When dropping the root privileges, don't try to keep the CAP_SYS_TIME
capability if the -x option was enabled. This allows chronyd to be
started without the capability (e.g. in containers) and also drop the
root privileges.
When sending client requests to a close and fast server, it is possible
that a response will be received before the HW transmit timestamp of
the request itself. To avoid processing of the response without the HW
timestamp, monitor events returned by select() and suspend reading of
packets from the receive queue for up to 200 microseconds. As the
requests are normally separated by at least 200 milliseconds, it is
sufficient to monitor and suspend one socket at a time.
If chronyc sent a request which caused chronyd to step the clock (e.g.
makestep, settime) and the second reading of the clock before calling
select() to wait for a response happened after the clock was stepped, a
new request could be sent immediately and chronyd would process the same
command twice. If the second request failed (e.g. a settime request too
close to the first request), chronyc would report an error.
Change the submit_request() function to read the clock only once per
select() to wait for the first response even when the clock was stepped.
If the system clock was stepped forward after chronyc sent a request and
before it read the clock in order to calculate the receive timeout,
select() could be called with a negative timeout, which resulted in an
infinite loop waiting for select() to succeed.
Fix the submit_request() function to not call select() with a negative
timeout. Also, return immediately on any error of select().
Instead of using the TAI-UTC offset which corresponds to the current
system time, get the offset for the reference time. This allows the
clock to be accurately stepped from a time with different TAI-UTC
offset.
This option is for indicating to chronyd that the reference clock is
kept in TAI and that chrony should attempt to convert from TAI to UTC by
using the timezone configured by the "leapsectz" directive.
Although gmtime() is expected to convert any time of the system clock at
least in the next few NTP eras, a correct code should always check the
returned value and this shouldn't be a fatal error in handling of leap
seconds.
Similarly to the maxdelaydevratio test, include in the maximum delay
dispersion which accumulated in the interval since the last sample.
Also, enable the test for symmetric associations.
Instead of giving NTP-specific data to sourcestats in order to perform
the test, provide a function to get all data needed for the test in
ntp_core. While at it, improve the naming of variables.
When (re)allocating an array with very large number of elements using
the MallocArray or ReallocArray macros, the calculated size of the array
could overflow size_t and less memory would be allocated than requested.
Add new functions for (re)allocating arrays that check the size and use
them in the MallocArray and ReallocArray macros.
This couldn't be exploited, because all arrays that can grow with cmdmon
or NTP requests already have their size checked before allocation, or
they are much smaller than memory allocated for structures to which they
are related (i.e. ntp_core and sourcestats instances), so a memory
allocation would fail before their size could overflow.
This issue was found in an audit performed by Cure53 and sponsored by
Mozilla.
Fix the UTI_TimeToLogForm() function to check if gmtime() didn't fail.
This caused chronyc to crash due to dereferencing a NULL pointer when
a response to the "manual list" request contained time which gmtime()
could not convert to broken-down representation.
This issue was found in an audit performed by Cure53 and sponsored by
Mozilla.
If no rxfilter is specified in the hwtimestamp directive and the NIC
doesn't support the all or ntp filter, enable TX-only HW timestamping
with the none filter.
On some HW it seems it's possible to get an occasional bad reading of
the PHC (with normal delay), or in a worse case the clock can step due
to a HW/driver bug, which triggers reset of the HW clock instance. To
avoid having a bad estimate of the frequency when the next (good) sample
is accumulated, drop also the last sample which triggered the reset.
If the minimum delay is known (in a static network configuration), it
can replace the measured minimum from the register. This should improve
the stability of corrections for asymmetric jitter, sample weighting and
maxdelay* tests.
Programming pins for external PHC timestamping was added in Linux 3.15,
but the PHC subsystem is older than that. Compile the programming code
only when the ioctl is defined.
