A follow-up to r337812 to catch a couple more memory leaks that should
have been included in that change.
Reported by: Coverity
CID: 1296064, 1296067 (for real this time)
MFC after: 3 days
X-MFC-with: r337812
Sponsored by: Dell EMC
The libkqueue tests have several places that leak memory by using an
idiom like:
puts(kevent_to_str(kevp));
Rework to save the pointer returned from kevent_to_str() and then
free() it after it has been used.
Reported by: asomers (pointer to Coverity), Coverity
CID: 1296063, 1296064, 1296065, 1296066, 1296067, 1350287, 1394960
Sponsored by: Dell EMC
Create loader_{4th,lua,simp}{,.efi}. All of these are installed by
default. Create LOADER_DEFAULT_INTERP to specify the default
interpreter when no other is specified. LOADER_INTERP is the current
interpreter language building. Turn building of lua on by default to
match 4th. simploader is a simplified loader build w/o any interpreter
language (but with a simple loader). This is the historic behavir you
got with WITHOUT_FORTH. Make a hard link to the default loader. This
has to be a hard link rather than the more desirable soft link because
older zfsboot blocks don't support symlinks.
RelNotes: Yes
Differential Revision: https://reviews.freebsd.org/D16705
Previous iteration of this assumed that these won't fail because we've
already setup the jail param to this point, but the allocations could still
fail in pretty bad conditions.
Admit that it's possible and return (ENOENT, EINVAL, ENOMEM, or 0) when
deleting arguments. EINVAL shouldn't happen since we're passing optarg;
which may satisfy *optarg == '\0' but never optarg == NULL.
CID: 1394885, 1394901
Currently, the limits are quite high. On machines with millions of
mbuf clusters, the reassembly queue limits can also run into
the millions. Lower these values.
Also, try to ensure that no bucket will have a reassembly
queue larger than approximately 100 items. This limits the cost to
find the correct reassembly queue when processing an incoming
fragment.
Due to the low limits on each bucket's length, increase the size of
the hash table from 64 to 1024.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
In particular, try to ensure that no bucket will have a reassembly
queue larger than approximately 100 items. This limits the cost to
find the correct reassembly queue when processing an incoming
fragment.
Due to the low limits on each bucket's length, increase the size of
the hash table from 64 to 1024.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
On the guest entry in bhyve, flush L1 data cache, using either L1D
flush command MSR if available, or by reading enough uninteresting
data to fill whole cache.
Flush is automatically enabled on CPUs which do not report RDCL_NO,
and can be disabled with the hw.vmm.l1d_flush tunable/kenv.
Security: CVE-2018-3646
Reviewed by: emaste. jhb, Tony Luck <tony.luck@intel.com>
Sponsored by: The FreeBSD Foundation
Currently, we process IPv6 fragments with 0 bytes of payload, add them
to the reassembly queue, and do not recognize them as duplicating or
overlapping with adjacent 0-byte fragments. An attacker can exploit this
to create long fragment queues.
There is no legitimate reason for a fragment with no payload. However,
because IPv6 packets with an empty payload are acceptable, allow an
"atomic" fragment with no payload.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
There is a hashing algorithm which should distribute IPv6 reassembly
queues across the available buckets in a relatively even way. However,
if there is a flaw in the hashing algorithm which allows a large number
of IPv6 fragment reassembly queues to end up in a single bucket, a per-
bucket limit could help mitigate the performance impact of this flaw.
Implement such a limit, with a default of twice the maximum number of
reassembly queues divided by the number of buckets. Recalculate the
limit any time the maximum number of reassembly queues changes.
However, allow the user to override the value using a sysctl
(net.inet6.ip6.maxfragbucketsize).
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
The IPv4 fragment reassembly code supports a limit on the number of
fragments per packet. The default limit is currently 17 fragments.
Among other things, this limit serves to limit the number of fragments
the code must parse when trying to reassembly a packet.
Add a limit to the IPv6 reassembly code. By default, limit a packet
to 65 fragments (64 on the queue, plus one final fragment to complete
the packet). This allows an average fragment size of 1,008 bytes, which
should be sufficient to hold a fragment. (Recall that the IPv6 minimum
MTU is 1280 bytes. Therefore, this configuration allows a full-size
IPv6 packet to be fragmented on a link with the minimum MTU and still
carry approximately 272 bytes of headers before the fragmented portion
of the packet.)
Users can adjust this limit using the net.inet6.ip6.maxfragsperpacket
sysctl.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
The IPv6 reassembly fragment limit is based on the number of mbuf clusters,
which are a global resource. However, the limit is currently applied
on a per-VNET basis. Given enough VNETs (or given sufficient customization
on enough VNETs), it is possible that the sum of all the VNET fragment
limits will exceed the number of mbuf clusters available in the system.
Given the fact that the fragment limits are intended (at least in part) to
regulate access to a global resource, the IPv6 fragment limit should
be applied on a global basis.
Note that it is still possible to disable fragmentation for a particular
VNET by setting the net.inet6.ip6.maxfragpackets sysctl to 0 for that
VNET. In addition, it is now possible to disable fragmentation globally
by setting the net.inet6.ip6.maxfrags sysctl to 0.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
There is a hashing algorithm which should distribute IPv4 reassembly
queues across the available buckets in a relatively even way. However,
if there is a flaw in the hashing algorithm which allows a large number
of IPv4 fragment reassembly queues to end up in a single bucket, a per-
bucket limit could help mitigate the performance impact of this flaw.
Implement such a limit, with a default of twice the maximum number of
reassembly queues divided by the number of buckets. Recalculate the
limit any time the maximum number of reassembly queues changes.
However, allow the user to override the value using a sysctl
(net.inet.ip.maxfragbucketsize).
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
The IP reassembly fragment limit is based on the number of mbuf clusters,
which are a global resource. However, the limit is currently applied
on a per-VNET basis. Given enough VNETs (or given sufficient customization
of enough VNETs), it is possible that the sum of all the VNET limits
will exceed the number of mbuf clusters available in the system.
Given the fact that the fragment limit is intended (at least in part) to
regulate access to a global resource, the fragment limit should
be applied on a global basis.
VNET-specific limits can be adjusted by modifying the
net.inet.ip.maxfragpackets and net.inet.ip.maxfragsperpacket
sysctls.
To disable fragment reassembly globally, set net.inet.ip.maxfrags to 0.
To disable fragment reassembly for a particular VNET, set
net.inet.ip.maxfragpackets to 0.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
Currently, all IPv6 fragment reassembly queues are kept in a flat
linked list. This has a number of implications. Two significant
implications are: all reassembly operations share a common lock,
and it is possible for the linked list to grow quite large.
Improve IPv6 reassembly performance by hashing fragments into buckets,
each of which has its own lock. Calculate the hash key using a Jenkins
hash with a random seed.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
Currently, IPv4 fragments are hashed into buckets based on a 32-bit
key which is calculated by (src_ip ^ ip_id) and combined with a random
seed. However, because an attacker can control the values of src_ip
and ip_id, it is possible to construct an attack which causes very
deep chains to form in a given bucket.
To ensure more uniform distribution (and lower predictability for
an attacker), calculate the hash based on a key which includes all
the fields we use to identify a reassembly queue (dst_ip, src_ip,
ip_id, and the ip protocol) as well as a random seed.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
We always zero the invalidated PTE/PDE for superpage, which means that
L1TF CPU vulnerability (CVE-2018-3620) can be only used for reading
from the page at zero.
Note that both i386 and amd64 exclude the page from phys_avail[]
array, so this change is redundant, but I think that phys_avail[] on
UEFI-boot does not need to do that. Eventually the blacklisting
should be made conditional on CPUs which report that they are not
vulnerable to L1TF.
Reviewed by: emaste. jhb
Sponsored by: The FreeBSD Foundation
curpmap.
When performing context switch on a machine without PCID, if current
%cr3 equals to the new pmap %cr3, which is typical for kernel_pmap
vs. kernel process, I overlooked to update PCPU curpmap value. Remove
check for %cr3 not equal to pm_cr3 for doing the update. It is
believed that this case cannot happen at all, due to other changes in
this revision.
Also, do not set the very first curpmap to kernel_pmap, it should be
vmspace0 pmap instead to match curproc.
Move the common code to activate the initial pmap both on BSP and APs
into pmap_activate_boot() helper.
Reported by: eadler, ambrisko
Discussed with: kevans
Reviewed by: alc, markj (previous version)
Tested by: ambrisko (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D16618
Rather than hard-coding the number of CPUs to 2, look up the PVPE field
in MVPConf0, as the valid VPE numbers are from 0 to PVPE inclusive.
Submitted by: "James Clarke" <jrtc4@cam.ac.uk>
Reviewed by: br
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D16644
At some point memcpy() may be an ifunc, ifunc resolution cannot be done
until CPU identification has been performed, and CPU identification must
be done after loading any microcode updates.
X-MFC with: r337715
Sponsored by: The FreeBSD Foundation
it read-only instead of just failing if the media is write-protected.
The /net doesn't seem to require the flag.
MFC after: 2 weeks
Relnotes: yes
Sponsored by: DARPA, AFRL
after opening the console, replacing init as PID 1.
From the user point of view, it makes it possible to run eg the
shell as PID 1, using 'set init_exec=/bin/sh' at the loader(8)
prompt.
Reviewed by: kib
MFC after: 2 weeks
Relnotes: yes
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D16625
Trap reads to the arm64 ID registers and write a safe value into them. This
will allow us to put more useful values in these later and have userland
check them to find what features the hardware supports.
These are currently safe defaults, but will later be populated with better
values from the hardware.
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D16533
