Commit graph

498 commits

Author SHA1 Message Date
Oliver Hartkopp
f726f3d371 can: remove obsolete version strings
As pointed out by Jakub Kicinski here:
http://lore.kernel.org/r/20201009175751.5c54097f@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com
this patch removes the obsolete version information of the different
CAN protocols and the AF_CAN core module.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201012074354.25839-2-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2020-10-12 10:06:39 +02:00
David S. Miller
3ab0a7a0c3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Two minor conflicts:

1) net/ipv4/route.c, adding a new local variable while
   moving another local variable and removing it's
   initial assignment.

2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes.
   One pretty prints the port mode differently, whilst another
   changes the driver to try and obtain the port mode from
   the port node rather than the switch node.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-22 16:45:34 -07:00
Ido Schimmel
80690ec6b5 nexthop: Convert to blocking notification chain
Currently, the only listener of the nexthop notification chain is the
VXLAN driver. Subsequent patches will add more listeners (e.g., device
drivers such as netdevsim) that need to be able to block when processing
notifications.

Therefore, convert the notification chain to a blocking one. This is
safe as notifications are always emitted from process context.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-15 16:31:17 -07:00
Wei Wang
ac8f1710c1 tcp: reflect tos value received in SYN to the socket
This commit adds a new TCP feature to reflect the tos value received in
SYN, and send it out on the SYN-ACK, and eventually set the tos value of
the established socket with this reflected tos value. This provides a
way to set the traffic class/QoS level for all traffic in the same
connection to be the same as the incoming SYN request. It could be
useful in data centers to provide equivalent QoS according to the
incoming request.
This feature is guarded by /proc/sys/net/ipv4/tcp_reflect_tos, and is by
default turned off.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-10 13:15:40 -07:00
Pablo Neira Ayuso
67cc570eda netfilter: nf_tables: coalesce multiple notifications into one skbuff
On x86_64, each notification results in one skbuff allocation which
consumes at least 768 bytes due to the skbuff overhead.

This patch coalesces several notifications into one single skbuff, so
each notification consumes at least ~211 bytes, that ~3.5 times less
memory consumption. As a result, this is reducing the chances to exhaust
the netlink socket receive buffer.

Rule of thumb is that each notification batch only contains netlink
messages whose report flag is the same, nfnetlink_send() requires this
to do appropriate delivery to userspace, either via unicast (echo
mode) or multicast (monitor mode).

The skbuff control buffer is used to annotate the report flag for later
handling at the new coalescing routine.

The batch skbuff notification size is NLMSG_GOODSIZE, using a larger
skbuff would allow for more socket receiver buffer savings (to amortize
the cost of the skbuff even more), however, going over that size might
break userspace applications, so let's be conservative and stick to
NLMSG_GOODSIZE.

Reported-by: Phil Sutter <phil@nwl.cc>
Acked-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-09-08 13:02:44 +02:00
Jakub Sitnicki
ab53cad90e bpf, netns: Keep a list of attached bpf_link's
To support multi-prog link-based attachments for new netns attach types, we
need to keep track of more than one bpf_link per attach type. Hence,
convert net->bpf.links into a list, that currently can be either empty or
have just one item.

Instead of reusing bpf_prog_list from bpf-cgroup, we link together
bpf_netns_link's themselves. This makes list management simpler as we don't
have to allocate, initialize, and later release list elements. We can do
this because multi-prog attachment will be available only for bpf_link, and
we don't need to build a list of programs attached directly and indirectly
via links.

No functional changes intended.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200625141357.910330-4-jakub@cloudflare.com
2020-06-30 10:45:08 -07:00
Jakub Sitnicki
695c12147a bpf, netns: Keep attached programs in bpf_prog_array
Prepare for having multi-prog attachments for new netns attach types by
storing programs to run in a bpf_prog_array, which is well suited for
iterating over programs and running them in sequence.

After this change bpf(PROG_QUERY) may block to allocate memory in
bpf_prog_array_copy_to_user() for collected program IDs. This forces a
change in how we protect access to the attached program in the query
callback. Because bpf_prog_array_copy_to_user() can sleep, we switch from
an RCU read lock to holding a mutex that serializes updaters.

Because we allow only one BPF flow_dissector program to be attached to
netns at all times, the bpf_prog_array pointed by net->bpf.run_array is
always either detached (null) or one element long.

No functional changes intended.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200625141357.910330-3-jakub@cloudflare.com
2020-06-30 10:45:08 -07:00
Jakub Sitnicki
7f045a49fe bpf: Add link-based BPF program attachment to network namespace
Extend bpf() syscall subcommands that operate on bpf_link, that is
LINK_CREATE, LINK_UPDATE, OBJ_GET_INFO, to accept attach types tied to
network namespaces (only flow dissector at the moment).

Link-based and prog-based attachment can be used interchangeably, but only
one can exist at a time. Attempts to attach a link when a prog is already
attached directly, and the other way around, will be met with -EEXIST.
Attempts to detach a program when link exists result in -EINVAL.

Attachment of multiple links of same attach type to one netns is not
supported with the intention to lift the restriction when a use-case
presents itself. Because of that link create returns -E2BIG when trying to
create another netns link, when one already exists.

Link-based attachments to netns don't keep a netns alive by holding a ref
to it. Instead links get auto-detached from netns when the latter is being
destroyed, using a pernet pre_exit callback.

When auto-detached, link lives in defunct state as long there are open FDs
for it. -ENOLINK is returned if a user tries to update a defunct link.

Because bpf_link to netns doesn't hold a ref to struct net, special care is
taken when releasing, updating, or filling link info. The netns might be
getting torn down when any of these link operations are in progress. That
is why auto-detach and update/release/fill_info are synchronized by the
same mutex. Also, link ops have to always check if auto-detach has not
happened yet and if netns is still alive (refcnt > 0).

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200531082846.2117903-5-jakub@cloudflare.com
2020-06-01 15:21:03 -07:00
Jakub Sitnicki
a3fd7ceee0 net: Introduce netns_bpf for BPF programs attached to netns
In order to:

 (1) attach more than one BPF program type to netns, or
 (2) support attaching BPF programs to netns with bpf_link, or
 (3) support multi-prog attach points for netns

we will need to keep more state per netns than a single pointer like we
have now for BPF flow dissector program.

Prepare for the above by extracting netns_bpf that is part of struct net,
for storing all state related to BPF programs attached to netns.

Turn flow dissector callbacks for querying/attaching/detaching a program
into generic ones that operate on netns_bpf. Next patch will move the
generic callbacks into their own module.

This is similar to how it is organized for cgroup with cgroup_bpf.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20200531082846.2117903-3-jakub@cloudflare.com
2020-06-01 15:21:02 -07:00
Roopa Prabhu
8590ceedb7 nexthop: add support for notifiers
This patch adds nexthop add/del notifiers. To be used by
vxlan driver in a later patch. Could possibly be used by
switchdev drivers in the future.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-22 14:00:38 -07:00
Eric Dumazet
a70437cc09 tcp: add hrtimer slack to sack compression
Add a sysctl to control hrtimer slack, default of 100 usec.

This gives the opportunity to reduce system overhead,
and help very short RTT flows.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30 13:24:01 -07:00
Roopa Prabhu
4f80116d3d net: ipv4: add sysctl for nexthop api compatibility mode
Current route nexthop API maintains user space compatibility
with old route API by default. Dumps and netlink notifications
support both new and old API format. In systems which have
moved to the new API, this compatibility mode cancels some
of the performance benefits provided by the new nexthop API.

This patch adds new sysctl nexthop_compat_mode which is on
by default but provides the ability to turn off compatibility
mode allowing systems to run entirely with the new routing
API. Old route API behaviour and support is not modified by this
sysctl.

Uses a single sysctl to cover both ipv4 and ipv6 following
other sysctls. Covers dumps and delete notifications as
suggested by David Ahern.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-28 12:50:37 -07:00
Florian Westphal
fc518953bc mptcp: add and use MIB counter infrastructure
Exported via same /proc file as the Linux TCP MIB counters, so "netstat -s"
or "nstat" will show them automatically.

The MPTCP MIB counters are allocated in a distinct pcpu area in order to
avoid bloating/wasting TCP pcpu memory.

Counters are allocated once the first MPTCP socket is created in a
network namespace and free'd on exit.

If no sockets have been allocated, all-zero mptcp counters are shown.

The MIB counter list is taken from the multipath-tcp.org kernel, but
only a few counters have been picked up so far.  The counter list can
be increased at any time later on.

v2 -> v3:
 - remove 'inline' in foo.c files (David S. Miller)

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29 22:14:49 -07:00
Kuniyuki Iwashima
4b01a96742 tcp: bind(0) remove the SO_REUSEADDR restriction when ephemeral ports are exhausted.
Commit aacd9289af ("tcp: bind() use stronger
condition for bind_conflict") introduced a restriction to forbid to bind
SO_REUSEADDR enabled sockets to the same (addr, port) tuple in order to
assign ports dispersedly so that we can connect to the same remote host.

The change results in accelerating port depletion so that we fail to bind
sockets to the same local port even if we want to connect to the different
remote hosts.

You can reproduce this issue by following instructions below.

  1. # sysctl -w net.ipv4.ip_local_port_range="32768 32768"
  2. set SO_REUSEADDR to two sockets.
  3. bind two sockets to (localhost, 0) and the latter fails.

Therefore, when ephemeral ports are exhausted, bind(0) should fallback to
the legacy behaviour to enable the SO_REUSEADDR option and make it possible
to connect to different remote (addr, port) tuples.

This patch allows us to bind SO_REUSEADDR enabled sockets to the same
(addr, port) only when net.ipv4.ip_autobind_reuse is set 1 and all
ephemeral ports are exhausted. This also allows connect() and listen() to
share ports in the following way and may break some applications. So the
ip_autobind_reuse is 0 by default and disables the feature.

  1. setsockopt(sk1, SO_REUSEADDR)
  2. setsockopt(sk2, SO_REUSEADDR)
  3. bind(sk1, saddr, 0)
  4. bind(sk2, saddr, 0)
  5. connect(sk1, daddr)
  6. listen(sk2)

If it is set 1, we can fully utilize the 4-tuples, but we should use
IP_BIND_ADDRESS_NO_PORT for bind()+connect() as possible.

The notable thing is that if all sockets bound to the same port have
both SO_REUSEADDR and SO_REUSEPORT enabled, we can bind sockets to an
ephemeral port and also do listen().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-12 12:08:09 -07:00
David S. Miller
4d8773b68e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor conflict in mlx5 because changes happened to code that has
moved meanwhile.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-26 10:40:21 +01:00
Pablo Neira Ayuso
eb014de4fd netfilter: nf_tables: autoload modules from the abort path
This patch introduces a list of pending module requests. This new module
list is composed of nft_module_request objects that contain the module
name and one status field that tells if the module has been already
loaded (the 'done' field).

In the first pass, from the preparation phase, the netlink command finds
that a module is missing on this list. Then, a module request is
allocated and added to this list and nft_request_module() returns
-EAGAIN. This triggers the abort path with the autoload parameter set on
from nfnetlink, request_module() is called and the module request enters
the 'done' state. Since the mutex is released when loading modules from
the abort phase, the module list is zapped so this is iteration occurs
over a local list. Therefore, the request_module() calls happen when
object lists are in consistent state (after fulling aborting the
transaction) and the commit list is empty.

On the second pass, the netlink command will find that it already tried
to load the module, so it does not request it again and
nft_request_module() returns 0. Then, there is a look up to find the
object that the command was missing. If the module was successfully
loaded, the command proceeds normally since it finds the missing object
in place, otherwise -ENOENT is reported to userspace.

This patch also updates nfnetlink to include the reason to enter the
abort phase, which is required for this new autoload module rationale.

Fixes: ec7470b834 ("netfilter: nf_tables: store transaction list locally while requesting module")
Reported-by: syzbot+29125d208b3dae9a7019@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-01-24 20:54:29 +01:00
Kevin(Yudong) Yang
65e6d90168 net-tcp: Disable TCP ssthresh metrics cache by default
This patch introduces a sysctl knob "net.ipv4.tcp_no_ssthresh_metrics_save"
that disables TCP ssthresh metrics cache by default. Other parts of TCP
metrics cache, e.g. rtt, cwnd, remain unchanged.

As modern networks becoming more and more dynamic, TCP metrics cache
today often causes more harm than benefits. For example, the same IP
address is often shared by different subscribers behind NAT in residential
networks. Even if the IP address is not shared by different users,
caching the slow-start threshold of a previous short flow using loss-based
congestion control (e.g. cubic) often causes the future longer flows of
the same network path to exit slow-start prematurely with abysmal
throughput.

Caching ssthresh is very risky and can lead to terrible performance.
Therefore it makes sense to make disabling ssthresh caching by
default and opt-in for specific networks by the administrators.
This practice also has worked well for several years of deployment with
CUBIC congestion control at Google.

Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Kevin(Yudong) Yang <yyd@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-09 20:17:48 -08:00
Paolo Abeni
b9b33e7c24 ipv6: keep track of routes using src
Use a per namespace counter, increment it on successful creation
of any route using the source address, decrement it on deletion
of such routes.

This allows us to check easily if the routing decision in the
current namespace depends on the packet source. Will be used
by the next patch.

Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21 14:45:55 -08:00
Xin Long
34515e94c9 sctp: add support for Primary Path Switchover
This is a new feature defined in section 5 of rfc7829: "Primary Path
Switchover". By introducing a new tunable parameter:

  Primary.Switchover.Max.Retrans (PSMR)

The primary path will be changed to another active path when the path
error counter on the old primary path exceeds PSMR, so that "the SCTP
sender is allowed to continue data transmission on a new working path
even when the old primary destination address becomes active again".

This patch is to add this tunable parameter, 'ps_retrans' per netns,
sock, asoc and transport. It also allows a user to change ps_retrans
per netns by sysctl, and ps_retrans per sock/asoc/transport will be
initialized with it.

The check will be done in sctp_do_8_2_transport_strike() when this
feature is enabled.

Note this feature is disabled by initializing 'ps_retrans' per netns
as 0xffff by default, and its value can't be less than 'pf_retrans'
when changing by sysctl.

v3->v4:
  - add define SCTP_PS_RETRANS_MAX 0xffff, and use it on extra2 of
    sysctl 'ps_retrans'.
  - add a new entry for ps_retrans on ip-sysctl.txt.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-08 14:18:32 -08:00
Xin Long
aef587be42 sctp: add pf_expose per netns and sock and asoc
As said in rfc7829, section 3, point 12:

  The SCTP stack SHOULD expose the PF state of its destination
  addresses to the ULP as well as provide the means to notify the
  ULP of state transitions of its destination addresses from
  active to PF, and vice versa.  However, it is recommended that
  an SCTP stack implementing SCTP-PF also allows for the ULP to be
  kept ignorant of the PF state of its destinations and the
  associated state transitions, thus allowing for retention of the
  simpler state transition model of [RFC4960] in the ULP.

Not only does it allow to expose the PF state to ULP, but also
allow to ignore sctp-pf to ULP.

So this patch is to add pf_expose per netns, sock and asoc. And in
sctp_assoc_control_transport(), ulp_notify will be set to false if
asoc->expose is not 'enabled' in next patch.

It also allows a user to change pf_expose per netns by sysctl, and
pf_expose per sock and asoc will be initialized with it.

Note that pf_expose also works for SCTP_GET_PEER_ADDR_INFO sockopt,
to not allow a user to query the state of a sctp-pf peer address
when pf_expose is 'disabled', as said in section 7.3.

v1->v2:
  - Fix a build warning noticed by Nathan Chancellor.
v2->v3:
  - set pf_expose to UNUSED by default to keep compatible with old
    applications.
v3->v4:
  - add a new entry for pf_expose on ip-sysctl.txt, as Marcelo suggested.
  - change this patch to 1/5, and move sctp_assoc_control_transport
    change into 2/5, as Marcelo suggested.
  - use SCTP_PF_EXPOSE_UNSET instead of SCTP_PF_EXPOSE_UNUSED, and
    set SCTP_PF_EXPOSE_UNSET to 0 in enum, as Marcelo suggested.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-08 14:18:32 -08:00
Jakub Kicinski
d26b698dd3 net/tls: add skeleton of MIB statistics
Add a skeleton structure for adding TLS statistics.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-05 16:29:00 -07:00
Marc Kleine-Budde
564577dfee can: netns: remove "can_" prefix from members struct netns_can
This patch improves the code reability by removing the redundant "can_"
prefix from the members of struct netns_can (as the struct netns_can itself
is the member "can" of the struct net.)

The conversion is done with:

	sed -i \
		-e "s/struct can_dev_rcv_lists \*can_rx_alldev_list;/struct can_dev_rcv_lists *rx_alldev_list;/" \
		-e "s/spinlock_t can_rcvlists_lock;/spinlock_t rcvlists_lock;/" \
		-e "s/struct timer_list can_stattimer;/struct timer_list stattimer; /" \
		-e "s/can\.can_rx_alldev_list/can.rx_alldev_list/g" \
		-e "s/can\.can_rcvlists_lock/can.rcvlists_lock/g" \
		-e "s/can\.can_stattimer/can.stattimer/g" \
		include/net/netns/can.h \
		net/can/*.[ch]

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2019-09-04 13:29:14 +02:00
Marc Kleine-Budde
2341086df4 can: netns: give members of struct netns_can holding the statistics a sensible name
This patch gives the members of the struct netns_can that are holding
the statistics a sensible name, by renaming struct netns_can::can_stats
into struct netns_can::pkg_stats and struct netns_can::can_pstats into
struct netns_can::rcv_lists_stats.

The conversion is done with:

	sed -i \
		-e "s:\(struct[^*]*\*\)can_stats;.*:\1pkg_stats;:" \
		-e "s:\(struct[^*]*\*\)can_pstats;.*:\1rcv_lists_stats;:" \
		-e "s/can\.can_stats/can.pkg_stats/g" \
		-e "s/can\.can_pstats/can.rcv_lists_stats/g" \
		net/can/*.[ch] \
		include/net/netns/can.h

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2019-09-04 13:29:13 +02:00
Marc Kleine-Budde
6c43bb3a41 can: netns: give structs holding the CAN statistics a sensible name
This patch renames both "struct s_stats" and "struct s_pstats", to
"struct can_pkg_stats" and "struct can_rcv_lists_stats" to better
reflect their meaning and improve code readability.

The conversion is done with:

	sed -i \
		-e "s/struct s_stats/struct can_pkg_stats/g" \
		-e "s/struct s_pstats/struct can_rcv_lists_stats/g" \
		net/can/*.[ch] \
		include/net/netns/can.h

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2019-09-04 13:29:13 +02:00
Xin Long
1b0b8114b9 sctp: make ecn flag per netns and endpoint
This patch is to add ecn flag for both netns_sctp and sctp_endpoint,
net->sctp.ecn_enable is set 1 by default, and ep->ecn_enable will
be initialized with net->sctp.ecn_enable.

asoc->peer.ecn_capable will be set during negotiation only when
ep->ecn_enable is set on both sides.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-27 20:54:14 -07:00
Josh Hunt
c04b79b6cf tcp: add new tcp_mtu_probe_floor sysctl
The current implementation of TCP MTU probing can considerably
underestimate the MTU on lossy connections allowing the MSS to get down to
48. We have found that in almost all of these cases on our networks these
paths can handle much larger MTUs meaning the connections are being
artificially limited. Even though TCP MTU probing can raise the MSS back up
we have seen this not to be the case causing connections to be "stuck" with
an MSS of 48 when heavy loss is present.

Prior to pushing out this change we could not keep TCP MTU probing enabled
b/c of the above reasons. Now with a reasonble floor set we've had it
enabled for the past 6 months.

The new sysctl will still default to TCP_MIN_SND_MSS (48), but gives
administrators the ability to control the floor of MSS probing.

Signed-off-by: Josh Hunt <johunt@akamai.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-09 13:03:30 -07:00
David S. Miller
13091aa305 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Honestly all the conflicts were simple overlapping changes,
nothing really interesting to report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-17 20:20:36 -07:00
Eric Dumazet
5f3e2bf008 tcp: add tcp_min_snd_mss sysctl
Some TCP peers announce a very small MSS option in their SYN and/or
SYN/ACK messages.

This forces the stack to send packets with a very high network/cpu
overhead.

Linux has enforced a minimal value of 48. Since this value includes
the size of TCP options, and that the options can consume up to 40
bytes, this means that each segment can include only 8 bytes of payload.

In some cases, it can be useful to increase the minimal value
to a saner value.

We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility
reasons.

Note that TCP_MAXSEG socket option enforces a minimal value
of (TCP_MIN_MSS). David Miller increased this minimal value
in commit c39508d6f1 ("tcp: Make TCP_MAXSEG minimum more correct.")
from 64 to 88.

We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS.

CVE-2019-11479 -- tcp mss hardcoded to 48

Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Jonathan Looney <jtl@netflix.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Bruce Curtis <brucec@netflix.com>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-15 18:47:31 -07:00
David Ahern
ab84be7e54 net: Initial nexthop code
Barebones start point for nexthops. Implementation for RTM commands,
notifications, management of rbtree for holding nexthops by id, and
kernel side data structures for nexthops and nexthop config.

Nexthops are maintained in an rbtree sorted by id. Similar to routes,
nexthops are configured per namespace using netns_nexthop struct added
to struct net.

Nexthop notifications are sent when a nexthop is added or deleted,
but NOT if the delete is due to a device event or network namespace
teardown (which also involves device events). Applications are
expected to use the device down event to flush nexthops and any
routes used by the nexthops.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-28 21:37:30 -07:00
Eric Dumazet
4907abc605 net: dynamically allocate fqdir structures
Following patch will add rcu grace period before fqdir
rhashtable destruction, so we need to dynamically allocate
fqdir structures to not force expensive synchronize_rcu() calls
in netns dismantle path.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-26 14:08:05 -07:00
Eric Dumazet
803fdd9968 net: rename struct fqdir fields
Rename the @frags fields from structs netns_ipv4, netns_ipv6,
netns_nf_frag and netns_ieee802154_lowpan to @fqdir

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-26 14:08:05 -07:00
Eric Dumazet
6ce3b4dcee inet: rename netns_frags to fqdir
1) struct netns_frags is renamed to struct fqdir
  This structure is really holding many frag queues in a hash table.

2) (struct inet_frag_queue)->net field is renamed to fqdir
  since net is generally associated to a 'struct net' pointer
  in networking stack.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-26 14:08:04 -07:00
Tonghao Zhang
8f14c99c7e netfilter: conntrack: limit sysctl setting for boolean options
We use the zero and one to limit the boolean options setting.
After this patch we only set 0 or 1 to boolean options for nf
conntrack sysctl.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-30 14:18:56 +02:00
Stephen Suryaputra
0bc1998544 ipv6: Add rate limit mask for ICMPv6 messages
To make ICMPv6 closer to ICMPv4, add ratemask parameter. Since the ICMP
message types use larger numeric values, a simple bitmask doesn't fit.
I use large bitmap. The input and output are the in form of list of
ranges. Set the default to rate limit all error messages but Packet Too
Big. For Packet Too Big, use ratemask instead of hard-coded.

There are functions where icmpv6_xrlim_allow() and icmpv6_global_allow()
aren't called. This patch only adds them to icmpv6_echo_reply().

Rate limiting error messages is mandated by RFC 4443 but RFC 4890 says
that it is also acceptable to rate limit informational messages. Thus,
I removed the current hard-coded behavior of icmpv6_mask_allow() that
doesn't rate limit informational messages.

v2: Add dummy function proc_do_large_bitmap() if CONFIG_PROC_SYSCTL
    isn't defined, expand the description in ip-sysctl.txt and remove
    unnecessary conditional before kfree().
v3: Inline the bitmap instead of dynamically allocated. Still is a
    pointer to it is needed because of the way proc_do_large_bitmap work.

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-18 16:58:37 -07:00
David S. Miller
f83f715195 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor comment merge conflict in mlx5.

Staging driver has a fixup due to the skb->xmit_more changes
in 'net-next', but was removed in 'net'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-05 14:14:19 -07:00
Eric Dumazet
355b985537 netns: provide pure entropy for net_hash_mix()
net_hash_mix() currently uses kernel address of a struct net,
and is used in many places that could be used to reveal this
address to a patient attacker, thus defeating KASLR, for
the typical case (initial net namespace, &init_net is
not dynamically allocated)

I believe the original implementation tried to avoid spending
too many cycles in this function, but security comes first.

Also provide entropy regardless of CONFIG_NET_NS.

Fixes: 0b4419162a ("netns: introduce the net_hash_mix "salt" for hashes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-28 17:00:45 -07:00
Eric Dumazet
df453700e8 inet: switch IP ID generator to siphash
According to Amit Klein and Benny Pinkas, IP ID generation is too weak
and might be used by attackers.

Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix())
having 64bit key and Jenkins hash is risky.

It is time to switch to siphash and its 128bit keys.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-27 14:29:26 -07:00
Stephen Suryaputra
0b03a5ca8b ipv6: Add icmp_echo_ignore_anycast for ICMPv6
In addition to icmp_echo_ignore_multicast, there is a need to also
prevent responding to pings to anycast addresses for security.

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 16:29:37 -07:00
Stephen Suryaputra
03f1eccc7a ipv6: Add icmp_echo_ignore_multicast support for ICMPv6
IPv4 has icmp_echo_ignore_broadcast to prevent responding to broadcast pings.
IPv6 needs a similar mechanism.

v1->v2:
- Remove NET_IPV6_ICMP_ECHO_IGNORE_MULTICAST.

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-19 14:29:51 -07:00
Kefeng Wang
75efc250d2 ipv6: icmp: use percpu allocation
Use percpu allocation for the ipv6.icmp_sk.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-24 21:57:26 -08:00
David S. Miller
ec7146db15 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2019-01-29

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Teach verifier dead code removal, this also allows for optimizing /
   removing conditional branches around dead code and to shrink the
   resulting image. Code store constrained architectures like nfp would
   have hard time doing this at JIT level, from Jakub.

2) Add JMP32 instructions to BPF ISA in order to allow for optimizing
   code generation for 32-bit sub-registers. Evaluation shows that this
   can result in code reduction of ~5-20% compared to 64 bit-only code
   generation. Also add implementation for most JITs, from Jiong.

3) Add support for __int128 types in BTF which is also needed for
   vmlinux's BTF conversion to work, from Yonghong.

4) Add a new command to bpftool in order to dump a list of BPF-related
   parameters from the system or for a specific network device e.g. in
   terms of available prog/map types or helper functions, from Quentin.

5) Add AF_XDP sock_diag interface for querying sockets from user
   space which provides information about the RX/TX/fill/completion
   rings, umem, memory usage etc, from Björn.

6) Add skb context access for skb_shared_info->gso_segs field, from Eric.

7) Add support for testing flow dissector BPF programs by extending
   existing BPF_PROG_TEST_RUN infrastructure, from Stanislav.

8) Split BPF kselftest's test_verifier into various subgroups of tests
   in order better deal with merge conflicts in this area, from Jakub.

9) Add support for queue/stack manipulations in bpftool, from Stanislav.

10) Document BTF, from Yonghong.

11) Dump supported ELF section names in libbpf on program load
    failure, from Taeung.

12) Silence a false positive compiler warning in verifier's BTF
    handling, from Peter.

13) Fix help string in bpftool's feature probing, from Prashant.

14) Remove duplicate includes in BPF kselftests, from Yue.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-28 19:38:33 -08:00
Björn Töpel
1d0dc06930 net: xsk: track AF_XDP sockets on a per-netns list
Track each AF_XDP socket in a per-netns list. This will be used later
by the sock_diag interface for querying sockets from userspace.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-25 01:50:03 +01:00
Florian Westphal
2a389de86e netfilter: conntrack: remove l4proto init and get_net callbacks
Those were needed we still had modular trackers.
As we don't have those anymore, prefer direct calls and remove all
the (un)register infrastructure associated with this.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
70aed4647c netfilter: conntrack: remove sysctl registration helpers
After previous patch these are not used anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:34 +01:00
Florian Westphal
22fc4c4c9f netfilter: conntrack: gre: switch module to be built-in
This makes the last of the modular l4 trackers 'bool'.

After this, all infrastructure to handle dynamic l4 protocol registration
becomes obsolete and can be removed in followup patches.

Old:
302824 net/netfilter/nf_conntrack.ko
 21504 net/netfilter/nf_conntrack_proto_gre.ko

New:
313728 net/netfilter/nf_conntrack.ko

Old:
   text	   data	    bss	    dec	    hex	filename
   6281	   1732	      4	   8017	   1f51	nf_conntrack_proto_gre.ko
 108356	  20613	    236	 129205	  1f8b5	nf_conntrack.ko
New:
 112095	  21381	    240	 133716	  20a54	nf_conntrack.ko

The size increase is only temporary.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
David S. Miller
c3e5336925 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

1) Support for destination MAC in ipset, from Stefano Brivio.

2) Disallow all-zeroes MAC address in ipset, also from Stefano.

3) Add IPSET_CMD_GET_BYNAME and IPSET_CMD_GET_BYINDEX commands,
   introduce protocol version number 7, from Jozsef Kadlecsik.
   A follow up patch to fix ip_set_byindex() is also included
   in this batch.

4) Honor CTA_MARK_MASK from ctnetlink, from Andreas Jaggi.

5) Statify nf_flow_table_iterate(), from Taehee Yoo.

6) Use nf_flow_table_iterate() to simplify garbage collection in
   nf_flow_table logic, also from Taehee Yoo.

7) Don't use _bh variants of call_rcu(), rcu_barrier() and
   synchronize_rcu_bh() in Netfilter, from Paul E. McKenney.

8) Remove NFC_* cache definition from the old caching
   infrastructure.

9) Remove layer 4 port rover in NAT helpers, use random port
   instead, from Florian Westphal.

10) Use strscpy() in ipset, from Qian Cai.

11) Remove NF_NAT_RANGE_PROTO_RANDOM_FULLY branch now that
    random port is allocated by default, from Xiaozhou Liu.

12) Ignore NF_NAT_RANGE_PROTO_RANDOM too, from Florian Westphal.

13) Limit port allocation selection routine in NAT to avoid
    softlockup splats when most ports are in use, from Florian.

14) Remove unused parameters in nf_ct_l4proto_unregister_sysctl()
    from Yafang Shao.

15) Direct call to nf_nat_l4proto_unique_tuple() instead of
    indirection, from Florian Westphal.

16) Several patches to remove all layer 4 NAT indirections,
    remove nf_nat_l4proto struct, from Florian Westphal.

17) Fix RTP/RTCP source port translation when SNAT is in place,
    from Alin Nastac.

18) Selective rule dump per chain, from Phil Sutter.

19) Revisit CLUSTERIP target, this includes a deadlock fix from
    netns path, sleep in atomic, remove bogus WARN_ON_ONCE()
    and disallow mismatching IP address and MAC address.
    Patchset from Taehee Yoo.

20) Update UDP timeout to stream after 2 seconds, from Florian.

21) Shrink UDP established timeout to 120 seconds like TCP timewait.

22) Sysctl knobs to set GRE timeouts, from Yafang Shao.

23) Move seq_print_acct() to conntrack core file, from Florian.

24) Add enum for conntrack sysctl knobs, also from Florian.

25) Place nf_conntrack_acct, nf_conntrack_helper, nf_conntrack_events
    and nf_conntrack_timestamp knobs in the core, from Florian Westphal.
    As a side effect, shrink netns_ct structure by removing obsolete
    sysctl anchors, also from Florian.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-20 18:20:26 -08:00
Florian Westphal
8527f9df04 netfilter: netns: shrink netns_ct struct
remove the obsolete sysctl anchors and move auto_assign_helper_warned
to avoid/cover a hole.  Reduces size by 40 bytes on 64 bit.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-21 00:51:56 +01:00
Florian Westphal
24969facd7 xfrm: policy: store inexact policies in an rhashtable
Switch packet-path lookups for inexact policies to rhashtable.

In this initial version, we now no longer need to search policies with
non-matching address family and type.

Next patch will add the if_id as well so lookups from the xfrm interface
driver only need to search inexact policies for that device.

Future patches will augment the hlist in each rhash bucket with a tree
and pre-sort policies according to daddr/prefix.

A single rhashtable is used.  In order to avoid a full rhashtable walk on
netns exit, the bins get placed on a pernet list, i.e. we add almost no
cost for network namespaces that had no xfrm policies.

The inexact lists are kept in place, and policies are added to both the
per-rhash-inexact list and a pernet one.

The latter is needed for the control plane to handle migrate -- these
requests do not consider the if_id, so if we'd remove the inexact_list
now we would have to search all hash buckets and then figure
out which matching policy candidate is the most recent one -- this appears
a bit harder than just keeping the 'old' inexact list for this purpose.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-11-09 11:57:47 +01:00
Mike Manning
6897445fb1 net: provide a sysctl raw_l3mdev_accept for raw socket lookup with VRFs
Add a sysctl raw_l3mdev_accept to control raw socket lookup in a manner
similar to use of tcp_l3mdev_accept for stream and of udp_l3mdev_accept
for datagram sockets. Have this default to enabled for reasons of
backwards compatibility. This is so as to specify the output device
with cmsg and IP_PKTINFO, but using a socket not bound to the
corresponding VRF. This allows e.g. older ping implementations to be
run with specifying the device but without executing it in the VRF.
If the option is disabled, packets received in a VRF context are only
handled by a raw socket bound to the VRF, and correspondingly packets
in the default VRF are only handled by a socket not bound to any VRF.

Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:12:38 -08:00
David Ahern
7c6bb7d2fa net/ipv6: Add knob to skip DELROUTE message on device down
Another difference between IPv4 and IPv6 is the generation of RTM_DELROUTE
notifications when a device is taken down (admin down) or deleted. IPv4
does not generate a message for routes evicted by the down or delete;
IPv6 does. A NOS at scale really needs to avoid these messages and have
IPv4 and IPv6 behave similarly, relying on userspace to handle link
notifications and evict the routes.

At this point existing user behavior needs to be preserved. Since
notifications are a global action (not per app) the only way to preserve
existing behavior and allow the messages to be skipped is to add a new
sysctl (net/ipv6/route/skip_notify_on_dev_down) which can be set to
disable the notificatioons.

IPv6 route code already supports the option to skip the message (it is
used for multipath routes for example). Besides the new sysctl we need
to pass the skip_notify setting through the generic fib6_clean and
fib6_walk functions to fib6_clean_node and to set skip_notify on calls
to __ip_del_rt for the addrconf_ifdown path.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 09:47:02 -07:00