cleanups
If we're running as pid1, avoid printing anything in the normal
success paths as we don't want to affect the physical console by
default; the device may be using a splash screen, etc.

Also cleanup the code a bit to use a single variable
`running_as_pid1`, declare-and-initialize, use the
`bool` type, etc.

Closes: #1531
Approved by: jlebon
2018-04-13 20:01:51 +00:00
Colin Walters 38cf31f6a7 switchroot: Ensure /run/ostree-booted is created even without initramfs
See https://mail.gnome.org/archives/ostree-list/2018-March/msg00012.html

If ostree-prepare-root is run as pid 1 (i.e we're not using an initramfs), then
anything we write outside the target sysroot (such as `/run/ostree-booted`) will
be lost.

Since `ostree-remount.service` runs fairly early in boot, and is triggered via
`ConditionKernelCommandLine=ostree`, we can just touch the file there in
addition.

Closes: #1508
Approved by: akiernan
2018-03-22 19:02:29 +00:00
Marcus Folkesson 6bf4b3e1d8 Add SPDX-License-Identifier to source files
SPDX License List is a list of (common) open source
licenses that can be referred to by a “short identifier”.
It has several advantages compared to the common "license header texts"
usually found in source files.

Some of the advantages:
* It is precise; there is no ambiguity due to variations in license header
  text
* It is language neutral
* It is easy to machine process
* It is concise
* It is simple and can be used without much cost in interpreted
  environments like java Script, etc.
* An SPDX license identifier is immutable.
* It provides simple guidance for developers who want to make sure the
  license for their code is respected

See http://spdx.org for further reading.

Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>

Closes: #1439
Approved by: cgwalters
2018-01-30 20:03:42 +00:00
Colin Walters 2b8d586c5a switchroot: Ensure /sysroot is set to "private" propagation
Downstream BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1498281

This came up as a problem with `oci-umount` which was trying to ensure some host
mounts like `/var/lib/containers` don't leak into privileged containers.  But
since our `/sysroot` mount wasn't private we also got a copy there.

We should have done this from the very start - it makes `findmnt` way, way less
ugly and is just the obviously right thing to do, will possibly create world
peace etc.

Closes: #1438
Approved by: rhvgoyal
2018-01-30 15:05:37 +00:00
Gatis Paeglis 62cb078973 ostree-prepare-root: enabler for simpler kernel arg
With the current approach, when ostree-prepare-root is used
on the kernel command line as init=, it always assumes that
the next value in the argument list is a path to the sysroot.
The code for falling back to a default path (if none is provided),
would only work if init= is the last arg in the argument list.
We can not rely on that and have to explicitly provide the
path to the sysroot. Which defeats the purpose of a default
path selection code.

To keep command line neater assume that sysroot is on / when
using ostree-prepare-root as init. This probably is what most
people want anyways. Also _ostree_kernel_args* API assumes
that args are space separated list. Which is problematic for:
"init=${ostree}/usr/lib/ostree/ostree-prepare-root /" as it
gets split in two.

Closes: #1401
Approved by: cgwalters
2018-01-10 13:52:58 +00:00
Colin Walters 90cd7f7234 tree-wide: Add a few missing O_CLOEXEC
I noticed an instance of this while working on https://github.com/ostreedev/ostree/pull/861
Which apparently I cargo-culted into the new system generator bits.
Let's break this out as a small concise change.

Closes: #866
Approved by: jlebon
2017-05-16 17:34:46 +00:00
Colin Walters 30705889cb Switch to using a systemd generator for /var
If one wants to set up a mount for `/var` in `/etc/fstab`, it
won't be mounted since `ostree-prepare-root` set up a bind mount for
`/var` to `/sysroot/ostree/$stateroot/var`, and systemd will take
the already extant mount over what's in `/etc/fstab`.

There are a few options to fix this, but what I settled on is parsing
`/etc/fstab` in a generator (exactly like `systemd-fstab-generator` does),
except here we look for an explicit mount for `/var`, and if one *isn't* found,
synthesize the default ostree mount to the stateroot. Another nice property is
that if an admin creates a `var.mount` unit in `/etc` for example, that will
also override our mount.

Note that today ostree doesn't hard depend on systemd, so this behavior only
kicks in if we're built with systemd *and* libmount support (for parsing
`/etc/fstab`).  I didn't really test that case though.

Initially I started writing this as a "pure libc" program, but at one point
decided to use `libostree.so` to find the booted deployment. That didn't work
out because `/boot` wasn't necessarily mounted and hence we couldn't find the
bootloader config. A leftover artifact from this is that the generator code
calls into libostree via the "cmd private" infrastructure. But it's an easy way
to share code, and doesn't hurt.

Closes: #859
Approved by: jlebon
2017-05-16 16:13:05 +00:00
Colin Walters b83d509e78 tree-wide: Switch tabs ⭾ in various files over to spaces ␠
As $DEITY intended.

I was reading the `prepare-root.c` code and the indentation damage was
distracting. Squash tabs that have leaked into various places in the code. I
didn't yet touch the `src/libostree` bits as that has higher potential for
conflict.

Closes: #852
Approved by: jlebon
2017-05-11 18:17:26 +00:00
William Manley 2aacc6912b ostree-prepare-root: Fix running with musl
musl libc's implementation of `realpath` works by opening the path and then
doing a lookup in `/proc/self/fd` to find the canonical path.  This fails
if `/proc` is not mounted.  This causes problems for us if
`ostree-prepare-root` is `init` as `/proc` won't be mounted.

We have to mount `/proc` anyway for `/proc/cmdline` so this fix just
expands the scope over which `/proc` is mounted to include both our
`realpath` calls.

See also:

* http://www.openwall.com/lists/musl/2016/06/08/2 and
* http://git.musl-libc.org/cgit/musl/tree/src/misc/realpath.c?id=e738b8cbe64b6dd3ed9f47b6d4cd7eb2c422b38d

Closes: #485
Approved by: cgwalters
2016-09-01 20:17:58 +00:00
William Manley 5424404813 ostree-prepare-root: Error if realpath fails
I've seen it fail with musl which needs `/proc` to be mounted for it to
work.  The error messages we're rather confusing before.  At least this
now points to the right location.

Closes: #485
Approved by: cgwalters
2016-09-01 20:17:58 +00:00
William Manley a128abd9bc switchroot: Replace custom error printing with err/warn functions from libc
The `warn()` libc extension has exactly the same behaviour as our own
`perrorv` function, but is available in (at least) glibc and musl.  As an
added bonus the similar function `err()` which will exit with an error
code afterwards.

This implementation is tidier and allows us to get rid of our own
`perrorv`.  It paves the way to removing `ostree-mount-util.c` to simplify
the build scripts.

Original idea by @cgwalters in #477.

Closes: #478
Approved by: cgwalters
2016-08-30 22:41:27 +00:00
William Manley 78f99d4780 ostree-prepare-root: Fix typo in error message
Closes: #403
Approved by: cgwalters
2016-08-02 19:07:25 +00:00
William Manley 6356edaaba ostree-prepare-root: Make error message capitalisation consistent
There seemed to be more lower case first letters so I've standardised
on that.

Closes: #403
Approved by: cgwalters
2016-08-02 19:07:25 +00:00
William Manley 485a374b21 ostree-prepare-root: Use pivot_root if real sysroot is already mounted at /
This allows ostree-prepare-root outside of the initramfs context where the
real rootfs is already mounted at /.  We can't use `mount --move` in this
case because we would be trying to move / into a subdirectory of itself.

Closes: #403
Approved by: cgwalters
2016-08-02 19:07:25 +00:00
William Manley 83c0fdc352 Refactor ostree-prepare-root: Perform chdir to deploy directory earlier
...for simplicity.  This way we don't need to keep concatenating
deploy_path to everything.  We can just refer relative to the current
working directory.

We need to do this after bind-mounting it over itself otherwise our cwd
is still on the non-bind-mounted filesystem below.

Closes: #403
Approved by: cgwalters
2016-08-02 19:07:25 +00:00
William Manley 47e7afab27 ostree-prepare-root: Refactor: Create /sysroot.tmp much later
Typically we have our ready made-up up root at
`/sysroot/ostree/deploy/.../` (`deploy_path`) and the real rootfs at
`/sysroot` (`root_mountpoint`).  We want to end up with our made-up root
at `/sysroot/` and the real rootfs under `/sysroot/sysroot` as systemd
will be responsible for moving `/sysroot` to `/`.

We need to do this in 3 moves to avoid trying to move `/sysroot` under
itself:

1. `/sysroot/ostree/deploy/...` -> `/sysroot.tmp`
2. `/sysroot` -> `/sysroot.tmp/sysroot`
3. `/sysroot.tmp` -> `/sysroot`

This is a refactoring to group all these operations together so I can
implement an alternative in terms of `pivot_root`.

Closes: #403
Approved by: cgwalters
2016-08-02 19:07:25 +00:00
William Manley a0a4052365 ostree-prepare-root: Cope with /proc not being mounted
When trying to read kernel command-line.

Closes: #403
Approved by: cgwalters
2016-08-02 19:07:25 +00:00
William Manley c9551dc231 ostree-prepare-root as init: exec init from deployment if run as PID1
This supports running ostree on embedded platforms without an initrd.
Specificially I'm trying to do bringup on an NVidia Tegra based Jetson TK1
dev board.

Closes: #403
Approved by: cgwalters
2016-08-02 19:07:25 +00:00
William Manley 1364e6e30d ostree-prepare-root: Refactor code to resolve deploy_path
I'll reuse this for a new ostree-init.

Closes: #403
Approved by: cgwalters
2016-08-02 19:07:25 +00:00
Colin Walters 09238da065 admin: Add an `unlock` command, and libostree API
I'm trying to improve the developer experience on OSTree-managed
systems, and I had an epiphany the other day - there's no reason we
have to be absolutely against mutating the current rootfs live.  The
key should be making it easy to rollback/reset to a known good state.

I see this command as useful for two related but distinct workflows:

 - `ostree admin unlock` will assume you're doing "development".  The
   semantics hare are that we mount an overlayfs on `/usr`, but the
   overlay data is in `/var/tmp`, and is thus discarded on reboot.
 - `ostree admin unlock --hotfix` first clones your current deployment,
   then creates an overlayfs over `/usr` persistent
   to this deployment.  Persistent in that now the initramfs switchroot
   tool knows how to mount it as well.  In this model, if you want
   to discard the hotfix, at the moment you roll back/reboot into
   the clone.

Note originally, I tried using `rofiles-fuse` over `/usr` for this,
but then everything immediately explodes because the default (at least
CentOS 7) SELinux policy denies tons of things (including `sshd_t`
access to `fusefs_t`).  Sigh.

So the switch to `overlayfs` came after experimentation.  It still
seems to have some issues...specifically `unix_chkpwd` is broken,
possibly because it's setuid?  Basically I can't ssh in anymore.

But I *can* `rpm -Uvh strace.rpm` which is handy.

NOTE: I haven't tested the hotfix path fully yet, specifically
the initramfs bits.
2016-03-23 11:09:09 -04:00
Daniel Drake 598530daf4 prepare-root: set up /boot bind-mount for single partition systems
When booting from a system with /boot on the main partition, set up
an appropriate bind mount during boot. The ostree runtime binary
expects to be able to access the bootloader configs at /boot.

See: https://mail.gnome.org/archives/ostree-list/2015-July/msg00015.html

https://bugzilla.gnome.org/show_bug.cgi?id=756267
2015-10-15 21:36:21 -04:00
Daniel Drake 5c1839c4db ostree-prepare-root: log informational messages to stdout
ostree-prepare-root was logging normal, informational messages
to stderr which the systemd unit points to the console.

To achieve silent boot, log these ordinary messages to stdout only.
2015-03-09 21:26:13 -04:00
Colin Walters ace982b51c prepare-root: Move /sysroot instead of unmounting it
I originally thought this would fix a regression, but it turns out
this wasn't the bug.  But pushing anyways as it's just cleaner.

https://bugzilla.gnome.org/show_bug.cgi?id=743891
2015-02-24 15:06:35 -05:00
Colin Walters e739677ea1 prepare-root: Update comments 2015-02-04 05:32:45 -05:00
Daniel Drake 4f75d4ea0b prepare-root: avoid double-stacked /sysroot mount
prepare-root works with the mount that has been set up at /sysroot.
It creates a bind-mount within /sysroot (the deployment) and then moves
that mount to /sysroot.

Now we have 2 mounts both at /sysroot, and once we do switch_root, we will
never be able to unmount both of them. I'm not sure if this is ultimately
a kernel bug, but either way, ostree could do a bit more tidying up
after itself.
http://thread.gmane.org/gmane.linux.file-systems/92411

Easy way to reproduce:
1. Boot with rd.break param
2. At initramfs shell, run: ostree-prepare-root /sysroot
3. Observe two /sysroot mounts in /proc/mounts

Fix this by setting up the mounts at /sysroot.tmp, and unmounting the
original /sysroot before our new mount is MS_MOVEd on top of it.
2015-02-03 20:28:37 -05:00
Giuseppe Scrivano 6a3959c895 syntax-check: Remove empty lines at the end of file
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
2015-02-02 15:07:56 +01:00
Giuseppe Scrivano e8cbd4b8c5 Remove magic argument numbers to exit(2)
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
2015-01-30 15:27:36 +01:00
Giuseppe Scrivano ea4683ba06 Remove unused <dirent.h>
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
2015-01-30 15:27:36 +01:00
Giuseppe Scrivano 7154193ae0 Remove unused include <assert.h>
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
2015-01-30 15:27:36 +01:00
Colin Walters 79fa7ca692 Add /run/ostree-booted
The idea with this is that things like yum should be able to look for
it and determine whether or not they should assume that they can
change things on the system.

https://bugzilla.gnome.org/show_bug.cgi?id=725380
2014-02-28 03:49:25 -05:00
Colin Walters 081da0033a COPYING: Now fully LGPLv2+
I ran into Jeremy Katz today, and he gave me permission to relicense
the small bits of switch-root.c to LGPLv2+.  This combined with
permission from Peter Jones allows OSTree to become fully LGPLv2+.

Not a big deal, it's just a lot clearer to only have one license, and
it makes it easier to turn application code into library code.
2013-09-11 19:57:05 -04:00
Colin Walters 9e497a4ce7 prepare-root: Fix ostree= kernel argument at end
Extracting the code for parse_ostree_cmdline() and running it on some
test input (on RHEL6.4 glibc), I can reproduce the odd behavior from
getline() where it apparently returns the size of the default malloc
buffer in the size output, and some non-zero value.

This behavior would be OK except that it breaks the logic for
stripping off the trailing newline, which in turn breaks booting
because we return "ostree=foo\n".

This has worked so far in gnome-ostree because syslinux apparently
injects initrd=/path/to/initrd as a final kernel argment.

Anyways, we don't handle NUL characters here in /proc/cmdline, so
let's just call strlen () to be safe.

https://bugzilla.gnome.org/show_bug.cgi?id=707192
2013-09-02 13:27:41 -04:00
Colin Walters 124416d832 Use AC_USE_SYSTEM_EXTENSIONS instead of #define _GNU_SOURCE
It's less copy/paste, works everywhere, etc.

Also fix some missing #include "config.h".
2013-07-10 13:25:35 -04:00
Colin Walters b5b2aca592 prepare-root: Don't be strict about the sysroot mount name here
While the systemd integration effectively requires /sysroot, it will
help people trying to use OSTree with other initramfs systems
(e.g. initramfs-tools) if we don't hardcode that requirement in this
tool.
2013-07-09 12:04:02 -04:00
Colin Walters bb6eedfb25 [INCOMPATIBLE CHANGE] Implement new deployment model
See https://wiki.gnome.org/OSTree/DeploymentModel2

This is a major rework of the on-disk filesystem layout, and the boot
process.  OSTree now explicitly supports upgrading kernels, and these
upgrades are also atomic.

The core concept of the new model is the "deployment list", which is
an ordered list of bootable operating system trees.  The deployment
list is reflected in the bootloader configuration; which has a kernel
argument that tells the initramfs (dracut) which operating system root
to use.

Invidiual notable changes that come along with this:

1) Operating systems should now come with their etc in usr/etc; OSTree
   will perform a 3-way merge at deployment time, and place etc in
   the actual root.  This avoids the need for a bind mount, and is
   just a lot cleaner.
2) OSTree no longer bind mounts /root, /home, and /tmp.  It is expected
   that the the OS/ has these as symbolic links into /var.

At the moment, OSTree only supports managing syslinux; other
bootloader backends will follow.
2013-07-07 11:31:26 -04:00
Colin Walters f6946a368f prepare-root: Only bind mount /home, /tmp, /root if they are directories
What we expect for new systems is for these to be symbolic links:
/home -> /sysroot/home
etc.
2013-06-23 17:56:14 -04:00