linux-stable.git/net/ipv6, branch v3.18.10

net: ping: Return EAFNOSUPPORT when appropriate.

2015-03-14T19:37:14+00:00

[ Upstream commit 9145736d4862145684009d6a72a6e61324a9439e ]

1. For an IPv4 ping socket, ping_check_bind_addr does not check
   the family of the socket address that's passed in. Instead,
   make it behave like inet_bind, which enforces either that the
   address family is AF_INET, or that the family is AF_UNSPEC and
   the address is 0.0.0.0.
2. For an IPv6 ping socket, ping_check_bind_addr returns EINVAL
   if the socket family is not AF_INET6. Return EAFNOSUPPORT
   instead, for consistency with inet6_bind.
3. Make ping_v4_sendmsg and ping_v6_sendmsg return EAFNOSUPPORT
   instead of EINVAL if an incorrect socket address structure is
   passed in.
4. Make IPv6 ping sockets be IPv6-only. The code does not support
   IPv4, and it cannot easily be made to support IPv4 because
   the protocol numbers for ICMP and ICMPv6 are different. This
   makes connect(::ffff:192.0.2.1) fail with EAFNOSUPPORT instead
   of making the socket unusable.

Among other things, this fixes an oops that can be triggered by:

    int s = socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP);
    struct sockaddr_in6 sin6 = {
        .sin6_family = AF_INET6,
        .sin6_addr = in6addr_any,
    };
    bind(s, (struct sockaddr *) &sin6, sizeof(sin6));

Change-Id: If06ca86d9f1e4593c0d6df174caca3487c57a241
Signed-off-by: Lorenzo Colitti 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

udp: only allow UFO for packets from SOCK_DGRAM sockets

2015-03-14T19:37:14+00:00

[ Upstream commit acf8dd0a9d0b9e4cdb597c2f74802f79c699e802 ]

If an over-MTU UDP datagram is sent through a SOCK_RAW socket to a
UFO-capable device, ip_ufo_append_data() sets skb->ip_summed to
CHECKSUM_PARTIAL unconditionally as all GSO code assumes transport layer
checksum is to be computed on segmentation. However, in this case,
skb->csum_start and skb->csum_offset are never set as raw socket
transmit path bypasses udp_send_skb() where they are usually set. As a
result, driver may access invalid memory when trying to calculate the
checksum and store the result (as observed in virtio_net driver).

Moreover, the very idea of modifying the userspace provided UDP header
is IMHO against raw socket semantics (I wasn't able to find a document
clearly stating this or the opposite, though). And while allowing
CHECKSUM_NONE in the UFO case would be more efficient, it would be a bit
too intrusive change just to handle a corner case like this. Therefore
disallowing UFO for packets from SOCK_DGRAM seems to be the best option.

Signed-off-by: Michal Kubecek 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

ipv6: fix ipv6_cow_metrics for non DST_HOST case

2015-03-14T19:37:10+00:00

[ Upstream commit 3b4711757d7903ab6fa88a9e7ab8901b8227da60 ]

ipv6_cow_metrics() currently assumes only DST_HOST routes require
dynamic metrics allocation from inetpeer.  The assumption breaks
when ndisc discovered router with RTAX_MTU and RTAX_HOPLIMIT metric.
Refer to ndisc_router_discovery() in ndisc.c and note that dst_metric_set()
is called after the route is created.

This patch creates the metrics array (by calling dst_cow_metrics_generic) in
ipv6_cow_metrics().

Test:
radvd.conf:
interface qemubr0
{
	AdvLinkMTU 1300;
	AdvCurHopLimit 30;

	prefix fd00:face:face:face::/64
	{
		AdvOnLink on;
		AdvAutonomous on;
		AdvRouterAddr off;
	};
};

Before:
[root@qemu1 ~]# ip -6 r show | egrep -v unreachable
fd00:face:face:face::/64 dev eth0  proto kernel  metric 256  expires 27sec
fe80::/64 dev eth0  proto kernel  metric 256
default via fe80::74df:d0ff:fe23:8ef2 dev eth0  proto ra  metric 1024  expires 27sec

After:
[root@qemu1 ~]# ip -6 r show | egrep -v unreachable
fd00:face:face:face::/64 dev eth0  proto kernel  metric 256  expires 27sec mtu 1300
fe80::/64 dev eth0  proto kernel  metric 256  mtu 1300
default via fe80::74df:d0ff:fe23:8ef2 dev eth0  proto ra  metric 1024  expires 27sec mtu 1300 hoplimit 30

Fixes: 8e2ec639173f325 (ipv6: don't use inetpeer to store metrics for routes.)
Signed-off-by: Martin KaFai Lau 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

ipv6: addrconf: add missing validate_link_af handler

2015-03-14T19:37:09+00:00

[ Upstream commit 11b1f8288d4341af5d755281c871bff6c3e270dd ]

We still need a validate_link_af() handler with an appropriate nla policy,
similarly as we have in IPv4 case, otherwise size validations are not being
done properly in that case.

Fixes: f53adae4eae5 ("net: ipv6: add tokenized interface identifier support")
Fixes: bc91b0f07ada ("ipv6: addrconf: implement address generation modes")
Cc: Jiri Pirko 
Signed-off-by: Daniel Borkmann 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

ipv6: replacing a rt6_info needs to purge possible propagated rt6_infos too

2015-02-27T01:49:01+00:00

[ Upstream commit 6e9e16e6143b725662e47026a1d0f270721cdd24 ]

Lubomir Rintel reported that during replacing a route the interface
reference counter isn't correctly decremented.

To quote bug :
| [root@rhel7-5 lkundrak]# sh -x lal
| + ip link add dev0 type dummy
| + ip link set dev0 up
| + ip link add dev1 type dummy
| + ip link set dev1 up
| + ip addr add 2001:db8:8086::2/64 dev dev0
| + ip route add 2001:db8:8086::/48 dev dev0 proto static metric 20
| + ip route add 2001:db8:8088::/48 dev dev1 proto static metric 10
| + ip route replace 2001:db8:8086::/48 dev dev1 proto static metric 20
| + ip link del dev0 type dummy
| Message from syslogd@rhel7-5 at Jan 23 10:54:41 ...
|  kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2
|
| Message from syslogd@rhel7-5 at Jan 23 10:54:51 ...
|  kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2

During replacement of a rt6_info we must walk all parent nodes and check
if the to be replaced rt6_info got propagated. If so, replace it with
an alive one.

Fixes: 4a287eba2de3957 ("IPv6 routing, NLM_F_* flag support: REPLACE and EXCL flags support, warn about missing CREATE flag")
Reported-by: Lubomir Rintel 
Signed-off-by: Hannes Frederic Sowa 
Tested-by: Lubomir Rintel 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: stop sending PTB packets for MTU < 1280

2015-02-27T01:49:00+00:00

[ Upstream commit 9d289715eb5c252ae15bd547cb252ca547a3c4f2 ]

Reduce the attack vector and stop generating IPv6 Fragment Header for
paths with an MTU smaller than the minimum required IPv6 MTU
size (1280 byte) - called atomic fragments.

See IETF I-D "Deprecating the Generation of IPv6 Atomic Fragments" [1]
for more information and how this "feature" can be misused.

[1] https://tools.ietf.org/html/draft-ietf-6man-deprecate-atomfrag-generation-00

Signed-off-by: Fernando Gont 
Signed-off-by: Hagen Paul Pfeifer 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ip: zero sockaddr returned on error queue

2015-02-27T01:49:00+00:00

[ Upstream commit f812116b174e59a350acc8e4856213a166a91222 ]

The sockaddr is returned in IP(V6)_RECVERR as part of errhdr. That
structure is defined and allocated on the stack as

    struct {
            struct sock_extended_err ee;
            struct sockaddr_in(6)    offender;
    } errhdr;

The second part is only initialized for certain SO_EE_ORIGIN values.
Always initialize it completely.

An MTU exceeded error on a SOCK_RAW/IPPROTO_RAW is one example that
would return uninitialized bytes.

Signed-off-by: Willem de Bruijn 

----

Also verified that there is no padding between errhdr.ee and
errhdr.offender that could leak additional kernel data.
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp6: don't move IP6CB before xfrm6_policy_check()

2015-01-27T16:29:33+00:00

[ Upstream commit 2dc49d1680b534877fd20cce52557ea542bb06b6 ]

When xfrm6_policy_check() is used, _decode_session6() is called after some
intermediate functions. This function uses IP6CB(), thus TCP_SKB_CB() must be
prepared after the call of xfrm6_policy_check().

Before this patch, scenarii with IPv6 + TCP + IPsec Transport are broken.

Fixes: 971f10eca186 ("tcp: better TCP_SKB_CB layout to reduce cache line misses")
Reported-by: Huaibin Wang 
Suggested-by: Eric Dumazet 
Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp: fix more NULL deref after prequeue changes

2014-12-16T17:39:05+00:00

[ Upstream commit 0f85feae6b710ced3abad5b2b47d31dfcb956b62 ]

When I cooked commit c3658e8d0f1 ("tcp: fix possible NULL dereference in
tcp_vX_send_reset()") I missed other spots we could deref a NULL
skb_dst(skb)

Again, if a socket is provided, we do not need skb_dst() to get a
pointer to network namespace : sock_net(sk) is good enough.

Reported-by: Dann Frazier 
Bisected-by: Dann Frazier 
Tested-by: Dann Frazier 
Signed-off-by: Eric Dumazet 
Fixes: ca777eff51f7 ("tcp: remove dst refcount false sharing for prequeue mode")
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp: fix possible NULL dereference in tcp_vX_send_reset()

2014-11-25T19:29:18+00:00

After commit ca777eff51f7 ("tcp: remove dst refcount false sharing for
prequeue mode") we have to relax check against skb dst in
tcp_v[46]_send_reset() if prequeue dropped the dst.

If a socket is provided, a full lookup was done to find this socket,
so the dst test can be skipped.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88191
Reported-by: Jaša Bartelj 
Signed-off-by: Eric Dumazet 
Reported-by: Daniel Borkmann 
Fixes: ca777eff51f7 ("tcp: remove dst refcount false sharing for prequeue mode")
Signed-off-by: David S. Miller