For many use cases DynamicUser= just doesn't cut it. Specifically lots
of stuff wants to run as root. Let's support this use case by relaxing
our checks for capsules a bit.
Currently, NOTIFY_READY from daemon-util.h conflicts with NOTIFY_READY
from NotifyState from service.h so let's rename the constants to avoid
the conflict.
Now that the necessary functions from log.h have been moved to macro.h,
we can stop including log.h in macro.h. This requires modifying source
files all over the tree to include log.h instead.
If we unexpectly disconnect from the bus, systemd would end up dropping
the list of subscribers, which breaks the ability of clients like logind
to monitor the state of units.
Stash the list of subscribers into the deserialized state in the event
of a disconnect so that when we recover we can renew the broken
subscriptions.
---
Fixes: #8672#26744
If we unexpectly disconnect from the bus, systemd would end up dropping
the list of subscribers, which breaks the ability of clients like logind
to monitor the state of units.
Stash the list of subscribers into the deserialized state in the event
of a disconnect so that when we recover we can renew the broken
subscriptions.
Let's drop support systems lacking memfds, i.e. pre kernel 3.17 systems.
This allows us to drastically simplify the "data fd" concept, so far
that we can remove it entirely.
This replaces acquire_data_fd() with a specialized call to
memfd_new_and_seal(), not that memfds can be the only implementation of
the concept.
We noticed some failures because we have code that connects to user
managers by setting DBUS_SESSION_BUS_ADDRESS without setting XDG_RUNTIME_DIR.
If that's the case, connect to the user session bus instead of the
private manager bus as we can't connect to the latter if XDG_RUNTIME_DIR
is not set.
Let's move this check to bus_connect_transport_systemd() so that
bus_connect_system_systemd() will only ever connect to the manager
private manager bus instance and fail otherwise.
We have various callsites that explicitly need the manager bus and
won't work with the system bus, like daemon-reexec and friends which
can't properly wait until the operation has finished unless using the
manager bus.
If we silently fall back to the system bus for these operations, we
can end up with rather hard to debug issues so let's remove the fallback
as it was added back in 2013 in a6aa89122d
without a clear explanation of why it was needed (I expect as a fallback
if kdbus wasn't available but that's not a thing anymore these days).
This new helper adds all strings from a Set object as a string array to
a message.
Various places where we have similar code are then ported over to this.
When closing the FILE handle attached to a memstream, it may attempt to
do a realloc() that may fail during OOM situations, in which case we are
left with the buffer pointer pointing to NULL and buffer size > 0. For
example:
```
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
void *realloc(void *ptr, size_t size) {
return NULL;
}
int main(int argc, char *argv[])
{
FILE *f;
char *buf;
size_t sz = 0;
f = open_memstream(&buf, &sz);
if (!f)
return -ENOMEM;
fputs("Hello", f);
fflush(f);
printf("buf: 0x%lx, sz: %lu, errno: %d\n",
(unsigned long) buf, sz, errno);
fclose(f);
printf("buf: 0x%lx, sz: %lu, errno: %d\n",
(unsigned long) buf, sz, errno);
return 0;
}
```
```
$ gcc -o main main.c
$ ./main
buf: 0x74d4a0, sz: 5, errno: 0
buf: 0x0, sz: 5, errno: 0
```
This might do unexpected things if the underlying code expects a valid
pointer to the memstream buffer after closing the handle.
Found by Nallocfuzz.
In various tools and services we have a per-system and per-user concept.
So far we sometimes used a boolean indicating whether we are in system
mode, or a reversed boolean indicating whether we are in user mode, or
the LookupScope enum used by the lookup path logic.
Let's address that, in introduce a common enum for this, we can use all
across the board.
This is mostly just search/replace, no actual code changes.
Return the output of malloc_info() via a file descriptor (in case it
gets large on a busy system). Useful to get live data about memory
usage when it is not possible to run under a profiler from the get-go.
Do not formally register the method, but add a 'hidden' interface
so that it cannot be seen by introspection or by looking at the
object.