linux-toradex.git/net/netfilter, branch v3.12.27

inetpeer: get rid of ip_id_count

2014-08-19T15:15:00+00:00

[ Upstream commit 73f156a6e8c1074ac6327e0abd1169e95eb66463 ]

Ideally, we would need to generate IP ID using a per destination IP
generator.

linux kernels used inet_peer cache for this purpose, but this had a huge
cost on servers disabling MTU discovery.

1) each inet_peer struct consumes 192 bytes

2) inetpeer cache uses a binary tree of inet_peer structs,
   with a nominal size of ~66000 elements under load.

3) lookups in this tree are hitting a lot of cache lines, as tree depth
   is about 20.

4) If server deals with many tcp flows, we have a high probability of
   not finding the inet_peer, allocating a fresh one, inserting it in
   the tree with same initial ip_id_count, (cf secure_ip_id())

5) We garbage collect inet_peer aggressively.

IP ID generation do not have to be 'perfect'

Goal is trying to avoid duplicates in a short period of time,
so that reassembly units have a chance to complete reassembly of
fragments belonging to one message before receiving other fragments
with a recycled ID.

We simply use an array of generators, and a Jenkin hash using the dst IP
as a key.

ipv6_select_ident() is put back into net/ipv6/ip6_output.c where it
belongs (it is only used from this file)

secure_ip_id() and secure_ipv6_id() no longer are needed.

Rename ip_select_ident_more() to ip_select_ident_segs() to avoid
unnecessary decrement/increment of the number of segments.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Jiri Slaby

ipvs: Fix panic due to non-linear skb

2014-07-17T11:43:20+00:00

commit f44a5f45f544561302e855e7bd104e5f506ec01b upstream.

Receiving a ICMP response to an IPIP packet in a non-linear skb could
cause a kernel panic in __skb_pull.

The problem was introduced in
commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e ("ipvs: implement
passive PMTUD for IPIP packets").

Signed-off-by: Peter Christensen 
Acked-by: Julian Anastasov 
Signed-off-by: Simon Horman 
Signed-off-by: Jiri Slaby

netfilter: nf_nat: fix oops on netns removal

2014-07-16T09:22:53+00:00

[ Upstream commit 945b2b2d259d1a4364a2799e80e8ff32f8c6ee6f ]

Quoting Samu Kallio:

 Basically what's happening is, during netns cleanup,
 nf_nat_net_exit gets called before ipv4_net_exit. As I understand
 it, nf_nat_net_exit is supposed to kill any conntrack entries which
 have NAT context (through nf_ct_iterate_cleanup), but for some
 reason this doesn't happen (perhaps something else is still holding
 refs to those entries?).

 When ipv4_net_exit is called, conntrack entries (including those
 with NAT context) are cleaned up, but the
 nat_bysource hashtable is long gone - freed in nf_nat_net_exit. The
 bug happens when attempting to free a conntrack entry whose NAT hash
 'prev' field points to a slot in the freed hash table (head for that
 bin).

We ignore conntracks with null nat bindings.  But this is wrong,
as these are in bysource hash table as well.

Restore nat-cleaning for the netns-is-being-removed case.

bug:
https://bugzilla.kernel.org/show_bug.cgi?id=65191

Cc:  # 3.15.x
Cc:  # 3.14.x
Cc:  # 3.12.x
Cc:  # 3.10.x
Fixes: c2d421e1718 ('netfilter: nf_nat: fix race when unloading protocol modules')
Reported-by: Samu Kallio 
Debugged-by: Samu Kallio 
Signed-off-by: Florian Westphal 
Tested-by: Samu Kallio 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Jiri Slaby

ipvs: stop tot_stats estimator only under CONFIG_SYSCTL

2014-07-16T09:22:53+00:00

[ Upstream commit 9802d21e7a0b0d2167ef745edc1f4ea7a0fc6ea3 ]

The tot_stats estimator is started only when CONFIG_SYSCTL
is defined. But it is stopped without checking CONFIG_SYSCTL.
Fix the crash by moving ip_vs_stop_estimator into
ip_vs_control_net_cleanup_sysctl.

The change is needed after commit 14e405461e664b
("IPVS: Add __ip_vs_control_{init,cleanup}_sysctl()") from 2.6.39.

Cc:  # 3.15.x
Cc:  # 3.14.x
Cc:  # 3.12.x
Cc:  # 3.10.x
Cc:  # 3.2.x
Reported-by: Jet Chen 
Tested-by: Jet Chen 
Signed-off-by: Julian Anastasov 
Sgned-off-by: Simon Horman 
Signed-off-by: Jiri Slaby

net: Use netlink_ns_capable to verify the permisions of netlink messages

2014-06-23T08:27:57+00:00

[ Upstream commit 90f62cf30a78721641e08737bda787552428061e ]

It is possible by passing a netlink socket to a more privileged
executable and then to fool that executable into writing to the socket
data that happens to be valid netlink message to do something that
privileged executable did not intend to do.

To keep this from happening replace bare capable and ns_capable calls
with netlink_capable, netlink_net_calls and netlink_ns_capable calls.
Which act the same as the previous calls except they verify that the
opener of the socket had the desired permissions as well.

Reported-by: Andy Lutomirski 
Signed-off-by: "Eric W. Biederman" 
Signed-off-by: David S. Miller 
Signed-off-by: Jiri Slaby

netfilter: nf_conntrack_dccp: fix skb_header_pointer API usages

2014-04-03T08:32:31+00:00

commit b22f5126a24b3b2f15448c3f2a254fc10cbc2b92 upstream.

Some occurences in the netfilter tree use skb_header_pointer() in
the following way ...

  struct dccp_hdr _dh, *dh;
  ...
  skb_header_pointer(skb, dataoff, sizeof(_dh), &dh);

... where dh itself is a pointer that is being passed as the copy
buffer. Instead, we need to use &_dh as the forth argument so that
we're copying the data into an actual buffer that sits on the stack.

Currently, we probably could overwrite memory on the stack (e.g.
with a possibly mal-formed DCCP packet), but unintentionally, as
we only want the buffer to be placed into _dh variable.

Fixes: 2bc780499aa3 ("[NETFILTER]: nf_conntrack: add DCCP protocol support")
Signed-off-by: Daniel Borkmann 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Jiri Slaby

ipvs: fix AF assignment in ip_vs_conn_new()

2014-04-03T08:32:21+00:00

commit 2a971354e74f3837d14b9c8d7f7983b0c9c330e4 upstream.

If a fwmark is passed to ip_vs_conn_new(), it is passed in
vaddr, not daddr. Therefore we should set AF to AF_UNSPEC in
vaddr assignment (like we do in ip_vs_ct_in_get()), otherwise we
may copy only first 4 bytes of an IPv6 address into cp->daddr.

Signed-off-by: Bogdano Arendartchuk 
Signed-off-by: Michal Kubecek 
Acked-by: Julian Anastasov 
Signed-off-by: Simon Horman 
Signed-off-by: Jiri Slaby

netfilter: nf_nat: fix access to uninitialized buffer in IRC NAT helper

2014-01-15T23:31:43+00:00

commit 2690d97ade05c5325cbf7c72b94b90d265659886 upstream.

Commit 5901b6be885e attempted to introduce IPv6 support into
IRC NAT helper. By doing so, the following code seemed to be removed
by accident:

  ip = ntohl(exp->master->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3.ip);
  sprintf(buffer, "%u %u", ip, port);
  pr_debug("nf_nat_irc: inserting '%s' == %pI4, port %u\n", buffer, &ip, port);

This leads to the fact that buffer[] was left uninitialized and
contained some stack value. When we call nf_nat_mangle_tcp_packet(),
we call strlen(buffer) on excatly this uninitialized buffer. If we
are unlucky and the skb has enough tailroom, we overwrite resp. leak
contents with values that sit on our stack into the packet and send
that out to the receiver.

Since the rather informal DCC spec [1] does not seem to specify
IPv6 support right now, we log such occurences so that admins can
act accordingly, and drop the packet. I've looked into XChat source,
and IPv6 is not supported there: addresses are in u32 and print
via %u format string.

Therefore, restore old behaviour as in IPv4, use snprintf(). The
IRC helper does not support IPv6 by now. By this, we can safely use
strlen(buffer) in nf_nat_mangle_tcp_packet() and prevent a buffer
overflow. Also simplify some code as we now have ct variable anyway.

  [1] http://www.irchelp.org/irchelp/rfc/ctcpspec.html

Fixes: 5901b6be885e ("netfilter: nf_nat: support IPv6 in IRC NAT helper")
Signed-off-by: Daniel Borkmann 
Cc: Harald Welte 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: fix wrong byte order in nf_ct_seqadj_set internal information

2014-01-15T23:31:43+00:00

commit 23dfe136e2bf8d9ea1095704c535368a9bc721da upstream.

In commit 41d73ec053d2, sequence number adjustments were moved to a
separate file. Unfortunately, the sequence numbers that are stored
in the nf_ct_seqadj structure are expressed in host byte order. The
necessary ntohl call was removed when the call to adjust_tcp_sequence
was collapsed into nf_ct_seqadj_set. This broke the FTP NAT helper.
Fix it by adding back the byte order conversions.

Reported-by: Dawid Stawiarski 
Signed-off-by: Phil Oester 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: push reasm skb through instead of original frag skbs

2013-12-08T15:29:13+00:00

[ Upstream commit 6aafeef03b9d9ecf255f3a80ed85ee070260e1ae ]

Pushing original fragments through causes several problems. For example
for matching, frags may not be matched correctly. Take following
example:


On HOSTA do:
ip6tables -I INPUT -p icmpv6 -j DROP
ip6tables -I INPUT -p icmpv6 -m icmp6 --icmpv6-type 128 -j ACCEPT

and on HOSTB you do:
ping6 HOSTA -s2000    (MTU is 1500)

Incoming echo requests will be filtered out on HOSTA. This issue does
not occur with smaller packets than MTU (where fragmentation does not happen)


As was discussed previously, the only correct solution seems to be to use
reassembled skb instead of separete frags. Doing this has positive side
effects in reducing sk_buff by one pointer (nfct_reasm) and also the reams
dances in ipvs and conntrack can be removed.

Future plan is to remove net/ipv6/netfilter/nf_conntrack_reasm.c
entirely and use code in net/ipv6/reassembly.c instead.

Signed-off-by: Jiri Pirko 
Acked-by: Julian Anastasov 
Signed-off-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman