This contains the "bootctl install" related work from the #38764 split
out, but also includes the preparatory work already split out into
#40446.
I'll rebase this PR once the prep work is merged.
This has a simple CI test already, and has docs
When a cgroup is selected for termination, send varlink messages
to hooks registered in `/run/systemd/oomd.prekill-hooks/`.
oomd waits up to `PreKillHookTimeoutSec=` seconds for response
before proceeding with the kill.
This reverts commit 332bce5bd7.
The revert is needed because with the PreKill hook, oomd_cgroup_kill()
is not goint to really kill processes but it just creates the callbacks.
So the check is deferred to the real kill.
When systemd is compiled with group-render-mode=0660, only the active
seat gets access to the render devices through uaccess. Remote desktop
sessions like gnome-remote-desktop would be left with no hardware
rendering, because those sessions are not associated with a seat.
We solve the issue by granting uaccess to specifically tagged devices on
session start, if the session is marked with
XDG_SESSION_EXTRA_DEVICE_ACCESS.
udev-builtin-uaccess is refactored to grant multiple users access to a
device, taking into account the device's seat and all the active
EXTRA_DEVICE_ACCESS sessions.
Let's count how many sources we skip, and output that as a summary, and
return an error exit code in this case.
Let's also put a limit on the metrics collected, not just the sources.
Also, our macros that put limits on things are usually called XYZ_MAX,
follow the same scheme here.
Let's also move the Varlink connection management into the Context
object. Let's also switch to Set* for it, so that we get get
auto-expanding behaviour.
It's one of the primary objects that make up the program "context"
conceptually, hence it also should be part of the Context object. This
allows us to just have it available if the Context object is seen.
We should permit that the report varlink dir is created on the fly when
the first socket is bound there. Hence, let's treat a non-existant dir
equivalent to an empty one.
We usually do this in our tree like this, do it here too.
This partially reverts 36c557f7d4, which
introduced notify_remove_fd() that logs in LOG_DEBUG. However,
notify_remove_fd_warn() is still called other library functions, e.g.
notify_push_fd(), and produces warning message about the failure in
removing fd from fdstore on shutdown.
During shutdown process, we get the following logs:
```
systemd-udevd[370]: Failed to send notify message to '/run/systemd/notify': Connection refused
systemd-udevd[370]: Failed to remove file descriptor "config-serialization" from the store, ignoring: Connection refused
systemd-udevd[370]: Failed to send notify message to '/run/systemd/notify': Connection refused
systemd-udevd[370]: Failed to push serialization fd to service manager: Connection refused
```
Here, the 1st, 3rd, and 4th messages are in LOG_DEBUG, but the 2nd one
was in LOG_WARNING before this commit, and this makes it also in LOG_DEBUG.
Follow-up for 472404aca5.
Historically, resolvectl status has not included the interface
specification for DNS servers with an IPv6 link-local address, since it
is technically somewhat redundant. But, adding this extra bit of
information makes it easier to copy-and-paste to use elsewhere, etc.
For example, the previous output:
Link 2 (enp34s0)
Current Scopes: DNS LLMNR/IPv4 LLMNR/IPv6
Protocols: +DefaultRoute LLMNR=resolve -mDNS -DNSOverTLS DNSSEC=no/unsupported
Current DNS Server: fe80::861e:a3ff:feb1:f8e7
DNS Servers: 192.168.1.12 192.168.1.13 fe80::861e:a3ff:feb1:f8e7
DNS Domain: lan
now becomes:
Link 2 (enp34s0)
Current Scopes: DNS LLMNR/IPv4 LLMNR/IPv6
Protocols: +DefaultRoute LLMNR=resolve -mDNS -DNSOverTLS DNSSEC=no/unsupported
Current DNS Server: fe80::861e:a3ff:feb1:f8e7%2
DNS Servers: 192.168.1.12 192.168.1.13 fe80::861e:a3ff:feb1:f8e7%2
DNS Domain: lan
When running "bootctl install" on an empty --root= dir, we don't know
which token to use, and the operation will fail. Make sure to return an
explicit error about this.
This introduces a recognizable low-level error for this (EUNATCH), and
then turns this into a recognizable Varlink error.
(I made sure that the old low-level error EINVAL wasn't load-bearing,
and it is safe to change this.)
This primarily introduces a context object for each operation, so that
we later can instantiate one for each varlink op we execute, and can
safely lifecycle all operation parameters for each subequent call.
This also reworks the root dir handling to be fd based.
This drops explicit CHASE_TRIGGER_AUTOFS from a bunch of chase() calls
that operate within the ESP/XBOOTLDR, while it keeps them in place for the
chase() calls that find the top-level ESP/XBOOTLDR inode. This reflects
the fact that we explicitly support autofs for the ESP/XBOOTLDR itself,
but below it expect no further mounts, just plain VFAT.
This changes behaviour of the interaction of $KERNEL_INSTALL_CONF_ROOT
and --root=: the former will now be taken relative to the host root, and
will no longer be affected by --root=. This follows similar behaviour in
kernel-install, where it is very explicitly documented in the man page
(the bootclt man page does not document this). This is strictly speaking
a compat breakage, but i think a very minor, niche one, and I think the
pain afflicted by this change is probably neglible compare to the
unsystematic behaviour comapred to kernel-install.
Grant access to devices tagged with "xaccess" on session start, if the session
was created with XDG_SESSION_EXTRA_DEVICE_ACCESS=1.
udev-builtin-uaccess is refactored to grant multiple users access to a device,
taking into account the device's seat and all the active EXTRA_DEVICE_ACCESS
sessions.
A session created with XDG_SESSION_EXTRA_DEVICE_ACCESS will be granted
additional powers.
Exactly which powers are granted is going to be defined by udevd.
The code here assumes that free_user_ns() is called for every single
user namespace. That however has never been the case and the logic for
free_user_ns() is a bit more involved.
A nested user namespace pins its parent user namespace. IOW, the
lifetime of the parent user namespaces is at least as long as the child
user namespaces.
If a parent user namespace becomes unused (no namespace file descriptors
or task using it anymore) then it will stick around and its lifetime
still bound to the child user namespace.
free_user_ns() takes advantage of that behavior. If a child user
namespace is freed and its parent user namespace is already unused then
then free_user_ns() will free both the child and the parent user
namespace. This means a single free_user_ns() frees two user namespaces.
Hence, the bpf program never sees the parent user namespace being freed.
We can fix this by piggy-backing on another function that is called for
every single user namespace being freed. This requires CONFIG_SYSCTL but
systemd doesn't work without that anyway.
The return type needs to change to a scalar type as required by libbpf.
Long-term what we need is appropriate LSM infrastructure for this
including hooks that get called on namespace destruction.
Thanks to Daan DeMeyer for figuring out that the cast is needed.
Signed-off-by: Christian Brauner <brauner@kernel.org>
open_tree() will fail with EINVAL when passed a directory file descriptor
that comes from another mount namespace. While this should be fixed in a
future kernel, let's workaround the issue for now by entering the mount
namespace of the peer if needed and calling open_tree() there and then
passing the fd back to the mountfsd process.
name_to_handle_at_try_unique_mntid_fid() in its current form is
ill-designed for various reasons:
* AT_HANDLE_FID requires file system support, while unique mount id
is a VFS concept hence is always available if supported. Hence
the fallback for AT_HANDLE_MNT_ID_UNIQUE should be independent
of fid.
* The request for AT_HANDLE_MNT_ID_UNIQUE can be identified via
specifying ret_unique_mnt_id, no need for opening up the control
to caller (and currently the function simply doesn't handle
mismatch between ret params and flags).
* The caller cannot realistically differentiate whether the returned
mount id is actually unique.
* The path_get_unique_mnt_id() fallback did not handle AT_SYMLINK_FOLLOW.
Let's instead move the statx() fallback into name_to_handle_at_loop()
directly, and revamp interaction of ret_mnt_id/ret_unique_mnt_id:
if both are set, it indicates that the caller can handle both, hence
set what we have and return 0/1 for whether we managed to acquire
the unique one.
The !ret_handle && ret_mnt_id logic is removed. Let's not rely on
undocumented bizaare behavior and it's unused anyways.
path_get_mnt_id_at() exists for a reason...
Daan De Meyer
Mike Yuan
Matteo Croce
Daan De Meyer
Lennart Poettering
Yu Watanabe
Nick Rosbrook
Alessandro Astone
Louis Stagg
Christian Brauner