If an attribute is read but the value is not used (i.e. ret_value is NULL),
then sd_device_get_sysattr_value() mistakenly frees the read data even though
it is cached internally.
Fixes a bug introduced by acfc2a1d15.
Fixes#25702.
Sometimes a freeze operation can hang due to the presence of kernel
threads inside the unit cgroup (e.g. QEMU-KVM). This ensures that the
ThawUnit operation invoked by systemd-sleep at wakeup always thaws the
unit.
Previously, e.g., networkd enumerated network interfaces with ifindex
in a decreasing order, as sd-netlink inverses the order of the received
multipart messages.
Let's keep the order of the multipart messages. Hopefully this changes
no behavior, as our code do not depend on the order of the received
multipart messages.
Before:
===
Nov 26 09:35:10 systemd[1]: Starting Network Configuration...
Nov 26 09:35:11 systemd-networkd[36185]: wlp59s0: Saved new link: ifindex=3, iftype=ETHER(1), kind=n/a
Nov 26 09:35:12 systemd-networkd[36185]: enp0s31f6: Saved new link: ifindex=2, iftype=ETHER(1), kind=n/a
Nov 26 09:35:12 systemd-networkd[36185]: lo: Saved new link: ifindex=1, iftype=LOOPBACK(772), kind=n/a
After:
===
Nov 26 09:45:18 systemd[1]: Starting Network Configuration...
Nov 26 09:45:19 systemd-networkd[38372]: lo: Saved new link: ifindex=1, iftype=LOOPBACK(772), kind=n/a
Nov 26 09:45:19 systemd-networkd[38372]: enp0s31f6: Saved new link: ifindex=2, iftype=ETHER(1), kind=n/a
Nov 26 09:45:19 systemd-networkd[38372]: wlp59s0: Saved new link: ifindex=3, iftype=ETHER(1), kind=n/a
Previously, if a single packet contains multiple non-multipart messages,
then the messages were linked and saved as a single entry, especially
even if the messages has different serial numbers. Though, not sure if
the kernel sends such packet. But at least for safety, let's link only
multipart messages.
When we receive a multi-part message and fail to parse it, then
the prviously received message is freed with the _cleanup_ attribute,
but still referenced by sd_netlink.rqueue_partial. That causes
use-after-free when we receive another multi-part message.
This reenables epoll_pwait2() use, i.e. undoes the effect of
39f756d3ae.
Instead of just reverting that, this PR will change things so that we
strictly rely on glibc's new epoll_pwait2() wrapper (which was added
earlier this year), and drop our own manual fallback syscall wrapper.
That should nicely side-step any issues with correct syscall wrapping
definitions (which on some arch seem not to be easy, given the sigset_t
size final argument), by making this a glibc problem, not ours.
Given that the only benefit this delivers are time-outs more granular
than msec, it shouldn't really matter that we'll miss out on support
for this on systems with older glibcs.
In sd_bus_wait(), let's convert EINTR to a return code of 0, thus asking
the caller do loop again and enter sd_bus_process() again (which will
not find any queued events). This way we'll not return an error on
something that isn't really an error. This should typically make sure
things are properly handled by the caller, magically, without eating up
the event entirely, and still giving the caller time to run some code if
they want.
The compiler should recognize that these are constant expressions, but
let's better make this explicit, so that the linker can safely share the
initializations all over the place.
systemd-journald is prone to spamming logs if the system gets into
a messy state. Let's improve the situation by ratelimiting logs on
the hot code paths to 3 times per minute.
The name "def.h" originates from before the rule of "no needless abbreviations"
was established. Let's rename the file to clarify that it contains a collection
of various semi-related constants.
The function had just one caller and a name that didn't explain much.
Let's make it static and rename for clarity.
While at it, the only caller was not doing error handling correctly
— the function would potentially return a negative error value which
wasn't handled. In practice this couldn't happen, but let's remove
this ambiguity.
When running the tests in a chroot /sys/ might be writable, but it
doesn't mean udev will be running
Assertion 'sd_event_add_inotify(event, NULL, "/run/udev" , IN_DELETE, on_inotify, NULL) >= 0' failed at src/libsystemd/sd-device/test-sd-device.c:352, function test_sd_device_enumerator_filter_subsystem(). Aborting.
We treat symlinks to unit files outside of the search path differently from
symlinks to unit files *in* the search path. The former are "linked" unit
files, while the latter are enablement symlinks and such and will be removed
when disabling the unit.
The history of the check for in_search_path() is interesting: this condition
was added already in the first version of the code in
830964834f. Since the beginning, matching
arguments would simply be ignored. I think this is dubious. The man page says:
> Link a unit file that is *not* in the unit file search paths
> into the unit file search path
But for backwards-compat, let's continue to silently do nothing for files
*in* the search path.
The case of symlinks to unit files underneath the search path, but in some
subdirectory, is less clear. We didn't check for this case, so it was
implicitly allowed. But that's just an oversight, we don't want to allow people
to create additional subhierarchies under our hierarchy. Let's check for this
case and refuse.
Closes#24605.