linux-toradex.git/net/ipv4/devinet.c, branch v4.9.119

ipv4: igmp: guard against silly MTU values

2018-01-02T19:35:10+00:00

[ Upstream commit b5476022bbada3764609368f03329ca287528dc8 ]

IPv4 stack reacts to changes to small MTU, by disabling itself under
RTNL.

But there is a window where threads not using RTNL can see a wrong
device mtu. This can lead to surprises, in igmp code where it is
assumed the mtu is suitable.

Fix this by reading device mtu once and checking IPv4 minimal MTU.

This patch adds missing IPV4_MIN_MTU define, to not abuse
ETH_MIN_MTU anymore.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netconf: add a notif when settings are created

2016-09-01T22:18:08+00:00

All changes are notified, but the initial state was missing.

Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller

ipv4: do not abuse GFP_ATOMIC in inet_netconf_notify_devconf()

2016-07-09T22:12:25+00:00

inet_forward_change() runs with RTNL held.
We are allowed to sleep if required.

If we use __in_dev_get_rtnl() instead of __in_dev_get_rcu(),
we no longer have to use GFP_ATOMIC allocations in
inet_netconf_notify_devconf(), meaning we are less likely to miss
notifications under memory pressure, and wont touch precious memory
reserves either and risk dropping incoming packets.

inet_netconf_get_devconf() can also use GFP_KERNEL allocation.

Fixes: edc9e748934c ("rtnl/ipv4: use netconf msg to advertise forwarding status")
Fixes: 9e5511106f99 ("rtnl/ipv4: add support of RTM_GETNETCONF")
Signed-off-by: Eric Dumazet 
Cc: Nicolas Dichtel 
Acked-by: Nicolas Dichtel 
Signed-off-by: David S. Miller

ipv4: Don't do expensive useless work during inetdev destroy.

2016-03-14T03:28:35+00:00

When an inetdev is destroyed, every address assigned to the interface
is removed.  And in this scenerio we do two pointless things which can
be very expensive if the number of assigned interfaces is large:

1) Address promotion.  We are deleting all addresses, so there is no
   point in doing this.

2) A full nf conntrack table purge for every address.  We only need to
   do this once, as is already caught by the existing
   masq_dev_notifier so masq_inet_event() can skip this.

Reported-by: Solar Designer 
Signed-off-by: David S. Miller 
Tested-by: Cyrill Gorcunov

netconf: add macro to represent all attributes

2016-03-14T01:54:44+00:00

This patch adds macro NETCONFA_ALL to represent all type of netconf
attributes for IPv4 and IPv6.

Signed-off-by: Zhang Shengju 
Signed-off-by: David S. Miller

net: l3mdev: prefer VRF master for source address selection

2016-02-26T19:22:26+00:00

When selecting an address in context of a VRF, the vrf master should be
preferred for address selection.  If it isn't, the user has a hard time
getting the system to select to their preference - the code will pick
the address off the first in-VRF interface it can find, which on a
router could well be a non-routable address.

Signed-off-by: David Lamparter 
Signed-off-by: David Ahern 
[dsa: Fixed comment style and removed extra blank link ]
Signed-off-by: David S. Miller

net: l3mdev: address selection should only consider devices in L3 domain

2016-02-26T19:22:26+00:00

David Lamparter noted a use case where the source address selection fails
to pick an address from a VRF interface - unnumbered interfaces.

Relevant commands from his script:
    ip addr add 9.9.9.9/32 dev lo
    ip link set lo up

    ip link add name vrf0 type vrf table 101
    ip rule add oif vrf0 table 101
    ip rule add iif vrf0 table 101
    ip link set vrf0 up
    ip addr add 10.0.0.3/32 dev vrf0

    ip link add name dummy2 type dummy
    ip link set dummy2 master vrf0 up

    --> note dummy2 has no address - unnumbered device

    ip route add 10.2.2.2/32 dev dummy2 table 101
    ip neigh add 10.2.2.2 dev dummy2 lladdr 02:00:00:00:00:02

    tcpdump -ni dummy2 &

And using ping instead of his socat example:
    $ ping -I vrf0 -c1 10.2.2.2
    ping: Warning: source address might be selected on device other than vrf0.
    PING 10.2.2.2 (10.2.2.2) from 9.9.9.9 vrf0: 56(84) bytes of data.

>From tcpdump:
    12:57:29.449128 IP 9.9.9.9 > 10.2.2.2: ICMP echo request, id 2491, seq 1, length 64

Note the source address is from lo and is not a VRF local address. With
this patch:

    $ ping -I vrf0 -c1 10.2.2.2
    PING 10.2.2.2 (10.2.2.2) from 10.0.0.3 vrf0: 56(84) bytes of data.

>From tcpdump:
    12:59:25.096426 IP 10.0.0.3 > 10.2.2.2: ICMP echo request, id 2113, seq 1, length 64

Now the source address comes from vrf0.

The ipv4 function for selecting source address takes a const argument.
Removing the const requires touching a lot of places, so instead
l3mdev_master_ifindex_rcu is changed to take a const argument and then
do the typecast to non-const as required by netdev_master_upper_dev_get_rcu.
This is similar to what l3mdev_fib_table_rcu does.

IPv6 for unnumbered interfaces appears to be selecting the addresses
properly.

Cc: David Lamparter 
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

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

2016-02-23T05:09:14+00:00

Conflicts:
	drivers/net/phy/bcm7xxx.c
	drivers/net/phy/marvell.c
	drivers/net/vxlan.c

All three conflicts were cases of simple overlapping changes.

Signed-off-by: David S. Miller

rtnl: RTM_GETNETCONF: fix wrong return value

2016-02-19T20:33:46+00:00

An error response from a RTM_GETNETCONF request can return the positive
error value EINVAL in the struct nlmsgerr that can mislead userspace.

Signed-off-by: Anton Protopopov 
Acked-by: Cong Wang 
Signed-off-by: David S. Miller

ipv4: add option to drop gratuitous ARP packets

2016-02-11T09:27:35+00:00

In certain 802.11 wireless deployments, there will be ARP proxies
that use knowledge of the network to correctly answer requests.
To prevent gratuitous ARP frames on the shared medium from being
a problem, on such deployments wireless needs to drop them.

Enable this by providing an option called "drop_gratuitous_arp".

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller