safe_close() automatically becomes a NOP when a negative fd is passed,
and returns -1 unconditionally. This makes it easy to write lines like
this:
fd = safe_close(fd);
Which will close an fd if it is open, and reset the fd variable
correctly.
By making use of this new scheme we can drop a > 200 lines of code that
was required to test for non-negative fds or to reset the closed fd
variable afterwards.
GCC optimizes strlen("string constant") to a constant, even with -O0.
Thus, replace patterns like sizeof("string constant")-1 with
strlen("string constant") where possible, for clarity. In particular,
for expressions intended to add up the lengths of components going into
a string, this often makes it clearer that the expression counts the
trailing '\0' exactly once, by putting the +1 for the '\0' at the end of
the expression, rather than hidden in a sizeof in the middle of the
expression.
This will let journald forward logs as messages sent to all logged in
users (like wall).
Two options are added:
* ForwardToWall (default yes)
* MaxLevelWall (default emerg)
'ForwardToWall' is overridable by kernel command line option
'systemd.journald.forward_to_wall'.
This is used to emulate the traditional syslogd behaviour of sending
emergency messages to all logged in users.
Bring some arrays that are used for DEFINE_STRING_TABLE_LOOKUP() in the
same order than the enums they reference.
Also, pass the corresponding _MAX value to the array initalizer where
appropriate.
Prior to 3.2, /proc/sys/kernel/hostname isn't a pollable file and
sd_event_add_io will return EPERM. Ignore this failure, since it isn't
critical to journald operation.
Reported and tested by user sraue on IRC.
Previously the returned object of constructor functions where sometimes
returned as last, sometimes as first and sometimes as second parameter.
Let's clean this up a bit. Here are the new rules:
1. The object the new object is derived from is put first, if there is any
2. The object we are creating will be returned in the next arguments
3. This is followed by any additional arguments
Rationale:
For functions that operate on an object we always put that object first.
Constructors should probably not be too different in this regard. Also,
if the additional parameters might want to use varargs which suggests to
put them last.
Note that this new scheme only applies to constructor functions, not to
all other functions. We do give a lot of freedom for those.
Note that this commit only changes the order of the new functions we
added, for old ones we accept the wrong order and leave it like that.
Before, journald would remove journal files until both MaxUse= and
KeepFree= settings would be satisfied. The first one depends (if set
automatically) on the size of the file system and is constant. But
the second one depends on current use of the file system, and a spike
in disk usage would cause journald to delete journal files, trying to
reach usage which would leave 15% of the disk free. This behaviour is
surprising for the user who doesn't expect his logs to be purged when
disk usage goes above 85%, which on a large disk could be some
gigabytes from being full. In addition attempting to keep 15% free
provides an attack vector where filling the disk sufficiently disposes
of almost all logs.
Instead, obey KeepFree= only as a limit on adding additional files.
When replacing old files with new, ignore KeepFree=. This means that
if journal disk usage reached some high point that at some later point
start to violate the KeepFree= constraint, journald will not add files
to go above this point, but it will stay (slightly) below it. When
journald is restarted, it forgets the previous maximum usage value,
and sets the limit based on the current usage, so if disk remains to
be filled, journald might use one journal-file-size less on each
restart, if restarts happen just after rotation. This seems like a
reasonable compromise between implementation complexity and robustness.
With this change a failing event source handler will not cause the
entire event loop to fail. Instead, we just disable the specific event
source, log a message at debug level and go on.
This also introduces a new concept of "exit code" which can be stored in
the event loop and is returned by sd_event_loop(). We also rename "quit"
to "exit" everywhere else.
Altogether this should make things more robus and keep errors local
while still providing a way to return event loop errors in a clear way.
In the time it takes to process incoming log messages, the process we
are logging details for may exit. This means the cgroup data is no
longer available from '/proc'. Unfortunately, the way the code was
structured before, we never log _SYSTEMD_UNIT if we don't have this
cgroup information.
Add an else if case that allows the passed in unit_id to be logged even
if we couldn't capture cgroup information. This ensures a command like
`journalctl -u run-XXX` will return all log messages from a oneshot
process.
Instead of individually checking for containers in each user do this
once in a new call proc_cmdline() that read the file only if we are not
in a container.
Before, when the user journal file was rotated, journal_file_rotate
could close the old file and fail to open the new file. In that
case, we would leave the old (deallocated) file in the hashmap.
On subsequent accesses, we could retrieve this stale entry, leading
to a segfault.
When journal_file_rotate fails with the file pointer set to 0,
old file is certainly gone, and cannot be used anymore.
https://bugzilla.redhat.com/show_bug.cgi?id=890463
In order to avoid a deadlock between journald looking up the
"systemd-journal" group name, and nscd (or anyother NSS backing daemon)
logging something back to the journal avoid all NSS in journald the same
way as we avoid it from PID 1.
With this change we rely on the kernel file system logic to adjust the
group of created journal files via the SETGID bit on the journal
directory. To ensure that it is always set, even after the user created
it with a simply "mkdir" on the shell we fix it up via tmpfiles on boot.
Vacuuming behaviour is a bit confusing, and/or we have some bugs,
so those additional messages should help to find out what's going
on. Also, rotation of journal files shouldn't be happening too
often, so the level of the messages is bumped to info, so that
they'll be logged under normal operation.
Since the journal can handle multiple lines just well natively,
and rsyslog can be configured to handle them as well, there is no need
to truncate messages from syslog() after the first newline.
Reproducer:
1. Add following four lines to /etc/rsyslog.conf
----------
$EscapeControlCharactersOnReceive off
$ActionFileDefaultTemplate RSYSLOG_SysklogdFileFormat
$SpaceLFOnReceive on
$DropTrailingLFOnReception off
----------
3. Restart rsyslog
# service rsyslog restart
4. Compile and run the following program
----------
#include <stdio.h>
#include <syslog.h>
int main()
{
syslog(LOG_INFO, "aaa%caaa", '\n');
return 0;
}
----------
Actual results:
Below message appears in /var/log/messages.
----------
Sep 7 19:19:39 localhost test2: aaa
----------
Expected results:
Below message, which worked prior to systemd-journald
appears in /var/log/messages.
----------
Sep 7 19:19:39 localhost test2: aaa aaa
https://bugzilla.redhat.com/show_bug.cgi?id=855313
When using Storage=none there is no point in collecting all the
information just to throw them away. After this change journald
consumes a lot less CPU time when only forwarding messages.
Reporting of the free space was bogus, since the remaining space
was compared with the maximum allowed, instead of the current
use being compared with the maximum allowed. Simplify and fix
by reporting limits directly at the point where they are calculated.
Also, assign a UUID to the message.
When journald encounters a message with OBJECT_PID= set
coming from a priviledged process (UID==0), additional fields
will be added to the message:
OBJECT_UID=,
OBJECT_GID=,
OBJECT_COMM=,
OBJECT_EXE=,
OBJECT_CMDLINE=,
OBJECT_AUDIT_SESSION=,
OBJECT_AUDIT_LOGINUID=,
OBJECT_SYSTEMD_CGROUP=,
OBJECT_SYSTEMD_SESSION=,
OBJECT_SYSTEMD_OWNER_UID=,
OBJECT_SYSTEMD_UNIT= or OBJECT_SYSTEMD_USER_UNIT=.
This is for other logging daemons, like setroubleshoot, to be able to
augment their logs with data about the process.
https://bugzilla.redhat.com/show_bug.cgi?id=951627
Since the system journal wasn't open yet, available_space() returned 0.
Before:
systemd-journal[22170]: Allowing system journal files to grow to 4.0G.
systemd-journal[22170]: Journal size currently limited to 0B due to SystemKeepFree.
After:
systemd-journal[22178]: Allowing system journal files to grow to 4.0G.
systemd-journal[22178]: Journal size currently limited to 3.0G due to SystemKeepFree.
Also, when failing to write a message, show how much space was needed:
"Failed to write entry (26 items, 260123456 bytes) despite vacuuming, ignoring: ...".
In the following scenario:
server creates system.journal
server creates user-1000.journal
both journals share the same seqnum_id.
Then
server writes to user-1000.journal first,
and server writes to system.journal a bit later,
and everything is fine.
The server then terminates (crash, reboot, rsyslog testing,
whatever), and user-1000.journal has entries which end with
a lower seqnum than system.journal. Now
server is restarted
server opens user-1000.journal and writes entries to it...
BAM! duplicate seqnums for the same seqnum_id.
Now, we usually don't see that happen, because system.journal
is closed last, and opened first. Since usually at least one
message is written during boot and lands in the system.journal,
the seqnum is initialized from it, and is set to a number higher
than than anything found in user journals. Nevertheless, if
system.journal is corrupted and is rotated, it can happen that
an entry is written to the user journal with a seqnum that is
a duplicate with an entry found in the corrupted system.journal~.
When browsing the journal, journalctl can fall into a loop
where it tries to follow the seqnums, and tries to go the
next location by seqnum, and is transported back in time to
to the older duplicate seqnum. There is not way to find
out the maximum seqnum used in a multiple files, without
actually looking at all of them. But we don't want to do
that because it would be slow, and actually it isn't really
possible, because a file might e.g. be temporarily unaccessible.
Fix the problem by using different seqnum series for user
journals. Using the same seqnum series for rotated journals
is still fine, because we know that nothing will write
to the rotated journal anymore.
Likely related:
https://bugs.freedesktop.org/show_bug.cgi?id=64566https://bugs.freedesktop.org/show_bug.cgi?id=59856https://bugs.freedesktop.org/show_bug.cgi?id=64296https://bugs.archlinux.org/task/35581https://bugzilla.novell.com/show_bug.cgi?id=817778
Possibly related:
https://bugs.freedesktop.org/show_bug.cgi?id=64293
Since 11ec7ce, journald isn't setting the ACLs properly anymore if
the files had no ACLs to begin with: acl_set_fd fails with EINVAL.
An ACL with ACL_USER or ACL_GROUP entries but no ACL_MASK entry is
invalid, so make sure a mask exists before trying to set the ACL.
Bump the minimal size of the journal so that we can be sure creating the
journal file will always succeed. Previously the minimum size was
smaller than a empty jounral file...
