Let's drop unused function arguments, and needless double pointers where
we can.
no actual change in behaviour, just simplifications
(I tried to track down #14026 without success, and this came out of it)
The implementation is a bit ugly because we set the output variable
twice. But we were already doing this on error, so this is not
significantly worse. Doing this allows us to avoid goto's, and the
compiler should be able to figure this out and only set once.
We'd return -1 (-EPERM), even though we have a general rule to use real errno
values. The particular case that caught my attention was:
$ sudo udevadm control -l asdf
Failed to parse log priority 'asdf': Operation not permitted
... but "git grep 'r =.*_from_string' src/" return 110 hits. Confusingly, some
of the _from_string functions already return a proper errno value, so not all
of those are broken, but probably quite a few.
As suggested in https://github.com/systemd/systemd/pull/11484#issuecomment-775288617.
This does not touch anything exposed in src/systemd. Changing the defines there
would be a compatibility break.
Note that tests are broken after this commit. They will be fixed in the next one.
A hole was/is present after the booleans, so changing them to be one byte each
doesn't change the structure size (122 bits on amd64). If we add more stuff
later, it might make sense to turn some of those into bitfields again. For now,
let's take the easy route. EINVAL fits into type now.
Code size it minimally reduced:
-rwxrwxr-x 1 zbyszek zbyszek 4109792 Feb 10 14:00 build/libsystemd.so.0.30.0
-rwxrwxr-x 1 zbyszek zbyszek 4109712 Feb 10 14:01 build/libsystemd.so.0.30.0
By rearranging the fields, we can avoid one of the holes (on amd64).
By adding more space for .type, -EINVAL can be used as a value later on.
The structure is reduced from 96 to 88 bytes (on amd64).
Text size is also smaller:
-rwxrwxr-x 1 zbyszek zbyszek 4109832 Feb 9 19:50 build/libsystemd.so.0.30.0
-rwxrwxr-x 1 zbyszek zbyszek 4109792 Feb 9 19:51 build/libsystemd.so.0.30.0
Every bitfield may make the object a little smaller, but requires additional
code when accessing the field. So it only makes sense in objects that are
created in many many copies. The Manager is pretty much a singleton.
-rwxrwxr-x 1 zbyszek zbyszek 4443840 Feb 9 16:14 build/systemd
-rwxrwxr-x 1 zbyszek zbyszek 4442552 Feb 9 16:42 build/systemd
We save 1288 bytes of code by "wasting" a few bytes on storage. (The speed
advantages are probably more important, but harder to measure…)
Doing it all in one line and with negation in front seemed like a good
idea at some point, but I think it is vastly easier to understand when
it is split out a bit.
This improves the output of the "list" and "info" verbs and adds
coredump size information to the output.
For doing that a common helper function is added that analyzes the
coredump file on disk.
Let's use our table formatter for generating the coredump table. Bring
support up to our current standards, with a bit of color, JSON output
and so on.
Also adds supports for setting a max for the number of lines to
generate. (with the new -n switch)
The existing -1 switch now becomes a synonym for "-n 1 --reverse"
Fixes: #3271
This way we can display invalid UIDs/GIDs/PIDs as n/a while still
storing them as is.
Also, let's add a new cell type for unix signal, that is stored as
integer, but displayed as signal name string.
Some folks argue that NOTIMP should only be returned if a specific QTYPE
is not supported. While I don#t think the RFCs are too clear about that,
let's use REFUSED instead, which appears to be a less controversial
choice of error code.
Prompted-by: #17218
This substantially beefs up the local DNS stub feature set in order to
allow local clients to do DNSSEC validation through the stub.
Previously we'd return NOTIMP if we'd get a DO or DO+CD lookup. With
this change we'll instead:
1. If we get DO+CD requests (i.e. DNSSEC with no local checking) we'll
proxy DNS queries and response mostly unmodified to/from upstream DNS
servers if possible (this is called "bypass" mode). We will patch in
new request IDs, (and patch them back out on reply), so that we can
sanely keep track of things. We'll also maintain a minimal local
cache for such lookups, always keeping the whole DNS packets in it
(if we reply from cache we'll patch the TTLs of all included RRs).
2. If we get DO requests without CD (i.e. DNSSEC with local checking)
we'll resolve and validate locally. In this mode we will not proxy
packets, but generate our own. We will however cache the combination
of answer RRs (along with their packet section assignments) we got
back in the cache, and use this information to generate reply packets
from the DNS stub.
In both cases: if we determine a lookup is to be answered from LLMNR or
mDNS we'll always revert to non-DNSSEC, non-proxy operation as before.
Answers will lack the DO bit then, since the data cannot be validated
via DNSSEC by the clients.
To make this logic more debuggable, this also adds query flags for
turning off RR sources. i.e. cache/network/zone/trust anchor/local
synthesis may now be disabled individually for each lookup.
The cache is substantially updated to make all this work: in addition to
caching simple RRs for lookup RR keys, we'll now cache the whole packets
and the whole combination of RRs, so that we can answer DO and DO+CD
replies sensibly according to the rules described above. This sounds
wasteful, but given that the
DnsResourceRecord/DnsResourceKey/DnsAnswer/DnsPacket
objects are all ref-counted and we try to merge references the actual
additional memory used should be limited (but this might be something to
optimize further later on).
To implement classic RR key lookups and new-style packet proxy lookups
(i.e. the ones necessary for DO+CD packet proxying, as described above)
DnsTransaction and DnsQuery objects now always maintain either a
DnsResourceKey/DnsQuestion as lookup key or a DnsPacket for "bypass"
mode.
Fixes: #4621#17218
This is useful later when handling the truncation case: if we can't add
all RRs we'd like to add we need to set the TC bit, but still report the
number of RRs we added (and not the number of RRs we would have liked to
add) to the packet.
Let's beef up our parser a bit: let's store in the DnsAnswerFlags field
(that is stored as part of DnsAnswerItem) which DNS packet section (i.e.
answer, authoritative, additional) an RR originates from.
This is useful when propagating answers from an upstream DNS server
eventually, as we can place the data in the right sections downstream
too.
The more fields DnsAnswerItem gains the less sense it makes to pass
every field of it as separate parameter to an iterator macro. Let's
simplify things here, in preparation of adding more fields to the
structure later on: let's just return the structure itself in the loop,
rather than the individual fields.
This is a simple search&replace excercise: instead of accessing the
"key" field of the transaction directly, let's use a small inline helper
that does this for us.
This appears pointless for now, but this will become useful later when
we introduce "bypass" transactions, that reuse the original client DNS
packet for queries instead of synthesizing a packet of our own. In that
case transactions either have regular "key" field initialized as before,
or the "bypass" packet field instead. The new dns_transaction_key()
helper allows us to hide the differences for most cases as we can later
teach it to access the "bypass" packet's question key transparently.
No change in behaviour.
systemd-inhibit when invoked with a command line will put the whole
command line in the "who" field of the inhibitor lock. This can get
extremely long for shell expressions, making the table "systemd-inhibit
--list" shows ridiculously weirdly formatted. Let's put a limit on the
column width: half of the screen, not more.
If one field in a specific column has a maximum size limit, other fields
in the same column might affected by it and get less than they asked
for. Let's make sure we can handle this, and don't assert on this
because surprisingly we got less than what we asked for.
Does what the name suggests. Obviously inspired by sudoers, but note that
our tools are not supposed to be installed suid, so there is no privilege
boundary to cross here.
We have a number of issues where oss-fuzz reports input-independent crashes of
fuzz-journal-remote. Instead of asserting that stuff that allocated fds and
memory never fails, let's instead just return an error.
https://oss-fuzz.com/testcase-detail/4791099424112640https://oss-fuzz.com/testcase-detail/4531912477638656
I don't see any docs as to whether LLVMFuzzerTestOneInput() is allowed to
return non-zero. Propagating the error code is easiest, so let's just do that.
If it turns out that this causes oss-fuzz to still report a failure, we can
suppress that later.
Setting of IPv6 Proxy NDP addresses must be done at the same
time as static addresses, static routes, and other link attributes
that must be configured when the link is up. Doing this ensures
that they are reconfigured on the link if the link goes down
and returns to service.
There may be situations where a cgroup should be protected from killing
or deprioritized as a candidate. In FB oomd xattrs are used to bias oomd
away from supervisor cgroups and towards worker cgroups in container
tasks. On desktops this can be used to protect important units with
unpredictable resource consumption.
The patch allows systemd-oomd to understand 2 xattrs:
"user.oomd_avoid" and "user.oomd_omit". If systemd-oomd sees these
xattrs set to 1 on a candidate cgroup (i.e. while attempting to kill something)
AND the cgroup is owned by root, it will either deprioritize the cgroup as
a candidate (avoid) or remove it completely as a candidate (omit).
Usage is restricted to root owned cgroups to prevent situations where an
unprivileged user can set their own cgroups lower in the kill priority than
another user's (and prevent them from omitting their units from
systemd-oomd killing).
