linux-stable.git/include/net/netns, branch linux-4.9.y Linux kernel stable tree inet: switch IP ID generator to siphash 2019-08-25T08:51:42+00:00 Eric Dumazet edumazet@google.com 2019-08-16T23:01:27+00:00 b97a2f3d58f439d11ececb2faa21dac775d63c5c commit df453700e8d81b1bdafdf684365ee2b9431fb702 upstream. According to Amit Klein and Benny Pinkas, IP ID generation is too weak and might be used by attackers. Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix()) having 64bit key and Jenkins hash is risky. It is time to switch to siphash and its 128bit keys. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit df453700e8d81b1bdafdf684365ee2b9431fb702 upstream.

According to Amit Klein and Benny Pinkas, IP ID generation is too weak
and might be used by attackers.

Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix())
having 64bit key and Jenkins hash is risky.

It is time to switch to siphash and its 128bit keys.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp: add tcp_min_snd_mss sysctl 2019-06-17T17:53:33+00:00 Eric Dumazet edumazet@google.com 2019-06-16T00:44:24+00:00 8e39cbc03dafa3731d22533f869bf326c0e6e6f8 commit 5f3e2bf008c2221478101ee72f5cb4654b9fc363 upstream. Some TCP peers announce a very small MSS option in their SYN and/or SYN/ACK messages. This forces the stack to send packets with a very high network/cpu overhead. Linux has enforced a minimal value of 48. Since this value includes the size of TCP options, and that the options can consume up to 40 bytes, this means that each segment can include only 8 bytes of payload. In some cases, it can be useful to increase the minimal value to a saner value. We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility reasons. Note that TCP_MAXSEG socket option enforces a minimal value of (TCP_MIN_MSS). David Miller increased this minimal value in commit c39508d6f118 ("tcp: Make TCP_MAXSEG minimum more correct.") from 64 to 88. We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS. CVE-2019-11479 -- tcp mss hardcoded to 48 Signed-off-by: Eric Dumazet <edumazet@google.com> Suggested-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5f3e2bf008c2221478101ee72f5cb4654b9fc363 upstream.

Some TCP peers announce a very small MSS option in their SYN and/or
SYN/ACK messages.

This forces the stack to send packets with a very high network/cpu
overhead.

Linux has enforced a minimal value of 48. Since this value includes
the size of TCP options, and that the options can consume up to 40
bytes, this means that each segment can include only 8 bytes of payload.

In some cases, it can be useful to increase the minimal value
to a saner value.

We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility
reasons.

Note that TCP_MAXSEG socket option enforces a minimal value
of (TCP_MIN_MSS). David Miller increased this minimal value
in commit c39508d6f118 ("tcp: Make TCP_MAXSEG minimum more correct.")
from 64 to 88.

We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS.

CVE-2019-11479 -- tcp mss hardcoded to 48

Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Jonathan Looney <jtl@netflix.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Bruce Curtis <brucec@netflix.com>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
netns: provide pure entropy for net_hash_mix() 2019-04-17T06:36:46+00:00 Eric Dumazet edumazet@google.com 2019-03-27T15:21:30+00:00 6996763856e1fb27ccae260e41fd73a3fff56678 [ Upstream commit 355b98553789b646ed97ad801a619ff898471b92 ] net_hash_mix() currently uses kernel address of a struct net, and is used in many places that could be used to reveal this address to a patient attacker, thus defeating KASLR, for the typical case (initial net namespace, &init_net is not dynamically allocated) I believe the original implementation tried to avoid spending too many cycles in this function, but security comes first. Also provide entropy regardless of CONFIG_NET_NS. Fixes: 0b4419162aa6 ("netns: introduce the net_hash_mix "salt" for hashes") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 355b98553789b646ed97ad801a619ff898471b92 ]

net_hash_mix() currently uses kernel address of a struct net,
and is used in many places that could be used to reveal this
address to a patient attacker, thus defeating KASLR, for
the typical case (initial net namespace, &init_net is
not dynamically allocated)

I believe the original implementation tried to avoid spending
too many cycles in this function, but security comes first.

Also provide entropy regardless of CONFIG_NET_NS.

Fixes: 0b4419162aa6 ("netns: introduce the net_hash_mix "salt" for hashes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
netfilter: ipv6: nf_defrag: reduce struct net memory waste 2018-08-24T11:12:26+00:00 Eric Dumazet edumazet@google.com 2018-06-13T17:11:56+00:00 a677cc36431f68c1208bfe288fa5f407c0114094 [ Upstream commit 9ce7bc036ae4cfe3393232c86e9e1fea2153c237 ] It is a waste of memory to use a full "struct netns_sysctl_ipv6" while only one pointer is really used, considering netns_sysctl_ipv6 keeps growing. Also, since "struct netns_frags" has cache line alignment, it is better to move the frags_hdr pointer outside, otherwise we spend a full cache line for this pointer. This saves 192 bytes of memory per netns. Fixes: c038a767cd69 ("ipv6: add a new namespace for nf_conntrack_reasm") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 9ce7bc036ae4cfe3393232c86e9e1fea2153c237 ]

It is a waste of memory to use a full "struct netns_sysctl_ipv6"
while only one pointer is really used, considering netns_sysctl_ipv6
keeps growing.

Also, since "struct netns_frags" has cache line alignment,
it is better to move the frags_hdr pointer outside, otherwise
we spend a full cache line for this pointer.

This saves 192 bytes of memory per netns.

Fixes: c038a767cd69 ("ipv6: add a new namespace for nf_conntrack_reasm")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-09-25T21:34:19+00:00 Pablo Neira Ayuso pablo@netfilter.org 2016-09-25T21:23:57+00:00 f20fbc0717f9f007c94b2641134b19228d0ce9ed Conflicts: net/netfilter/core.c net/netfilter/nf_tables_netdev.c Resolve two conflicts before pull request for David's net-next tree: 1) Between c73c24849011 ("netfilter: nf_tables_netdev: remove redundant ip_hdr assignment") from the net tree and commit ddc8b6027ad0 ("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()"). 2) Between e8bffe0cf964 ("net: Add _nf_(un)register_hooks symbols") and Aaron Conole's patches to replace list_head with single linked list. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
Conflicts:
	net/netfilter/core.c
	net/netfilter/nf_tables_netdev.c

Resolve two conflicts before pull request for David's net-next tree:

1) Between c73c24849011 ("netfilter: nf_tables_netdev: remove redundant
   ip_hdr assignment") from the net tree and commit ddc8b6027ad0
   ("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()").

2) Between e8bffe0cf964 ("net: Add _nf_(un)register_hooks symbols") and
   Aaron Conole's patches to replace list_head with single linked list.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: replace list_head with single linked list 2016-09-25T12:38:48+00:00 Aaron Conole aconole@bytheb.org 2016-09-21T15:35:07+00:00 e3b37f11e6e4e6b6f02cc762f182ce233d2c1c9d The netfilter hook list never uses the prev pointer, and so can be trimmed to be a simple singly-linked list. In addition to having a more light weight structure for hook traversal, struct net becomes 5568 bytes (down from 6400) and struct net_device becomes 2176 bytes (down from 2240). Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
The netfilter hook list never uses the prev pointer, and so can be trimmed to
be a simple singly-linked list.

In addition to having a more light weight structure for hook traversal,
struct net becomes 5568 bytes (down from 6400) and struct net_device becomes
2176 bytes (down from 2240).

Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2016-09-08T20:09:41+00:00 David S. Miller davem@davemloft.net 2016-09-08T20:09:41+00:00 575f9c43e709ab5008047eb5c68b99fe04592400 Steffen Klassert says: ==================== ipsec-next 2016-09-08 1) Constify the xfrm_replay structures. From Julia Lawall 2) Protect xfrm state hash tables with rcu, lookups can be done now without acquiring xfrm_state_lock. From Florian Westphal. 3) Protect xfrm policy hash tables with rcu, lookups can be done now without acquiring xfrm_policy_lock. From Florian Westphal. 4) We don't need to have a garbage collector list per namespace anymore, so use a global one instead. From Florian Westphal. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> 
Steffen Klassert says:

====================
ipsec-next 2016-09-08

1) Constify the xfrm_replay structures. From Julia Lawall

2) Protect xfrm state hash tables with rcu, lookups
   can be done now without acquiring xfrm_state_lock.
   From Florian Westphal.

3) Protect xfrm policy hash tables with rcu, lookups
   can be done now without acquiring xfrm_policy_lock.
   From Florian Westphal.

4) We don't need to have a garbage collector list per
   namespace anymore, so use a global one instead.
   From Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
xfrm: state: remove per-netns gc task 2016-08-24T11:16:06+00:00 Florian Westphal fw@strlen.de 2016-08-23T14:00:12+00:00 35db57bbc4b7ab810bba6e6d6954a0faf5a842cf After commit 5b8ef3415a21f173 ("xfrm: Remove ancient sleeping when the SA is in acquire state") gc does not need any per-netns data anymore. As far as gc is concerned all state structs are the same, so we can use a global work struct for it. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> 
After commit 5b8ef3415a21f173
("xfrm: Remove ancient sleeping when the SA is in acquire state")
gc does not need any per-netns data anymore.

As far as gc is concerned all state structs are the same, so we
can use a global work struct for it.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
netfilter: remove ip_conntrack* sysctl compat code 2016-08-13T11:27:13+00:00 Pablo Neira Ayuso pablo@netfilter.org 2016-08-12T11:47:06+00:00 adf0516845bcd0e626323c858ece28ee58c74455 This backward compatibility has been around for more than ten years, since Yasuyuki Kozakai introduced IPv6 in conntrack. These days, we have alternate /proc/net/nf_conntrack* entries, the ctnetlink interface and the conntrack utility got adopted by many people in the user community according to what I observed on the netfilter user mailing list. So let's get rid of this. Note that nf_conntrack_htable_size and unsigned int nf_conntrack_max do not need to be exported as symbol anymore. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
This backward compatibility has been around for more than ten years,
since Yasuyuki Kozakai introduced IPv6 in conntrack. These days, we have
alternate /proc/net/nf_conntrack* entries, the ctnetlink interface and
the conntrack utility got adopted by many people in the user community
according to what I observed on the netfilter user mailing list.

So let's get rid of this.

Note that nf_conntrack_htable_size and unsigned int nf_conntrack_max do
not need to be exported as symbol anymore.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
xfrm: policy: convert policy_lock to spinlock 2016-08-12T06:07:12+00:00 Florian Westphal fw@strlen.de 2016-08-11T13:17:59+00:00 9d0380df6217e8dd014118fa1c99dda9974f3613 After earlier patches conversions all spots acquire the writer lock and we can now convert this to a normal spinlock. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> 
After earlier patches conversions all spots acquire the writer lock and
we can now convert this to a normal spinlock.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>