QEMU >= 2.10 will include a CPUID leaf with value "TCGTCGTCGTCG"
on x86 when running with the TCG CPU emulator:
https://lists.gnu.org/archive/html/qemu-devel/2017-07/msg05231.html
Existing methods of detecting QEMU are left unchanged for sake of
backcompatibility.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This introduces {State,Cache,Log,Configuration}Directory= those are
similar to RuntimeDirectory=. They create the directories under
/var/lib, /var/cache/, /var/log, or /etc, respectively, with the mode
specified in {State,Cache,Log,Configuration}DirectoryMode=.
This also fixes#6391.
Trivial performance boost by explicitly bypassing the implicit
locking of stdio.
This significantly affects common cases of `journalctl` usage:
Before:
# time ./journalctl -b -1 > /dev/null
real 0m26.628s
user 0m26.495s
sys 0m0.125s
# time ./journalctl -b -1 > /dev/null
real 0m27.069s
user 0m26.936s
sys 0m0.134s
# time ./journalctl -b -1 > /dev/null
real 0m26.727s
user 0m26.607s
sys 0m0.119s
After:
# time ./journalctl -b -1 > /dev/null
real 0m23.394s
user 0m23.244s
sys 0m0.142s
# time ./journalctl -b -1 > /dev/null
real 0m23.283s
user 0m23.160s
sys 0m0.121s
# time ./journalctl -b -1 > /dev/null
real 0m23.274s
user 0m23.125s
sys 0m0.144s
Fixes https://github.com/systemd/systemd/issues/6341
When we compare two size values, let's make sure we cast from the
smaller to the bigger type first, if both types differ, rather than the
reverse in order to not run into overflows.
If the input is older than "1970-01-01 UTC", then `parse_timestamp()`
fails and returns -EINVAL. However, if the input is e.g. `-100years`,
then the function succeeds and sets `usec = 0`.
This commit makes the function also succeed for old dates and set
`usec = 0`.
Fixes#6290.
secure_getenv does not work when the process has a nonempty permitted
capability set, which means that it's unduly hard to configure logging in
systemd-logind, systemd-resolved, and others.
secure_getenv is useful for code in libraries which might get called from a
setuid application. log_parse_environment() is never called from our library
code, but directly form various top-level executables. None of them are
installed suid, and none are prepared to be used this way, since many
additional changes would be required to make that safe. We may just as well
drop the check and allow SYSTEMD_LOG_* to properly parsed.
Fixes#4900.
Commit 74dd6b515f (core: run each system
service with a fresh session keyring) broke adding keys to user keyring.
Added keys could not be accessed with error message:
keyctl_read_alloc: Permission denied
So link the user keyring to our session keyring.
When vsnprintf() truncated output, dest was advanced by the entire
size of dest leaving it just past the end. Then the fall-through \0
termination scribbled one past the end. The explicit null termination
is not necessary since vsnprintf() always includes the terminator even
when truncated.
Additionally these functions encourage calling with zero-length sizes,
while assuming non-zero sizes with potential buffer overflows.
Simply short-circuit the relevant functions when size == 0.
Fixes https://github.com/systemd/systemd/issues/6252
This extends 2d79a0bbb9 to the kernel
command line parsing.
The parsing is changed a bit to only understand "0" as infinity. If units are
specified, parse normally, e.g. "0s" is just 0. This makes it possible to
provide a zero timeout if necessary.
Simple test is added.
Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1462378.
During early boot, we'd call getrandom(), and immediately fall back to
reading from /dev/urandom unless we got the full requested number of bytes.
Those two sources are the same, so the most likely result is /dev/urandom
producing some pseudorandom numbers for us, complaining widely on the way.
Let's change our behaviour to be more conservative:
- if the numbers are only used to initialize a hash table, a short read is OK,
we don't really care if we get the first part of the seed truly random and
then some pseudorandom bytes. So just do that and return "success".
- if getrandom() returns -EAGAIN, fall back to rand() instead of querying
/dev/urandom again.
The idea with those two changes is to avoid generating a warning about
reading from an /dev/urandom when the kernel doesn't have enough entropy.
- only in the cases where we really need to make the best effort possible
(sd_id128_randomize and firstboot password hashing), fall back to
/dev/urandom.
When calling getrandom(), drop the checks whether the argument fits in an int —
getrandom() should do that for us already, and we call it with small arguments
only anyway.
Note that this does not really change the (relatively high) number of random
bytes we request from the kernel. On my laptop, during boot, PID 1 and all
other processes using this code through libsystemd request:
74780 bytes with high_quality_required == false
464 bytes with high_quality_required == true
and it does not eliminate reads from /dev/urandom completely. If the kernel was
short on entropy and getrandom() would fail, we would fall back to /dev/urandom
for those 464 bytes.
When falling back to /dev/urandom, don't lose the short read we already got,
and just read the remaining bytes.
If getrandom() syscall is not available, we fall back to /dev/urandom same
as before.
Fixes#4167 (possibly partially, let's see).
The only implementation that we care about — glibc — provides us
with 31 bits of entropy. Let's use 24 bits of that, instead of throwing
all but 8 away.
This way logind will get woken up only when an actual event took place,
and not for every key press on the system.
The ioctl EVIOCSMASK was added by @dvdhrm already in October 2015, for
the use in logind, among others, hence let's actually make use of it
now.
While we are at it, also fix usage of the EVIOCGSW ioctl, where we
assumed a byte array, even though a unsigned long native endian array is
returned.
This patch is a bit more complex thant I hoped. In particular the single
IOScheduling= property exposed on the bus is split up into
IOSchedulingClass= and IOSchedulingPriority= (though compat is
retained). Otherwise the asymmetry between setting props and getting
them is a bit too nasty.
Fixes#5613
Apart from bugs (as in #6152), this can happen if we ever make
our requirements for environment entries more stringent. As with
the rest of deserialization, we should just warn and continue.
Also called "ANSI-C Quoting" in info:(bash) ANSI-C Quoting.
The escaping rules are a POSIX proposal, and are described in
http://austingroupbugs.net/view.php?id=249. There's a lot of back-and-forth on
the details of escaping of control characters, but we'll be only using a small
subset of the syntax that is common to all proposals and is widely supported.
Unfortunately dash and fish and maybe some other shells do not support it (see
the man page patch for a list).
This allows environment variables to be safely exported using show-environment
and imported into the shell. Shells which do not support this syntax will have
to do something like
export $(systemctl show-environment|grep -v '=\$')
or whatever is appropriate in their case. I think csh and fish do not support
the A=B syntax anyway, so the change is moot for them.
Fixes#5536.
v2:
- also escape newlines (which currently disallowed in shell values, so this
doesn't really matter), and tabs (as $'\t'), and ! (as $'!'). This way quoted
output can be included directly in both interactive and noninteractive bash.
We open the target path with O_DIRECTORY|O_NOFOLLOW, and if that doesn't work,
we call unlink() on the path. In neither case we will follow the symlink, so
we can relax our check to also not follow symlinks.
Fixes#5864.
*scanf functions set errno on i/o error. For sscanf, this doesn't really apply,
so (based on the man page), it seems that errno is unlikely to be ever set to a
useful value. So just ignore errno. The error message includes the string that
was parsed, so it should be always pretty clear why parsing failed.
On the other hand, detect trailing characters and minus prefix that weren't
converted properly. This matches what our safe_ato* functions do. Add tests to
elucidate various edge cases.
