TL;DR
This effectively reverts 8327fd1b11,
eaba9bb3e6, and its follow-ups, as the
original issue was already fixed by the kernel side.
The original issue that the above commits tried to 'fix' is that reading
phys_port_name triggers a lock in the kernel, hence processing multiple
interfaces at the same time causes extreme slow down.
To workaround the issue, the above commits made several necessary
information retrieved through netlink instead of sysfs attributes.
A patch set for the kernel was proposed as a fix for the issue:
https://lore.kernel.org/all/20210928125500.167943-1-atenart@kernel.org/
and some of them were merged to v5.16:
https://github.com/torvalds/linux/commit/146e5e733310379f51924111068f08a3af0db830,
It has been already backported to 5.4.160, 5.10.80, 5.14.19, and 5.15.3.
When these commits were proposed, it is already claimed that such issue
should be fixed by the kernel side, and udevd should not workaround it.
Neverthless the feature was introduced, as these have theoretical
performance improvement, even if phys_port_name sysattr does not have the
above issue, as in that way udevd can obtain multiple information about
the interface with a single netlink socket operation. See the discussion
in #20744.
However, in reality, only `iflink`, `type`, `address`, and `phys_port_name`
attributes from netlink are used in the udev net_id builtin command. Hence,
after the original issue being fixed in the kernel side, there should be
almost no performance improvement for udevd.
Furthermore, combining attributes from netlink and sysfs makes hard to
test net_id builtin. See #21725.
Let's drop mostly meaningless code, and make net_id builtin easily testable.
Closes#21725.
On socket creation respect the SELinuxContext= setting of the associated
service, such that the initial created socket has the same label as the
future process accepting the connection (since w.r.t SELinux sockets
normally have the same label as the owning process).
Triggered by #24702
In most cases we refernced the concept as "initrd". Let's convert most
remaining uses of "initramfs" to "initrd" too, to stay internally
consistent.
This leaves "initramfs" only where it's relevant to explain historical
concepts or where "initramfs" is part of the API (i.e. in
/run/initramfs).
Follow-up for: b66a6e1a58
If a root hash is specified, we should be checking that it matches
the root hash in the verity signature partition, so let's not skip
processing of the verity signature partitions if a root hash is
specified.
We need explicit support to generate read-only filesystems, since we
always need to pass a source tree to the mkfs binary to populate the
filesystem. As such, let's add an explicit check to return a
recognizable error when users try to generate a read-only filesystem
that we don't support.
With this, I can now easily do:
systemd-nspawn --load-credential=ssh.authorized_keys.root:/home/lennart/.ssh/authorized_keys --image=… --boot
To boot into an image with my SSH key copied in. Yay!
let's make things a bit less racy: whenever we create an inode,
immediately open it via O_PATH, compare type and continue operations
with the acquired fd.
In some cases it is useful to specify the access mode/uid/gid for inodes
we create without also enforcing them on existing inodes. Let's add a
new flag for that: if the uid/gid/mode specificaitons are prefixed with
":", then they only apply to creation, not otherwise.
This is specifically useful for provisioning SSH keys later. Those we'd
like to provision like this:
<snip>
d /root :0700 root root -
d /root/.ssh :0700 root root -
f^ /root/.ssh/authorized_keys - - - - ssh.authorized_keys
</snip>
While /root/ + /root/.ssh/ being owned by root is pretty uncontroversial
the access mode of /root/ and /root/.ssh/ might not be. Hence we should
only have a default mode defined that is used when we create the dir,
but not otherwise.
For some purposes we had CreationMode which indicates whether an inode
was created by us, or is pre-existing. Let's generalize that for *all*
operations. This is later useful to conditionalize certain operations on
that (and makes the codebase more systematic)
Yu Watanabe
Christian Göttsche
Luca Boccassi
Daan De Meyer
Lennart Poettering
Avamander
Daniel Braunwarth