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7286 commits

Author SHA1 Message Date
Zhang Shengju 8dfd329fbc arp: correct return value of arp_rcv
Currently, arp_rcv() always return zero on a packet delivery upcall.

To make its behavior more compliant with the way this API should be
used, this patch changes this to let it return NET_RX_SUCCESS when the
packet is proper handled, and NET_RX_DROP otherwise.

v1->v2:
If sanity check is failed, call kfree_skb() instead of consume_skb(), then
return the correct return value.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-07 14:55:04 -05:00
Eric Engestrom a9d562358b net/ipv4: remove left over dead code
8cc785f6f4 ("net: ipv4: make the ping
/proc code AF-independent") removed the code using it, but renamed this
variable instead of removing it.

Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-02 15:00:55 -05:00
WANG Cong 64d4e3431e net: remove skb_sender_cpu_clear()
After commit 52bd2d62ce ("net: better skb->sender_cpu and skb->napi_id cohabitation")
skb_sender_cpu_clear() becomes empty and can be removed.

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01 17:36:47 -05:00
Deepa Dinamani b1b270d863 net: ipv4: tcp_probe: Replace timespec with timespec64
TCP probe log timestamps use struct timespec which is
not y2038 safe. Even though timespec might be good enough here
as it is used to represent delta time, the plan is to get rid
of all uses of timespec in the kernel.
Replace with struct timespec64 which is y2038 safe.

Prints still use unsigned long format and type.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01 17:18:44 -05:00
Deepa Dinamani 822c868532 net: ipv4: Convert IP network timestamps to be y2038 safe
ICMP timestamp messages and IP source route options require
timestamps to be in milliseconds modulo 24 hours from
midnight UT format.

Add inet_current_timestamp() function to support this. The function
returns the required timestamp in network byte order.

Timestamp calculation is also changed to call ktime_get_real_ts64()
which uses struct timespec64. struct timespec64 is y2038 safe.
Previously it called getnstimeofday() which uses struct timespec.
struct timespec is not y2038 safe.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01 17:18:44 -05:00
Alexander Duyck 2246387662 GSO: Provide software checksum of tunneled UDP fragmentation offload
On reviewing the code I realized that GRE and UDP tunnels could cause a
kernel panic if we used GSO to segment a large UDP frame that was sent
through the tunnel with an outer checksum and hardware offloads were not
available.

In order to correct this we need to update the feature flags that are
passed to the skb_segment function so that in the event of UDP
fragmentation being requested for the inner header the segmentation
function will correctly generate the checksum for the payload if we cannot
segment the outer header.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-26 14:23:35 -05:00
David Lamparter 17b693cdd8 net: l3mdev: prefer VRF master for source address selection
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 <equinox@diac24.net>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
[dsa: Fixed comment style and removed extra blank link ]
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-26 14:22:26 -05:00
David Ahern 3f2fb9a834 net: l3mdev: address selection should only consider devices in L3 domain
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 <david@opensourcerouting.org>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-26 14:22:26 -05:00
Craig Gallek e5fbfc1c2d soreuseport: fix merge conflict in tcp bind
One of the validation checks for the new array-based TCP SO_REUSEPORT
validation was unintentionally dropped in ea8add2b19.  This adds it back.

Lack of this check allows the user to allocate multiple sock_reuseport
structures (leaking all but the first).

Fixes: ea8add2b19 ("tcp/dccp: better use of ephemeral ports in bind()")
Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-24 13:38:18 -05:00
David S. Miller b633353115 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
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 <davem@davemloft.net>
2016-02-23 00:09:14 -05:00
Anton Protopopov a97eb33ff2 rtnl: RTM_GETNETCONF: fix wrong return value
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 <a.s.protopopov@gmail.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-19 15:33:46 -05:00
Jiri Benc d13b161c2c gre: clear IFF_TX_SKB_SHARING
ether_setup sets IFF_TX_SKB_SHARING but this is not supported by gre
as it modifies the skb on xmit.

Also, clean up whitespace in ipgre_tap_setup when we're already touching it.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-18 14:43:48 -05:00
Jiri Benc 7f290c9435 iptunnel: scrub packet in iptunnel_pull_header
Part of skb_scrub_packet was open coded in iptunnel_pull_header. Let it call
skb_scrub_packet directly instead.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-18 14:34:54 -05:00
Eric Dumazet 7716682cc5 tcp/dccp: fix another race at listener dismantle
Ilya reported following lockdep splat:

kernel: =========================
kernel: [ BUG: held lock freed! ]
kernel: 4.5.0-rc1-ceph-00026-g5e0a311 #1 Not tainted
kernel: -------------------------
kernel: swapper/5/0 is freeing memory
ffff880035c9d200-ffff880035c9dbff, with a lock still held there!
kernel: (&(&queue->rskq_lock)->rlock){+.-...}, at:
[<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0
kernel: 4 locks held by swapper/5/0:
kernel: #0:  (rcu_read_lock){......}, at: [<ffffffff8169ef6b>]
netif_receive_skb_internal+0x4b/0x1f0
kernel: #1:  (rcu_read_lock){......}, at: [<ffffffff816e977f>]
ip_local_deliver_finish+0x3f/0x380
kernel: #2:  (slock-AF_INET){+.-...}, at: [<ffffffff81685ffb>]
sk_clone_lock+0x19b/0x440
kernel: #3:  (&(&queue->rskq_lock)->rlock){+.-...}, at:
[<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0

To properly fix this issue, inet_csk_reqsk_queue_add() needs
to return to its callers if the child as been queued
into accept queue.

We also need to make sure listener is still there before
calling sk->sk_data_ready(), by holding a reference on it,
since the reference carried by the child can disappear as
soon as the child is put on accept queue.

Reported-by: Ilya Dryomov <idryomov@gmail.com>
Fixes: ebb516af60 ("tcp/dccp: fix race at listener dismantle phase")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-18 11:35:51 -05:00
Xin Long deed49df73 route: check and remove route cache when we get route
Since the gc of ipv4 route was removed, the route cached would has
no chance to be removed, and even it has been timeout, it still could
be used, cause no code to check it's expires.

Fix this issue by checking  and removing route cache when we get route.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-18 11:31:36 -05:00
Insu Yun 1eea84b74c tcp: correctly crypto_alloc_hash return check
crypto_alloc_hash never returns NULL

Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-17 22:23:04 -05:00
Ben Hutchings 7bbf3cae65 ipv4: Remove inet_lro library
There are no longer any in-tree drivers that use it.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-17 16:15:46 -05:00
Nikolay Borisov 52a773d645 net: Export ip fragment sysctl to unprivileged users
Now that all the ip fragmentation related sysctls are namespaceified
there is no reason to hide them anymore from "root" users inside
containers.

Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:42:54 -05:00
Nikolay Borisov 0fbf4cb27e ipv4: namespacify ip fragment max dist sysctl knob
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:42:54 -05:00
Nikolay Borisov e21145a987 ipv4: namespacify ip_early_demux sysctl knob
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:42:54 -05:00
Nikolay Borisov 287b7f38fd ipv4: Namespacify ip_dynaddr sysctl knob
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:42:54 -05:00
Nikolay Borisov dcd87999d4 igmp: net: Move igmp namespace init to correct file
When igmp related sysctl were namespacified their initializatin was
erroneously put into the tcp socket namespace constructor. This
patch moves the relevant code into the igmp namespace constructor to
keep things consistent.

Also sprinkle some #ifdefs to silence warnings

Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:42:54 -05:00
Nikolay Borisov fa50d974d1 ipv4: Namespaceify ip_default_ttl sysctl knob
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:42:54 -05:00
Eric Dumazet cd9b266095 tcp: add tcpi_min_rtt and tcpi_notsent_bytes to tcp_info
tcpi_min_rtt reports the minimal rtt observed by TCP stack for the flow,
in usec unit. Might be ~0U if not yet known.

tcpi_notsent_bytes reports the amount of bytes in the write queue that
were not yet sent.

This is done in a single patch to not add a temporary 32bit padding hole
in tcp_info.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:27:35 -05:00
Eric Dumazet 729235554d tcp: md5: release request socket instead of listener
If tcp_v4_inbound_md5_hash() returns an error, we must release
the refcount on the request socket, not on the listener.

The bug was added for IPv4 only.

Fixes: 079096f103 ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:24:06 -05:00
Paolo Abeni 3c1cb4d260 net/ipv4: add dst cache support for gre lwtunnels
In case of UDP traffic with datagram length below MTU this
gives about 4% performance increase

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Suggested-and-Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:21:49 -05:00
Paolo Abeni e09acddf87 ip_tunnel: replace dst_cache with generic implementation
The current ip_tunnel cache implementation is prone to a race
that will cause the wrong dst to be cached on cuncurrent dst cache
miss and ip tunnel update via netlink.

Replacing with the generic implementation fix the issue.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Suggested-and-acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:21:48 -05:00
Eric Dumazet 372022830b tcp: do not set rtt_min to 1
There are some cases where rtt_us derives from deltas of jiffies,
instead of using usec timestamps.

Since we want to track minimal rtt, better to assume a delta of 0 jiffie
might be in fact be very close to 1 jiffie.

It is kind of sad jiffies_to_usecs(1) calls a function instead of simply
using a constant.

Fixes: f672258391 ("tcp: track min RTT using windowed min-filter")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 16:07:13 -05:00
Eric Dumazet 919483096b ipv4: fix memory leaks in ip_cmsg_send() callers
Dmitry reported memory leaks of IP options allocated in
ip_cmsg_send() when/if this function returns an error.

Callers are responsible for the freeing.

Many thanks to Dmitry for the report and diagnostic.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-13 05:57:39 -05:00
Edward Cree 6fa79666e2 net: ip_tunnel: remove 'csum_help' argument to iptunnel_handle_offloads
All users now pass false, so we can remove it, and remove the code that
 was conditional upon it.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-12 05:52:16 -05:00
Edward Cree 53936107ba net: gre: Implement LCO for GRE over IPv4
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-12 05:52:16 -05:00
Edward Cree 06f622926d fou: enable LCO in FOU and GUE
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-12 05:52:16 -05:00
Edward Cree d75f1306d9 net: udp: always set up for CHECKSUM_PARTIAL offload
If the dst device doesn't support it, it'll get fixed up later anyway
 by validate_xmit_skb().  Also, this allows us to take advantage of LCO
 to avoid summing the payload multiple times.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-12 05:52:15 -05:00
Edward Cree 179bc67f69 net: local checksum offload for encapsulation
The arithmetic properties of the ones-complement checksum mean that a
 correctly checksummed inner packet, including its checksum, has a ones
 complement sum depending only on whatever value was used to initialise
 the checksum field before checksumming (in the case of TCP and UDP,
 this is the ones complement sum of the pseudo header, complemented).
Consequently, if we are going to offload the inner checksum with
 CHECKSUM_PARTIAL, we can compute the outer checksum based only on the
 packed data not covered by the inner checksum, and the initial value of
 the inner checksum field.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-12 05:52:15 -05:00
Eric Dumazet ea8add2b19 tcp/dccp: better use of ephemeral ports in bind()
Implement strategy used in __inet_hash_connect() in opposite way :

Try to find a candidate using odd ports, then fallback to even ports.

We no longer disable BH for whole traversal, but one bucket at a time.
We also use cond_resched() to yield cpu to other tasks if needed.

I removed one indentation level and tried to mirror the loop we have
in __inet_hash_connect() and variable names to ease code maintenance.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-12 05:28:32 -05:00
Eric Dumazet 1580ab63fc tcp/dccp: better use of ephemeral ports in connect()
In commit 07f4c90062 ("tcp/dccp: try to not exhaust ip_local_port_range
in connect()"), I added a very simple heuristic, so that we got better
chances to use even ports, and allow bind() users to have more available
slots.

It gave nice results, but with more than 200,000 TCP sessions on a typical
server, the ~30,000 ephemeral ports are still a rare resource.

I chose to go a step further, by looking at all even ports, and if none
was available, fallback to odd ports.

The companion patch does the same in bind(), but in opposite way.

I've seen exec times of up to 30ms on busy servers, so I no longer
disable BH for the whole traversal, but only for each hash bucket.
I also call cond_resched() to be gentle to other tasks.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-12 05:28:32 -05:00
Nikolay Borisov 165094afce igmp: Namespacify igmp_qrv sysctl knob
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 09:59:22 -05:00
Nikolay Borisov 87a8a2ae65 igmp: Namespaceify igmp_llm_reports sysctl knob
This was initially introduced in df2cf4a78e ("IGMP: Inhibit
reports for local multicast groups") by defining the sysctl in the
ipv4_net_table array, however it was never implemented to be
namespace aware. Fix this by changing the code accordingly.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 09:59:22 -05:00
Nikolay Borisov 166b6b2d6f igmp: Namespaceify igmp_max_msf sysctl knob
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 09:59:22 -05:00
Nikolay Borisov 815c527007 igmp: Namespaceify igmp_max_memberships sysctl knob
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 09:59:22 -05:00
Alexander Duyck dbef491ebe udp: Use uh->len instead of skb->len to compute checksum in segmentation
The segmentation code was having to do a bunch of work to pull the
skb->len and strip the udp header offset before the value could be used to
adjust the checksum.  Instead of doing all this work we can just use the
value that goes into uh->len since that is the correct value with the
correct byte order that we need anyway.  By using this value we can save
ourselves a bunch of pain as there is no need to do multiple byte swaps.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 08:55:34 -05:00
Alexander Duyck fdaefd62fd udp: Clean up the use of flags in UDP segmentation offload
This patch goes though and cleans up the logic related to several of the
control flags used in UDP segmentation.  Specifically the use of dont_encap
isn't really needed as we can just check the skb for CHECKSUM_PARTIAL and
if it isn't set then we don't need to update the internal headers.  As such
we can just drop that value.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 08:55:34 -05:00
Alexander Duyck 3872035241 gre: Use inner_proto to obtain inner header protocol
Instead of parsing headers to determine the inner protocol we can just pull
the value from inner_proto.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 08:55:34 -05:00
Alexander Duyck 2e598af713 gre: Use GSO flags to determine csum need instead of GRE flags
This patch updates the gre checksum path to follow something much closer to
the UDP checksum path.  By doing this we can avoid needing to do as much
header inspection and can just make use of the fields we were already
reading in the sk_buff structure.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 08:55:34 -05:00
Alexander Duyck ddff00d420 net: Move skb_has_shared_frag check out of GRE code and into segmentation
The call skb_has_shared_frag is used in the GRE path and skb_checksum_help
to verify that no frags can be modified by an external entity.  This check
really doesn't belong in the GRE path but in the skb_segment function
itself.  This way any protocol that might be segmented will be performing
this check before attempting to offload a checksum to software.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 08:55:34 -05:00
Alexander Duyck 08b64fcca9 net: Store checksum result for offloaded GSO checksums
This patch makes it so that we can offload the checksums for a packet up
to a certain point and then begin computing the checksums via software.
Setting this up is fairly straight forward as all we need to do is reset
the values stored in csum and csum_start for the GSO context block.

One complication for this is remote checksum offload.  In order to allow
the inner checksums to be offloaded while computing the outer checksum
manually we needed to have some way of indicating that the offload wasn't
real.  In order to do that I replaced CHECKSUM_PARTIAL with
CHECKSUM_UNNECESSARY in the case of us computing checksums for the outer
header while skipping computing checksums for the inner headers.  We clean
up the ip_summed flag and set it to either CHECKSUM_PARTIAL or
CHECKSUM_NONE once we hand the packet off to the next lower level.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 08:55:33 -05:00
Alexander Duyck 7fbeffed77 net: Update remote checksum segmentation to support use of GSO checksum
This patch addresses two main issues.

First in the case of remote checksum offload we were avoiding dealing with
scatter-gather issues.  As a result it would be possible to assemble a
series of frames that used frags instead of being linearized as they should
have if remote checksum offload was enabled.

Second I have updated the code so that we now let GSO take care of doing
the checksum on the data itself and drop the special case that was added
for remote checksum offload.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 08:55:33 -05:00
Alexander Duyck bef3c6c937 net: Drop unecessary enc_features variable from tunnel segmentation functions
The enc_features variable isn't necessary since features isn't used
anywhere after we create enc_features so instead just use a destructive AND
on features itself and save ourselves the variable declaration.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 08:55:33 -05:00
Johannes Berg 97daf33145 ipv4: add option to drop gratuitous ARP packets
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 <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 04:27:35 -05:00
Johannes Berg 12b74dfadb ipv4: add option to drop unicast encapsulated in L2 multicast
In order to solve a problem with 802.11, the so-called hole-196 attack,
add an option (sysctl) called "drop_unicast_in_l2_multicast" which, if
enabled, causes the stack to drop IPv4 unicast packets encapsulated in
link-layer multi- or broadcast frames. Such frames can (as an attack)
be created by any member of the same wireless network and transmitted
as valid encrypted frames since the symmetric key for broadcast frames
is shared between all stations.

Additionally, enabling this option provides compliance with a SHOULD
clause of RFC 1122.

Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 04:27:35 -05:00