Previously, when a process outputs something and exit just after
epoll_wait() but before process_child(), then the IO event is ignored
even if the IO event has higher priority. See #18190.
This can be solved by checking epoll event again after process_child().
However, there exists a possibility that another process outputs and
exits just after process_child() but before the second epoll_wait().
When the IO event has lower priority than the child event, still IO
event is processed.
So, this makes new epoll events and child events are checked in a loop
until no new event is detected. To prevent an infinite loop, the number
of maximum trial is set to 10.
Fixes#18190.
When doing a CNAME/DNAME redirect let's first check if the answer we
already have fully answers the redirected question already. If so, let's
use that. If not, let's properly restart things.
This simply removes one call to dns_answer_reset() that was placed too
early: instead of resetting when we detect a CNAME/DNAME redirect, do so
only after checking if the answer we already have doesn't match the
reply, and then decide to *actually* follow it. Or in other words: rely
on the dns_answer_reset() call in dns_query_go() which we'll call to
actually begin with the redirected question.
This fixes an optimization path which was broken back in 7820b320ea.
(This doesn't really matter as much as one might think, since our cache
stepped in anyway and answered the questions before going back to the
network. However, this adds noise if RRs with very short TTLs are cached
– which some CDNs do – and is of course relavant when people turn off
the local cache.)
Previously by mistake we'd always match every single reply we get in a
CNAME chain to the original question from the stub client. That's
broken, we need to test it against the CNAME query we are currently
looking at.
The effect of this incorrect matching was that we'd assign the RRs to
the wrong section since we'd assume they'd be auxiliary answers instead
of primary answers.
Fixes: #18972
When responding from DNS cache, let's slightly tweak how the TTL is
lowered: as before let's round down when converting from our internal µs
to the external seconds. (This is preferable, since records should
better be cached too short instead of too long.) Let's avoid rounding
down to zero though, since that has special semantics in many cases (in
particular mDNS). Let's just use 1s in that case.
We nowadays cache full answer RRset combinations instead of just the
exact matching rrset. This means we should not cache RRs that are not
immediate answers to our question for longer then their own RRs. Or in
other words: let's determine the shortest TTL of all RRs in the whole
answer, and use that as cache lifetime.
When using hidepid=invisible on procfs, the kernel will check if the
gid of the process trying to access /proc is the same as the gid of
the process that mounted the /proc instance, or if it has the ptrace
capability:
https://github.com/torvalds/linux/blob/v5.10/fs/proc/base.c#L723https://github.com/torvalds/linux/blob/v5.10/fs/proc/root.c#L155
Given we set up the /proc instance as root for system services,
The same restriction applies to CAP_SYS_PTRACE, if a process runs with
it then hidepid=invisible has no effect.
ProtectProc effectively can only be used with User= or DynamicUser=yes,
without CAP_SYS_PTRACE.
Update the documentation to explicitly state these limitations.
Fixes#18997
These were added to eficonex.h in gnu-efi 3.0.13. Let's move them
to missing_efi.h behind an appropriate guard to fix the build with
recent versions of gnu-efi.
The integer overflow happens when utf8_encoded_valid_unichar() returns an error
code. The error code is a negative number: -22. This overflows when it is
assigned to `z` (type `size_t`). This can cause an infinite loop if the value
of `q` is 22 or larger.
To reproduce the bug, you need to run `systemd-ask-password` and enter an
invalid unicode character, followed by a backspace character.
GHSL-2021-052
Previously, when a process outputs something and exit just after
epoll_wait() but before process_child(), then the IO event is ignored
even if the IO event has higher priority. See #18190.
This can be solved by checking epoll event again after process_child().
However, there exists a possibility that another process outputs and
exits just after process_child() but before the second epoll_wait().
When the IO event has lower priority than the child event, still IO
event is processed.
So, this makes new epoll events and child events are checked in a loop
until no new event is detected. To prevent an infinite loop, the number
of maximum trial is set to 10.
Fixes#18190.
Since f17bdf8264 the test-repart was
effectively disabled, since `/dev/loop-control` is a character special
file, whereas `-f` works only on regular files. Even though we could use
`-c` to check specifically for character special files, let's use `-e`
just in case.
After all we are only interested in symlinks either in top-level config
directory or in .wants and .requires sub-directories.
As a bonus this should speed up ListUnitFiles() roughly 3-4x on systems
with a lot of units that use drop-ins (e.g. SSH jump hosts with a lot of
user session scopes).
Tables with only one column aren't really tables, they are lists. And if
each cell only consists of a single word, they are probably better
written in a single line. Hence, shorten the man page a bit, and list
boot loader spec partition types in a simple sentence.
Also, drop "root-secondary" from the list. When dissecting images we'll
upgrade "root-secondary" to "root" if we mount it, and do so only if
"root" doesn't exist. Hence never mention "root-secondary" as we never
will mount a partition under that id.
This makes sure nspawn's --volatile=yes switch works again: there we
have a read-only image that is overmounted by a tmpfs (with the
exception of /usr). This we need to mkdir all mount points even though
the image is read-only.
Hence, let's drop the optimizatio of avoiding mkdir() on images that are
read-only, it's wrong and misleading here, since the image itself might
be read-only but our mounts are not.
Previously handling of DISSECT_IMAGE_MKDIR was pretty weird and broken:
it would control both if we create the top-level mount point when
mounting an image, and the inner mount points for images that consist of
multiple file systems. However, the latter is redundant, since
1f0f82f131 does this too, a few lines
further up – unconditionally!
Hence, let's make the meaning of DISSECT_IMAGE_MKDIR more strict: it
shall be only about the top-level mount point, not about the inner ones
(where we'll continue to create what is missing alwayway). Having a
separate flag for the top-level mount point is relevant, since the mount
point dir created by it will remain on the host fs – unlike the
directories we create inside the image, which will stay within the
image.
This slightly change of meaning is actually inline with what the flag is
actually used for and documented in systemd-dissect.
Lennart Poettering
Yu Watanabe
Franck Bui
simmon
Luca Boccassi
Luca Boccassi
Daan De Meyer
Kevin Backhouse
Zbigniew Jędrzejewski-Szmek
ulf-f
Frantisek Sumsal
Michal Sekletar