Unmapped mbufs allow sendfile to carry multiple pages of data in a
single mbuf, without mapping those pages. It is a requirement for
Netflix's in-kernel TLS, and provides a 5-10% CPU savings on heavy web
serving workloads when used by sendfile, due to effectively
compressing socket buffers by an order of magnitude, and hence
reducing cache misses.
For this new external mbuf buffer type (EXT_PGS), the ext_buf pointer
now points to a struct mbuf_ext_pgs structure instead of a data
buffer. This structure contains an array of physical addresses (this
reduces cache misses compared to an earlier version that stored an
array of vm_page_t pointers). It also stores additional fields needed
for in-kernel TLS such as the TLS header and trailer data that are
currently unused. To more easily detect these mbufs, the M_NOMAP flag
is set in m_flags in addition to M_EXT.
Various functions like m_copydata() have been updated to safely access
packet contents (using uiomove_fromphys()), to make things like BPF
safe.
NIC drivers advertise support for unmapped mbufs on transmit via a new
IFCAP_NOMAP capability. This capability can be toggled via the new
'nomap' and '-nomap' ifconfig(8) commands. For NIC drivers that only
transmit packet contents via DMA and use bus_dma, adding the
capability to if_capabilities and if_capenable should be all that is
required.
If a NIC does not support unmapped mbufs, they are converted to a
chain of mapped mbufs (using sf_bufs to provide the mapping) in
ip_output or ip6_output. If an unmapped mbuf requires software
checksums, it is also converted to a chain of mapped mbufs before
computing the checksum.
Submitted by: gallatin (earlier version)
Reviewed by: gallatin, hselasky, rrs
Discussed with: ae, kp (firewalls)
Relnotes: yes
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20616
instead of a linear array.
The multicast memberships for the inpcb structure are protected by a
non-sleepable lock, INP_WLOCK(), which needs to be dropped when
calling the underlying possibly sleeping if_ioctl() method. When using
a linear array to keep track of multicast memberships, the computed
memory location of the multicast filter may suddenly change, due to
concurrent insertion or removal of elements in the linear array. This
in turn leads to various invalid memory access issues and kernel
panics.
To avoid this problem, put all multicast memberships on a STAILQ based
list. Then the memory location of the IPv4 and IPv6 multicast filters
become fixed during their lifetime and use after free and memory leak
issues are easier to track, for example by: vmstat -m | grep multi
All list manipulation has been factored into inline functions
including some macros, to easily allow for a future hash-list
implementation, if needed.
This patch has been tested by pho@ .
Differential Revision: https://reviews.freebsd.org/D20080
Reviewed by: markj @
MFC after: 1 week
Sponsored by: Mellanox Technologies
With this opcode it is possible to match TCP packets with specified
MSS option, whose value corresponds to configured in opcode value.
It is allowed to specify single value, range of values, or array of
specific values or ranges. E.g.
# ipfw add deny log tcp from any to any tcpmss 0-500
Reviewed by: melifaro,bcr
Obtained from: Yandex LLC
MFC after: 1 week
Sponsored by: Yandex LLC
If we take the slow path for forwarding we should still tell our
firewalls (hooked through pfil(9)) that we're forwarding. Pass the
ip_output() flags to ip_output_pfil() so it can set the PFIL_FWD flag
when we're forwarding.
MFC after: 1 week
Sponsored by: Axiado
in response to SACKs. The default behavior is unchanged; however, the limit
can be activated by changing the new net.inet.tcp.rack.split_limit sysctl.
Submitted by: Peter Lei <peterlei@netflix.com>
Reported by: jtl
Reviewed by: lstewart (earlier version)
Security: CVE-2019-5599
rename the source to gsb_crc32.c.
This is a prerequisite of unifying kernel zlib instances.
PR: 229763
Submitted by: Yoshihiro Ota <ota at j.email.ne.jp>
Differential Revision: https://reviews.freebsd.org/D20193
Apply a linker script when linking i386 kernel modules to apply padding
to a set_pcpu or set_vnet section. The padding value is kind-of random
and is used to catch modules not compiled with the linker-script, so
possibly still having problems leading to kernel panics.
This is needed as the code generated on certain architectures for
non-simple-types, e.g., an array can generate an absolute relocation
on the edge (just outside) the section and thus will not be properly
relocated. Adding the padding to the end of the section will ensure
that even absolute relocations of complex types will be inside the
section, if they are the last object in there and hence relocation will
work properly and avoid panics such as observed with carp.ko or ipsec.ko.
There is a rather lengthy discussion of various options to apply in
the mentioned PRs and their depends/blocks, and the review.
There seems no best solution working across multiple toolchains and
multiple version of them, so I took the liberty of taking one,
as currently our users (and our CI system) are hitting this on
just i386 and we need some solution. I wish we would have a proper
fix rather than another "hack".
Also backout r340009 which manually, temporarily fixed CARP before 12.0-R
"by chance" after a lead-up of various other link-elf.c and related fixes.
PR: 230857,238012
With suggestions from: arichardson (originally last year)
Tested by: lwhsu
Event: Waterloo Hackathon 2019
Reported by: lwhsu, olivier
MFC after: 6 weeks
Differential Revision: https://reviews.freebsd.org/D17512
The corresponding changes for the RACK stack where missed and are added
by this commit.
Reviewed by: Richard Scheffenegger, rrs@
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D20372
another one in udp_output(). This one is a race condition.
We do check on the laddr and lport without holding a lock in
order to determine whether we want a read or a write lock
(this is in the "sendto/sendmsg" cases where addr (sin) is given).
Instrumenting the kernel showed that after taking the lock, we
had bound to a local port from a parallel thread on the same socket.
If we find that case, unlock, and retry again. Taking the write
lock would not be a problem in first place (apart from killing some
parallelism). However the retry is needed as later on based on
similar condition checks we do acquire the pcbinfo lock and if the
conditions have changed, we might find ourselves with a lock
inconsistency, hence at the end of the function when trying to
unlock, hitting the KASSERT.
Reported by: syzbot+bdf4caa36f3ceeac198f@syzkaller.appspotmail.com
Reviewed by: markj
MFC after: 6 weeks
Event: Waterloo Hackathon 2019
netdump waits for acknowledgement from the server for each write. When
dumping page table pages, we perform many small writes, limiting
throughput. Use the netdump client's buffer to buffer small contiguous
writes before calling netdump_send() to flush the MAXDUMPPGS-sized
buffer. This results in a significant reduction in the time taken to
complete a netdump.
Submitted by: Sam Gwydir <sam@samgwydir.com>
Reviewed by: cem
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D20317
received and support for time stamps was negotiated in the SYN/SYNACK
exchange, perform the PAWS check and only expand the syn cache entry if
the check is passed.
Without this check, endpoints may get stuck on the incomplete queue.
Reviewed by: jtl@
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D20374
- Perform ifp mismatch checks (to determine if a send tag is allocated
for a different ifp than the one the packet is being output on), in
ip_output() and ip6_output(). This avoids sending packets with send
tags to ifnet drivers that don't support send tags.
Since we are now checking for ifp mismatches before invoking
if_output, we can now try to allocate a new tag before invoking
if_output sending the original packet on the new tag if allocation
succeeds.
To avoid code duplication for the fragment and unfragmented cases,
add ip_output_send() and ip6_output_send() as wrappers around
if_output and nd6_output_ifp, respectively. All of the logic for
setting send tags and dealing with send tag-related errors is done
in these wrapper functions.
For pseudo interfaces that wrap other network interfaces (vlan and
lagg), wrapper send tags are now allocated so that ip*_output see
the wrapper ifp as the ifp in the send tag. The if_transmit
routines rewrite the send tags after performing an ifp mismatch
check. If an ifp mismatch is detected, the transmit routines fail
with EAGAIN.
- To provide clearer life cycle management of send tags, especially
in the presence of vlan and lagg wrapper tags, add a reference count
to send tags managed via m_snd_tag_ref() and m_snd_tag_rele().
Provide a helper function (m_snd_tag_init()) for use by drivers
supporting send tags. m_snd_tag_init() takes care of the if_ref
on the ifp meaning that code alloating send tags via if_snd_tag_alloc
no longer has to manage that manually. Similarly, m_snd_tag_rele
drops the refcount on the ifp after invoking if_snd_tag_free when
the last reference to a send tag is dropped.
This also closes use after free races if there are pending packets in
driver tx rings after the socket is closed (e.g. from tcpdrop).
In order for m_free to work reliably, add a new CSUM_SND_TAG flag in
csum_flags to indicate 'snd_tag' is set (rather than 'rcvif').
Drivers now also check this flag instead of checking snd_tag against
NULL. This avoids false positive matches when a forwarded packet
has a non-NULL rcvif that was treated as a send tag.
- cxgbe was relying on snd_tag_free being called when the inp was
detached so that it could kick the firmware to flush any pending
work on the flow. This is because the driver doesn't require ACK
messages from the firmware for every request, but instead does a
kind of manual interrupt coalescing by only setting a flag to
request a completion on a subset of requests. If all of the
in-flight requests don't have the flag when the tag is detached from
the inp, the flow might never return the credits. The current
snd_tag_free command issues a flush command to force the credits to
return. However, the credit return is what also frees the mbufs,
and since those mbufs now hold references on the tag, this meant
that snd_tag_free would never be called.
To fix, explicitly drop the mbuf's reference on the snd tag when the
mbuf is queued in the firmware work queue. This means that once the
inp's reference on the tag goes away and all in-flight mbufs have
been queued to the firmware, tag's refcount will drop to zero and
snd_tag_free will kick in and send the flush request. Note that we
need to avoid doing this in the middle of ethofld_tx(), so the
driver grabs a temporary reference on the tag around that loop to
defer the free to the end of the function in case it sends the last
mbuf to the queue after the inp has dropped its reference on the
tag.
- mlx5 preallocates send tags and was using the ifp pointer even when
the send tag wasn't in use. Explicitly use the ifp from other data
structures instead.
- Sprinkle some assertions in various places to assert that received
packets don't have a send tag, and that other places that overwrite
rcvif (e.g. 802.11 transmit) don't clobber a send tag pointer.
Reviewed by: gallatin, hselasky, rgrimes, ae
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20117
that we end up in a consistent locking state at the end of
udp_output() in order to be able to see what the values are based
on which we once took a decision (note: some values may have changed).
This helped to debug a syzkaller report.
MFC after: 2 months
Event: Waterloo Hackathon 2019
These are obviously missing from the .c files, but don't show up in any
tinderbox configuration (due to latent header pollution of some kind). It
seems some configurations don't have this pollution, and the includes are
obviously missing, so go ahead and add them.
Reported by: Peter Jeremy <peter AT rulingia.com>
X-MFC-With: r347984
This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces header
pollution substantially.
EVENTHANDLER_DECLARE and EVENTHANDLER_LIST_DECLAREs were moved out of .c
files into appropriate headers (e.g., sys/proc.h, powernv/opal.h).
As a side effect of reduced header pollution, many .c files and headers no
longer contain needed definitions. The remainder of the patch addresses
adding appropriate includes to fix those files.
LOCK_DEBUG and LOCK_FILE_LINE_ARG are moved to sys/_lock.h, as required by
sys/mutex.h since r326106 (but silently protected by header pollution prior
to this change).
No functional change (intended). Of course, any out of tree modules that
relied on header pollution for sys/eventhandler.h, sys/lock.h, or
sys/mutex.h inclusion need to be fixed. __FreeBSD_version has been bumped.
r333175 converted the global multicast lock to a sleepable sx lock,
so the lock order with respect to the (non-sleepable) inp lock changed.
To handle this, r333175 and r333505 added code to drop the inp lock,
but this opened races that could leave multicast group description
structures in an inconsistent state. This change fixes the problem by
simply acquiring the global lock sooner. Along the way, this fixes
some LORs and bogus error handling introduced in r333175, and commits
some related cleanup.
Reported by: syzbot+ba7c4943547e0604faca@syzkaller.appspotmail.com
Reported by: syzbot+1b803796ab94d11a46f9@syzkaller.appspotmail.com
Reviewed by: ae
MFC after: 3 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D20070
Boot-time netdump configuration is much more useful if one can configure the
client and gateway addresses. Fix trivial typo.
(Long-standing bug, I believe it dates to the original netdump commit.)
Spotted by: one of vangyzen@ or markj@
Sponsored by: Dell EMC Isilon
Prior to this revision, struct diocskerneldump_arg (and struct netdump_conf
with embedded diocskerneldump_arg before r347192), were copied in their
entirety to the global 'nd_conf' variable. Also prior to this revision,
de-configuring netdump would *not* remove the the key material from global
nd_conf.
As part of Encrypted Kernel Crash Dumps (EKCD), which was developed
contemporaneously with netdump but happened to land first, the
diocskerneldump_arg structure will contain sensitive key material
(kda_key[]) when encrypted dumps are configured.
Netdump doesn't have any use for the key data -- encryption is handled in
the core dumper code -- so in this revision, we no longer store it.
Unfortunately, I think this leak dates to the initial import of netdump in
r333283; so it's present in FreeBSD 12.0.
Fortunately, the impact *seems* relatively minor. Any new *netdump*
configuration would overwrite the key material; for active encrypted netdump
configurations, the key data stored was just a duplicate of the key material
already in the core dumper code; and no user interface (other than
/dev/kmem) actually exposed the leaked material to userspace.
Reviewed by: markj, rpokala (earlier commit message)
MFC after: 2 weeks
Security: yes (minor)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D20233
Bind the TCP pacer threads to NUMA domains and build per-domain
pacer-thread lookup tables. These tables allow us to use the
inpcb's NUMA domain information to match an inpcb with a pacer
thread on the same domain.
The motivation for this is to keep the TCP connection local to a
NUMA domain as much as possible.
Thanks to jhb for pre-reviewing an earlier version of the patch.
Reviewed by: rrs
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20134
This adds initial support for RFC 2883.
Submitted by: Richard Scheffenegger
Reviewed by: rrs@
Differential Revision: https://reviews.freebsd.org/D19334
This is descrined in RFC 6582, which updates RFC 3782.
Submitted by: Richard Scheffenegger
Reviewed by: lstewart@
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D17614
lookup KPI in ip_output() like it is already used in ip_forward().
However, when there is no PCB provided we can use fast KPI, gaining
performance advantage.
Typical case when ip_output() is called without a PCB pointer is a
sendto(2) on a not connected UDP socket. In practice DNS servers do
this.
Reviewed by: melifaro
Differential Revision: https://reviews.freebsd.org/D19804
Allow users to specify multiple dump configurations in a prioritized list.
This enables fallback to secondary device(s) if primary dump fails. E.g.,
one might configure a preference for netdump, but fallback to disk dump as a
second choice if netdump is unavailable.
This change does not list-ify netdump configuration, which is tracked
separately from ordinary disk dumps internally; only one netdump
configuration can be made at a time, for now. It also does not implement
IPv6 netdump.
savecore(8) is already capable of scanning and iterating multiple devices
from /etc/fstab or passed on the command line.
This change doesn't update the rc or loader variables 'dumpdev' in any way;
it can still be set to configure a single dump device, and rc.d/savecore
still uses it as a single device. Only dumpon(8) is updated to be able to
configure the more complicated configurations for now.
As part of revving the ABI, unify netdump and disk dump configuration ioctl
/ structure, and leave room for ipv6 netdump as a future possibility.
Backwards-compatibility ioctls are added to smooth ABI transition,
especially for developers who may not keep kernel and userspace perfectly
synced.
Reviewed by: markj, scottl (earlier version)
Relnotes: maybe
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D19996
Turning on multicast debug made multicast failure worse
because the strings and #define values no longer matched
up. Fix them, and make sure they stay matched-up.
Submitted by: torek
MFC after: 1 week
Sponsored by: iXsystems, Inc.
Drivers can now pass up numa domain information via the
mbuf numa domain field. This information is then used
by TCP syncache_socket() to associate that information
with the inpcb. The domain information is then fed back
into transmitted mbufs in ip{6}_output(). This mechanism
is nearly identical to what is done to track RSS hash values
in the inp_flowid.
Follow on changes will use this information for lacp egress
port selection, binding TCP pacers to the appropriate NUMA
domain, etc.
Reviewed by: markj, kib, slavash, bz, scottl, jtl, tuexen
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20028
This GRE-in-UDP encapsulation allows the UDP source port field to be
used as an entropy field for load-balancing of GRE traffic in transit
networks. Also most of multiqueue network cards are able distribute
incoming UDP datagrams to different NIC queues, while very little are
able do this for GRE packets.
When an administrator enables UDP encapsulation with command
`ifconfig gre0 udpencap`, the driver creates kernel socket, that binds
to tunnel source address and after udp_set_kernel_tunneling() starts
receiving of all UDP packets destined to 4754 port. Each kernel socket
maintains list of tunnels with different destination addresses. Thus
when several tunnels use the same source address, they all handled by
single socket. The IP[V6]_BINDANY socket option is used to be able bind
socket to source address even if it is not yet available in the system.
This may happen on system boot, when gre(4) interface is created before
source address become available. The encapsulation and sending of packets
is done directly from gre(4) into ip[6]_output() without using sockets.
Reviewed by: eugen
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D19921
In r297225 the initial INP_RLOCK() was replaced by an early
acquisition of an r- or w-lock depending on input variables
possibly extending the write locked area for reasons not entirely
clear but possibly to avoid a later case of unlock and relock
leading to a possible race condition and possibly in order to
allow the route cache to work for connected sockets.
Unfortunately the conditions were not 1:1 replicated (probably
because of the route cache needs). While this would not be a
problem the legacy IP code compared to IPv6 has an extra case
when dealing with IP_SENDSRCADDR. In a particular case we were
holding an exclusive inp lock and acquired the shared udbinfo
lock (now epoch).
When then running into an error case, the locking assertions
on release fired as the udpinfo and inp lock levels did not match.
Break up the special case and in that particular case acquire
and udpinfo lock depending on the exclusitivity of the inp lock.
MFC After: 9 days
Reported-by: syzbot+1f5c6800e4f99bdb1a48@syzkaller.appspotmail.com
Reviewed by: tuexen
Differential Revision: https://reviews.freebsd.org/D19594
fragmented packets.
When sending IPv4 and IPv6 fragmented packets and a fragment is lost,
the mbuf making up the fragment will remain in the temporary hashed
fragment list for a while. If the network interface departs before the
so-called slow timeout clears the packet, the fragment causes a panic
when the timeout kicks in due to accessing a freed network interface
structure.
Make sure that when a network device is departing, all hashed IPv4 and
IPv6 fragments belonging to it, get freed.
Backtrace:
panic()
icmp6_reflect()
hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
^^^^ rcvif->if_afdata[AF_INET6] is NULL.
icmp6_error()
frag6_freef()
frag6_slowtimo()
pfslowtimo()
softclock_call_cc()
softclock()
ithread_loop()
Differential Revision: https://reviews.freebsd.org/D19622
Reviewed by: bz (network), adrian
MFC after: 1 week
Sponsored by: Mellanox Technologies
The logic was present for the 11 version of the DIOCSKERNELDUMP ioctl, but
had not been updated for the 12 ABI.
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D19980
The inp lock is not needed for testing the V6 flag as that flag is set
once when the inp is created and never changes. For non-TCP socket
options the lock is immediately dropped after checking that flag.
This just pushes the lock down to only be acquired for TCP socket
options.
This isn't a hot-path, more a cosmetic cleanup I noticed while reading
the code.
Reviewed by: bz
MFC after: 1 month
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D19740
ensure that the ip_hl field is valid. Furthermore, ensure that the complete
IPv4 header is contained in the first mbuf. Finally, move the length checks
before relying on them when accessing fields of the IPv4 header.
Reported by: jtl@
Reviewed by: jtl@
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D19181
When leaving a multicast group, a hole may be created in the inpcb's
source filter and group membership arrays. To remove the hole, the
succeeding array elements are copied over by one entry. The multicast
code expects that a newly allocated array element is initialized, but
the code which shifts a tail of the array was leaving stale data
in the final entry. Fix this by explicitly reinitializing the last
entry following such a copy.
Reported by: syzbot+f8c3c564ee21d650475e@syzkaller.appspotmail.com
Reviewed by: ae
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19872
was unlocked and yet the bucket-unlock flag was not
changed to false. This can cause a panic if INVARIANTS
is on and we go through the right path (though rare).
This fixes the correct bug :)
Reported by: syzbot+179a1ad49f3c4c215fa2@syzkaller.appspotmail.com
Reviewed by: tuexen@
There are a few places that use hand crafted versions of the macros
from sys/netinet/in.h making it difficult to actually alter the
values in use by these macros. Correct that by replacing handcrafted
code with proper macro usage.
Reviewed by: karels, kristof
Approved by: bde (mentor)
MFC after: 3 weeks
Sponsored by: John Gilmore
Differential Revision: https://reviews.freebsd.org/D19317
was unlocked and yet the bucket-unlock flag was not
changed to false. This can cause a panic if INVARIANTS
is on and we go through the right path (though rare).
Reported by: syzbot+179a1ad49f3c4c215fa2@syzkaller.appspotmail.com
Reviewed by: tuexen@
MFC after: 1 week
SCTP_SENDALL flag. Allow also only one operation per SCTP endpoint.
This fixes an issue found by running syzkaller and is joint work with rrs@.
MFC after: 1 week
CLAT is customer-side translator that algorithmically translates 1:1
private IPv4 addresses to global IPv6 addresses, and vice versa.
It is implemented as part of ipfw_nat64 kernel module. When module
is loaded or compiled into the kernel, it registers "nat64clat" external
action. External action named instance can be created using `create`
command and then used in ipfw rules. The create command accepts two
IPv6 prefixes `plat_prefix` and `clat_prefix`. If plat_prefix is ommitted,
IPv6 NAT64 Well-Known prefix 64:ff9b::/96 will be used.
# ipfw nat64clat CLAT create clat_prefix SRC_PFX plat_prefix DST_PFX
# ipfw add nat64clat CLAT ip4 from IPv4_PFX to any out
# ipfw add nat64clat CLAT ip6 from DST_PFX to SRC_PFX in
Obtained from: Yandex LLC
Submitted by: Boris N. Lytochkin
MFC after: 1 month
Relnotes: yes
Sponsored by: Yandex LLC
r344504 added an extra ARP_LOG() call in case of an if_output() failure.
It turns out IPv4 can be noisy. In order to not spam the console by default:
(a) add a counter for these events so people can keep better track of how
often it happens, and
(b) add a sysctl to select the default ARP_LOG log level and set it to
INFO avoiding the one (the new) DEBUG level by default.
Claim a spare (1st one after 10 years since the stats were added) in order
to not break netstat from FreeBSD 12->13 updates in the future.
Reviewed by: karels
Differential Revision: https://reviews.freebsd.org/D19490
level socket option SCTP_GET_LOCAL_ADDRESSES in a getsockopt() call.
Thanks to Thomas Barabosch for reporting the issue which was found by
running syzkaller.
MFC after: 3 days
- Use strlcpy() with sizeof() instead of strncpy().
- Simplify initialization of TCP functions structures.
init_tcp_functions() was already called before the first call to
register a stack. Just inline the work in the SYSINIT and remove
the racy helper variable. Instead, KASSERT that the rw lock is
initialized when registering a stack.
- Protect the default stack via a direct pointer comparison.
The default stack uses the name "freebsd" instead of "default" so
this protection wasn't working for the default stack anyway.
Reviewed by: rrs
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D19152
arprequest() is a void function and in case of error we simply
return without any feedback. In case of any local operation
or *if_output() failing no feedback is send up the stack for the
packet which triggered the arp request to be sent.
arpresolve_full() has three pre-canned possible errors returned
(if we have not yet sent enough arp requests or if we tried
often enough without success) otherwise "no error" is returned.
Make arprequest() an "internal" function arprequest_internal() which
does return a possible error to the caller. Preserve arprequest()
as a void wrapper function for external consumers.
In arpresolve_full() add an extra error checking. Use the
arprequest_internal() function and only return an error if non
of the three ones (mentioend above) are already set.
This will return possible errors all the way up the stack and
allows functions and programs to react on the send errors rather
than leaving them in the dark. Also they might get more detailed
feedback of why packets cannot be sent and they will receive it
quicker.
Reviewed by: karels, hselasky
Differential Revision: https://reviews.freebsd.org/D18904
for struct ip_mreq remains in place.
The struct ip_mreqn is Linux extension to classic BSD multicast API. It
has extra field allowing to specify the interface index explicitly. In
Linux it used as argument for IP_MULTICAST_IF and IP_ADD_MEMBERSHIP.
FreeBSD kernel also declares this structure and supports it as argument
to IP_MULTICAST_IF since r170613. So, we have structure declared but
not fully supported, this confused third party application configure
scripts.
Code handling IP_ADD_MEMBERSHIP was mixed together with code for
IP_ADD_SOURCE_MEMBERSHIP. Bringing legacy and new structure support
into the mess would made the "argument switcharoo" intolerable, so
code was separated into its own switch case clause.
MFC after: 3 months
Differential Revision: https://reviews.freebsd.org/D19276
is acceptable in the congestion avoidance phase, but not during slow start.
The MTU is is also not taken into account.
Use a method instead, which is based on exponential growth working also in
slow start and being independent from the MTU.
This is joint work with rrs@.
Reviewed by: rrs@, Richard Scheffenegger
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D18375
When TCP_REASS_LOGGING is defined, a NULL pointer dereference would happen,
if user data was received during the TCP handshake and BB logging is used.
A KASSERT is also added to detect tcp_reass() calls with illegal parameter
combinations.
Reported by: bz@
Reviewed by: rrs@
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D19254
1 second as allowed by RFC 6298.
Reviewed by: kbowling@, Richard Scheffenegger
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D18941
But ipsec_delete_pcbpolicy() uses some VNET-virtualized variables,
and thus it needs VNET context, that is missing during gtaskqueue
executing. Use inp_vnet context to set curvnet in in_pcbfree_deferred().
PR: 235684
MFC after: 1 week
Gratuitous ARP packets are sent from a timer, which means we don't have a vnet
context set. As a result we panic trying to send the packet.
Set the vnet context based on the interface associated with the interface
address.
To reproduce:
sysctl net.link.ether.inet.garp_rexmit_count=2
ifconfig vtnet1 10.0.0.1/24 up
PR: 235699
Reviewed by: vangyzen@
MFC after: 1 week
option.
This issue was found by running syzkaller on OpenBSD.
Greg Steuck made me aware that the problem might also exist on FreeBSD.
Reported by: Greg Steuck
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D18834
sysctl variable net.inet.tcp.cc.cdg.smoothing_factor to 0, the smoothing
is disabled. Without this patch, a division by zero orrurs.
PR: 193762
Reviewed by: lstewart@, rrs@
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D19071
Use recent best practices for Copyright form at the top of
the license:
1. Remove all the All Rights Reserved clauses on our stuff. Where we
piggybacked others, use a separate line to make things clear.
2. Use "Netflix, Inc." everywhere.
3. Use a single line for the copyright for grep friendliness.
4. Use date ranges in all places for our stuff.
Approved by: Netflix Legal (who gave me the form), adrian@ (pmc files)
consistently.
This inconsistency was observed when working on the bug reported in
PR 235256, although it does not fix the reported issue. The fix for
the PR will be a separate commit.
PR: 235256
Reviewed by: rrs@, Richard Scheffenegger
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D19033
The KPI have been reviewed and cleansed of features that were planned
back 20 years ago and never implemented. The pfil(9) internals have
been made opaque to protocols with only returned types and function
declarations exposed. The KPI is made more strict, but at the same time
more extensible, as kernel uses same command structures that userland
ioctl uses.
In nutshell [KA]PI is about declaring filtering points, declaring
filters and linking and unlinking them together.
New [KA]PI makes it possible to reconfigure pfil(9) configuration:
change order of hooks, rehook filter from one filtering point to a
different one, disconnect a hook on output leaving it on input only,
prepend/append a filter to existing list of filters.
Now it possible for a single packet filter to provide multiple rulesets
that may be linked to different points. Think of per-interface ACLs in
Cisco or Juniper. None of existing packet filters yet support that,
however limited usage is already possible, e.g. default ruleset can
be moved to single interface, as soon as interface would pride their
filtering points.
Another future feature is possiblity to create pfil heads, that provide
not an mbuf pointer but just a memory pointer with length. That would
allow filtering at very early stages of a packet lifecycle, e.g. when
packet has just been received by a NIC and no mbuf was yet allocated.
Differential Revision: https://reviews.freebsd.org/D18951
SIFTR does not allow any kind of filtering, but captures every packet
processed by the TCP stack.
Often, only a specific session or service is of interest, and doing the
filtering in post-processing of the log adds to the overhead of SIFTR.
This adds a new sysctl net.inet.siftr.port_filter. When set to zero, all
packets get captured as previously. If set to any other value, only
packets where either the source or the destination ports match, are
captured in the log file.
Submitted by: Richard Scheffenegger
Reviewed by: Cheng Cui
Differential Revision: https://reviews.freebsd.org/D18897
RFC 3168 defines an ECN-setup SYN-ACK packet as on with the ECE flags
set and the CWR flags not set. The code was only checking if ECE flag
is set. This patch adds the check to verify that the CWR flags is not
set.
Submitted by: Richard Scheffenegger
Reviewed by: tuexen@
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D18996
This allows the part of the rewrite of TCP reassembly in this
files to be MFCed to stable/11 with manual change.
MFC after: 3 days
Sponsored by: Netflix, Inc.
When implementing support for IW10, an update in the computation
of the restart window used after an idle phase was missed. To
minimize code duplication, implement the logic in tcp_compute_initwnd()
and call it. This fixes a bug in NewReno, which was not aware of
IW10.
Submitted by: Richard Scheffenegger
Reviewed by: tuexen@
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D18940
After the afdata read lock was converted to epoch(9), readers could
observe a linked LLE and block on the LLE while a thread was
unlinking the LLE. The writer would then release the lock and schedule
the LLE for deferred free, allowing readers to continue and potentially
schedule the LLE timer. By the point the timer fires, the structure is
freed, typically resulting in a crash in the callout subsystem.
Fix the problem by modifying the lookup path to check for the LLE_LINKED
flag upon acquiring the LLE lock. If it's not set, the lookup fails.
PR: 234296
Reviewed by: bz
Tested by: sbruno, Victor <chernov_victor@list.ru>,
Mike Andrews <mandrews@bit0.com>
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18906
Correct a logic error.
Only disable when already enabled or enable when disabled.
Submitted by: Richard Scheffenegger
Reviewed by: Cheng Cui
Obtained from: Cheng Cui
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D18885
When the TCP window scale option is not used, and the window
opens up enough in one soreceive, a window update will not be sent.
For example, if recwin == 65535, so->so_rcv.sb_hiwat >= 262144, and
so->so_rcv.sb_hiwat <= 524272, the window update will never be sent.
This is because recwin and adv are clamped to TCP_MAXWIN << tp->rcv_scale,
and so will never be >= so->so_rcv.sb_hiwat / 4
or <= so->so_rcv.sb_hiwat / 8.
This patch ensures a window update is sent if the window opens by
TCP_MAXWIN << tp->rcv_scale, which should only happen when the window
size goes from zero to the max expressible.
This issue looks like it was introduced in r306769 when recwin was clamped
to TCP_MAXWIN << tp->rcv_scale.
MFC after: 1 week
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D18821
r336616 copies inp->inp_options using the m_dup() function.
However, this function expects an mbuf packet header at the beginning,
which is not true in this case.
Therefore, use m_copym() instead of m_dup().
This issue was found by syzkaller.
Reviewed by: mmacy@
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D18753
- Remove macros that covertly create epoch_tracker on thread stack. Such
macros a quite unsafe, e.g. will produce a buggy code if same macro is
used in embedded scopes. Explicitly declare epoch_tracker always.
- Unmask interface list IFNET_RLOCK_NOSLEEP(), interface address list
IF_ADDR_RLOCK() and interface AF specific data IF_AFDATA_RLOCK() read
locking macros to what they actually are - the net_epoch.
Keeping them as is is very misleading. They all are named FOO_RLOCK(),
while they no longer have lock semantics. Now they allow recursion and
what's more important they now no longer guarantee protection against
their companion WLOCK macros.
Note: INP_HASH_RLOCK() has same problems, but not touched by this commit.
This is non functional mechanical change. The only functionally changed
functions are ni6_addrs() and ni6_store_addrs(), where we no longer enter
epoch recursively.
Discussed with: jtl, gallatin
As it does for recv*(2), MSG_DONTWAIT indicates that the call should
not block, returning EAGAIN instead. Linux and OpenBSD both implement
this, so the change makes porting easier, especially since we do not
return EINVAL or so when unrecognized flags are specified.
Submitted by: Greg V <greg@unrelenting.technology>
Reviewed by: tuexen
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D18728
When receiving TCP segments the stack protects itself by limiting
the resources allocated for a TCP connections. This patch adds
an exception to these limitations for the TCP segement which is the next
expected in-sequence segment. Without this patch, TCP connections
may stall and finally fail in some cases of packet loss.
Reported by: jhb@
Reviewed by: jtl@, rrs@
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D18580
This change is causing TCP connections using cubic to hang. Need to dig more to
find exact cause and fix it.
Reported by: tj at mrsk dot me, Matt Garber (via twitter)
Discussed with: sbruno (previously), allanjude, cperciva
MFC after: 3 days
Use the sysctl_handle_int() handler to write out the old value and read
the new value into a temporary variable. Use the temporary variable
for any checks of values rather than using the CAST_PTR_INT() macro on
req->newptr. The prior usage read directly from userspace memory if the
sysctl() was called correctly. This is unsafe and doesn't work at all on
some architectures (at least i386.)
In some cases, the code could also be tricked into reading from kernel
memory and leaking limited information about the contents or crashing
the system. This was true for CDG, newreno, and siftr on all platforms
and true for i386 in all cases. The impact of this bug is largest in
VIMAGE jails which have been configured to allow writing to these
sysctls.
Per discussion with the security officer, we will not be issuing an
advisory for this issue as root access and a non-default config are
required to be impacted.
Reviewed by: markj, bz
Discussed with: gordon (security officer)
MFC after: 3 days
Security: kernel information leak, local DoS (both require root)
Differential Revision: https://reviews.freebsd.org/D18443
Memory beyond that limit was previously unused, wasting roughly 1MB per
8GB of RAM. Also retire INP_PCBLBGROUP_PORTHASH, which was identical to
INP_PCBPORTHASH.
Reviewed by: glebius
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D17803
This can be useful, when net.inet.ip.fw.dyn_keep_states is enabled, but
after rules reloading some state must be deleted. Added new flag '-D'
for such purpose.
Retire '-e' flag, since there can not be expired states in the meaning
that this flag historically had.
Also add "verbose" mode for listing of dynamic states, it can be enabled
with '-v' flag and adds additional information to states list. This can
be useful for debugging.
Obtained from: Yandex LLC
MFC after: 2 months
Sponsored by: Yandex LLC
Limiting the length to 2048 bytes seems to be acceptable, since
the values used right now are using 8 bytes.
Reviewed by: glebius, bz, rrs
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D18366
Various network protocol sysctl handlers were not zero-filling their
output buffers and thus would export uninitialized stack memory to
userland. Fix a number of such handlers.
Reported by: Thomas Barabosch, Fraunhofer FKIE
Reviewed by: tuexen
MFC after: 3 days
Security: kernel memory disclosure
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18301
segment in the SYN-SENT state as stated in Section 3.9 of RFC 793,
page 66. Ensure this is also done by the TCP RACK stack.
Reviewed by: rrs@
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D18034
the TCP connection was initiated using the RACK stack, but the
peer does not support the TCP RACK extension.
This ensures that the TCP behaviour on the wire is the same if
the TCP connection is initated using the RACK stack or the default
stack.
Reviewed by: rrs@
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D18032
zero. This was already done when sending them via tcp_respond().
Reviewed by: rrs@
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D17949
There are two locations where an always true comparison was made in
a KASSERT. Replace this by an appropriate check and use a consistent
panic message. Also use this code when checking a similar condition.
PR: 229664
Reviewed by: rrs@
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D18021
Specifically, block 0-length fragments, even when the MF bit is clear.
Also, ensure that every fragment with the MF bit clear ends at the same
offset and that no subsequently-received fragments exceed that offset.
Reviewed by: glebius, markj
MFC after: 3 days
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D17922
Such fragments are obviously invalid, and when processed may end up
violating the sort order (by offset) of fragments of a given packet.
This doesn't appear to be exploitable, however.
Reviewed by: emaste
Discussed with: jtl
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17914
icmp_error allocates either an mbuf (with pkthdr) or a cluster depending
on the size of data to be quoted in the ICMP reply, but the calculation
failed to account for the additional padding that m_align may apply.
Include the ip header in the size passed to m_align. On 64-bit archs
this will have the net effect of moving everything 4 bytes later in the
mbuf or cluster. This will result in slightly pessimal alignment for
the ICMP data copy.
Also add an assertion that we do not move m_data before the beginning of
the mbuf or cluster.
Reported by: A reddit user
Reviewed by: bz, jtl
MFC after: 3 days
Security: CVE-2018-17156
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17909
This is a valid case for the userland stack, where this fixes
two set-but-not-used warnings in this case.
Thanks to Christian Wright for reporting the issue.
end of the vnet_set. The generated code uses an absolute relocation at
one byte beyond the end of the carpstats array. This means the relocation
for the vnet does not happen for carpstats initialisation and as a result
the kernel panics on module load.
This problem has only been observed with carp and only on i386.
We considered various possible solutions including using linker scripts
to add padding to all kernel modules for pcpu and vnet sections.
While the symbols (by chance) stay in the order of appearance in the file
adding an unused non-file-local variable at the end of the file will extend
the size of set_vnet and hence make the absolute relocation for carpstats
work (think of this as a single-module set_vnet padding).
This is a (tmporary) hack. It is the least intrusive one as we need a
timely solution for the upcoming release. We will revisit the problem in
HEAD. For a lot more information and the possible alternate solutions
please see the PR and the references therein.
PR: 230857
MFC after: 3 days
specification for the comparisons made.
Thanks to lstewart@ for the suggestion.
MFC after: 4 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D17595
This change defines the RA "6" (IPv6-Only) flag which routers
may advertise, kernel logic to check if all routers on a link
have the flag set and accordingly update a per-interface flag.
If all routers agree that it is an IPv6-only link, ether_output_frame(),
based on the interface flag, will filter out all ETHERTYPE_IP/ARP
frames, drop them, and return EAFNOSUPPORT to upper layers.
The change also updates ndp to show the "6" flag, ifconfig to
display the IPV6_ONLY nd6 flag if set, and rtadvd to allow
announcing the flag.
Further changes to tcpdump (contrib code) are availble and will
be upstreamed.
Tested the code (slightly earlier version) with 2 FreeBSD
IPv6 routers, a FreeBSD laptop on ethernet as well as wifi,
and with Win10 and OSX clients (which did not fall over with
the "6" flag set but not understood).
We may also want to (a) implement and RX filter, and (b) over
time enahnce user space to, say, stop dhclient from running
when the interface flag is set. Also we might want to start
IPv6 before IPv4 in the future.
All the code is hidden under the EXPERIMENTAL option and not
compiled by default as the draft is a work-in-progress and
we cannot rely on the fact that IANA will assign the bits
as requested by the draft and hence they may change.
Dear 6man, you have running code.
Discussed with: Bob Hinden, Brian E Carpenter
This change is similar to r339646. The callback that checks for appearing
and disappearing of tunnel ingress address can be called during VNET
teardown. To prevent access to already freed memory, add check to the
callback and epoch_wait() call to be sure that callback has finished its
work.
MFC after: 20 days
- Add a blank line before a block comment to match other block comments
in the same function.
- Sort the prototype for sbsndptr_adv and fix whitespace between return
type and function name.
Reviewed by: gallatin, bz
Differential Revision: https://reviews.freebsd.org/D17474
Currently, icmp_error() function copies FIB number from original packet
into generated ICMP response but not mbuf_tags(9) chain.
This prevents us from easily matching ICMP responses corresponding
to tagged original packets by means of packet filter such as ipfw(8).
For example, ICMP "time-exceeded in-transit" packets usually generated
in response to traceroute probes lose tags attached to original packets.
This change adds new sysctl net.inet.icmp.error_keeptags
that defaults to 0 to avoid extra overhead when this feature not needed.
Set net.inet.icmp.error_keeptags=1 to make icmp_error() copy mbuf_tags
from original packet to generated ICMP response.
PR: 215874
MFC after: 1 month
* register handler for ingress address appearing/disappearing;
* add new srcaddr hash table for fast softc lookup by srcaddr;
* when srcaddr disappears, clear IFF_DRV_RUNNING flag from interface,
and set it otherwise;
MFC after: 1 month
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17214
* register handler for ingress address appearing/disappearing;
* add new srcaddr hash table for fast softc lookup by srcaddr;
* when srcaddr disappears, clear IFF_DRV_RUNNING flag from interface,
and set it otherwise;
* remove the note about ingress address from BUGS section.
MFC after: 1 month
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17134
appearing and disappearing on the host system.
Such handling is need, because tunneling interfaces must use addresses,
that are configured on the host as ingress addresses for tunnels.
Otherwise the system can send spoofed packets with source address, that
belongs to foreign host.
The KPI uses ifaddr_event_ext event to implement addresses tracking.
Tunneling interfaces register event handlers and then they are
notified by the kernel, when an address disappears or appears.
ifaddr_event_compat() handler from if.c replaced by srcaddr_change_event()
in the ip_encap.c
MFC after: 1 month
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17134
that was added using "new rule format". And then, when the kernel
returns rule with this flag, ipfw(8) can correctly show it.
Reported by: lev
MFC after: 3 weeks
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17373
handler receives the type of event IFADDR_EVENT_ADD/IFADDR_EVENT_DEL,
and the pointer to ifaddr. Also ifaddr_event now is implemented using
ifaddr_event_ext handler.
MFC after: 3 weeks
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17100
code paths. Both are not consistent and the one on the syn cache code
does not conform to the relevant specifications (Page 69 of RFC 793
and Section 4.2 of RFC 5961).
This patch fixes this:
* The sequence numbers checks are fixed as specified on
page Page 69 RFC 793.
* The sysctl variable net.inet.tcp.insecure_rst is now honoured
and the behaviour as specified in Section 4.2 of RFC 5961.
Approved by: re (gjb@)
Reviewed by: bz@, glebius@, rrs@,
Differential Revision: https://reviews.freebsd.org/D17595
Sponsored by: Netflix, Inc.
to this change, the code sometimes used a temporary stack variable to hold
details of a TCP segment. r338102 stopped using the variable to hold
segments, but did not actually remove the variable.
Because the variable is no longer used, we can safely remove it.
Approved by: re (gjb)
an inp marked FREED after the epoch(9) changes.
Check once we hold the lock and skip the inp if it is the case.
Contrary to IPv6 the locking of the inp is outside the multicast
section and hence a single check seems to suffice.
PR: 232192
Reviewed by: mmacy, markj
Approved by: re (kib)
Differential Revision: https://reviews.freebsd.org/D17540
but leaving the variable assignment outside the block, where it is no longer
used. Move both the variable and the assignment one block further in.
This should result in no functional changes. It will however make upcoming
changes slightly easier to apply.
Reviewed by: markj, jtl, tuexen
Approved by: re (kib)
Differential Revision: https://reviews.freebsd.org/D17525
epoch section without exiting that epoch section. This is bad for two
reasons: the epoch section won't exit, and we will leave the epoch tracker
from the stack on the epoch list.
Fix the epoch leak by making sure we exit epoch sections before returning.
Reviewed by: ae, gallatin, mmacy
Approved by: re (gjb, kib)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D17450
locally generated SCTP packets sent over IPv4. This make
the behaviour consistent with IPv6.
Reviewed by: ae@, bz@, jtl@
Approved by: re (kib@)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D17406
When getting the number of bytes to checksum make sure to convert the UDP
length to host byte order when the entire header is not in the first mbuf.
Reviewed by: jtl, tuexen, ae
Approved by: re (gjb), jtl (mentor)
Differential Revision: https://reviews.freebsd.org/D17357
With the new route cache feature udp_notify() will modify the inp when it
needs to invalidate the route cache. Ensure that we hold a write lock on
the inp before calling the function to ensure that multiple threads don't
race while trying to invalidate the cache (which previously lead to a page
fault).
Differential Revision: https://reviews.freebsd.org/D17246
Reviewed by: sbruno, bz, karels
Sponsored by: Dell EMC Isilon
Approved by: re (gjb)
This removes two assignments for the flags field being done
twice and adds one, which was missing.
Thanks to Felix Weinrank for reporting the issue he found
by using fuzz testing of the userland stack.
Approved by: re (kib@)
MFC after: 1 week
INP_INFO_UNLOCK_ASSERT() in TCP-related code. For encapsulated traffic
it is possible, that the code is running in net_epoch_preempt section,
and INP_INFO_UNLOCK_ASSERT() is very strict assertion for such case.
PR: 231428
Reviewed by: mmacy, tuexen
Approved by: re (kib)
Differential Revision: https://reviews.freebsd.org/D17335
sctp_process_cmsgs_for_init() and sctp_findassociation_cmsgs()
similar to sctp_find_cmsg() to improve consistency and avoid
the signed/unsigned issues in sctp_process_cmsgs_for_init()
and sctp_findassociation_cmsgs().
Thanks to andrew@ for reporting the problem he found using
syzcaller.
Approved by: re (kib@)
MFC after: 1 week
sending UDP encapsulated SCTP packets.
This is consistent with the behaviour that when such packets are received,
the corresponding UDP stats counter (udps_ipackets) is incremented.
Thanks to Peter Lei for making me aware of this inconsistency.
Approved by: re (kib@)
MFC after: 1 week
syncache_respond(). There is no functional change. The
parameter became unused in r313330, but wasn't removed.
Approved by: re (kib@)
MFC after: 1 month
Sponsored by: Netflix, Inc.
It is currently unused and reserved for future use to keep KBI/KPI.
Also add several spare pointers to be able extend structure if it
will be needed.
Approved by: re (gjb)
* Fix a bug where the SYN handling during established state was
applied to a front state.
* Move a check for retransmission after the timer handling.
This was suppressing timer based retransmissions.
* Fix an off-by one byte in the sequence number of retransmissions.
* Apply fixes corresponding to
https://svnweb.freebsd.org/changeset/base/336934
Reviewed by: rrs@
Approved by: re (kib@)
MFC after: 1 month
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16912
Lookups are protected by an epoch section, so the LB group linkage must
be a CK_LIST rather than a plain LIST. Furthermore, we were not
deferring LB group frees, so in_pcbremlbgrouphash() could race with
readers and cause a use-after-free.
Reviewed by: sbruno, Johannes Lundberg <johalun0@gmail.com>
Tested by: gallatin
Approved by: re (gjb)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17031
Reviewed by: bz, Johannes Lundberg <johalun0@gmail.com>
Approved by: re (kib)
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D17065
for the rt and lle cache were added in r191129 (2009).
To my best knowledge they have never been used and route caching
has converted the inp_rt field from that commit to inp_route
rendering this field and these flags obsolete.
Convert the pointer into a spare pointer to not change the size of
the structure anymore (and to have a spare pointer) and mark the
two fields as unused.
Reviewed by: markj, karels
Approved by: re (gjb)
Differential Revision: https://reviews.freebsd.org/D17062
adding the missing include files and changing a the type of cpuid which
would otherwise cause a false comparison with NETISR_CPUID_NONE.
Reviewed by: rrs
Approved by: re (marius)
Differential Revision: https://reviews.freebsd.org/D16891
Otherwise the "depends_on provider" guard in sctp.d does not work as
intended.
Reported by: mjg
Reviewed by: tuexen
Approved by: re (gjb)
Differential Revision: https://reviews.freebsd.org/D17057
No functional change intended.
Reviewed by: bz, Johannes Lundberg <johalun0@gmail.com>
Approved by: re (rgrimes)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17030
fast forwarding path, as it already works for IPv6 and for both of them
on old slow path.
PR: 231143
Reviewed by: ae
Approved by: re (gjb)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D17039
use sizeof() or explicit #definesi instead. No functional change.
This was suggested by jmg@.
MFC after: 1 month
XMFC with: r338053
Sponsored by: Netflix, Inc.
SCTP. They are based on what is specified in the Solaris DTrace manual
for Solaris 11.4.
Reviewed by: 0mp, dteske, markj
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D16839
socket resulted in sending fragmented IPV6 packets.
This is fixes by reducing the MSS to the appropriate value. In addtion,
if the socket option is set before the handshake happens, announce this
MSS to the peer. This is not stricly required, but done since TCP
is conservative.
PR: 173444
Reviewed by: bz@, rrs@
MFC after: 1 month
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16796
This was broken for IPv6 listening socket, which are not IPV6_ONLY,
and the accepted TCP connection was using IPv4.
Reviewed by: bz@, rrs@
MFC after: 1 month
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16792
This is not a functional change but a preperation for the upcoming
DTrace support. It is necessary to change the state in one
logical operation, even if it involves clearing the sub state
SHUTDOWN_PENDING.
MFC after: 1 month
reassembly inbound tcp segments. The old algorithm just blindly
dropped in segments without coalescing. This meant that every
segment could take up greater and greater room on the linked list
of segments. This of course is now subject to a tighter limit (100)
of segments which in a high BDP situation will cause us to be a
lot more in-efficent as we drop segments beyond 100 entries that
we receive. What this restructure does is cause the reassembly
buffer to coalesce segments putting an emphasis on the two
common cases (which avoid walking the list of segments) i.e.
where we add to the back of the queue of segments and where we
add to the front. We also have the reassembly buffer supporting
a couple of debug options (black box logging as well as counters
for code coverage). These are compiled out by default but can
be added by uncommenting the defines.
Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D16626
The TCP client side or the TCP server side when not using SYN-cookies
used the uptime as the TCP timestamp value. This patch uses in all
cases an offset, which is the result of a keyed hash function taking
the source and destination addresses and port numbers into account.
The keyed hash function is the same a used for the initial TSN.
Reviewed by: rrs@
MFC after: 1 month
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16636
toe_l2_resolve to fill up the complete vtag and not just the vid.
Reviewed by: kib@
MFC after: 1 week
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D16752
This is actually several different bugs:
- The code is not designed to handle inpcb deletion after interface deletion
- add reference for inpcb membership
- The multicast address has to be removed from interface lists when the refcount
goes to zero OR when the interface goes away
- decouple list disconnect from refcount (v6 only for now)
- ifmultiaddr can exist past being on interface lists
- add flag for tracking whether or not it's enqueued
- deferring freeing moptions makes the incpb cleanup code simpler but opens the
door wider still to races
- call inp_gcmoptions synchronously after dropping the the inpcb lock
Fundamentally multicast needs a rewrite - but keep applying band-aids for now.
Tested by: kp
Reported by: novel, kp, lwhsu
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
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, 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
It was lost when tryforward appeared. Now ip[6]_tryforward will be enabled
only when sending redirects for corresponding IP version is disabled via
sysctl. Otherwise will be used default forwarding function.
PR: 221137
Submitted by: mckay@
MFC after: 2 weeks
On PowerPC (and possibly other architectures), that doesn't use
EARLY_AP_STARTUP, the config task queue may be used initialized.
This was observed while trying to mount the root fs from NFS, as
reported here: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=230168.
This patch has 2 main changes:
1- Perform a basic initialization of qgroup_config, similar to
what is done in taskqgroup_adjust, but simpler.
This makes qgroup_config ready to be used during NFS root mount.
2- When EARLY_AP_STARTUP is not used, call inm_init() and
in6m_init() right before SI_SUB_ROOT_CONF, because bootp needs
to send multicast packages to request an IP.
PR: Bug 230168
Reported by: sbruno
Reviewed by: jhibbits, mmacy, sbruno
Approved by: jhibbits
Differential Revision: D16633
Currently, the per-queue limit is a function of the receive buffer
size and the MSS. In certain cases (such as connections with large
receive buffers), the per-queue segment limit can be quite large.
Because we process segments as a linked list, large queues may not
perform acceptably.
The better long-term solution is to make the queue more efficient.
But, in the short-term, we can provide a way for a system
administrator to set the maximum queue size.
We set the default queue limit to 100. This is an effort to balance
performance with a sane resource limit. Depending on their
environment, goals, etc., an administrator may choose to modify this
limit in either direction.
Reviewed by: jhb
Approved by: so
Security: FreeBSD-SA-18:08.tcp
Security: CVE-2018-6922
The dtrace provider for UDP-Lite is modeled after the UDP provider.
This fixes the bug that UDP-Lite packets were triggering the UDP
provider.
Thanks to dteske@ for providing the dwatch module.
Reviewed by: dteske@, markj@, rrs@
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D16377
r336940 introduced an "unused variable" warning on platforms which
support INET, but not INET6, like MALTA and MALTA64 as reported
by Mark Millard. Improve the #ifdefs to address this issue.
Sponsored by: Netflix, Inc.
TCP/IPv4 allows an implicit connection setup using sendto(), which
is used for TTCP and TCP fast open. This patch adds support for
TCP/IPv6.
While there, improve some tests for detecting multicast addresses,
which are mapped.
Reviewed by: bz@, kbowling@, rrs@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16458
When sending TCP segments from the timewait code path, a stored
value of the last sent window is used. Use the same code for
computing this in the timewait code path as in the main code
path used in tcp_output() to avoiv inconsistencies.
Reviewed by: rrs@
MFC after: 1 month
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16503
The following issues are fixed:
* Whenever a TCP server with TCP fast open enabled, calls accept(),
recv(), send(), and close() before the TCP-ACK segment has been received,
the TCP connection is just dropped and the reception of the TCP-ACK
segment triggers the sending of a TCP-RST segment.
* Whenever a TCP server with TCP fast open enabled, calls accept(), recv(),
send(), send(), and close() before the TCP-ACK segment has been received,
the first byte provided in the second send call is not transferred.
* Whenever a TCP client with TCP fast open enabled calls sendto() followed
by close() the TCP connection is just dropped.
Reviewed by: jtl@, kbowling@, rrs@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16485
These missing probe are mostly in the syncache and timewait code.
Reviewed by: markj@, rrs@
MFC after: 1 month
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16369
The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have grown at least 28 syscalls that use timespecs in some
way, leading many programs both inside and outside of the base system to
redefine those macros. It's better just to make the definitions public.
Our kernel currently defines two-argument versions of timespecadd and
timespecsub. NetBSD, OpenBSD, and FreeDesktop.org's libbsd, however, define
three-argument versions. Solaris also defines a three-argument version, but
only in its kernel. This revision changes our definition to match the
common three-argument version.
Bump _FreeBSD_version due to the breaking KPI change.
Discussed with: cem, jilles, ian, bde
Differential Revision: https://reviews.freebsd.org/D14725
sending an invalid segment into the reassembly
queue. This would happen if you enabled the
data after close option.
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D16453
When ABE was added (rS331214) to NewReno and leak fixed (rS333699) , it now has
a destructor (newreno_cb_destroy) for per connection state. Other congestion
controls may allocate and free cc_data on entry and exit, but the field is
never explicitly NULLed if moving back to NewReno which only internally
allocates stateful data (no entry contstructor) resulting in a situation where
newreno_cb_destory might be called on a junk pointer.
- NULL out cc_data in the framework after calling {cc}_cb_destroy
- free(9) checks for NULL so there is no need to perform not NULL checks
before calling free.
- Improve a comment about NewReno in tcp_ccalgounload
This is the result of a debugging session from Jason Wolfe, Jason Eggleston,
and mmacy@ and very helpful insight from lstewart@.
Submitted by: Kevin Bowling
Reviewed by: lstewart
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D16282
Fire UDP receive probes when a packet is received and there is no
endpoint consuming it. Fire the probe also if the TTL of the
received packet is smaller than the minimum required by the endpoint.
Clarify also in the man page, when the probe fires.
Reviewed by: dteske@, markj@, rrs@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16046
This deduplicates the code a bit, and also implicitly adds missing
callout_stop() to in[6]_lltable_delete_entry() functions.
PR: 209682, 225927
Submitted by: hselasky (previous version)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D4605
sysctl interface. This is similar to the TCP host cache.
Reviewed by: pkelsey@, kbowling@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D14554
When a client receives a SYN-ACK segment with a TFP fast open cookie,
but without an MSS option, an MSS value from uninitialised stack memory is used.
This patch ensures that in case no MSS option is included in the SYN-ACK,
the appropriate value as given in RFC 7413 is used.
Reviewed by: kbowling@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16175
"record-state" is similar to "keep-state", but it doesn't produce implicit
O_PROBE_STATE opcode in a rule. "set-limit" is like "limit", but it has the
same feature as "record-state", it is single opcode without implicit
O_PROBE_STATE opcode. "defer-action" is targeted to be used with dynamic
states. When rule with this opcode is matched, the rule's action will
not be executed, instead dynamic state will be created. And when this
state will be matched by "check-state", then rule action will be executed.
This allows create a more complicated rulesets.
Submitted by: lev
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D1776
cache.
Without this patch, TCP FO could be used when using alternate
TCP stack, but only existing entires in the TCP client cookie
cache could be used. This cache was not populated by connections
using alternate TCP stacks.
Sponsored by: Netflix, Inc.
whether the TCP FO support is enabled or not for the client side.
The code in tcp_fastopen_init() implicitly assumed that the sysctl
variable V_tcp_fastopen_client_enable was initialized to 0. This
was initially true, but was changed in r335610, which unmasked this
bug.
Thanks to Pieter de Goeje for reporting the issue on freebsd-net@
