The impl is directly visible to the compiler so it can apply
all sorts of optimizations wherever it sees fit. And with
the previous commit they are actually "const".
This allows a service to reuse the user namespace created for an
existing service, similarly to NetworkNamespacePath=. The configuration
is the initial user namespace (e.g. ID mapping) is preserved.
Let's extract common capability parsing code into a generic function
parse_capability_set() with a comprehensive set of unit tests.
We also replace usages of UINT64_MAX with CAP_MASK_UNSET where
applicable and replace the default value of CapabilityBoundingSet
with CAP_MASK_ALL which more clearly identifies that it is initialized
to all capabilities.
AI (copilot) was used to extract the generic function and write the
unit tests, with manual review and fixing afterwards to make sure
everything was correct.
RootDirectory= but via a open_tree() file descriptor. This allows
setting up the execution environment for a service by the client in a
mount namespace and then starting a transient unit in that execution
environment using the new property.
We also add --root-directory= and --same-root-dir= to systemd-run to
have it run services within the given root directory. As systemd-run
might be invoked from a different mount namespace than what systemd is
running in, systemd-run opens the given path with open_tree() and then
sends it to systemd using the new RootDirectoryFileDescriptor= property.
RootDirectory= but via a open_tree() file descriptor. This allows
setting up the execution environment for a service by the client in
a mount namespace and then starting a transient unit in that execution
environment using the new property.
We also add --root-directory= and --same-root-dir= to systemd-run to
have it run services within the given root directory. As systemd-run
might be invoked from a different mount namespace than what systemd is
running in, systemd-run opens the given path with open_tree() and then
sends it to systemd using the new RootDirectoryFileDescriptor= property.
Hardcoding total size of the array is error-prone, especially
considering the exeuctable_fd is added far below, so the '4' is
not entirely obvious. Also we seldomly do VLAs.
If socket is used as stdio, we'd currently imply EXEC_PASS_FDS
and dump the whole set of fds to the control processes. This is
pretty much unexpected and unnecessary though, instead let's
pass only the socket fds.
Yes, this is a compat break, but a relatively minor one I'd
argue. And we can always revisit things if users do complain.
The distinction between fdstore and extra fds is only meaningful
to struct Service. As far as executor is concerned they're just
some fds to pass to the service. Let's just merge it hence,
for the sake of simplicity.
According to systemd.exec(5):
> The fd:name option connects standard input to a specific, named
> file descriptor provided *by a socket unit*. ...
Currently however we're looking at the whole fd array passed,
fix it.
Previously, we limit the length of process name by 8.
This relax the restriction then at least process comm or
program_invocation_name contains the untrucated process name.
Closes#38367.
Otherwise, e.g. requesting to start a unit that is under stopping may
enter the failed state.
This makes
- rename .can_start() -> .test_startable(), and make it allow to return
boolean and refuse to start units when it returns false,
- refuse earlier to start units that are in the deactivating state, so
several redundant conditions in .start() can be dropped,
- move checks for unit states mapped to UNIT_ACTIVATING from .start() to
.test_startable().
Fixes#39247.
Although extremely unlikely, there is a race present in solely checking the
$LISTEN_PID environment variable, due to PID recycling. Fix that by introducing
$LISTEN_PIDFDID, which contains the 64-bit ID of a pidfd for the child process
that is not subject to recycling.
Mike Yuan
Quentin Deslandes
Daan De Meyer
Yu Watanabe
Lennart Poettering
theSillywhat
Daniel Foster