The kernel finally has a proper API to determine the mnt_id of a file.
Let's use it.
This adds support for the STATX_MNT_ID field of statx(), added in
kernel 5.8.
This was needed before commit 16e4fd87c5 added a
mode that opens the log fds for every single log message. This mode is used in
execute.c since then making the explicit call to log_open unnecessary.
This basically reverts ea89a119cd.
glibc 2.26 lifted restrictions on search domains count or length to
unlimited. This has also been backported to 2.17 in some distributions (RHEL 7
and derivatives). Other softwares may have their own limits for search domains,
but we should not restrict what is written out any more.
https://sourceware.org/legacy-ml/libc-announce/2017/msg00001.html
Unprivileged test-fs-util fails on my system since /sys/dev/block is
inaccessible for unprivileged users, so let's skip encrypted path test if we
get EACCES or similar.
If we don't succeed on the first try it's because another process is
opening the same device. Do a microsleep for 2ms to increase the
chances it has completed the next time around the loop.
The symlink /dev/mapper/dm_name is created by udev after a mapper
device is set up. So libdevmapper/libcrypsetup might tell us that
a verity device exists, but the symlink we use as the source for
the mount operation might not be there yet.
Instead of falling back to a new unique device set up, wait for
the udev event matching on the expected devlink for at least 100ms
(after which the benefits of sharing a device in terms of setup
time start to disappear - on my production machines, opening a new
verity device seems to take between 150ms and 300ms)
This effectively makes little difference because we exit soon later
anyway, which will close the fds, too. However, it's still useful since
it means the parent will get EOF events on them in the order we process
things and isn't delayed to process the data from the pipes until the
child dies.
Let's use a proper table for outputting partition information. Let's
also put the general information about the image first, and the table
after that.
Moreover, dissect the image before showing any output, so that we can
early on return an error if the image is not valid.
That way we can turn off kernel partition scanning if verity data is
available (as we don't support verity for full GPT images, only for
simple file system images).
LOOP_CONFIGURE allows us to configure a loopback device in one ioctl
instead of two, which is not just faster but also removes the race that
udev might start probing the device before we adjusted things properly.
Unfortunately LOOP_CONFIGURE is broken in regards to LO_FLAGS_PARTSCAN
as of kernel 5.8.0. This patch contains a work-around for that, to
fallback to old behaviour if partition scanning is requested but does
not work. Sucks a bit.
Proposed upstream fix for that issue:
https://lkml.org/lkml/2020/8/6/97
The machine-id is used to create a few directories and setup a default
loader entry in loader.conf. Having bootctl create the directories
itself is not particularly useful as it does not put anything in them
and bootctl install is not guaranteed to be called before an initramfs
tool like kernel-install so other programs will always need to have
logic to create the directories themselves if they happen to be called
before bootctl install is called.
On top of this, when using unified kernel images, these are installed to
$BOOT/EFI/Linux which removes the need to have the directories created
by bootctl at all. This further indicates that these directories should
be created by the program that puts something in them rather than by
bootctl.
Removing the machine-id dependency allows bootctl install to be called
even when there's no machine-id in the image. This is useful for image
builders such as mkosi which don't have a machine-id when
installing systemd-boot (via bootctl) because it should only be
generated by systemd when the final image is booted.
The default entry in loader.conf based on the machine-id in loader.conf
is also removed which shouldn't be a massive loss in usability overall.
This commit reverts commit 341890d.
Lennart Poettering