Commit Graph

1098 Commits

Author SHA1 Message Date
Daniel Borkmann ec0223ec48 net: sctp: fix sctp_sf_do_5_1D_ce to verify if we/peer is AUTH capable
RFC4895 introduced AUTH chunks for SCTP; during the SCTP
handshake RANDOM; CHUNKS; HMAC-ALGO are negotiated (CHUNKS
being optional though):

  ---------- INIT[RANDOM; CHUNKS; HMAC-ALGO] ---------->
  <------- INIT-ACK[RANDOM; CHUNKS; HMAC-ALGO] ---------
  -------------------- COOKIE-ECHO -------------------->
  <-------------------- COOKIE-ACK ---------------------

A special case is when an endpoint requires COOKIE-ECHO
chunks to be authenticated:

  ---------- INIT[RANDOM; CHUNKS; HMAC-ALGO] ---------->
  <------- INIT-ACK[RANDOM; CHUNKS; HMAC-ALGO] ---------
  ------------------ AUTH; COOKIE-ECHO ---------------->
  <-------------------- COOKIE-ACK ---------------------

RFC4895, section 6.3. Receiving Authenticated Chunks says:

  The receiver MUST use the HMAC algorithm indicated in
  the HMAC Identifier field. If this algorithm was not
  specified by the receiver in the HMAC-ALGO parameter in
  the INIT or INIT-ACK chunk during association setup, the
  AUTH chunk and all the chunks after it MUST be discarded
  and an ERROR chunk SHOULD be sent with the error cause
  defined in Section 4.1. [...] If no endpoint pair shared
  key has been configured for that Shared Key Identifier,
  all authenticated chunks MUST be silently discarded. [...]

  When an endpoint requires COOKIE-ECHO chunks to be
  authenticated, some special procedures have to be followed
  because the reception of a COOKIE-ECHO chunk might result
  in the creation of an SCTP association. If a packet arrives
  containing an AUTH chunk as a first chunk, a COOKIE-ECHO
  chunk as the second chunk, and possibly more chunks after
  them, and the receiver does not have an STCB for that
  packet, then authentication is based on the contents of
  the COOKIE-ECHO chunk. In this situation, the receiver MUST
  authenticate the chunks in the packet by using the RANDOM
  parameters, CHUNKS parameters and HMAC_ALGO parameters
  obtained from the COOKIE-ECHO chunk, and possibly a local
  shared secret as inputs to the authentication procedure
  specified in Section 6.3. If authentication fails, then
  the packet is discarded. If the authentication is successful,
  the COOKIE-ECHO and all the chunks after the COOKIE-ECHO
  MUST be processed. If the receiver has an STCB, it MUST
  process the AUTH chunk as described above using the STCB
  from the existing association to authenticate the
  COOKIE-ECHO chunk and all the chunks after it. [...]

Commit bbd0d59809 introduced the possibility to receive
and verification of AUTH chunk, including the edge case for
authenticated COOKIE-ECHO. On reception of COOKIE-ECHO,
the function sctp_sf_do_5_1D_ce() handles processing,
unpacks and creates a new association if it passed sanity
checks and also tests for authentication chunks being
present. After a new association has been processed, it
invokes sctp_process_init() on the new association and
walks through the parameter list it received from the INIT
chunk. It checks SCTP_PARAM_RANDOM, SCTP_PARAM_HMAC_ALGO
and SCTP_PARAM_CHUNKS, and copies them into asoc->peer
meta data (peer_random, peer_hmacs, peer_chunks) in case
sysctl -w net.sctp.auth_enable=1 is set. If in INIT's
SCTP_PARAM_SUPPORTED_EXT parameter SCTP_CID_AUTH is set,
peer_random != NULL and peer_hmacs != NULL the peer is to be
assumed asoc->peer.auth_capable=1, in any other case
asoc->peer.auth_capable=0.

Now, if in sctp_sf_do_5_1D_ce() chunk->auth_chunk is
available, we set up a fake auth chunk and pass that on to
sctp_sf_authenticate(), which at latest in
sctp_auth_calculate_hmac() reliably dereferences a NULL pointer
at position 0..0008 when setting up the crypto key in
crypto_hash_setkey() by using asoc->asoc_shared_key that is
NULL as condition key_id == asoc->active_key_id is true if
the AUTH chunk was injected correctly from remote. This
happens no matter what net.sctp.auth_enable sysctl says.

The fix is to check for net->sctp.auth_enable and for
asoc->peer.auth_capable before doing any operations like
sctp_sf_authenticate() as no key is activated in
sctp_auth_asoc_init_active_key() for each case.

Now as RFC4895 section 6.3 states that if the used HMAC-ALGO
passed from the INIT chunk was not used in the AUTH chunk, we
SHOULD send an error; however in this case it would be better
to just silently discard such a maliciously prepared handshake
as we didn't even receive a parameter at all. Also, as our
endpoint has no shared key configured, section 6.3 says that
MUST silently discard, which we are doing from now onwards.

Before calling sctp_sf_pdiscard(), we need not only to free
the association, but also the chunk->auth_chunk skb, as
commit bbd0d59809 created a skb clone in that case.

I have tested this locally by using netfilter's nfqueue and
re-injecting packets into the local stack after maliciously
modifying the INIT chunk (removing RANDOM; HMAC-ALGO param)
and the SCTP packet containing the COOKIE_ECHO (injecting
AUTH chunk before COOKIE_ECHO). Fixed with this patch applied.

Fixes: bbd0d59809 ("[SCTP]: Implement the receive and verification of AUTH chunk")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Vlad Yasevich <yasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-03 16:39:36 -05:00
Daniel Borkmann 4c47af4d5e net: sctp: rework multihoming retransmission path selection to rfc4960
Problem statement: 1) both paths (primary path1 and alternate
path2) are up after the association has been established i.e.,
HB packets are normally exchanged, 2) path2 gets inactive after
path_max_retrans * max_rto timed out (i.e. path2 is down completely),
3) now, if a transmission times out on the only surviving/active
path1 (any ~1sec network service impact could cause this like
a channel bonding failover), then the retransmitted packets are
sent over the inactive path2; this happens with partial failover
and without it.

Besides not being optimal in the above scenario, a small failure
or timeout in the only existing path has the potential to cause
long delays in the retransmission (depending on RTO_MAX) until
the still active path is reselected. Further, when the T3-timeout
occurs, we have active_patch == retrans_path, and even though the
timeout occurred on the initial transmission of data, not a
retransmit, we end up updating retransmit path.

RFC4960, section 6.4. "Multi-Homed SCTP Endpoints" states under
6.4.1. "Failover from an Inactive Destination Address" the
following:

  Some of the transport addresses of a multi-homed SCTP endpoint
  may become inactive due to either the occurrence of certain
  error conditions (see Section 8.2) or adjustments from the
  SCTP user.

  When there is outbound data to send and the primary path
  becomes inactive (e.g., due to failures), or where the SCTP
  user explicitly requests to send data to an inactive
  destination transport address, before reporting an error to
  its ULP, the SCTP endpoint should try to send the data to an
  alternate __active__ destination transport address if one
  exists.

  When retransmitting data that timed out, if the endpoint is
  multihomed, it should consider each source-destination address
  pair in its retransmission selection policy. When retransmitting
  timed-out data, the endpoint should attempt to pick the most
  divergent source-destination pair from the original
  source-destination pair to which the packet was transmitted.

  Note: Rules for picking the most divergent source-destination
  pair are an implementation decision and are not specified
  within this document.

So, we should first reconsider to take the current active
retransmission transport if we cannot find an alternative
active one. If all of that fails, we can still round robin
through unkown, partial failover, and inactive ones in the
hope to find something still suitable.

Commit 4141ddc02a ("sctp: retran_path update bug fix") broke
that behaviour by selecting the next inactive transport when
no other active transport was found besides the current assoc's
peer.retran_path. Before commit 4141ddc02a, we would have
traversed through the list until we reach our peer.retran_path
again, and in case that is still in state SCTP_ACTIVE, we would
take it and return. Only if that is not the case either, we
take the next inactive transport.

Besides all that, another issue is that transports in state
SCTP_UNKNOWN could be preferred over transports in state
SCTP_ACTIVE in case a SCTP_ACTIVE transport appears after
SCTP_UNKNOWN in the transport list yielding a weaker transport
state to be used in retransmission.

This patch mostly reverts 4141ddc02a, but also rewrites
this function to introduce more clarity and strictness into
the code. A strict priority of transport states is enforced
in this patch, hence selection is active > unkown > partial
failover > inactive.

Fixes: 4141ddc02a ("sctp: retran_path update bug fix")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Acked-by: Vlad Yasevich <yasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-22 00:26:05 -05:00
Matija Glavinic Pecotic 7cce3b7568 net: sctp: Potentially-Failed state should not be reached from unconfirmed state
In current implementation it is possible to reach PF state from unconfirmed.
We can interpret sctp-failover-02 in a way that PF state is meant to be reached
only from active state, in the end, this is when entering PF state makes sense.
Here are few quotes from sctp-failover-02, but regardless of these, same
understanding can be reached from whole section 5:

Section 5.1, quickfailover guide:
    "The PF state is an intermediate state between Active and Failed states."

    "Each time the T3-rtx timer expires on an active or idle
    destination, the error counter of that destination address will
    be incremented.  When the value in the error counter exceeds
    PFMR, the endpoint should mark the destination transport address as PF."

There are several concrete reasons for such interpretation. For start, rfc4960
does not take into concern quickfailover algorithm. Therefore, quickfailover
must comply to 4960. Point where this compliance can be argued is following
behavior:
When PF is entered, association overall error counter is incremented for each
missed HB. This is contradictory to rfc4960, as address, while in unconfirmed
state, is subjected to probing, and while it is probed, it should not increment
association overall error counter. This has as a consequence that we might end
up in situation in which we drop association due path failure on unconfirmed
address, in case we have wrong configuration in a way:
Association.Max.Retrans == Path.Max.Retrans.

Another reason is that entering PF from unconfirmed will cause a loss of address
confirmed event when address is once (if) confirmed. This is fine from failover
guide point of view, but it is not consistent with behavior preceding failover
implementation and recommendation from 4960:

5.4.  Path Verification
   Whenever a path is confirmed, an indication MAY be given to the upper
   layer.

Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nsn.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-20 13:24:56 -05:00
David S. Miller 1e8d6421cf Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/bonding/bond_3ad.h
	drivers/net/bonding/bond_main.c

Two minor conflicts in bonding, both of which were overlapping
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-19 01:24:22 -05:00
Daniel Borkmann ffd5939381 net: sctp: fix sctp_connectx abi for ia32 emulation/compat mode
SCTP's sctp_connectx() abi breaks for 64bit kernels compiled with 32bit
emulation (e.g. ia32 emulation or x86_x32). Due to internal usage of
'struct sctp_getaddrs_old' which includes a struct sockaddr pointer,
sizeof(param) check will always fail in kernel as the structure in
64bit kernel space is 4bytes larger than for user binaries compiled
in 32bit mode. Thus, applications making use of sctp_connectx() won't
be able to run under such circumstances.

Introduce a compat interface in the kernel to deal with such
situations by using a 'struct compat_sctp_getaddrs_old' structure
where user data is copied into it, and then sucessively transformed
into a 'struct sctp_getaddrs_old' structure with the help of
compat_ptr(). That fixes sctp_connectx() abi without any changes
needed in user space, and lets the SCTP test suite pass when compiled
in 32bit and run on 64bit kernels.

Fixes: f9c67811eb ("sctp: Fix regression introduced by new sctp_connectx api")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-18 16:06:48 -05:00
Matija Glavinic Pecotic ef2820a735 net: sctp: Fix a_rwnd/rwnd management to reflect real state of the receiver's buffer
Implementation of (a)rwnd calculation might lead to severe performance issues
and associations completely stalling. These problems are described and solution
is proposed which improves lksctp's robustness in congestion state.

1) Sudden drop of a_rwnd and incomplete window recovery afterwards

Data accounted in sctp_assoc_rwnd_decrease takes only payload size (sctp data),
but size of sk_buff, which is blamed against receiver buffer, is not accounted
in rwnd. Theoretically, this should not be the problem as actual size of buffer
is double the amount requested on the socket (SO_RECVBUF). Problem here is
that this will have bad scaling for data which is less then sizeof sk_buff.
E.g. in 4G (LTE) networks, link interfacing radio side will have a large portion
of traffic of this size (less then 100B).

An example of sudden drop and incomplete window recovery is given below. Node B
exhibits problematic behavior. Node A initiates association and B is configured
to advertise rwnd of 10000. A sends messages of size 43B (size of typical sctp
message in 4G (LTE) network). On B data is left in buffer by not reading socket
in userspace.

Lets examine when we will hit pressure state and declare rwnd to be 0 for
scenario with above stated parameters (rwnd == 10000, chunk size == 43, each
chunk is sent in separate sctp packet)

Logic is implemented in sctp_assoc_rwnd_decrease:

socket_buffer (see below) is maximum size which can be held in socket buffer
(sk_rcvbuf). current_alloced is amount of data currently allocated (rx_count)

A simple expression is given for which it will be examined after how many
packets for above stated parameters we enter pressure state:

We start by condition which has to be met in order to enter pressure state:

	socket_buffer < currently_alloced;

currently_alloced is represented as size of sctp packets received so far and not
yet delivered to userspace. x is the number of chunks/packets (since there is no
bundling, and each chunk is delivered in separate packet, we can observe each
chunk also as sctp packet, and what is important here, having its own sk_buff):

	socket_buffer < x*each_sctp_packet;

each_sctp_packet is sctp chunk size + sizeof(struct sk_buff). socket_buffer is
twice the amount of initially requested size of socket buffer, which is in case
of sctp, twice the a_rwnd requested:

	2*rwnd < x*(payload+sizeof(struc sk_buff));

sizeof(struct sk_buff) is 190 (3.13.0-rc4+). Above is stated that rwnd is 10000
and each payload size is 43

	20000 < x(43+190);

	x > 20000/233;

	x ~> 84;

After ~84 messages, pressure state is entered and 0 rwnd is advertised while
received 84*43B ~= 3612B sctp data. This is why external observer notices sudden
drop from 6474 to 0, as it will be now shown in example:

IP A.34340 > B.12345: sctp (1) [INIT] [init tag: 1875509148] [rwnd: 81920] [OS: 10] [MIS: 65535] [init TSN: 1096057017]
IP B.12345 > A.34340: sctp (1) [INIT ACK] [init tag: 3198966556] [rwnd: 10000] [OS: 10] [MIS: 10] [init TSN: 902132839]
IP A.34340 > B.12345: sctp (1) [COOKIE ECHO]
IP B.12345 > A.34340: sctp (1) [COOKIE ACK]
IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057017] [SID: 0] [SSEQ 0] [PPID 0x18]
IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057017] [a_rwnd 9957] [#gap acks 0] [#dup tsns 0]
IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057018] [SID: 0] [SSEQ 1] [PPID 0x18]
IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057018] [a_rwnd 9957] [#gap acks 0] [#dup tsns 0]
IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057019] [SID: 0] [SSEQ 2] [PPID 0x18]
IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057019] [a_rwnd 9914] [#gap acks 0] [#dup tsns 0]
<...>
IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057098] [SID: 0] [SSEQ 81] [PPID 0x18]
IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057098] [a_rwnd 6517] [#gap acks 0] [#dup tsns 0]
IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057099] [SID: 0] [SSEQ 82] [PPID 0x18]
IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057099] [a_rwnd 6474] [#gap acks 0] [#dup tsns 0]
IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057100] [SID: 0] [SSEQ 83] [PPID 0x18]

--> Sudden drop

IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057100] [a_rwnd 0] [#gap acks 0] [#dup tsns 0]

At this point, rwnd_press stores current rwnd value so it can be later restored
in sctp_assoc_rwnd_increase. This however doesn't happen as condition to start
slowly increasing rwnd until rwnd_press is returned to rwnd is never met. This
condition is not met since rwnd, after it hit 0, must first reach rwnd_press by
adding amount which is read from userspace. Let us observe values in above
example. Initial a_rwnd is 10000, pressure was hit when rwnd was ~6500 and the
amount of actual sctp data currently waiting to be delivered to userspace
is ~3500. When userspace starts to read, sctp_assoc_rwnd_increase will be blamed
only for sctp data, which is ~3500. Condition is never met, and when userspace
reads all data, rwnd stays on 3569.

IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057100] [a_rwnd 1505] [#gap acks 0] [#dup tsns 0]
IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057100] [a_rwnd 3010] [#gap acks 0] [#dup tsns 0]
IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057101] [SID: 0] [SSEQ 84] [PPID 0x18]
IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057101] [a_rwnd 3569] [#gap acks 0] [#dup tsns 0]

--> At this point userspace read everything, rwnd recovered only to 3569

IP A.34340 > B.12345: sctp (1) [DATA] (B)(E) [TSN: 1096057102] [SID: 0] [SSEQ 85] [PPID 0x18]
IP B.12345 > A.34340: sctp (1) [SACK] [cum ack 1096057102] [a_rwnd 3569] [#gap acks 0] [#dup tsns 0]

Reproduction is straight forward, it is enough for sender to send packets of
size less then sizeof(struct sk_buff) and receiver keeping them in its buffers.

2) Minute size window for associations sharing the same socket buffer

In case multiple associations share the same socket, and same socket buffer
(sctp.rcvbuf_policy == 0), different scenarios exist in which congestion on one
of the associations can permanently drop rwnd of other association(s).

Situation will be typically observed as one association suddenly having rwnd
dropped to size of last packet received and never recovering beyond that point.
Different scenarios will lead to it, but all have in common that one of the
associations (let it be association from 1)) nearly depleted socket buffer, and
the other association blames socket buffer just for the amount enough to start
the pressure. This association will enter pressure state, set rwnd_press and
announce 0 rwnd.
When data is read by userspace, similar situation as in 1) will occur, rwnd will
increase just for the size read by userspace but rwnd_press will be high enough
so that association doesn't have enough credit to reach rwnd_press and restore
to previous state. This case is special case of 1), being worse as there is, in
the worst case, only one packet in buffer for which size rwnd will be increased.
Consequence is association which has very low maximum rwnd ('minute size', in
our case down to 43B - size of packet which caused pressure) and as such
unusable.

Scenario happened in the field and labs frequently after congestion state (link
breaks, different probabilities of packet drop, packet reordering) and with
scenario 1) preceding. Here is given a deterministic scenario for reproduction:

>From node A establish two associations on the same socket, with rcvbuf_policy
being set to share one common buffer (sctp.rcvbuf_policy == 0). On association 1
repeat scenario from 1), that is, bring it down to 0 and restore up. Observe
scenario 1). Use small payload size (here we use 43). Once rwnd is 'recovered',
bring it down close to 0, as in just one more packet would close it. This has as
a consequence that association number 2 is able to receive (at least) one more
packet which will bring it in pressure state. E.g. if association 2 had rwnd of
10000, packet received was 43, and we enter at this point into pressure,
rwnd_press will have 9957. Once payload is delivered to userspace, rwnd will
increase for 43, but conditions to restore rwnd to original state, just as in
1), will never be satisfied.

--> Association 1, between A.y and B.12345

IP A.55915 > B.12345: sctp (1) [INIT] [init tag: 836880897] [rwnd: 10000] [OS: 10] [MIS: 65535] [init TSN: 4032536569]
IP B.12345 > A.55915: sctp (1) [INIT ACK] [init tag: 2873310749] [rwnd: 81920] [OS: 10] [MIS: 10] [init TSN: 3799315613]
IP A.55915 > B.12345: sctp (1) [COOKIE ECHO]
IP B.12345 > A.55915: sctp (1) [COOKIE ACK]

--> Association 2, between A.z and B.12346

IP A.55915 > B.12346: sctp (1) [INIT] [init tag: 534798321] [rwnd: 10000] [OS: 10] [MIS: 65535] [init TSN: 2099285173]
IP B.12346 > A.55915: sctp (1) [INIT ACK] [init tag: 516668823] [rwnd: 81920] [OS: 10] [MIS: 10] [init TSN: 3676403240]
IP A.55915 > B.12346: sctp (1) [COOKIE ECHO]
IP B.12346 > A.55915: sctp (1) [COOKIE ACK]

--> Deplete socket buffer by sending messages of size 43B over association 1

IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315613] [SID: 0] [SSEQ 0] [PPID 0x18]
IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315613] [a_rwnd 9957] [#gap acks 0] [#dup tsns 0]

<...>

IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315696] [a_rwnd 6388] [#gap acks 0] [#dup tsns 0]
IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315697] [SID: 0] [SSEQ 84] [PPID 0x18]
IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315697] [a_rwnd 6345] [#gap acks 0] [#dup tsns 0]

--> Sudden drop on 1

IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315698] [SID: 0] [SSEQ 85] [PPID 0x18]
IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315698] [a_rwnd 0] [#gap acks 0] [#dup tsns 0]

--> Here userspace read, rwnd 'recovered' to 3698, now deplete again using
    association 1 so there is place in buffer for only one more packet

IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315799] [SID: 0] [SSEQ 186] [PPID 0x18]
IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315799] [a_rwnd 86] [#gap acks 0] [#dup tsns 0]
IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315800] [SID: 0] [SSEQ 187] [PPID 0x18]
IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315800] [a_rwnd 43] [#gap acks 0] [#dup tsns 0]

--> Socket buffer is almost depleted, but there is space for one more packet,
    send them over association 2, size 43B

IP B.12346 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3676403240] [SID: 0] [SSEQ 0] [PPID 0x18]
IP A.55915 > B.12346: sctp (1) [SACK] [cum ack 3676403240] [a_rwnd 0] [#gap acks 0] [#dup tsns 0]

--> Immediate drop

IP A.60995 > B.12346: sctp (1) [SACK] [cum ack 387491510] [a_rwnd 0] [#gap acks 0] [#dup tsns 0]

--> Read everything from the socket, both association recover up to maximum rwnd
    they are capable of reaching, note that association 1 recovered up to 3698,
    and association 2 recovered only to 43

IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315800] [a_rwnd 1548] [#gap acks 0] [#dup tsns 0]
IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315800] [a_rwnd 3053] [#gap acks 0] [#dup tsns 0]
IP B.12345 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3799315801] [SID: 0] [SSEQ 188] [PPID 0x18]
IP A.55915 > B.12345: sctp (1) [SACK] [cum ack 3799315801] [a_rwnd 3698] [#gap acks 0] [#dup tsns 0]
IP B.12346 > A.55915: sctp (1) [DATA] (B)(E) [TSN: 3676403241] [SID: 0] [SSEQ 1] [PPID 0x18]
IP A.55915 > B.12346: sctp (1) [SACK] [cum ack 3676403241] [a_rwnd 43] [#gap acks 0] [#dup tsns 0]

A careful reader might wonder why it is necessary to reproduce 1) prior
reproduction of 2). It is simply easier to observe when to send packet over
association 2 which will push association into the pressure state.

Proposed solution:

Both problems share the same root cause, and that is improper scaling of socket
buffer with rwnd. Solution in which sizeof(sk_buff) is taken into concern while
calculating rwnd is not possible due to fact that there is no linear
relationship between amount of data blamed in increase/decrease with IP packet
in which payload arrived. Even in case such solution would be followed,
complexity of the code would increase. Due to nature of current rwnd handling,
slow increase (in sctp_assoc_rwnd_increase) of rwnd after pressure state is
entered is rationale, but it gives false representation to the sender of current
buffer space. Furthermore, it implements additional congestion control mechanism
which is defined on implementation, and not on standard basis.

Proposed solution simplifies whole algorithm having on mind definition from rfc:

o  Receiver Window (rwnd): This gives the sender an indication of the space
   available in the receiver's inbound buffer.

Core of the proposed solution is given with these lines:

sctp_assoc_rwnd_update:
	if ((asoc->base.sk->sk_rcvbuf - rx_count) > 0)
		asoc->rwnd = (asoc->base.sk->sk_rcvbuf - rx_count) >> 1;
	else
		asoc->rwnd = 0;

We advertise to sender (half of) actual space we have. Half is in the braces
depending whether you would like to observe size of socket buffer as SO_RECVBUF
or twice the amount, i.e. size is the one visible from userspace, that is,
from kernelspace.
In this way sender is given with good approximation of our buffer space,
regardless of the buffer policy - we always advertise what we have. Proposed
solution fixes described problems and removes necessity for rwnd restoration
algorithm. Finally, as proposed solution is simplification, some lines of code,
along with some bytes in struct sctp_association are saved.

Version 2 of the patch addressed comments from Vlad. Name of the function is set
to be more descriptive, and two parts of code are changed, in one removing the
superfluous call to sctp_assoc_rwnd_update since call would not result in update
of rwnd, and the other being reordering of the code in a way that call to
sctp_assoc_rwnd_update updates rwnd. Version 3 corrected change introduced in v2
in a way that existing function is not reordered/copied in line, but it is
correctly called. Thanks Vlad for suggesting.

Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nsn.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-17 00:16:56 -05:00
stephen hemminger 2045ceaed4 net: remove unnecessary return's
One of my pet coding style peeves is the practice of
adding extra return; at the end of function.
Kill several instances of this in network code.

I suppose some coccinelle wizardy could do this automatically.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 18:33:38 -05:00
wangweidong efb842c45e sctp: optimize the sctp_sysctl_net_register
Here, when the net is init_net, we needn't to kmemdup the ctl_table
again. So add a check for net. Also we can save some memory.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 17:08:29 -05:00
wangweidong 22a1f5140e sctp: fix a missed .data initialization
As commit 3c68198e75111a90("sctp: Make hmac algorithm selection for
 cookie generation dynamic"), we miss the .data initialization.
If we don't use the net_namespace, the problem that parts of the
sysctl configuration won't be isolation and won't occur.

In sctp_sysctl_net_register(), we register the sysctl for each
net, in the for(), we use the 'table[i].data' as check condition, so
when the 'i' is the index of sctp_hmac_alg, the data is NULL, then
break. So add the .data initialization.

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 17:08:29 -05:00
Matija Glavinic Pecotic 661dbf3412 net: sctp: fix initialization of local source address on accepted ipv6 sockets
commit 	efe4208f47f907b86f528788da711e8ab9dea44d:
'ipv6: make lookups simpler and faster' broke initialization of local source
address on accepted ipv6 sockets. Before the mentioned commit receive address
was copied along with the contents of ipv6_pinfo in sctp_v6_create_accept_sk.
Now when it is moved, it has to be copied separately.

This also fixes lksctp's ipv6 regression in a sense that test_getname_v6, TC5 -
'getsockname on a connected server socket' now passes.

Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nsn.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-06 21:18:06 -08:00
wangweidong 5bc1d1b4a2 sctp: remove macros sctp_bh_[un]lock_sock
Redefined bh_[un]lock_sock to sctp_bh[un]lock_sock for user
space friendly code which we haven't use in years, so removing them.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 18:41:36 -08:00
wangweidong 048ed4b626 sctp: remove macros sctp_{lock|release}_sock
Redefined {lock|release}_sock to sctp_{lock|release}_sock for user space friendly
code which we haven't use in years, so removing them.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 18:41:36 -08:00
wangweidong 387602dfdc sctp: remove macros sctp_write_[un]_lock
Redefined write_[un]lock to sctp_write_[un]lock for user space
friendly code which we haven't use in years, so removing them.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 18:40:41 -08:00
wangweidong 3c8e43ba9f sctp: remove macros sctp_spin_[un]lock
Redefined spin_[un]lock to sctp_spin_[un]lock for user space friendly
code which we haven't use in years, so removing them.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 18:40:41 -08:00
wangweidong 79b91130a2 sctp: remove macros sctp_local_bh_{disable|enable}
Redefined local_bh_{disable|enable} to sctp_local_bh_{disable|enable}
for user space friendly code which we haven't use in years, so removing them.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 18:40:40 -08:00
wangweidong abfce3ef58 sctp: remove the unnecessary assignment
When go the right path, the status is 0, no need to assign it again.
So just remove the assignment.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 17:31:49 -08:00
wangweidong 0ea5e4df7b sctp: create helper function to enable|disable sackdelay
add sctp_spp_sackdelay_{enable|disable} helper function for
avoiding code duplication.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-15 16:47:48 -08:00
Dan Carpenter 0e864b21e5 sctp: remove a redundant NULL check
It confuses Smatch when we check "sinit" for NULL and then non-NULL and
that causes a false positive warning later.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14 18:18:22 -08:00
Aruna-Hewapathirane 63862b5bef net: replace macros net_random and net_srandom with direct calls to prandom
This patch removes the net_random and net_srandom macros and replaces
them with direct calls to the prandom ones. As new commits only seem to
use prandom_u32 there is no use to keep them around.
This change makes it easier to grep for users of prandom_u32.

Signed-off-by: Aruna-Hewapathirane <aruna.hewapathirane@gmail.com>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14 15:15:25 -08:00
stephen hemminger 6daaf0de2f sctp: make sctp_addto_chunk_fixed local
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13 14:42:30 -08:00
Hannes Frederic Sowa 8ed1dc44d3 ipv4: introduce hardened ip_no_pmtu_disc mode
This new ip_no_pmtu_disc mode only allowes fragmentation-needed errors
to be honored by protocols which do more stringent validation on the
ICMP's packet payload. This knob is useful for people who e.g. want to
run an unmodified DNS server in a namespace where they need to use pmtu
for TCP connections (as they are used for zone transfers or fallback
for requests) but don't want to use possibly spoofed UDP pmtu information.

Currently the whitelisted protocols are TCP, SCTP and DCCP as they check
if the returned packet is in the window or if the association is valid.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: John Heffner <johnwheffner@gmail.com>
Suggested-by: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13 11:22:55 -08:00
David S. Miller 56a4342dfe Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/qlogic/qlcnic/qlcnic_sriov_pf.c
	net/ipv6/ip6_tunnel.c
	net/ipv6/ip6_vti.c

ipv6 tunnel statistic bug fixes conflicting with consolidation into
generic sw per-cpu net stats.

qlogic conflict between queue counting bug fix and the addition
of multiple MAC address support.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-06 17:37:45 -05:00
Neil Horman f916ec9608 sctp: Add process name and pid to deprecation warnings
Recently I updated the sctp socket option deprecation warnings to be both a bit
more clear and ratelimited to prevent user processes from spamming the log file.
Ben Hutchings suggested that I add the process name and pid to these warnings so
that users can tell who is responsible for using the deprecated apis.  This
patch accomplishes that.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-03 19:36:46 -05:00
Vlad Yasevich 619a60ee04 sctp: Remove outqueue empty state
The SCTP outqueue structure maintains a data chunks
that are pending transmission, the list of chunks that
are pending a retransmission and a length of data in
flight.  It also tries to keep the emtpy state so that
it can performe shutdown sequence or notify user.

The problem is that the empy state is inconsistently
tracked.  It is possible to completely drain the queue
without sending anything when using PR-SCTP.  In this
case, the empty state will not be correctly state as
report by Jamal Hadi Salim <jhs@mojatatu.com>.  This
can cause an association to be perminantly stuck in the
SHUTDOWN_PENDING state.

Additionally, SCTP is incredibly inefficient when setting
the empty state.  Even though all the data is availaible
in the outqueue structure, we ignore it and walk a list
of trasnports.

In the end, we can completely remove the extra empty
state and figure out if the queue is empty by looking
at 3 things:  length of pending data, length of in-flight
data, and exisiting of retransmit data.  All of these
are already in the strucutre.

Reported-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Tested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-02 17:22:48 -05:00
wangweidong 0438816efd sctp: move skb_dst_set() a bit downwards in sctp_packet_transmit()
skb_dst_set will use dst, if dst is NULL although is not a problem,
then goto the 'no_route' and free nskb, so do the skb_dst_set is pointless.
so move the skb_dst_set after dst check.
Remove the unnecessary initialization as well.

v2: fix the subject line because it would confuse people,
    as pointed out by Daniel.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-31 14:31:44 -05:00
Neil Horman 94f65193ab SCTP: Reduce log spamming for sctp setsockopt
During a recent discussion regarding some sctp socket options, it was noted that
we have several points at which we issue log warnings that can be flooded at an
unbounded rate by any user.  Fix this by converting all the pr_warns in the
sctp_setsockopt path to be pr_warn_ratelimited.

Note there are several debug level messages as well.  I'm leaving those alone,
as, if you turn on pr_debug, you likely want lots of verbosity.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: David Miller <davem@davemloft.net>
CC: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-31 13:58:40 -05:00
wangweidong 4e2d52bfb2 sctp: fix checkpatch errors with //commen
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-26 13:47:48 -05:00
wangweidong 8d72651d86 sctp: fix checkpatch errors with open brace '{' and trailing statements
fix checkpatch errors below:
ERROR: that open brace { should be on the previous line
ERROR: open brace '{' following function declarations go on the next line
ERROR: trailing statements should be on next line

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-26 13:47:48 -05:00
wangweidong f7010e6144 sctp: fix checkpatch errors with indent
fix checkpatch errors below:
ERROR: switch and case should be at the same inden
ERROR: code indent should use tabs where possible

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-26 13:47:48 -05:00
wangweidong 26ac8e5fe1 sctp: fix checkpatch errors with (foo*)|foo * bar|foo* bar
fix checkpatch errors below:
ERROR: "(foo*)" should be "(foo *)"
ERROR: "foo * bar" should be "foo *bar"
ERROR: "foo* bar" should be "foo *bar"

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-26 13:47:47 -05:00
wangweidong cb3f837ba9 sctp: fix checkpatch errors with space required or prohibited
fix checkpatch errors while the space is required or prohibited
to the "=,()++..."

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-26 13:47:47 -05:00
wangweidong f482f2fcd1 sctp: remove the never used 'return' and redundant 'break'
In switch() had do return, and never use the 'return NULL'. The
'break' after return or goto has no effect. Remove it.

v2: make it more readable as suggested by Neil.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-22 18:56:51 -05:00
wangweidong 131334d09c sctp: remove casting from function calls through ops structure
remove the unnecessary cast.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-22 18:04:28 -05:00
Hannes Frederic Sowa 790e38bc26 ipv6: move ip6_sk_accept_pmtu from generic pmtu update path to ipv6 one
In commit 93b36cf342 ("ipv6: support IPV6_PMTU_INTERFACE on sockets")
I made a horrible mistake to add ip6_sk_accept_pmtu to the generic
sctp_icmp_frag_needed path. This results in build warnings if IPv6 is
disabled which were luckily caught by Fengguang's kbuild bot. But it
also leads to a kernel panic IPv4 frag-needed packet is received.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-21 22:00:59 -05:00
David S. Miller fc45b45540 Revert "sctp: fix missing include file"
This reverts commit ac0917f250.

Better version of this fix forthcoming.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-21 22:00:39 -05:00
sfeldma@cumulusnetworks.com ac0917f250 sctp: fix missing include file
Compile error reported by Jim Davis on netdev.

ip6_sk_accept_pmtu() needs net/ip6_route.h

Signed-off-by: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-21 00:00:33 -05:00
David S. Miller 1669cb9855 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2013-12-19

1) Use the user supplied policy index instead of a generated one
   if present. From Fan Du.

2) Make xfrm migration namespace aware. From Fan Du.

3) Make the xfrm state and policy locks namespace aware. From Fan Du.

4) Remove ancient sleeping when the SA is in acquire state,
   we now queue packets to the policy instead. This replaces the
   sleeping code.

5) Remove FLOWI_FLAG_CAN_SLEEP. This was used to notify xfrm about the
   posibility to sleep. The sleeping code is gone, so remove it.

6) Check user specified spi for IPComp. Thr spi for IPcomp is only
   16 bit wide, so check for a valid value. From Fan Du.

7) Export verify_userspi_info to check for valid user supplied spi ranges
   with pfkey and netlink. From Fan Du.

8) RFC3173 states that if the total size of a compressed payload and the IPComp
   header is not smaller than the size of the original payload, the IP datagram
   must be sent in the original non-compressed form. These packets are dropped
   by the inbound policy check because they are not transformed. Document the need
   to set 'level use' for IPcomp to receive such packets anyway. From Fan Du.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-19 18:37:49 -05:00
Hannes Frederic Sowa 93b36cf342 ipv6: support IPV6_PMTU_INTERFACE on sockets
IPV6_PMTU_INTERFACE is the same as IPV6_PMTU_PROBE for ipv6. Add it
nontheless for symmetry with IPv4 sockets. Also drop incoming MTU
information if this mode is enabled.

The additional bit in ipv6_pinfo just eats in the padding behind the
bitfield. There are no changes to the layout of the struct at all.

Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18 17:37:05 -05:00
David S. Miller 143c905494 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/intel/i40e/i40e_main.c
	drivers/net/macvtap.c

Both minor merge hassles, simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18 16:42:06 -05:00
wangweidong 9bd7d20c45 sctp: loading sctp when load sctp_probe
when I modprobe sctp_probe, it failed with "FATAL: ". I found that
sctp should load before sctp_probe register jprobe. So I add a
sctp_setup_jprobe for loading 'sctp' when first failed to register
jprobe, just do this similar to dccp_probe.

v2: add MODULE_SOFTDEP and check of request_module, as suggested by Neil

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-16 20:04:27 -05:00
wangweidong e477266838 sctp: remove redundant null check on asoc
In sctp_err_lookup, goto out while the asoc is not NULL, so remove the
check NULL. Also, in sctp_err_finish which called by sctp_v4_err and
sctp_v6_err, they pass asoc to sctp_err_finish while the asoc is not
NULL, so remove the check.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11 15:39:34 -05:00
wangweidong b486b2289e sctp: fix up a spacing
fix up spacing of proc_sctp_do_hmac_alg for according to the
proc_sctp_do_rto_min[max] in sysctl.c

Suggested-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10 22:54:34 -05:00
wangweidong 4f3fdf3bc5 sctp: add check rto_min and rto_max in sysctl
rto_min should be smaller than rto_max while rto_max should be larger
than rto_min. Add two proc_handler for the checking.

Suggested-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10 22:54:34 -05:00
wangweidong 85f935d41a sctp: check the rto_min and rto_max in setsockopt
When we set 0 to rto_min or rto_max, just not change the value. Also
we should check the rto_min > rto_max.

Suggested-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10 22:54:34 -05:00
Neil Horman 9f70f46bd4 sctp: properly latch and use autoclose value from sock to association
Currently, sctp associations latch a sockets autoclose value to an association
at association init time, subject to capping constraints from the max_autoclose
sysctl value.  This leads to an odd situation where an application may set a
socket level autoclose timeout, but sliently sctp will limit the autoclose
timeout to something less than that.

Fix this by modifying the autoclose setsockopt function to check the limit, cap
it and warn the user via syslog that the timeout is capped.  This will allow
getsockopt to return valid autoclose timeout values that reflect what subsequent
associations actually use.

While were at it, also elimintate the assoc->autoclose variable, it duplicates
whats in the timeout array, which leads to multiple sources for the same
information, that may differ (as the former isn't subject to any capping).  This
gives us the timeout information in a canonical place and saves some space in
the association structure as well.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
CC: Wang Weidong <wangweidong1@huawei.com>
CC: David Miller <davem@davemloft.net>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10 22:41:26 -05:00
David S. Miller 34f9f43710 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge 'net' into 'net-next' to get the AF_PACKET bug fix that
Daniel's direct transmit changes depend upon.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09 20:20:14 -05:00
wangweidong 9d2c881afd sctp: fix some comments in associola.c
fix some typos

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 14:54:39 -05:00
wangweidong ce4a03db9b sctp: convert sctp_peer_needs_update to boolean
sctp_peer_needs_update only return 0 or 1.

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 14:54:39 -05:00
wangweidong 8b7318d3ed sctp: remove the else path
Make the code more simplification.

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 14:54:38 -05:00
wangweidong d1d66186dc sctp: remove the duplicate initialize
kzalloc had initialize the allocated memroy. Therefore, remove the
initialize with 0 and the memset.

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 14:54:38 -05:00
Jeff Kirsher 4b2f13a251 sctp: Fix FSF address in file headers
Several files refer to an old address for the Free Software Foundation
in the file header comment.  Resolve by replacing the address with
the URL <http://www.gnu.org/licenses/> so that we do not have to keep
updating the header comments anytime the address changes.

CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 12:37:56 -05:00
Steffen Klassert 0e0d44ab42 net: Remove FLOWI_FLAG_CAN_SLEEP
FLOWI_FLAG_CAN_SLEEP was used to notify xfrm about the posibility
to sleep until the needed states are resolved. This code is gone,
so FLOWI_FLAG_CAN_SLEEP is not needed anymore.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-12-06 07:24:39 +01:00
wangweidong 78ac814f12 sctp: disable max_burst when the max_burst is 0
As Michael pointed out that when max_burst is 0, it just disable
max_burst. It declared in rfc6458#section-8.1.24. so add the check
in sctp_transport_burst_limited, when it 0, just do nothing.

Reviewed-by: Daniel Borkmann <dborkman@redhat.com>
Suggested-by: Vlad Yasevich <vyasevich@gmail.com>
Suggested-by: Michael Tuexen <Michael.Tuexen@lurchi.franken.de>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 20:55:54 -05:00
Xufeng Zhang 6eabca54d6 sctp: Restore 'resent' bit to avoid retransmitted chunks for RTT measurements
Currently retransmitted DATA chunks could also be used for
RTT measurements since there are no flag to identify whether
the transmitted DATA chunk is a new one or a retransmitted one.
This problem is introduced by commit ae19c5486 ("sctp: remove
'resent' bit from the chunk") which inappropriately removed the
'resent' bit completely, instead of doing this, we should set
the resent bit only for the retransmitted DATA chunks.

Signed-off-by: Xufeng Zhang <xufeng.zhang@windriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-28 18:29:58 -05:00
Chang Xiangzhong d6c4161485 net: sctp: find the correct highest_new_tsn in sack
Function sctp_check_transmitted(transport t, ...) would iterate all of
transport->transmitted queue and looking for the highest __newly__ acked tsn.
The original algorithm would depend on the order of the assoc->transport_list
(in function sctp_outq_sack line 1215 - 1226). The result might not be the
expected due to the order of the tranport_list.

Solution: checking if the exising is smaller than the new one before assigning

Signed-off-by: Chang Xiangzhong <changxiangzhong@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-23 14:46:18 -08:00
Linus Torvalds 1ee2dcc224 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "Mostly these are fixes for fallout due to merge window changes, as
  well as cures for problems that have been with us for a much longer
  period of time"

 1) Johannes Berg noticed two major deficiencies in our genetlink
    registration.  Some genetlink protocols we passing in constant
    counts for their ops array rather than something like
    ARRAY_SIZE(ops) or similar.  Also, some genetlink protocols were
    using fixed IDs for their multicast groups.

    We have to retain these fixed IDs to keep existing userland tools
    working, but reserve them so that other multicast groups used by
    other protocols can not possibly conflict.

    In dealing with these two problems, we actually now use less state
    management for genetlink operations and multicast groups.

 2) When configuring interface hardware timestamping, fix several
    drivers that simply do not validate that the hwtstamp_config value
    is one the driver actually supports.  From Ben Hutchings.

 3) Invalid memory references in mwifiex driver, from Amitkumar Karwar.

 4) In dev_forward_skb(), set the skb->protocol in the right order
    relative to skb_scrub_packet().  From Alexei Starovoitov.

 5) Bridge erroneously fails to use the proper wrapper functions to make
    calls to netdev_ops->ndo_vlan_rx_{add,kill}_vid.  Fix from Toshiaki
    Makita.

 6) When detaching a bridge port, make sure to flush all VLAN IDs to
    prevent them from leaking, also from Toshiaki Makita.

 7) Put in a compromise for TCP Small Queues so that deep queued devices
    that delay TX reclaim non-trivially don't have such a performance
    decrease.  One particularly problematic area is 802.11 AMPDU in
    wireless.  From Eric Dumazet.

 8) Fix crashes in tcp_fastopen_cache_get(), we can see NULL socket dsts
    here.  Fix from Eric Dumzaet, reported by Dave Jones.

 9) Fix use after free in ipv6 SIT driver, from Willem de Bruijn.

10) When computing mergeable buffer sizes, virtio-net fails to take the
    virtio-net header into account.  From Michael Dalton.

11) Fix seqlock deadlock in ip4_datagram_connect() wrt.  statistic
    bumping, this one has been with us for a while.  From Eric Dumazet.

12) Fix NULL deref in the new TIPC fragmentation handling, from Erik
    Hugne.

13) 6lowpan bit used for traffic classification was wrong, from Jukka
    Rissanen.

14) macvlan has the same issue as normal vlans did wrt.  propagating LRO
    disabling down to the real device, fix it the same way.  From Michal
    Kubecek.

15) CPSW driver needs to soft reset all slaves during suspend, from
    Daniel Mack.

16) Fix small frame pacing in FQ packet scheduler, from Eric Dumazet.

17) The xen-netfront RX buffer refill timer isn't properly scheduled on
    partial RX allocation success, from Ma JieYue.

18) When ipv6 ping protocol support was added, the AF_INET6 protocol
    initialization cleanup path on failure was borked a little.  Fix
    from Vlad Yasevich.

19) If a socket disconnects during a read/recvmsg/recvfrom/etc that
    blocks we can do the wrong thing with the msg_name we write back to
    userspace.  From Hannes Frederic Sowa.  There is another fix in the
    works from Hannes which will prevent future problems of this nature.

20) Fix route leak in VTI tunnel transmit, from Fan Du.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (106 commits)
  genetlink: make multicast groups const, prevent abuse
  genetlink: pass family to functions using groups
  genetlink: add and use genl_set_err()
  genetlink: remove family pointer from genl_multicast_group
  genetlink: remove genl_unregister_mc_group()
  hsr: don't call genl_unregister_mc_group()
  quota/genetlink: use proper genetlink multicast APIs
  drop_monitor/genetlink: use proper genetlink multicast APIs
  genetlink: only pass array to genl_register_family_with_ops()
  tcp: don't update snd_nxt, when a socket is switched from repair mode
  atm: idt77252: fix dev refcnt leak
  xfrm: Release dst if this dst is improper for vti tunnel
  netlink: fix documentation typo in netlink_set_err()
  be2net: Delete secondary unicast MAC addresses during be_close
  be2net: Fix unconditional enabling of Rx interface options
  net, virtio_net: replace the magic value
  ping: prevent NULL pointer dereference on write to msg_name
  bnx2x: Prevent "timeout waiting for state X"
  bnx2x: prevent CFC attention
  bnx2x: Prevent panic during DMAE timeout
  ...
2013-11-19 15:50:47 -08:00
Tetsuo Handa 652586df95 seq_file: remove "%n" usage from seq_file users
All seq_printf() users are using "%n" for calculating padding size,
convert them to use seq_setwidth() / seq_pad() pair.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 09:32:20 +09:00
Chang Xiangzhong d30a58ba2e net: sctp: bug-fixing: retran_path not set properly after transports recovering (v3)
When a transport recovers due to the new coming sack, SCTP should
iterate all of its transport_list to locate the __two__ most recently used
transport and set to active_path and retran_path respectively. The exising
code does not find the two properly - In case of the following list:

[most-recent] -> [2nd-most-recent] -> ...

Both active_path and retran_path would be set to the 1st element.

The bug happens when:
1) multi-homing
2) failure/partial_failure transport recovers
Both active_path and retran_path would be set to the same most-recent one, in
other words, retran_path would not take its role - an end user might not even
notice this issue.

Signed-off-by: Chang Xiangzhong <changxiangzhong@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14 16:35:09 -05:00
David S. Miller 394efd19d5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/emulex/benet/be.h
	drivers/net/netconsole.c
	net/bridge/br_private.h

Three mostly trivial conflicts.

The net/bridge/br_private.h conflict was a function signature (argument
addition) change overlapping with the extern removals from Joe Perches.

In drivers/net/netconsole.c we had one change adjusting a printk message
whilst another changed "printk(KERN_INFO" into "pr_info(".

Lastly, the emulex change was a new inline function addition overlapping
with Joe Perches's extern removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-04 13:48:30 -05:00
Daniel Borkmann 7926c1d5be net: sctp: do not trigger BUG_ON in sctp_cmd_delete_tcb
Introduced in f9e42b8535 ("net: sctp: sideeffect: throw BUG if
primary_path is NULL"), we intended to find a buggy assoc that's
part of the assoc hash table with a primary_path that is NULL.
However, we better remove the BUG_ON for now and find a more
suitable place to assert for these things as Mark reports that
this also triggers the bug when duplication cookie processing
happens, and the assoc is not part of the hash table (so all
good in this case). Such a situation can for example easily be
reproduced by:

  tc qdisc add dev eth0 root handle 1: prio bands 2 priomap 1 1 1 1 1 1
  tc qdisc add dev eth0 parent 1:2 handle 20: netem loss 20%
  tc filter add dev eth0 protocol ip parent 1: prio 2 u32 match ip \
            protocol 132 0xff match u8 0x0b 0xff at 32 flowid 1:2

This drops 20% of COOKIE-ACK packets. After some follow-up
discussion with Vlad we came to the conclusion that for now we
should still better remove this BUG_ON() assertion, and come up
with two follow-ups later on, that is, i) find a more suitable
place for this assertion, and possibly ii) have a special
allocator/initializer for such kind of temporary assocs.

Reported-by: Mark Thomas <Mark.Thomas@metaswitch.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-04 00:46:44 -05:00
Daniel Borkmann e6d8b64b34 net: sctp: fix and consolidate SCTP checksumming code
This fixes an outstanding bug found through IPVS, where SCTP packets
with skb->data_len > 0 (non-linearized) and empty frag_list, but data
accumulated in frags[] member, are forwarded with incorrect checksum
letting SCTP initial handshake fail on some systems. Linearizing each
SCTP skb in IPVS to prevent that would not be a good solution as
this leads to an additional and unnecessary performance penalty on
the load-balancer itself for no good reason (as we actually only want
to update the checksum, and can do that in a different/better way
presented here).

The actual problem is elsewhere, namely, that SCTP's checksumming
in sctp_compute_cksum() does not take frags[] into account like
skb_checksum() does. So while we are fixing this up, we better reuse
the existing code that we have anyway in __skb_checksum() and use it
for walking through the data doing checksumming. This will not only
fix this issue, but also consolidates some SCTP code with core
sk_buff code, bringing it closer together and removing respectively
avoiding reimplementation of skb_checksum() for no good reason.

As crc32c() can use hardware implementation within the crypto layer,
we leave that intact (it wraps around / falls back to e.g. slice-by-8
algorithm in __crc32c_le() otherwise); plus use the __crc32c_le_combine()
combinator for crc32c blocks.

Also, we remove all other SCTP checksumming code, so that we only
have to use sctp_compute_cksum() from now on; for doing that, we need
to transform SCTP checkumming in output path slightly, and can leave
the rest intact.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-03 23:04:57 -05:00
wangweidong 747edc0f9e sctp: merge two if statements to one
Two if statements do the same work, we can merge them to
one. And fix some typos. There is just code simplification,
no functional changes.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-28 01:02:34 -04:00
wangweidong 3dc0a548a0 sctp: remove the repeat initialize with 0
kmem_cache_zalloc had set the allocated memory to zero. I think no need
to initialize with 0. And move the comments to the function begin.

Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-28 01:02:34 -04:00
wangweidong 2bccbadf20 sctp: fix some comments in chunk.c and associola.c
fix some typos

Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-28 01:02:34 -04:00
Daniel Borkmann fecda03493 net: sctp: fix ASCONF to allow non SCTP_ADDR_SRC addresses in ipv6
Commit 8a07eb0a50 ("sctp: Add ASCONF operation on the single-homed host")
implemented possible use of IPv4 addresses with non SCTP_ADDR_SRC state
as source address when sending ASCONF (ADD) packets, but IPv6 part for
that was not implemented in 8a07eb0a50. Therefore, as this is not restricted
to IPv4-only, fix this up to allow the same for IPv6 addresses in SCTP.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Michio Honda <micchie@sfc.wide.ad.jp>
Acked-by: Michio Honda <micchie@sfc.wide.ad.jp>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:57:14 -04:00
David S. Miller c3fa32b976 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/qmi_wwan.c
	include/net/dst.h

Trivial merge conflicts, both were overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:49:34 -04:00
Vlad Yasevich d2dbbba77e sctp: Perform software checksum if packet has to be fragmented.
IP/IPv6 fragmentation knows how to compute only TCP/UDP checksum.
This causes problems if SCTP packets has to be fragmented and
ipsummed has been set to PARTIAL due to checksum offload support.
This condition can happen when retransmitting after MTU discover,
or when INIT or other control chunks are larger then MTU.
Check for the rare fragmentation condition in SCTP and use software
checksum calculation in this case.

CC: Fan Du <fan.du@windriver.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-17 15:24:44 -04:00
Fan Du 27127a8256 sctp: Use software crc32 checksum when xfrm transform will happen.
igb/ixgbe have hardware sctp checksum support, when this feature is enabled
and also IPsec is armed to protect sctp traffic, ugly things happened as
xfrm_output checks CHECKSUM_PARTIAL to do checksum operation(sum every thing
up and pack the 16bits result in the checksum field). The result is fail
establishment of sctp communication.

Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-17 15:24:44 -04:00
Eric Dumazet efe4208f47 ipv6: make lookups simpler and faster
TCP listener refactoring, part 4 :

To speed up inet lookups, we moved IPv4 addresses from inet to struct
sock_common

Now is time to do the same for IPv6, because it permits us to have fast
lookups for all kind of sockets, including upcoming SYN_RECV.

Getting IPv6 addresses in TCP lookups currently requires two extra cache
lines, plus a dereference (and memory stall).

inet6_sk(sk) does the dereference of inet_sk(__sk)->pinet6

This patch is way bigger than its IPv4 counter part, because for IPv4,
we could add aliases (inet_daddr, inet_rcv_saddr), while on IPv6,
it's not doable easily.

inet6_sk(sk)->daddr becomes sk->sk_v6_daddr
inet6_sk(sk)->rcv_saddr becomes sk->sk_v6_rcv_saddr

And timewait socket also have tw->tw_v6_daddr & tw->tw_v6_rcv_saddr
at the same offset.

We get rid of INET6_TW_MATCH() as INET6_MATCH() is now the generic
macro.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-09 00:01:25 -04:00
Eric W. Biederman 0bbf87d852 net ipv4: Convert ipv4.ip_local_port_range to be per netns v3
- Move sysctl_local_ports from a global variable into struct netns_ipv4.
- Modify inet_get_local_port_range to take a struct net, and update all
  of the callers.
- Move the initialization of sysctl_local_ports into
   sysctl_net_ipv4.c:ipv4_sysctl_init_net from inet_connection_sock.c

v2:
- Ensure indentation used tabs
- Fixed ip.h so it applies cleanly to todays net-next

v3:
- Compile fixes of strange callers of inet_get_local_port_range.
  This patch now successfully passes an allmodconfig build.
  Removed manual inlining of inet_get_local_port_range in ipv4_local_port_range

Originally-by: Samya <samya@twitter.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-30 21:59:38 -07:00
Daniel Borkmann 3f96a53211 net: sctp: rfc4443: do not report ICMP redirects to user space
Adapt the same behaviour for SCTP as present in TCP for ICMP redirect
messages. For IPv6, RFC4443, section 2.4. says:

  ...
  (e) An ICMPv6 error message MUST NOT be originated as a result of
      receiving the following:
  ...
       (e.2) An ICMPv6 redirect message [IPv6-DISC].
  ...

Therefore, do not report an error to user space, just invoke dst's redirect
callback and leave, same for IPv4 as done in TCP as well. The implication
w/o having this patch could be that the reception of such packets would
generate a poll notification and in worst case it could even tear down the
whole connection. Therefore, stop updating sk_err on redirects.

Reported-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Suggested-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-16 21:40:15 -04:00
Daniel Borkmann 95ee62083c net: sctp: fix ipv6 ipsec encryption bug in sctp_v6_xmit
Alan Chester reported an issue with IPv6 on SCTP that IPsec traffic is not
being encrypted, whereas on IPv4 it is. Setting up an AH + ESP transport
does not seem to have the desired effect:

SCTP + IPv4:

  22:14:20.809645 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto AH (51), length 116)
    192.168.0.2 > 192.168.0.5: AH(spi=0x00000042,sumlen=16,seq=0x1): ESP(spi=0x00000044,seq=0x1), length 72
  22:14:20.813270 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto AH (51), length 340)
    192.168.0.5 > 192.168.0.2: AH(spi=0x00000043,sumlen=16,seq=0x1):

SCTP + IPv6:

  22:31:19.215029 IP6 (class 0x02, hlim 64, next-header SCTP (132) payload length: 364)
    fe80::222:15ff:fe87:7fc.3333 > fe80::92e6:baff:fe0d:5a54.36767: sctp
    1) [INIT ACK] [init tag: 747759530] [rwnd: 62464] [OS: 10] [MIS: 10]

Moreover, Alan says:

  This problem was seen with both Racoon and Racoon2. Other people have seen
  this with OpenSwan. When IPsec is configured to encrypt all upper layer
  protocols the SCTP connection does not initialize. After using Wireshark to
  follow packets, this is because the SCTP packet leaves Box A unencrypted and
  Box B believes all upper layer protocols are to be encrypted so it drops
  this packet, causing the SCTP connection to fail to initialize. When IPsec
  is configured to encrypt just SCTP, the SCTP packets are observed unencrypted.

In fact, using `socat sctp6-listen:3333 -` on one end and transferring "plaintext"
string on the other end, results in cleartext on the wire where SCTP eventually
does not report any errors, thus in the latter case that Alan reports, the
non-paranoid user might think he's communicating over an encrypted transport on
SCTP although he's not (tcpdump ... -X):

  ...
  0x0030: 5d70 8e1a 0003 001a 177d eb6c 0000 0000  ]p.......}.l....
  0x0040: 0000 0000 706c 6169 6e74 6578 740a 0000  ....plaintext...

Only in /proc/net/xfrm_stat we can see XfrmInTmplMismatch increasing on the
receiver side. Initial follow-up analysis from Alan's bug report was done by
Alexey Dobriyan. Also thanks to Vlad Yasevich for feedback on this.

SCTP has its own implementation of sctp_v6_xmit() not calling inet6_csk_xmit().
This has the implication that it probably never really got updated along with
changes in inet6_csk_xmit() and therefore does not seem to invoke xfrm handlers.

SCTP's IPv4 xmit however, properly calls ip_queue_xmit() to do the work. Since
a call to inet6_csk_xmit() would solve this problem, but result in unecessary
route lookups, let us just use the cached flowi6 instead that we got through
sctp_v6_get_dst(). Since all SCTP packets are being sent through sctp_packet_transmit(),
we do the route lookup / flow caching in sctp_transport_route(), hold it in
tp->dst and skb_dst_set() right after that. If we would alter fl6->daddr in
sctp_v6_xmit() to np->opt->srcrt, we possibly could run into the same effect
of not having xfrm layer pick it up, hence, use fl6_update_dst() in sctp_v6_get_dst()
instead to get the correct source routed dst entry, which we assign to the skb.

Also source address routing example from 625034113 ("sctp: fix sctp to work with
ipv6 source address routing") still works with this patch! Nevertheless, in RFC5095
it is actually 'recommended' to not use that anyway due to traffic amplification [1].
So it seems we're not supposed to do that anyway in sctp_v6_xmit(). Moreover, if
we overwrite the flow destination here, the lower IPv6 layer will be unable to
put the correct destination address into IP header, as routing header is added in
ipv6_push_nfrag_opts() but then probably with wrong final destination. Things aside,
result of this patch is that we do not have any XfrmInTmplMismatch increase plus on
the wire with this patch it now looks like:

SCTP + IPv6:

  08:17:47.074080 IP6 2620:52:0:102f:7a2b:cbff:fe27:1b0a > 2620:52:0:102f:213:72ff:fe32:7eba:
    AH(spi=0x00005fb4,seq=0x1): ESP(spi=0x00005fb5,seq=0x1), length 72
  08:17:47.074264 IP6 2620:52:0:102f:213:72ff:fe32:7eba > 2620:52:0:102f:7a2b:cbff:fe27:1b0a:
    AH(spi=0x00003d54,seq=0x1): ESP(spi=0x00003d55,seq=0x1), length 296

This fixes Kernel Bugzilla 24412. This security issue seems to be present since
2.6.18 kernels. Lets just hope some big passive adversary in the wild didn't have
its fun with that. lksctp-tools IPv6 regression test suite passes as well with
this patch.

 [1] http://www.secdev.org/conf/IPv6_RH_security-csw07.pdf

Reported-by: Alan Chester <alan.chester@tekelec.com>
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-12 17:24:43 -04:00
Daniel Borkmann 88362ad8f9 net: sctp: fix smatch warning in sctp_send_asconf_del_ip
This was originally reported in [1] and posted by Neil Horman [2], he said:

  Fix up a missed null pointer check in the asconf code. If we don't find
  a local address, but we pass in an address length of more than 1, we may
  dereference a NULL laddr pointer. Currently this can't happen, as the only
  users of the function pass in the value 1 as the addrcnt parameter, but
  its not hot path, and it doesn't hurt to check for NULL should that ever
  be the case.

The callpath from sctp_asconf_mgmt() looks okay. But this could be triggered
from sctp_setsockopt_bindx() call with SCTP_BINDX_REM_ADDR and addrcnt > 1
while passing all possible addresses from the bind list to SCTP_BINDX_REM_ADDR
so that we do *not* find a single address in the association's bind address
list that is not in the packed array of addresses. If this happens when we
have an established association with ASCONF-capable peers, then we could get
a NULL pointer dereference as we only check for laddr == NULL && addrcnt == 1
and call later sctp_make_asconf_update_ip() with NULL laddr.

BUT: this actually won't happen as sctp_bindx_rem() will catch such a case
and return with an error earlier. As this is incredably unintuitive and error
prone, add a check to catch at least future bugs here. As Neil says, its not
hot path. Introduced by 8a07eb0a5 ("sctp: Add ASCONF operation on the
single-homed host").

 [1] http://www.spinics.net/lists/linux-sctp/msg02132.html
 [2] http://www.spinics.net/lists/linux-sctp/msg02133.html

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Michio Honda <micchie@sfc.wide.ad.jp>
Acked-By: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-11 16:10:00 -04:00
Daniel Borkmann a0fb05d1ae net: sctp: fix bug in sctp_poll for SOCK_SELECT_ERR_QUEUE
If we do not add braces around ...

  mask |= POLLERR |
          sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0;

... then this condition always evaluates to true as POLLERR is
defined as 8 and binary or'd with whatever result comes out of
sock_flag(). Hence instead of (X | Y) ? A : B, transform it into
X | (Y ? A : B). Unfortunatelty, commit 8facd5fb73 ("net: fix
smatch warnings inside datagram_poll") forgot about SCTP. :-(

Introduced by 7d4c04fc17 ("net: add option to enable error queue
packets waking select").

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-11 16:09:59 -04:00
Alexander Sverdlin c08751c851 net: sctp: Fix data chunk fragmentation for MTU values which are not multiple of 4
net: sctp: Fix data chunk fragmentation for MTU values which are not multiple of 4

Initially the problem was observed with ipsec, but later it became clear that
SCTP data chunk fragmentation algorithm has problems with MTU values which are
not multiple of 4. Test program was used which just transmits 2000 bytes long
packets to other host. tcpdump was used to observe re-fragmentation in IP layer
after SCTP already fragmented data chunks.

With MTU 1500:
12:54:34.082904 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 1500)
    10.151.38.153.39303 > 10.151.24.91.54321: sctp (1) [DATA] (B) [TSN: 2366088589] [SID: 0] [SSEQ 1] [PPID 0x0]
12:54:34.082933 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 596)
    10.151.38.153.39303 > 10.151.24.91.54321: sctp (1) [DATA] (E) [TSN: 2366088590] [SID: 0] [SSEQ 1] [PPID 0x0]
12:54:34.090576 IP (tos 0x2,ECT(0), ttl 63, id 0, offset 0, flags [DF], proto SCTP (132), length 48)
    10.151.24.91.54321 > 10.151.38.153.39303: sctp (1) [SACK] [cum ack 2366088590] [a_rwnd 79920] [#gap acks 0] [#dup tsns 0]

With MTU 1499:
13:02:49.955220 IP (tos 0x2,ECT(0), ttl 64, id 48215, offset 0, flags [+], proto SCTP (132), length 1492)
    10.151.38.153.39084 > 10.151.24.91.54321: sctp[|sctp]
13:02:49.955249 IP (tos 0x2,ECT(0), ttl 64, id 48215, offset 1472, flags [none], proto SCTP (132), length 28)
    10.151.38.153 > 10.151.24.91: ip-proto-132
13:02:49.955262 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 600)
    10.151.38.153.39084 > 10.151.24.91.54321: sctp (1) [DATA] (E) [TSN: 404355346] [SID: 0] [SSEQ 1] [PPID 0x0]
13:02:49.956770 IP (tos 0x2,ECT(0), ttl 63, id 0, offset 0, flags [DF], proto SCTP (132), length 48)
    10.151.24.91.54321 > 10.151.38.153.39084: sctp (1) [SACK] [cum ack 404355346] [a_rwnd 79920] [#gap acks 0] [#dup tsns 0]

Here problem in data portion limit calculation leads to re-fragmentation in IP,
which is sub-optimal. The problem is max_data initial value, which doesn't take
into account the fact, that data chunk must be padded to 4-bytes boundary.
It's enough to correct max_data, because all later adjustments are correctly
aligned to 4-bytes boundary.

After the fix is applied, everything is fragmented correctly for uneven MTUs:
15:16:27.083881 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 1496)
    10.151.38.153.53417 > 10.151.24.91.54321: sctp (1) [DATA] (B) [TSN: 3077098183] [SID: 0] [SSEQ 1] [PPID 0x0]
15:16:27.083907 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 600)
    10.151.38.153.53417 > 10.151.24.91.54321: sctp (1) [DATA] (E) [TSN: 3077098184] [SID: 0] [SSEQ 1] [PPID 0x0]
15:16:27.085640 IP (tos 0x2,ECT(0), ttl 63, id 0, offset 0, flags [DF], proto SCTP (132), length 48)
    10.151.24.91.54321 > 10.151.38.153.53417: sctp (1) [SACK] [cum ack 3077098184] [a_rwnd 79920] [#gap acks 0] [#dup tsns 0]

The bug was there for years already, but
 - is a performance issue, the packets are still transmitted
 - doesn't show up with default MTU 1500, but possibly with ipsec (MTU 1438)

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04 13:20:27 -04:00
Daniel Borkmann b1b72076b9 net: sctp: probe: allow more advanced ingress filtering by mark
This is a follow-up commit for commit b1dcdc68b1 ("net: tcp_probe:
allow more advanced ingress filtering by mark") that allows for
advanced SCTP probe module filtering based on skb mark (for a more
detailed description and advantages using mark, refer to b1dcdc68b1).
The current option to filter by a given port is still being preserved.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03 21:44:11 -04:00
Daniel Borkmann 7613f5fe11 net: sctp: sctp_verify_init: clean up mandatory checks and add comment
Add a comment related to RFC4960 explaning why we do not check for initial
TSN, and while at it, remove yoda notation checks and clean up code from
checks of mandatory conditions. That's probably just really minor, but makes
reviewing easier.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-29 15:54:48 -04:00
Daniel Borkmann 05f147ef7c net: sctp_probe: simplify code by using %pISc format specifier
We can simply use the %pISc format specifier that was recently added
and thus remove some code that distinguishes between IPv4 and IPv6.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-22 22:07:06 -07:00
David S. Miller 2ff1cf12c9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-08-16 15:37:26 -07:00
Francesco Fusco d14c5ab6be net: proc_fs: trivial: print UIDs as unsigned int
UIDs are printed in the proc_fs as signed int, whereas
they are unsigned int.

Signed-off-by: Francesco Fusco <ffusco@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-15 14:37:46 -07:00
Vlad Yasevich 072017b41e net: sctp: Add rudimentary infrastructure to account for control chunks
This patch adds a base infrastructure that allows SCTP to do
memory accounting for control chunks.  Real accounting code will
follow.

This patch alos fixes the following triggered bug ...

[  553.109742] kernel BUG at include/linux/skbuff.h:1813!
[  553.109766] invalid opcode: 0000 [#1] SMP
[  553.109789] Modules linked in: sctp libcrc32c rfcomm [...]
[  553.110259]  uinput i915 i2c_algo_bit drm_kms_helper e1000e drm ptp
pps_core i2c_core wmi video sunrpc
[  553.110320] CPU: 0 PID: 1636 Comm: lt-test_1_to_1_ Not tainted
3.11.0-rc3+ #2
[  553.110350] Hardware name: LENOVO 74597D6/74597D6, BIOS 6DET60WW
(3.10 ) 09/17/2009
[  553.110381] task: ffff88020a01dd40 ti: ffff880204ed0000 task.ti:
ffff880204ed0000
[  553.110411] RIP: 0010:[<ffffffffa0698017>]  [<ffffffffa0698017>]
skb_orphan.part.9+0x4/0x6 [sctp]
[  553.110459] RSP: 0018:ffff880204ed1bb8  EFLAGS: 00010286
[  553.110483] RAX: ffff8802086f5a40 RBX: ffff880204303300 RCX:
0000000000000000
[  553.110487] RDX: ffff880204303c28 RSI: ffff8802086f5a40 RDI:
ffff880202158000
[  553.110487] RBP: ffff880204ed1bb8 R08: 0000000000000000 R09:
0000000000000000
[  553.110487] R10: ffff88022f2d9a04 R11: ffff880233001600 R12:
0000000000000000
[  553.110487] R13: ffff880204303c00 R14: ffff8802293d0000 R15:
ffff880202158000
[  553.110487] FS:  00007f31b31fe740(0000) GS:ffff88023bc00000(0000)
knlGS:0000000000000000
[  553.110487] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  553.110487] CR2: 000000379980e3e0 CR3: 000000020d225000 CR4:
00000000000407f0
[  553.110487] Stack:
[  553.110487]  ffff880204ed1ca8 ffffffffa068d7fc 0000000000000000
0000000000000000
[  553.110487]  0000000000000000 ffff8802293d0000 ffff880202158000
ffffffff81cb7900
[  553.110487]  0000000000000000 0000400000001c68 ffff8802086f5a40
000000000000000f
[  553.110487] Call Trace:
[  553.110487]  [<ffffffffa068d7fc>] sctp_sendmsg+0x6bc/0xc80 [sctp]
[  553.110487]  [<ffffffff8128f185>] ? sock_has_perm+0x75/0x90
[  553.110487]  [<ffffffff815a3593>] inet_sendmsg+0x63/0xb0
[  553.110487]  [<ffffffff8128f2b3>] ? selinux_socket_sendmsg+0x23/0x30
[  553.110487]  [<ffffffff8151c5d6>] sock_sendmsg+0xa6/0xd0
[  553.110487]  [<ffffffff81637b05>] ? _raw_spin_unlock_bh+0x15/0x20
[  553.110487]  [<ffffffff8151cd38>] SYSC_sendto+0x128/0x180
[  553.110487]  [<ffffffff8151ce6b>] ? SYSC_connect+0xdb/0x100
[  553.110487]  [<ffffffffa0690031>] ? sctp_inet_listen+0x71/0x1f0
[sctp]
[  553.110487]  [<ffffffff8151d35e>] SyS_sendto+0xe/0x10
[  553.110487]  [<ffffffff81640202>] system_call_fastpath+0x16/0x1b
[  553.110487] Code: e0 48 c7 c7 00 22 6a a0 e8 67 a3 f0 e0 48 c7 [...]
[  553.110487] RIP  [<ffffffffa0698017>] skb_orphan.part.9+0x4/0x6
[sctp]
[  553.110487]  RSP <ffff880204ed1bb8>
[  553.121578] ---[ end trace 46c20c5903ef5be2 ]---

The approach taken here is to split data and control chunks
creation a  bit.  Data chunks already have memory accounting
so noting needs to happen.  For control chunks, add stubs handlers.

Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-13 15:04:02 -07:00
Daniel Borkmann 771085d6bf net: sctp: sctp_transport_destroy{, _rcu}: fix potential pointer corruption
Probably this one is quite unlikely to be triggered, but it's more safe
to do the call_rcu() at the end after we have dropped the reference on
the asoc and freed sctp packet chunks. The reason why is because in
sctp_transport_destroy_rcu() the transport is being kfree()'d, and if
we're unlucky enough we could run into corrupted pointers. Probably
that's more of theoretical nature, but it's safer to have this simple fix.

Introduced by commit 8c98653f ("sctp: sctp_close: fix release of bindings
for deferred call_rcu's"). I also did the 8c98653f regression test and
it's fine that way.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-12 22:13:47 -07:00
Daniel Borkmann ac4f959936 net: sctp: sctp_assoc_control_transport: fix MTU size in SCTP_PF state
The SCTP Quick failover draft [1] section 5.1, point 5 says that the cwnd
should be 1 MTU. So, instead of 1, set it to 1 MTU.

  [1] https://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05

Reported-by: Karl Heiss <kheiss@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-12 22:12:20 -07:00
David S. Miller 71acc0ddd4 Revert "net: sctp: convert sctp_checksum_disable module param into sctp sysctl"
This reverts commit cda5f98e36.

As per Vlad's request.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09 13:09:41 -07:00
Daniel Borkmann 477143e3fe net: sctp: trivial: update bug report in header comment
With the restructuring of the lksctp.org site, we only allow bug
reports through the SCTP mailing list linux-sctp@vger.kernel.org,
not via SF, as SF is only used for web hosting and nothing more.
While at it, also remove the obvious statement that bugs will be
fixed and incooperated into the kernel.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09 11:33:02 -07:00
Daniel Borkmann cda5f98e36 net: sctp: convert sctp_checksum_disable module param into sctp sysctl
Get rid of the last module parameter for SCTP and make this
configurable via sysctl for SCTP like all the rest of SCTP's
configuration knobs.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09 11:33:02 -07:00
fan.du d27fc78208 sctp: Don't lookup dst if transport dst is still valid
When sctp sits on IPv6, sctp_transport_dst_check pass cookie as ZERO,
as a result ip6_dst_check always fail out. This behaviour makes
transport->dst useless, because every sctp_packet_transmit must look
for valid dst.

Add a dst_cookie into sctp_transport, and set the cookie whenever we
get new dst for sctp_transport. So dst validness could be checked
against it.

Since I have split genid for IPv4 and IPv6, also delete/add IPv6 address
will also bump IPv6 genid. So issues we discussed in:
http://marc.info/?l=linux-netdev&m=137404469219410&w=4
have all been sloved for this patch.

Signed-off-by: Fan Du <fan.du@windriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-02 12:36:00 -07:00
Joe Stringer 024ec3deac net/sctp: Refactor SCTP skb checksum computation
This patch consolidates the SCTP checksum calculation code from various
places to a single new function, sctp_compute_cksum(skb, offset).

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-27 20:07:15 -07:00
Daniel Borkmann 91705c61b5 net: sctp: trivial: update mailing list address
The SCTP mailing list address to send patches or questions
to is linux-sctp@vger.kernel.org and not
lksctp-developers@lists.sourceforge.net anymore. Therefore,
update all occurences.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-24 17:53:38 -07:00
Daniel Borkmann 8c2f414ad1 net: sctp: confirm route during forward progress
This fix has been proposed originally by Vlad Yasevich. He says:

  When SCTP makes forward progress (receives a SACK that acks new chunks,
  renegs, or answeres 0-window probes) or when HB-ACK arrives, mark
  the route as confirmed so we don't unnecessarily send NUD probes.

Having a simple SCTP client/server that exchange data chunks every 1sec,
without this patch ARP requests are sent periodically every 40-60sec.
With this fix applied, an ARP request is only done once right at the
"session" beginning. Also, when clearing the related ARP cache entry
manually during the session, a new request is correctly done. I have
only "backported" this to net-next and tested that it works, so full
credit goes to Vlad.

Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-09 12:49:56 -07:00
Yann Droneaud 8a59bd3e9b sctp: use get_unused_fd_flags(0) instead of get_unused_fd()
Macro get_unused_fd() is used to allocate a file descriptor with
default flags. Those default flags (0) can be "unsafe":
O_CLOEXEC must be used by default to not leak file descriptor
across exec().

Instead of macro get_unused_fd(), functions anon_inode_getfd()
or get_unused_fd_flags() should be used with flags given by userspace.
If not possible, flags should be set to O_CLOEXEC to provide userspace
with a default safe behavor.

In a further patch, get_unused_fd() will be removed so that
new code start using anon_inode_getfd() or get_unused_fd_flags()
with correct flags.

This patch replaces calls to get_unused_fd() with equivalent call to
get_unused_fd_flags(0) to preserve current behavor for existing code.

The hard coded flag value (0) should be reviewed on a per-subsystem basis,
and, if possible, set to O_CLOEXEC.

Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-02 16:14:11 -07:00
Daniel Borkmann e02010adee net: sctp: get rid of SCTP_DBG_TSNS entirely
After having reworked the debugging framework, Neil and Vlad agreed to
get rid of the leftover SCTP_DBG_TSNS code for a couple of reasons:

We can use systemtap scripts to investigate these things, we now have
pr_debug() helpers that make life easier, and if we really need anything
else besides those tools, we will be forced to come up with something
better than we have there. Therefore, get rid of this ifdef debugging
code entirely for now.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-02 00:08:03 -07:00
Daniel Borkmann bb33381d0c net: sctp: rework debugging framework to use pr_debug and friends
We should get rid of all own SCTP debug printk macros and use the ones
that the kernel offers anyway instead. This makes the code more readable
and conform to the kernel code, and offers all the features of dynamic
debbuging that pr_debug() et al has, such as only turning on/off portions
of debug messages at runtime through debugfs. The runtime cost of having
CONFIG_DYNAMIC_DEBUG enabled, but none of the debug statements printing,
is negligible [1]. If kernel debugging is completly turned off, then these
statements will also compile into "empty" functions.

While we're at it, we also need to change the Kconfig option as it /now/
only refers to the ifdef'ed code portions in outqueue.c that enable further
debugging/tracing of SCTP transaction fields. Also, since SCTP_ASSERT code
was enabled with this Kconfig option and has now been removed, we
transform those code parts into WARNs resp. where appropriate BUG_ONs so
that those bugs can be more easily detected as probably not many people
have SCTP debugging permanently turned on.

To turn on all SCTP debugging, the following steps are needed:

 # mount -t debugfs none /sys/kernel/debug
 # echo -n 'module sctp +p' > /sys/kernel/debug/dynamic_debug/control

This can be done more fine-grained on a per file, per line basis and others
as described in [2].

 [1] https://www.kernel.org/doc/ols/2009/ols2009-pages-39-46.pdf
 [2] Documentation/dynamic-debug-howto.txt

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-01 23:22:13 -07:00
Daniel Borkmann 62208f1245 net: sctp: simplify sctp_get_port
No need to have an extra ret variable when we directly can return
the value of sctp_get_port_local().

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-25 16:33:05 -07:00
Daniel Borkmann 0a2fbac197 net: sctp: decouple cleaning some socket data from endpoint
Rather instead of having the endpoint clean the garbage from the
socket, use a sk_destruct handler sctp_destruct_sock(), that does
the job for that when there are no more references on the socket.
At least do this for our crypto transform through crypto_free_hash()
that is allocated when in listening state.

Also, perform sctp_put_port() only when sk is valid. At a later
point in time we can still determine if there's an option of
placing this into sk_prot->unhash() or sctp_endpoint_free() without
any races. For now, leave it in sctp_endpoint_destroy() though.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-25 16:33:04 -07:00
Daniel Borkmann b527fe6933 net: sctp: minor: sctp_seq_dump_local_addrs add missing newline
A trailing newline has been forgotten to add into the WARN().

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-25 16:33:04 -07:00
Daniel Borkmann 52db882f3f net: sctp: migrate cookie life from timeval to ktime
Currently, SCTP code defines its own timeval functions (since timeval
is rarely used inside the kernel by others), namely tv_lt() and
TIMEVAL_ADD() macros, that operate on SCTP cookie expiration.

We might as well remove all those, and operate directly on ktime
structures for a couple of reasons: ktime is available on all archs;
complexity of ktime calculations depending on the arch is less than
(reduces to a simple arithmetic operations on archs with
BITS_PER_LONG == 64 or CONFIG_KTIME_SCALAR) or equal to timeval
functions (other archs); code becomes more readable; macros can be
thrown out.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-25 16:33:04 -07:00
Dave Jones 2c0740e4e1 sctp: Convert __list_for_each use to list_for_each
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-19 23:02:49 -07:00
David S. Miller d98cae64e4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/wireless/ath/ath9k/Kconfig
	drivers/net/xen-netback/netback.c
	net/batman-adv/bat_iv_ogm.c
	net/wireless/nl80211.c

The ath9k Kconfig conflict was a change of a Kconfig option name right
next to the deletion of another option.

The xen-netback conflict was overlapping changes involving the
handling of the notify list in xen_netbk_rx_action().

Batman conflict resolution provided by Antonio Quartulli, basically
keep everything in both conflict hunks.

The nl80211 conflict is a little more involved.  In 'net' we added a
dynamic memory allocation to nl80211_dump_wiphy() to fix a race that
Linus reported.  Meanwhile in 'net-next' the handlers were converted
to use pre and post doit handlers which use a flag to determine
whether to hold the RTNL mutex around the operation.

However, the dump handlers to not use this logic.  Instead they have
to explicitly do the locking.  There were apparent bugs in the
conversion of nl80211_dump_wiphy() in that we were not dropping the
RTNL mutex in all the return paths, and it seems we very much should
be doing so.  So I fixed that whilst handling the overlapping changes.

To simplify the initial returns, I take the RTNL mutex after we try
to allocate 'tb'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-19 16:49:39 -07:00
Daniel Borkmann dda9192851 net: sctp: remove SCTP_STATIC macro
SCTP_STATIC is just another define for the static keyword. It's use
is inconsistent in the SCTP code anyway and it was introduced in the
initial implementation of SCTP in 2.5. We have a regression suite in
lksctp-tools, but this is for user space only, so noone makes use of
this macro anymore. The kernel test suite for 2.5 is incompatible with
the current SCTP code anyway.

So simply Remove it, to be more consistent with the rest of the kernel
code.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 17:08:05 -07:00