linux-stable.git/drivers/net/vrf.c, branch linux-6.3.y

net: vrf: determine the dst using the original ifindex for multicast

2022-12-22T01:47:37+00:00

Multicast packets received on an interface bound to a VRF are marked as
belonging to the VRF and the skb device is updated to point to the VRF
device itself. This was fine even when a route was associated to a
device as when performing a fib table lookup 'oif' in fib6_table_lookup
(coming from 'skb->dev->ifindex' in ip6_route_input) was set to 0 when
FLOWI_FLAG_SKIP_NH_OIF was set.

With commit 40867d74c374 ("net: Add l3mdev index to flow struct and
avoid oif reset for port devices") this is not longer true and multicast
traffic is not received on the original interface.

Instead of adding back a similar check in fib6_table_lookup determine
the dst using the original ifindex for multicast VRF traffic. To make
things consistent across the function do the above for all strict
packets, which was the logic before commit 6f12fa775530 ("vrf: mark skb
for multicast or link-local as enslaved to VRF"). Note that reverting to
this behavior should be fine as the change was about marking packets
belonging to the VRF, not about their dst.

Fixes: 40867d74c374 ("net: Add l3mdev index to flow struct and avoid oif reset for port devices")
Reported-by: Jianlin Shi 
Signed-off-by: Antoine Tenart 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20221220171825.1172237-1-atenart@kernel.org
Signed-off-by: Jakub Kicinski

net: Remove the obsolte u64_stats_fetch_*_irq() users (drivers).

2022-10-29T03:13:54+00:00

Now that the 32bit UP oddity is gone and 32bit uses always a sequence
count, there is no need for the fetch_irq() variants anymore.

Convert to the regular interface.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Sebastian Andrzej Siewior 
Acked-by: Peter Zijlstra (Intel) 
Signed-off-by: Jakub Kicinski

net: move from strlcpy with unused retval to strscpy

2022-08-31T21:11:07+00:00

Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang 
Acked-by: Marc Kleine-Budde  # for CAN
Link: https://lore.kernel.org/r/20220830201457.7984-1-wsa+renesas@sang-engineering.com
Signed-off-by: Jakub Kicinski

xfrm: no need to set DST_NOPOLICY in IPv4

2022-06-10T09:01:36+00:00

This is a cleanup patch following commit e6175a2ed1f1
("xfrm: fix "disable_policy" flag use when arriving from different devices")
which made DST_NOPOLICY no longer be used for inbound policy checks.

On outbound the flag was set, but never used.

As such, avoid setting it altogether and remove the nopolicy argument
from rt_dst_alloc().

Signed-off-by: Eyal Birger 
Reviewed-by: Nicolas Dichtel 
Signed-off-by: Steffen Klassert

net: rename reference+tracking helpers

2022-06-10T04:52:55+00:00

Netdev reference helpers have a dev_ prefix for historic
reasons. Renaming the old helpers would be too much churn
but we can rename the tracking ones which are relatively
recent and should be the default for new code.

Rename:
 dev_hold_track()    -> netdev_hold()
 dev_put_track()     -> netdev_put()
 dev_replace_track() -> netdev_ref_replace()

Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski

vrf: fix packet sniffing for traffic originating from ip tunnels

2022-04-01T10:56:55+00:00

in commit 048939088220
("vrf: add mac header for tunneled packets when sniffer is attached")
an Ethernet header was cooked for traffic originating from tunnel devices.

However, the header is added based on whether the mac_header is unset
and ignores cases where the device doesn't expose a mac header to upper
layers, such as in ip tunnels like ipip and gre.

Traffic originating from such devices still appears garbled when capturing
on the vrf device.

Fix by observing whether the original device exposes a header to upper
layers, similar to the logic done in af_packet.

In addition, skb->mac_len needs to be adjusted after adding the Ethernet
header for the skb_push/pull() surrounding dev_queue_xmit_nit() to work
on these packets.

Fixes: 048939088220 ("vrf: add mac header for tunneled packets when sniffer is attached")
Signed-off-by: Eyal Birger 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller

net: Add l3mdev index to flow struct and avoid oif reset for port devices

2022-03-16T03:20:02+00:00

The fundamental premise of VRF and l3mdev core code is binding a socket
to a device (l3mdev or netdev with an L3 domain) to indicate L3 scope.
Legacy code resets flowi_oif to the l3mdev losing any original port
device binding. Ben (among others) has demonstrated use cases where the
original port device binding is important and needs to be retained.
This patch handles that by adding a new entry to the common flow struct
that can indicate the l3mdev index for later rule and table matching
avoiding the need to reset flowi_oif.

In addition to allowing more use cases that require port device binds,
this patch brings a few datapath simplications:

1. l3mdev_fib_rule_match is only called when walking fib rules and
   always after l3mdev_update_flow. That allows an optimization to bail
   early for non-VRF type uses cases when flowi_l3mdev is not set. Also,
   only that index needs to be checked for the FIB table id.

2. l3mdev_update_flow can be called with flowi_oif set to a l3mdev
   (e.g., VRF) device. By resetting flowi_oif only for this case the
   FLOWI_FLAG_SKIP_NH_OIF flag is not longer needed and can be removed,
   removing several checks in the datapath. The flowi_iif path can be
   simplified to only be called if the it is not loopback (loopback can
   not be assigned to an L3 domain) and the l3mdev index is not already
   set.

3. Avoid another device lookup in the output path when the fib lookup
   returns a reject failure.

Note: 2 functional tests for local traffic with reject fib rules are
updated to reflect the new direct failure at FIB lookup time for ping
rather than the failure on packet path. The current code fails like this:

    HINT: Fails since address on vrf device is out of device scope
    COMMAND: ip netns exec ns-A ping -c1 -w1 -I eth1 172.16.3.1
    ping: Warning: source address might be selected on device other than: eth1
    PING 172.16.3.1 (172.16.3.1) from 172.16.3.1 eth1: 56(84) bytes of data.

    --- 172.16.3.1 ping statistics ---
    1 packets transmitted, 0 received, 100% packet loss, time 0ms

where the test now directly fails:

    HINT: Fails since address on vrf device is out of device scope
    COMMAND: ip netns exec ns-A ping -c1 -w1 -I eth1 172.16.3.1
    ping: connect: No route to host

Signed-off-by: David Ahern 
Tested-by: Ben Greear 
Link: https://lore.kernel.org/r/20220314204551.16369-1-dsahern@kernel.org
Signed-off-by: Jakub Kicinski

net: dev: Makes sure netif_rx() can be invoked in any context.

2022-02-14T13:38:35+00:00

Dave suggested a while ago (eleven years by now) "Let's make netif_rx()
work in all contexts and get rid of netif_rx_ni()". Eric agreed and
pointed out that modern devices should use netif_receive_skb() to avoid
the overhead.
In the meantime someone added another variant, netif_rx_any_context(),
which behaves as suggested.

netif_rx() must be invoked with disabled bottom halves to ensure that
pending softirqs, which were raised within the function, are handled.
netif_rx_ni() can be invoked only from process context (bottom halves
must be enabled) because the function handles pending softirqs without
checking if bottom halves were disabled or not.
netif_rx_any_context() invokes on the former functions by checking
in_interrupts().

netif_rx() could be taught to handle both cases (disabled and enabled
bottom halves) by simply disabling bottom halves while invoking
netif_rx_internal(). The local_bh_enable() invocation will then invoke
pending softirqs only if the BH-disable counter drops to zero.

Eric is concerned about the overhead of BH-disable+enable especially in
regard to the loopback driver. As critical as this driver is, it will
receive a shortcut to avoid the additional overhead which is not needed.

Add a local_bh_disable() section in netif_rx() to ensure softirqs are
handled if needed.
Provide __netif_rx() which does not disable BH and has a lockdep assert
to ensure that interrupts are disabled. Use this shortcut in the
loopback driver and in drivers/net/*.c.
Make netif_rx_ni() and netif_rx_any_context() invoke netif_rx() so they
can be removed once they are no more users left.

Link: https://lkml.kernel.org/r/20100415.020246.218622820.davem@davemloft.net
Signed-off-by: Sebastian Andrzej Siewior 
Reviewed-by: Eric Dumazet 
Reviewed-by: Toke Høiland-Jørgensen 
Signed-off-by: David S. Miller

net: Don't include filter.h from net/sock.h

2021-12-29T16:48:14+00:00

sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.

There's a lot of missing includes this was masking. Primarily
in networking tho, this time.

Signed-off-by: Jakub Kicinski 
Signed-off-by: Alexei Starovoitov 
Acked-by: Marc Kleine-Budde 
Acked-by: Florian Fainelli 
Acked-by: Nikolay Aleksandrov 
Acked-by: Stefano Garzarella 
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-12-09T21:23:02+00:00

No conflicts.

Signed-off-by: Jakub Kicinski