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9986 commits

Author SHA1 Message Date
Lorenzo Colitti
e2d118a1cb net: inet: Support UID-based routing in IP protocols.
- Use the UID in routing lookups made by protocol connect() and
  sendmsg() functions.
- Make sure that routing lookups triggered by incoming packets
  (e.g., Path MTU discovery) take the UID of the socket into
  account.
- For packets not associated with a userspace socket, (e.g., ping
  replies) use UID 0 inside the user namespace corresponding to
  the network namespace the socket belongs to. This allows
  all namespaces to apply routing and iptables rules to
  kernel-originated traffic in that namespaces by matching UID 0.
  This is better than using the UID of the kernel socket that is
  sending the traffic, because the UID of kernel sockets created
  at namespace creation time (e.g., the per-processor ICMP and
  TCP sockets) is the UID of the user that created the socket,
  which might not be mapped in the namespace.

Tested: compiles allnoconfig, allyesconfig, allmodconfig
Tested: https://android-review.googlesource.com/253302
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-04 14:45:23 -04:00
Lorenzo Colitti
622ec2c9d5 net: core: add UID to flows, rules, and routes
- Define a new FIB rule attributes, FRA_UID_RANGE, to describe a
  range of UIDs.
- Define a RTA_UID attribute for per-UID route lookups and dumps.
- Support passing these attributes to and from userspace via
  rtnetlink. The value INVALID_UID indicates no UID was
  specified.
- Add a UID field to the flow structures.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-04 14:45:23 -04:00
Lorenzo Colitti
86741ec254 net: core: Add a UID field to struct sock.
Protocol sockets (struct sock) don't have UIDs, but most of the
time, they map 1:1 to userspace sockets (struct socket) which do.

Various operations such as the iptables xt_owner match need
access to the "UID of a socket", and do so by following the
backpointer to the struct socket. This involves taking
sk_callback_lock and doesn't work when there is no socket
because userspace has already called close().

Simplify this by adding a sk_uid field to struct sock whose value
matches the UID of the corresponding struct socket. The semantics
are as follows:

1. Whenever sk_socket is non-null: sk_uid is the same as the UID
   in sk_socket, i.e., matches the return value of sock_i_uid.
   Specifically, the UID is set when userspace calls socket(),
   fchown(), or accept().
2. When sk_socket is NULL, sk_uid is defined as follows:
   - For a socket that no longer has a sk_socket because
     userspace has called close(): the previous UID.
   - For a cloned socket (e.g., an incoming connection that is
     established but on which userspace has not yet called
     accept): the UID of the socket it was cloned from.
   - For a socket that has never had an sk_socket: UID 0 inside
     the user namespace corresponding to the network namespace
     the socket belongs to.

Kernel sockets created by sock_create_kern are a special case
of #1 and sk_uid is the user that created them. For kernel
sockets created at network namespace creation time, such as the
per-processor ICMP and TCP sockets, this is the user that created
the network namespace.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-04 14:45:22 -04:00
Willem de Bruijn
70ecc24841 ipv4: add IP_RECVFRAGSIZE cmsg
The IP stack records the largest fragment of a reassembled packet
in IPCB(skb)->frag_max_size. When reading a datagram or raw packet
that arrived fragmented, expose the value to allow applications to
estimate receive path MTU.

Tested:
  Sent data over a veth pair of which the source has a small mtu.
  Sent data using netcat, received using a dedicated process.

  Verified that the cmsg IP_RECVFRAGSIZE is returned only when
  data arrives fragmented, and in that cases matches the veth mtu.

    ip link add veth0 type veth peer name veth1

    ip netns add from
    ip netns add to

    ip link set dev veth1 netns to
    ip netns exec to ip addr add dev veth1 192.168.10.1/24
    ip netns exec to ip link set dev veth1 up

    ip link set dev veth0 netns from
    ip netns exec from ip addr add dev veth0 192.168.10.2/24
    ip netns exec from ip link set dev veth0 up
    ip netns exec from ip link set dev veth0 mtu 1300
    ip netns exec from ethtool -K veth0 ufo off

    dd if=/dev/zero bs=1 count=1400 2>/dev/null > payload

    ip netns exec to ./recv_cmsg_recvfragsize -4 -u -p 6000 &
    ip netns exec from nc -q 1 -u 192.168.10.1 6000 < payload

  using github.com/wdebruij/kerneltools/blob/master/tests/recvfragsize.c

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-03 15:41:11 -04:00
David S. Miller
4cb551a100 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for your net-next
tree. This includes better integration with the routing subsystem for
nf_tables, explicit notrack support and smaller updates. More
specifically, they are:

1) Add fib lookup expression for nf_tables, from Florian Westphal. This
   new expression provides a native replacement for iptables addrtype
   and rp_filter matches. This is more flexible though, since we can
   populate the kernel flowi representation to inquire fib to
   accomodate new usecases, such as RTBH through skb mark.

2) Introduce rt expression for nf_tables, from Anders K. Pedersen. This
   new expression allow you to access skbuff route metadata, more
   specifically nexthop and classid fields.

3) Add notrack support for nf_tables, to skip conntracking, requested by
   many users already.

4) Add boilerplate code to allow to use nf_log infrastructure from
   nf_tables ingress.

5) Allow to mangle pkttype from nf_tables prerouting chain, to emulate
   the xtables cluster match, from Liping Zhang.

6) Move socket lookup code into generic nf_socket_* infrastructure so
   we can provide a native replacement for the xtables socket match.

7) Make sure nfnetlink_queue data that is updated on every packets is
   placed in a different cache from read-only data, from Florian Westphal.

8) Handle NF_STOLEN from nf_tables core, also from Florian Westphal.

9) Start round robin number generation in nft_numgen from zero,
   instead of n-1, for consistency with xtables statistics match,
   patch from Liping Zhang.

10) Set GFP_NOWARN flag in skbuff netlink allocations in nfnetlink_log,
    given we retry with a smaller allocation on failure, from Calvin Owens.

11) Cleanup xt_multiport to use switch(), from Gao feng.

12) Remove superfluous check in nft_immediate and nft_cmp, from
    Liping Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-02 14:57:47 -04:00
Pablo Neira Ayuso
8db4c5be88 netfilter: move socket lookup infrastructure to nf_socket_ipv{4,6}.c
We need this split to reuse existing codebase for the upcoming nf_tables
socket expression.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-01 20:50:31 +01:00
Pablo Neira Ayuso
1fddf4bad0 netfilter: nf_log: add packet logging for netdev family
Move layer 2 packet logging into nf_log_l2packet() that resides in
nf_log_common.c, so this can be shared by both bridge and netdev
families.

This patch adds the boiler plate code to register the netdev logging
family.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-01 20:50:30 +01:00
Florian Westphal
f6d0cbcf09 netfilter: nf_tables: add fib expression
Add FIB expression, supported for ipv4, ipv6 and inet family (the latter
just dispatches to ipv4 or ipv6 one based on nfproto).

Currently supports fetching output interface index/name and the
rtm_type associated with an address.

This can be used for adding path filtering. rtm_type is useful
to e.g. enforce a strong-end host model where packets
are only accepted if daddr is configured on the interface the
packet arrived on.

The fib expression is a native nftables alternative to the
xtables addrtype and rp_filter matches.

FIB result order for oif/oifname retrieval is as follows:
 - if packet is local (skb has rtable, RTF_LOCAL set, this
   will also catch looped-back multicast packets), set oif to
   the loopback interface.
 - if fib lookup returns an error, or result points to local,
   store zero result.  This means '--local' option of -m rpfilter
   is not supported. It is possible to use 'fib type local' or add
   explicit saddr/daddr matching rules to create exceptions if this
   is really needed.
 - store result in the destination register.
   In case of multiple routes, search set for desired oif in case
   strict matching is requested.

ipv4 and ipv6 behave fib expressions are supposed to behave the same.

[ I have collapsed Arnd Bergmann's ("netfilter: nf_tables: fib warnings")

	http://patchwork.ozlabs.org/patch/688615/

  to address fallout from this patch after rebasing nf-next, that was
  posted to address compilation warnings. --pablo ]

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-01 20:50:14 +01:00
Eric Dumazet
bd68a2a854 net: set SK_MEM_QUANTUM to 4096
Systems with large pages (64KB pages for example) do not always have
huge quantity of memory.

A big SK_MEM_QUANTUM value leads to fewer interactions with the
global counters (like tcp_memory_allocated) but might trigger
memory pressure much faster, giving suboptimal TCP performance
since windows are lowered to ridiculous values.

Note that sysctl_mem units being in pages and in ABI, we also need
to change sk_prot_mem_limits() accordingly.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-31 20:59:58 -04:00
David S. Miller
27058af401 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Mostly simple overlapping changes.

For example, David Ahern's adjacency list revamp in 'net-next'
conflicted with an adjacency list traversal bug fix in 'net'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-30 12:42:58 -04:00
Linus Torvalds
2a26d99b25 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "Lots of fixes, mostly drivers as is usually the case.

   1) Don't treat zero DMA address as invalid in vmxnet3, from Alexey
      Khoroshilov.

   2) Fix element timeouts in netfilter's nft_dynset, from Anders K.
      Pedersen.

   3) Don't put aead_req crypto struct on the stack in mac80211, from
      Ard Biesheuvel.

   4) Several uninitialized variable warning fixes from Arnd Bergmann.

   5) Fix memory leak in cxgb4, from Colin Ian King.

   6) Fix bpf handling of VLAN header push/pop, from Daniel Borkmann.

   7) Several VRF semantic fixes from David Ahern.

   8) Set skb->protocol properly in ip6_tnl_xmit(), from Eli Cooper.

   9) Socket needs to be locked in udp_disconnect(), from Eric Dumazet.

  10) Div-by-zero on 32-bit fix in mlx4 driver, from Eugenia Emantayev.

  11) Fix stale link state during failover in NCSCI driver, from Gavin
      Shan.

  12) Fix netdev lower adjacency list traversal, from Ido Schimmel.

  13) Propvide proper handle when emitting notifications of filter
      deletes, from Jamal Hadi Salim.

  14) Memory leaks and big-endian issues in rtl8xxxu, from Jes Sorensen.

  15) Fix DESYNC_FACTOR handling in ipv6, from Jiri Bohac.

  16) Several routing offload fixes in mlxsw driver, from Jiri Pirko.

  17) Fix broadcast sync problem in TIPC, from Jon Paul Maloy.

  18) Validate chunk len before using it in SCTP, from Marcelo Ricardo
      Leitner.

  19) Revert a netns locking change that causes regressions, from Paul
      Moore.

  20) Add recursion limit to GRO handling, from Sabrina Dubroca.

  21) GFP_KERNEL in irq context fix in ibmvnic, from Thomas Falcon.

  22) Avoid accessing stale vxlan/geneve socket in data path, from
      Pravin Shelar"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (189 commits)
  geneve: avoid using stale geneve socket.
  vxlan: avoid using stale vxlan socket.
  qede: Fix out-of-bound fastpath memory access
  net: phy: dp83848: add dp83822 PHY support
  enic: fix rq disable
  tipc: fix broadcast link synchronization problem
  ibmvnic: Fix missing brackets in init_sub_crq_irqs
  ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context
  Revert "ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context"
  arch/powerpc: Update parameters for csum_tcpudp_magic & csum_tcpudp_nofold
  net/mlx4_en: Save slave ethtool stats command
  net/mlx4_en: Fix potential deadlock in port statistics flow
  net/mlx4: Fix firmware command timeout during interrupt test
  net/mlx4_core: Do not access comm channel if it has not yet been initialized
  net/mlx4_en: Fix panic during reboot
  net/mlx4_en: Process all completions in RX rings after port goes up
  net/mlx4_en: Resolve dividing by zero in 32-bit system
  net/mlx4_core: Change the default value of enable_qos
  net/mlx4_core: Avoid setting ports to auto when only one port type is supported
  net/mlx4_core: Fix the resource-type enum in res tracker to conform to FW spec
  ...
2016-10-29 20:33:20 -07:00
pravin shelar
c6fcc4fc5f vxlan: avoid using stale vxlan socket.
When vxlan device is closed vxlan socket is freed. This
operation can race with vxlan-xmit function which
dereferences vxlan socket. Following patch uses RCU
mechanism to avoid this situation.

Signed-off-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 20:56:31 -04:00
David S. Miller
32ab0a38f0 Among various cleanups and improvements, we have the following:
* client FILS authentication support in mac80211 (Jouni)
  * AP/VLAN multicast improvements (Michael Braun)
  * config/advertising support for differing beacon intervals on
    multiple virtual interfaces (Purushottam Kushwaha, myself)
  * deprecate the old WDS mode for cfg80211-based drivers, the
    mode is hardly usable since it doesn't support any "modern"
    features like WPA encryption (2003), HT (2009) or VHT (2014),
    I'm not even sure WEP (introduced in 1997) could be done.
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Merge tag 'mac80211-next-for-davem-2016-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
Among various cleanups and improvements, we have the following:
 * client FILS authentication support in mac80211 (Jouni)
 * AP/VLAN multicast improvements (Michael Braun)
 * config/advertising support for differing beacon intervals on
   multiple virtual interfaces (Purushottam Kushwaha, myself)
 * deprecate the old WDS mode for cfg80211-based drivers, the
   mode is hardly usable since it doesn't support any "modern"
   features like WPA encryption (2003), HT (2009) or VHT (2014),
   I'm not even sure WEP (introduced in 1997) could be done.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 17:28:45 -04:00
David S. Miller
880b583ce1 Just two fixes:
* a fix to process all events while suspending, so any
    potential calls into the driver are done before it is
    suspended
  * small markup fixes for the sphinx documentation conversion
    that's coming into the tree via the doc tree
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Merge tag 'mac80211-for-davem-2016-10-27' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
Just two fixes:
 * a fix to process all events while suspending, so any
   potential calls into the driver are done before it is
   suspended
 * small markup fixes for the sphinx documentation conversion
   that's coming into the tree via the doc tree
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 15:54:16 -04:00
Eric Dumazet
5ea8ea2cb7 tcp/dccp: drop SYN packets if accept queue is full
Per listen(fd, backlog) rules, there is really no point accepting a SYN,
sending a SYNACK, and dropping the following ACK packet if accept queue
is full, because application is not draining accept queue fast enough.

This behavior is fooling TCP clients that believe they established a
flow, while there is nothing at server side. They might then send about
10 MSS (if using IW10) that will be dropped anyway while server is under
stress.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 15:09:21 -04:00
Thomas Graf
b15ca182ed netlink: Add nla_memdup() to wrap kmemdup() use on nlattr
Wrap several common instances of:
	kmemdup(nla_data(attr), nla_len(attr), GFP_KERNEL);

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 14:57:42 -04:00
David Ahern
d5d32e4b76 net: ipv6: Do not consider link state for nexthop validation
Similar to IPv4, do not consider link state when validating next hops.

Currently, if the link is down default routes can fail to insert:
 $ ip -6 ro add vrf blue default via 2100:2::64 dev eth2
 RTNETLINK answers: No route to host

With this patch the command succeeds.

Fixes: 8c14586fc3 ("net: ipv6: Use passed in table for nexthop lookups")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:33:12 -04:00
David Ahern
830218c1ad net: ipv6: Fix processing of RAs in presence of VRF
rt6_add_route_info and rt6_add_dflt_router were updated to pull the FIB
table from the device index, but the corresponding rt6_get_route_info
and rt6_get_dflt_router functions were not leading to the failure to
process RA's:

    ICMPv6: RA: ndisc_router_discovery failed to add default route

Fix the 'get' functions by using the table id associated with the
device when applicable.

Also, now that default routes can be added to tables other than the
default table, rt6_purge_dflt_routers needs to be updated as well to
look at all tables. To handle that efficiently, add a flag to the table
denoting if it is has a default route via RA.

Fixes: ca254490c8 ("net: Add VRF support to IPv6 stack")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:30:52 -04:00
Johannes Berg
2ae0f17df1 genetlink: use idr to track families
Since generic netlink family IDs are small integers, allocated
densely, IDR is an ideal match for lookups. Replace the existing
hand-written hash-table with IDR for allocation and lookup.

This lets the families only be written to once, during register,
since the list_head can be removed and removal of a family won't
cause any writes.

It also slightly reduces the code size (by about 1.3k on x86-64).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:16:09 -04:00
Johannes Berg
489111e5c2 genetlink: statically initialize families
Instead of providing macros/inline functions to initialize
the families, make all users initialize them statically and
get rid of the macros.

This reduces the kernel code size by about 1.6k on x86-64
(with allyesconfig).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:16:09 -04:00
Johannes Berg
a07ea4d994 genetlink: no longer support using static family IDs
Static family IDs have never really been used, the only
use case was the workaround I introduced for those users
that assumed their family ID was also their multicast
group ID.

Additionally, because static family IDs would never be
reserved by the generic netlink code, using a relatively
low ID would only work for built-in families that can be
registered immediately after generic netlink is started,
which is basically only the control family (apart from
the workaround code, which I also had to add code for so
it would reserve those IDs)

Thus, anything other than GENL_ID_GENERATE is flawed and
luckily not used except in the cases I mentioned. Move
those workarounds into a few lines of code, and then get
rid of GENL_ID_GENERATE entirely, making it more robust.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:16:09 -04:00
Johannes Berg
c90c39dab3 genetlink: introduce and use genl_family_attrbuf()
This helper function allows family implementations to access
their family's attrbuf. This gets rid of the attrbuf usage
in families, and also adds locking validation, since it's not
valid to use the attrbuf with parallel_ops or outside of the
dumpit callback.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:16:08 -04:00
Antonio Quartulli
4fe77d82ef skbedit: allow the user to specify bitmask for mark
The user may want to use only some bits of the skb mark in
his skbedit rules because the remaining part might be used by
something else.

Introduce the "mask" parameter to the skbedit actor in order
to implement such functionality.

When the mask is specified, only those bits selected by the
latter are altered really changed by the actor, while the
rest is left untouched.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:07:25 -04:00
vamsi krishna
088e8df82f cfg80211: Add support to update connection parameters
Add functionality to update the connection parameters when in connected
state, so that driver/firmware uses the updated parameters for
subsequent roaming. This is for drivers that support internal BSS
selection and roaming. The new command does not change the current
association state, i.e., it can be used to update IE contents for future
(re)associations without causing an immediate disassociation or
reassociation with the current BSS.

This commit implements the required functionality for updating IEs for
(Re)Association Request frame only. Other parameters can be added in
future when required.

Signed-off-by: vamsi krishna <vamsin@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27 16:03:28 +02:00
Michael Braun
ce0ce13a1c cfg80211: configure multicast to unicast for AP interfaces
Add the ability to configure if an AP (and associated VLANs) will
do multicast-to-unicast conversion for ARP, IPv4 and IPv6 frames
(possibly within 802.1Q). If enabled, such frames are to be sent
to each station separately, with the DA replaced by their own MAC
address rather than the group address.

Note that this may break certain expectations of the receiver,
such as the ability to drop unicast IP packets received within
multicast L2 frames, or the ability to not send ICMP destination
unreachable messages for packets received in L2 multicast (which
is required, but the receiver can't tell the difference if this
new option is enabled.)

This also doesn't implement the 802.11 DMS (directed multicast
service).

Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
[fix disabling, add better documentation & commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27 16:03:27 +02:00
Jouni Malinen
348bd45669 cfg80211: Add KEK/nonces for FILS association frames
The new nl80211 attributes can be used to provide KEK and nonces to
allow the driver to encrypt and decrypt FILS (Re)Association
Request/Response frames in station mode.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27 16:03:24 +02:00
Jouni Malinen
3f817fe718 cfg80211: Define IEEE P802.11ai (FILS) information elements
Define the Element IDs and Element ID Extensions from IEEE
P802.11ai/D11.0. In addition, add a new cfg80211_find_ext_ie() wrapper
to make it easier to find information elements that used the Element ID
Extension field.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27 16:03:23 +02:00
Jouni Malinen
11b6b5a4ce cfg80211: Rename SAE_DATA to more generic AUTH_DATA
This adds defines and nl80211 extensions to allow FILS Authentication to
be implemented similarly to SAE. FILS does not need the special rules
for the Authentication transaction number and Status code fields, but it
does need to add non-IE fields. The previously used
NL80211_ATTR_SAE_DATA can be reused for this to avoid having to
duplicate that implementation. Rename that attribute to more generic
NL80211_ATTR_AUTH_DATA (with backwards compatibility define for
NL80211_SAE_DATA).

Also document the special rules related to the Authentication
transaction number and Status code fiels.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27 16:03:20 +02:00
Johannes Berg
4c8dea638c cfg80211: validate beacon int as part of iface combinations
Remove the pointless checking against interface combinations in
the initial basic beacon interval validation, that currently isn't
taking into account radar detection or channels properly. Instead,
just validate the basic range there, and then delay real checking
to the interface combination validation that drivers must do.

This means that drivers wanting to use the beacon_int_min_gcd will
now have to pass the new_beacon_int when validating the AP/mesh
start.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27 09:18:07 +02:00
Arend Van Spriel
73c7da3dae cfg80211: add generic helper to check interface is running
Add a helper using wdev to check if interface is running. This
deals with both non-netdev and netdev interfaces. In struct
wireless_dev replace 'p2p_started' and 'nan_started' by
'is_running' as those are mutually exclusive anyway, and unify
all the code to use wdev_running().

Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-27 09:08:44 +02:00
Eric Dumazet
10df8e6152 udp: fix IP_CHECKSUM handling
First bug was added in commit ad6f939ab1 ("ip: Add offset parameter to
ip_cmsg_recv") : Tom missed that ipv4 udp messages could be received on
AF_INET6 socket. ip_cmsg_recv(msg, skb) should have been replaced by
ip_cmsg_recv_offset(msg, skb, sizeof(struct udphdr));

Then commit e6afc8ace6 ("udp: remove headers from UDP packets before
queueing") forgot to adjust the offsets now UDP headers are pulled
before skb are put in receive queue.

Fixes: ad6f939ab1 ("ip: Add offset parameter to ip_cmsg_recv")
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Sam Kumar <samanthakumar@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-26 17:33:22 -04:00
Stephen Hemminger
293de7dee4 doc: update docbook annotations for socket and skb
The skbuff and sock structure both had missing parameter annotation
values.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-26 17:31:23 -04:00
Jani Nikula
b4f7f4ad42 mac80211: fix some sphinx warnings
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-26 08:01:07 +02:00
Cyrill Gorcunov
432490f9d4 net: ip, diag -- Add diag interface for raw sockets
In criu we are actively using diag interface to collect sockets
present in the system when dumping applications. And while for
unix, tcp, udp[lite], packet, netlink it works as expected,
the raw sockets do not have. Thus add it.

v2:
 - add missing sock_put calls in raw_diag_dump_one (by eric.dumazet@)
 - implement @destroy for diag requests (by dsa@)

v3:
 - add export of raw_abort for IPv6 (by dsa@)
 - pass net-admin flag into inet_sk_diag_fill due to
   changes in net-next branch (by dsa@)

v4:
 - use @pad in struct inet_diag_req_v2 for raw socket
   protocol specification: raw module carries sockets
   which may have custom protocol passed from socket()
   syscall and sole @sdiag_protocol is not enough to
   match underlied ones
 - start reporting protocol specifed in socket() call
   when sockets are raw ones for the same reason: user
   space tools like ss may parse this attribute and use
   it for socket matching

v5 (by eric.dumazet@):
 - use sock_hold in raw_sock_get instead of atomic_inc,
   we're holding (raw_v4_hashinfo|raw_v6_hashinfo)->lock
   when looking up so counter won't be zero here.

v6:
 - use sdiag_raw_protocol() helper which will access @pad
   structure used for raw sockets protocol specification:
   we can't simply rename this member without breaking uapi

v7:
 - sine sdiag_raw_protocol() helper is not suitable for
   uapi lets rather make an alias structure with proper
   names. __check_inet_diag_req_raw helper will catch
   if any of structure unintentionally changed.

CC: David S. Miller <davem@davemloft.net>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: David Ahern <dsa@cumulusnetworks.com>
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>
CC: Andrey Vagin <avagin@openvz.org>
CC: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-23 19:35:24 -04:00
Thomas Graf
f76a9db351 lwt: Remove unused len field
The field is initialized by ILA and MPLS but never used. Remove it.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-23 17:45:01 -04:00
Paolo Abeni
f970bd9e3a udp: implement memory accounting helpers
Avoid using the generic helpers.
Use the receive queue spin lock to protect the memory
accounting operation, both on enqueue and on dequeue.

On dequeue perform partial memory reclaiming, trying to
leave a quantum of forward allocated memory.

On enqueue use a custom helper, to allow some optimizations:
- use a plain spin_lock() variant instead of the slightly
  costly spin_lock_irqsave(),
- avoid dst_force check, since the calling code has already
  dropped the skb dst
- avoid orphaning the skb, since skb_steal_sock() already did
  the work for us

The above needs custom memory reclaiming on shutdown, provided
by the udp_destruct_sock().

v5 -> v6:
  - don't orphan the skb on enqueue

v4 -> v5:
  - replace the mem_lock with the receive queue spin lock
  - ensure that the bh is always allowed to enqueue at least
    a skb, even if sk_rcvbuf is exceeded

v3 -> v4:
  - reworked memory accunting, simplifying the schema
  - provide an helper for both memory scheduling and enqueuing

v1 -> v2:
  - use a udp specific destrctor to perform memory reclaiming
  - remove a couple of helpers, unneeded after the above cleanup
  - do not reclaim memory on dequeue if not under memory
    pressure
  - reworked the fwd accounting schema to avoid potential
    integer overflow

Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-22 17:05:05 -04:00
Paolo Abeni
f8c3bf00d4 net/socket: factor out helpers for memory and queue manipulation
Basic sock operations that udp code can use with its own
memory accounting schema. No functional change is introduced
in the existing APIs.

v4 -> v5:
  - avoid whitespace changes

v2 -> v4:
  - avoid exporting __sock_enqueue_skb

v1 -> v2:
  - avoid export sock_rmem_free

Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-22 17:05:05 -04:00
WANG Cong
8651be8f14 ipv6: fix a potential deadlock in do_ipv6_setsockopt()
Baozeng reported this deadlock case:

       CPU0                    CPU1
       ----                    ----
  lock([  165.136033] sk_lock-AF_INET6);
                               lock([  165.136033] rtnl_mutex);
                               lock([  165.136033] sk_lock-AF_INET6);
  lock([  165.136033] rtnl_mutex);

Similar to commit 87e9f03159
("ipv4: fix a potential deadlock in mcast getsockopt() path")
this is due to we still have a case, ipv6_sock_mc_close(),
where we acquire sk_lock before rtnl_lock. Close this deadlock
with the similar solution, that is always acquire rtnl lock first.

Fixes: baf606d9c9 ("ipv4,ipv6: grab rtnl before locking the socket")
Reported-by: Baozeng Ding <sploving1@gmail.com>
Tested-by: Baozeng Ding <sploving1@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-21 11:29:02 -04:00
Eric Dumazet
286c72deab udp: must lock the socket in udp_disconnect()
Baozeng Ding reported KASAN traces showing uses after free in
udp_lib_get_port() and other related UDP functions.

A CONFIG_DEBUG_PAGEALLOC=y kernel would eventually crash.

I could write a reproducer with two threads doing :

static int sock_fd;
static void *thr1(void *arg)
{
	for (;;) {
		connect(sock_fd, (const struct sockaddr *)arg,
			sizeof(struct sockaddr_in));
	}
}

static void *thr2(void *arg)
{
	struct sockaddr_in unspec;

	for (;;) {
		memset(&unspec, 0, sizeof(unspec));
	        connect(sock_fd, (const struct sockaddr *)&unspec,
			sizeof(unspec));
        }
}

Problem is that udp_disconnect() could run without holding socket lock,
and this was causing list corruptions.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-20 14:45:52 -04:00
Ilan Peer
0711d63878 cfg80211: allow aborting in-progress connection atttempts
On a disconnect request from userspace, cfg80211 currently calls
called rdev_disconnect() only in case that 'current_bss' was set,
i.e. connection had been established.

Change this to allow the userspace call to succeed and call the
driver's disconnect() method also while the connection attempt is
in progress, to be able to abort attempts.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
[change commit subject/message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-19 12:15:38 +02:00
Emmanuel Grumbach
f438ceb81d mac80211: uapsd_queues is in QoS IE order
The uapsd_queue field is in QoS IE order and not in
IEEE80211_AC_*'s order.
This means that mac80211 would get confused between
BK and BE which is certainly not such a big deal but
needs to be fixed.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-19 12:13:54 +02:00
Sara Sharon
f3fe4e93dd mac80211: add a HW flag for supporting HW TX fragmentation
Currently mac80211 determines whether HW does fragmentation
by checking whether the set_frag_threshold callback is set
or not.
However, some drivers may want to set the HW fragmentation
capability depending on HW generation.
Allow this by checking a HW flag instead of checking the
callback.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
[added the flag to ath10k and wlcore]
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-19 12:12:44 +02:00
Emmanuel Grumbach
0aa419ec6e mac80211: allow the driver not to pass the tid to ieee80211_sta_uapsd_trigger
iwlwifi will check internally that the tid maps to an AC
that is trigger enabled, but can't know what tid exactly.
Allow the driver to pass a generic tid and make mac80211
assume that a trigger frame was received.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-19 12:12:19 +02:00
Johannes Berg
a1264c3d6c wireless: radiotap: fix timestamp sampling position values
The values don't match the radiotap spec, corrected that.

Reported-by: Oz Shalev <oz.shalev@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-19 12:11:36 +02:00
David S. Miller
5cbee55736 This is relatively small, mostly to get the SG/crypto
from stack removal fix that crashes things when VMAP
 stack is used in conjunction with software crypto.
 
 Aside from that, we have:
  * a fix for AP_VLAN usage with the nl80211 frame command
  * two fixes (and two preparation patches) for A-MSDU, one
    to discard group-addressed (multicast) and unexpected
    4-address A-MSDUs, the other to validate A-MSDU inner
    MAC addresses properly to prevent controlled port bypass
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Merge tag 'mac80211-for-davem-2016-10-18' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
This is relatively small, mostly to get the SG/crypto
from stack removal fix that crashes things when VMAP
stack is used in conjunction with software crypto.

Aside from that, we have:
 * a fix for AP_VLAN usage with the nl80211 frame command
 * two fixes (and two preparation patches) for A-MSDU, one
   to discard group-addressed (multicast) and unexpected
   4-address A-MSDUs, the other to validate A-MSDU inner
   MAC addresses properly to prevent controlled port bypass
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-18 10:26:15 -04:00
David Ahern
a04a480d43 net: Require exact match for TCP socket lookups if dif is l3mdev
Currently, socket lookups for l3mdev (vrf) use cases can match a socket
that is bound to a port but not a device (ie., a global socket). If the
sysctl tcp_l3mdev_accept is not set this leads to ack packets going out
based on the main table even though the packet came in from an L3 domain.
The end result is that the connection does not establish creating
confusion for users since the service is running and a socket shows in
ss output. Fix by requiring an exact dif to sk_bound_dev_if match if the
skb came through an interface enslaved to an l3mdev device and the
tcp_l3mdev_accept is not set.

skb's through an l3mdev interface are marked by setting a flag in
inet{6}_skb_parm. The IPv6 variant is already set; this patch adds the
flag for IPv4. Using an skb flag avoids a device lookup on the dif. The
flag is set in the VRF driver using the IP{6}CB macros. For IPv4, the
inet_skb_parm struct is moved in the cb per commit 971f10eca1, so the
match function in the TCP stack needs to use TCP_SKB_CB. For IPv6, the
move is done after the socket lookup, so IP6CB is used.

The flags field in inet_skb_parm struct needs to be increased to add
another flag. There is currently a 1-byte hole following the flags,
so it can be expanded to u16 without increasing the size of the struct.

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-17 10:17:05 -04:00
Michael Braun
a3e2f4b6ed mac80211: fix A-MSDU outer SA/DA
According to IEEE 802.11-2012 section 8.3.2 table 8-19, the outer SA/DA
of A-MSDU frames need to be changed depending on FromDS/ToDS values.

Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
[use ether_addr_copy and add alignment annotations]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-10-17 11:43:33 +02:00
Tom Herbert
1104d9ba44 lwtunnel: Add destroy state operation
Users of lwt tunnels may set up some secondary state in build_state
function. Add a corresponding destroy_state function to allow users to
clean up state. This destroy state function is called from lwstate_free.
Also, we now free lwstate using kfree_rcu so user can assume structure
is not freed before rcu.

Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-15 17:33:41 -04:00
Linus Torvalds
d4d24d2d0a A single commit converting the mac80211 DocBook template over to Sphinx.
Only 32 more to go...
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Merge tag 'docs-4.9-2' of git://git.lwn.net/linux

Pull one more documentation update from Jonathan Corbet:
 "A single commit converting the mac80211 DocBook template over to
  Sphinx.  Only 32 more to go..."

* tag 'docs-4.9-2' of git://git.lwn.net/linux:
  docs-rst: sphinxify 802.11 documentation
2016-10-14 14:11:22 -07:00
Jiri Bohac
76506a986d IPv6: fix DESYNC_FACTOR
The IPv6 temporary address generation uses a variable called DESYNC_FACTOR
to prevent hosts updating the addresses at the same time. Quoting RFC 4941:

   ... The value DESYNC_FACTOR is a random value (different for each
   client) that ensures that clients don't synchronize with each other and
   generate new addresses at exactly the same time ...

DESYNC_FACTOR is defined as:

   DESYNC_FACTOR -- A random value within the range 0 - MAX_DESYNC_FACTOR.
   It is computed once at system start (rather than each time it is used)
   and must never be greater than (TEMP_VALID_LIFETIME - REGEN_ADVANCE).

First, I believe the RFC has a typo in it and meant to say: "and must
never be greater than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE)"

The reason is that at various places in the RFC, DESYNC_FACTOR is used in
a calculation like (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR) or
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE - DESYNC_FACTOR). It needs to be
smaller than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE) for the result of
these calculations to be larger than zero. It's never used in a
calculation together with TEMP_VALID_LIFETIME.

I already submitted an errata to the rfc-editor:
https://www.rfc-editor.org/errata_search.php?rfc=4941

The Linux implementation of DESYNC_FACTOR is very wrong:
max_desync_factor is used in places DESYNC_FACTOR should be used.
max_desync_factor is initialized to the RFC-recommended value for
MAX_DESYNC_FACTOR (600) but the whole point is to get a _random_ value.

And nothing ensures that the value used is not greater than
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE), which leads to underflows.  The
effect can easily be observed when setting the temp_prefered_lft sysctl
e.g. to 60. The preferred lifetime of the temporary addresses will be
bogus.

TEMP_PREFERRED_LIFETIME and REGEN_ADVANCE are not constants and can be
influenced by these three sysctls: regen_max_retry, dad_transmits and
temp_prefered_lft. Thus, the upper bound for desync_factor needs to be
re-calculated each time a new address is generated and if desync_factor is
larger than the new upper bound, a new random value needs to be
re-generated.

And since we already have max_desync_factor configurable per interface, we
also need to calculate and store desync_factor per interface.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-14 10:59:15 -04:00