linux-toradex.git/net/ipv6, branch v3.4.71

inet: fix possible memory corruption with UDP_CORK and UFO

2013-11-04T12:23:41+00:00

[ This is a simplified -stable version of a set of upstream commits. ]

This is a replacement patch only for stable which does fix the problems
handled by the following two commits in -net:

"ip_output: do skb ufo init for peeked non ufo skb as well" (e93b7d748be887cd7639b113ba7d7ef792a7efb9)
"ip6_output: do skb ufo init for peeked non ufo skb as well" (c547dbf55d5f8cf615ccc0e7265e98db27d3fb8b)

Three frames are written on a corked udp socket for which the output
netdevice has UFO enabled.  If the first and third frame are smaller than
the mtu and the second one is bigger, we enqueue the second frame with
skb_append_datato_frags without initializing the gso fields. This leads
to the third frame appended regulary and thus constructing an invalid skb.

This fixes the problem by always using skb_append_datato_frags as soon
as the first frag got enqueued to the skb without marking the packet
as SKB_GSO_UDP.

The problem with only two frames for ipv6 was fixed by "ipv6: udp
packets following an UFO enqueued packet need also be handled by UFO"
(2811ebac2521ceac84f2bdae402455baa6a7fb47).

Cc: Jiri Pirko 
Cc: Eric Dumazet 
Cc: David Miller 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: Greg Kroah-Hartman

ipv6: restrict neighbor entry creation to output flow

2013-11-04T12:23:40+00:00

This patch is based on 3.2.y branch, the one used by reporter. Please let me
know if it should be different. Thanks.

The patch which introduced the regression was applied on stables:
3.0.64 3.4.31 3.7.8 3.2.39

The patch which introduced the regression was for stable trees only.

---8<---

Commit 0d6a77079c475033cb622c07c5a880b392ef664e "ipv6: do not create
neighbor entries for local delivery" introduced a regression on
which routes to local delivery would not work anymore. Like this:

    $ ip -6 route add local 2001::/64 dev lo
    $ ping6 -c1 2001::9
    PING 2001::9(2001::9) 56 data bytes
    ping: sendmsg: Invalid argument

As this is a local delivery, that commit would not allow the creation of a
neighbor entry and thus the packet cannot be sent.

But as TPROXY scenario actually needs to avoid the neighbor entry creation only
for input flow, this patch now limits previous patch to input flow, keeping
output as before that patch.

Reported-by: Debabrata Banerjee 
Signed-off-by: Marcelo Ricardo Leitner 
Signed-off-by: Jiri Pirko 
Acked-by: Hannes Frederic Sowa 
CC: Hannes Frederic Sowa 
Signed-off-by: Greg Kroah-Hartman

net: do not call sock_put() on TIMEWAIT sockets

2013-11-04T12:23:40+00:00

[ Upstream commit 80ad1d61e72d626e30ebe8529a0455e660ca4693 ]

commit 3ab5aee7fe84 ("net: Convert TCP & DCCP hash tables to use RCU /
hlist_nulls") incorrectly used sock_put() on TIMEWAIT sockets.

We should instead use inet_twsk_put()

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

ipv6 mcast: use in6_dev_put in timer handlers instead of __in6_dev_put

2013-10-13T22:42:48+00:00

[ Upstream commit 9260d3e1013701aa814d10c8fc6a9f92bd17d643 ]

It is possible for the timer handlers to run after the call to
ipv6_mc_down so use in6_dev_put instead of __in6_dev_put in the
handler function in order to do proper cleanup when the refcnt
reaches 0. Otherwise, the refcnt can reach zero without the
inet6_dev being destroyed and we end up leaking a reference to
the net_device and see messages like the following,

unregister_netdevice: waiting for eth0 to become free. Usage count = 1

Tested on linux-3.4.43.

Signed-off-by: Salam Noureddine 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: udp packets following an UFO enqueued packet need also be handled by UFO

2013-10-13T22:42:48+00:00

[ Upstream commit 2811ebac2521ceac84f2bdae402455baa6a7fb47 ]

In the following scenario the socket is corked:
If the first UDP packet is larger then the mtu we try to append it to the
write queue via ip6_ufo_append_data. A following packet, which is smaller
than the mtu would be appended to the already queued up gso-skb via
plain ip6_append_data. This causes random memory corruptions.

In ip6_ufo_append_data we also have to be careful to not queue up the
same skb multiple times. So setup the gso frame only when no first skb
is available.

This also fixes a shortcoming where we add the current packet's length to
cork->length but return early because of a packet > mtu with dontfrag set
(instead of sutracting it again).

Found with trinity.

Cc: YOSHIFUJI Hideaki 
Signed-off-by: Hannes Frederic Sowa 
Reported-by: Dmitry Vyukov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: ipv6: tcp: fix potential use after free in tcp_v6_do_rcv

2013-09-14T13:02:10+00:00

[ Upstream commit 3a1c756590633c0e86df606e5c618c190926a0df ]

In tcp_v6_do_rcv() code, when processing pkt options, we soley work
on our skb clone opt_skb that we've created earlier before entering
tcp_rcv_established() on our way. However, only in condition ...

  if (np->rxopt.bits.rxtclass)
    np->rcv_tclass = ipv6_get_dsfield(ipv6_hdr(skb));

... we work on skb itself. As we extract every other information out
of opt_skb in ipv6_pktoptions path, this seems wrong, since skb can
already be released by tcp_rcv_established() earlier on. When we try
to access it in ipv6_hdr(), we will dereference freed skb.

[ Bug added by commit 4c507d2897bd9b ("net: implement IP_RECVTOS for
  IP_PKTOPTIONS") ]

Signed-off-by: Daniel Borkmann 
Cc: Eric Dumazet 
Acked-by: Eric Dumazet 
Acked-by: Jiri Benc 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ICMPv6: treat dest unreachable codes 5 and 6 as EACCES, not EPROTO

2013-09-14T13:02:10+00:00

[ Upstream commit 61e76b178dbe7145e8d6afa84bb4ccea71918994 ]

RFC 4443 has defined two additional codes for ICMPv6 type 1 (destination
unreachable) messages:
        5 - Source address failed ingress/egress policy
	6 - Reject route to destination

Now they are treated as protocol error and icmpv6_err_convert() converts them
to EPROTO.

RFC 4443 says:
	"Codes 5 and 6 are more informative subsets of code 1."

Treat codes 5 and 6 as code 1 (EACCES)

Btw, connect() returning -EPROTO confuses firefox, so that fallback to
other/IPv4 addresses does not work:
https://bugzilla.mozilla.org/show_bug.cgi?id=910773

Signed-off-by: Jiri Bohac 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: Don't depend on per socket memory for neighbour discovery messages

2013-09-14T13:02:10+00:00

[ Upstream commit 25a6e6b84fba601eff7c28d30da8ad7cfbef0d43 ]

Allocating skbs when sending out neighbour discovery messages
currently uses sock_alloc_send_skb() based on a per net namespace
socket and thus share a socket wmem buffer space.

If a netdevice is temporarily unable to transmit due to carrier
loss or for other reasons, the queued up ndisc messages will cosnume
all of the wmem space and will thus prevent from any more skbs to
be allocated even for netdevices that are able to transmit packets.

The number of neighbour discovery messages sent is very limited,
use of alloc_skb() bypasses the socket wmem buffer size enforcement
while the manual call to skb_set_owner_w() maintains the socket
reference needed for the IPv6 output path.

This patch has orginally been posted by Eric Dumazet in a modified
form.

Signed-off-by: Thomas Graf 
Cc: Eric Dumazet 
Cc: Hannes Frederic Sowa 
Cc: Stephen Warren 
Cc: Fabio Estevam 
Tested-by: Fabio Estevam 
Tested-by: Stephen Warren 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: drop packets with multiple fragmentation headers

2013-09-14T13:02:10+00:00

[ Upstream commit f46078cfcd77fa5165bf849f5e568a7ac5fa569c ]

It is not allowed for an ipv6 packet to contain multiple fragmentation
headers. So discard packets which were already reassembled by
fragmentation logic and send back a parameter problem icmp.

The updates for RFC 6980 will come in later, I have to do a bit more
research here.

Cc: YOSHIFUJI Hideaki 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: remove max_addresses check from ipv6_create_tempaddr

2013-09-14T13:02:09+00:00

[ Upstream commit 4b08a8f1bd8cb4541c93ec170027b4d0782dab52 ]

Because of the max_addresses check attackers were able to disable privacy
extensions on an interface by creating enough autoconfigured addresses:



But the check is not actually needed: max_addresses protects the
kernel to install too many ipv6 addresses on an interface and guards
addrconf_prefix_rcv to install further addresses as soon as this limit
is reached. We only generate temporary addresses in direct response of
a new address showing up. As soon as we filled up the maximum number of
addresses of an interface, we stop installing more addresses and thus
also stop generating more temp addresses.

Even if the attacker tries to generate a lot of temporary addresses
by announcing a prefix and removing it again (lifetime == 0) we won't
install more temp addresses, because the temporary addresses do count
to the maximum number of addresses, thus we would stop installing new
autoconfigured addresses when the limit is reached.

This patch fixes CVE-2013-0343 (but other layer-2 attacks are still
possible).

Thanks to Ding Tianhong to bring this topic up again.

Signed-off-by: Hannes Frederic Sowa 
Cc: Ding Tianhong 
Cc: George Kargiotakis 
Cc: P J P 
Cc: YOSHIFUJI Hideaki 
Acked-by: Ding Tianhong 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman