Commit Graph

584 Commits

Author SHA1 Message Date
Gerrit Renker
48816322ad dccp: Empty the write queue when disconnecting
dccp_disconnect() can be called due to several reasons:

 1. when the connection setup failed (inet_stream_connect());
 2. when shutting down (inet_shutdown(), inet_csk_listen_stop());
 3. when aborting the connection (dccp_close() with 0 linger time).

In case (1) the write queue is empty. This patch empties the write queue,
if in case (2) or (3) it was not yet empty.

This avoids triggering the write-queue BUG_TRAP in sk_stream_kill_queues()
later on.

It also seems natural to do: when breaking an association, to delete all
packets that were originally intended for the soon-disconnected end (compare
with call to tcp_write_queue_purge in tcp_disconnect()).

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04 07:45:25 +02:00
Gerrit Renker
eac7726bf5 dccp: Fill in the Data fields for "Option Error" Resets
This updates the use of the `out_invalid_option' label, which produces a 
Reset (code 5, "Option Error"), to fill in the  Data1...Data3 fields as
specified in RFC 4340, 5.6.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04 07:45:25 +02:00
Gerrit Renker
faf61c3319 dccp: Silently ignore options with nonsensical lengths
This updates the option-parsing code with regard to RFC 4340, 5.8:
 "[..] options with nonsensical lengths (length byte less than two or more
  than the remaining space in the options portion of the header) MUST be
  ignored, and any option space following an option with nonsensical length
  MUST likewise be ignored."

Hence in the following cases erratic options will be ignored:
 1. The type byte of a multi-byte option is the last byte of the header
    options (i.e. effective option length of 1).
 2. The value of the length byte is less than the minimum 2. This has been 
    changed from previously 3: although no multi-byte option with a length
    less than 3 yet exists (cf. table 3 in 5.8), a length of 2 is valid.
    (The switch-statement in dccp_parse has further per-option length checks.)
 3. The option length exceeds the length of the remaining option space.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04 07:45:24 +02:00
Wei Yongjun
ba1a6c7bc0 dccp: Always generate a Reset in response to option errors
RFC4340 states that if a packet is received with an option error (such as a
Mandatory Option as the last byte of the option list), the endpoint should
repond with a Reset.

In the LISTEN and RESPOND states, the endpoint correctly reponds with Reset,
while in the REQUEST/OPEN states, packets with option errors are just ignored.

The packet sequence is as follows:

Case 1:

  Endpoint A                           Endpoint B
  (CLOSED)                             (CLOSED)

               <----------------       REQUEST

  RESPONSE     ----------------->      (*1)
  (with invalid option)
               <----------------       RESET
                                       (with Reset Code 5, "Option Error")

  (*1) currently just ignored, no Reset is sent

Case 2:

  Endpoint A                           Endpoint B
  (OPEN)                               (OPEN)

  DATA-ACK     ----------------->      (*2)
  (with invalid option)
               <----------------       RESET
                                       (with Reset Code 5, "Option Error")

  (*2) currently just ignored, no Reset is sent

This patch fixes the problem, by generating a Reset instead of silently
ignoring option errors.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-09-04 07:45:24 +02:00
Gerrit Renker
d28934ad8a dccp: Fix panic caused by too early termination of retransmission mechanism
Thanks is due to Wei Yongjun for the detailed analysis and description of this
bug at http://marc.info/?l=dccp&m=121739364909199&w=2

The problem is that invalid packets received by a client in state REQUEST cause
the retransmission timer for the DCCP-Request to be reset. This includes freeing
the Request-skb ( in dccp_rcv_request_sent_state_process() ). As a consequence,
 * the arrival of further packets cause a double-free, triggering a panic(),
 * the connection then may hang, since further retransmissions are blocked.

This patch changes the order of statements so that the retransmission timer is
reset, and the pending Request freed, only if a valid Response has arrived (or
the number of sysctl-retries has been exhausted).

Further changes:
----------------
To be on the safe side, replaced __kfree_skb with kfree_skb so that if due to
unexpected circumstances the sk_send_head is NULL the WARN_ON is used instead.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-18 21:14:20 -07:00
Arnaldo Carvalho de Melo
3e8a0a559c dccp: change L/R must have at least one byte in the dccpsf_val field
Thanks to Eugene Teo for reporting this problem.
    
Signed-off-by: Eugene Teo <eugenete@kernel.sg>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-13 13:48:39 -07:00
Gui Jianfeng
6edafaaf6f tcp: Fix kernel panic when calling tcp_v(4/6)_md5_do_lookup
If the following packet flow happen, kernel will panic.
MathineA			MathineB
		SYN
	---------------------->    
        	SYN+ACK
	<----------------------
		ACK(bad seq)
	---------------------->
When a bad seq ACK is received, tcp_v4_md5_do_lookup(skb->sk, ip_hdr(skb)->daddr))
is finally called by tcp_v4_reqsk_send_ack(), but the first parameter(skb->sk) is 
NULL at that moment, so kernel panic happens.
This patch fixes this bug.

OOPS output is as following:
[  302.812793] IP: [<c05cfaa6>] tcp_v4_md5_do_lookup+0x12/0x42
[  302.817075] Oops: 0000 [#1] SMP 
[  302.819815] Modules linked in: ipv6 loop dm_multipath rtc_cmos rtc_core rtc_lib pcspkr pcnet32 mii i2c_piix4 parport_pc i2c_core parport ac button ata_piix libata dm_mod mptspi mptscsih mptbase scsi_transport_spi sd_mod scsi_mod crc_t10dif ext3 jbd mbcache uhci_hcd ohci_hcd ehci_hcd [last unloaded: scsi_wait_scan]
[  302.849946] 
[  302.851198] Pid: 0, comm: swapper Not tainted (2.6.27-rc1-guijf #5)
[  302.855184] EIP: 0060:[<c05cfaa6>] EFLAGS: 00010296 CPU: 0
[  302.858296] EIP is at tcp_v4_md5_do_lookup+0x12/0x42
[  302.861027] EAX: 0000001e EBX: 00000000 ECX: 00000046 EDX: 00000046
[  302.864867] ESI: ceb69e00 EDI: 1467a8c0 EBP: cf75f180 ESP: c0792e54
[  302.868333]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[  302.871287] Process swapper (pid: 0, ti=c0792000 task=c0712340 task.ti=c0746000)
[  302.875592] Stack: c06f413a 00000000 cf75f180 ceb69e00 00000000 c05d0d86 000016d0 ceac5400 
[  302.883275]        c05d28f8 000016d0 ceb69e00 ceb69e20 681bf6e3 00001000 00000000 0a67a8c0 
[  302.890971]        ceac5400 c04250a3 c06f413a c0792eb0 c0792edc cf59a620 cf59a620 cf59a634 
[  302.900140] Call Trace:
[  302.902392]  [<c05d0d86>] tcp_v4_reqsk_send_ack+0x17/0x35
[  302.907060]  [<c05d28f8>] tcp_check_req+0x156/0x372
[  302.910082]  [<c04250a3>] printk+0x14/0x18
[  302.912868]  [<c05d0aa1>] tcp_v4_do_rcv+0x1d3/0x2bf
[  302.917423]  [<c05d26be>] tcp_v4_rcv+0x563/0x5b9
[  302.920453]  [<c05bb20f>] ip_local_deliver_finish+0xe8/0x183
[  302.923865]  [<c05bb10a>] ip_rcv_finish+0x286/0x2a3
[  302.928569]  [<c059e438>] dev_alloc_skb+0x11/0x25
[  302.931563]  [<c05a211f>] netif_receive_skb+0x2d6/0x33a
[  302.934914]  [<d0917941>] pcnet32_poll+0x333/0x680 [pcnet32]
[  302.938735]  [<c05a3b48>] net_rx_action+0x5c/0xfe
[  302.941792]  [<c042856b>] __do_softirq+0x5d/0xc1
[  302.944788]  [<c042850e>] __do_softirq+0x0/0xc1
[  302.948999]  [<c040564b>] do_softirq+0x55/0x88
[  302.951870]  [<c04501b1>] handle_fasteoi_irq+0x0/0xa4
[  302.954986]  [<c04284da>] irq_exit+0x35/0x69
[  302.959081]  [<c0405717>] do_IRQ+0x99/0xae
[  302.961896]  [<c040422b>] common_interrupt+0x23/0x28
[  302.966279]  [<c040819d>] default_idle+0x2a/0x3d
[  302.969212]  [<c0402552>] cpu_idle+0xb2/0xd2
[  302.972169]  =======================
[  302.974274] Code: fc ff 84 d2 0f 84 df fd ff ff e9 34 fe ff ff 83 c4 0c 5b 5e 5f 5d c3 90 90 57 89 d7 56 53 89 c3 50 68 3a 41 6f c0 e8 e9 55 e5 ff <8b> 93 9c 04 00 00 58 85 d2 59 74 1e 8b 72 10 31 db 31 c9 85 f6 
[  303.011610] EIP: [<c05cfaa6>] tcp_v4_md5_do_lookup+0x12/0x42 SS:ESP 0068:c0792e54
[  303.018360] Kernel panic - not syncing: Fatal exception in interrupt

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-06 23:50:04 -07:00
Wei Yongjun
860239c56b dccp: Add check for truncated ICMPv6 DCCP error packets
This patch adds a minimum-length check for ICMPv6 packets, as per the previous
patch for ICMPv4 payloads.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-26 11:59:11 +01:00
Wei Yongjun
18e1d83600 dccp: Fix incorrect length check for ICMPv4 packets
Unlike TCP, which only needs 8 octets of original packet data, DCCP requires
minimally 12 or 16 bytes for ICMP-payload sequence number checks.

This patch replaces the insufficient length constant of 8 with a two-stage
test, making sure that 12 bytes are available, before computing the basic
header length required for sequence number checks.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-26 11:59:10 +01:00
Wei Yongjun
e0bcfb0c6a dccp: Add check for sequence number in ICMPv6 message
This adds a sequence number check for ICMPv6 DCCP error packets, in the same
manner as it has been done for ICMPv4 in the previous patch.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-26 11:59:10 +01:00
Wei Yongjun
d68f0866f7 dccp: Fix sequence number check for ICMPv4 packets
The payload of ICMP message is a part of the packet sent by ourself,
so the sequence number check must use AWL and AWH, not SWL and SWH.

For example:
     Endpoint A                  Endpoint B

     DATA-ACK       -------->
     (SEQ=X)
                    <--------    ICMP (Fragmentation Needed)
                                 (SEQ=X)

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-26 11:59:10 +01:00
Gerrit Renker
73f18fdbca dccp: Bug-Fix - AWL was never updated
The AWL lower Ack validity window advances in proportion to GSS, the greatest
sequence number sent. Updating AWL other than at connection setup (in the
DCCP-Request sent by dccp_v{4,6}_connect()) was missing in the DCCP code.

This bug lead to syslog messages such as

 "kernel: dccp_check_seqno: DCCP: Step 6 failed for DATAACK packet, [...] 
  P.ackno exists or LAWL(82947089) <= P.ackno(82948208)
                                   <= S.AWH(82948728), sending SYNC..."

The difference between AWL/AWH here is 1639 packets, while the expected value
(the Sequence Window) would have been 100 (the default).  A closer look showed
that LAWL = AWL = 82947089 equalled the ISS on the Response.

The patch now updates AWL with each increase of GSS.


Further changes:
----------------
The patch also enforces more stringent checks on the ISS sequence number:

 * AWL is initialised to ISS at connection setup and remains at this value;
 * AWH is then always set to GSS (via dccp_update_gss());
 * so on the first Request: AWL =      AWH = ISS,
   and on the n-th Request: AWL = ISS, AWH = ISS + n.

As a consequence, only Response packets that refer to Requests sent by this
host will pass, all others are discarded. This is the intention and in effect 
implements the initial adjustments for AWL as specified in RFC 4340, 7.5.1.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>   
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-07-26 11:59:10 +01:00
Gerrit Renker
59435444a1 dccp: Allow to distinguish original and retransmitted packets
This patch allows the sender to distinguish original and retransmitted packets,
which is in particular needed for the retransmission of DCCP-Requests:
 * the first Request uses ISS (generated in net/dccp/ip*.c), and sets GSS = ISS;
 * all retransmitted Requests use GSS' = GSS + 1, so that the n-th retransmitted
   Request has sequence number ISS + n (mod 48).

To add generic support, the patch reorganises existing code so that:
 * icsk_retransmits == 0     for the original packet and
 * icsk_retransmits = n > 0  for the n-th retransmitted packet
at the time dccp_transmit_skb() is called, via dccp_retransmit_skb().
 
Thanks to Wei Yongjun for pointing this problem out.

Further changes:
----------------
 * removed the `skb' argument from dccp_retransmit_skb(), since sk_send_head
   is used for all retransmissions (the exception is client-Acks in PARTOPEN
   state, but these do not use sk_send_head);
 * since sk_send_head always contains the original skb (via dccp_entail()),
   skb_cloned() never evaluated to true and thus pskb_copy() was never used.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-26 11:59:09 +01:00
Ilpo Järvinen
547b792cac net: convert BUG_TRAP to generic WARN_ON
Removes legacy reinvent-the-wheel type thing. The generic
machinery integrates much better to automated debugging aids
such as kerneloops.org (and others), and is unambiguous due to
better naming. Non-intuively BUG_TRAP() is actually equal to
WARN_ON() rather than BUG_ON() though some might actually be
promoted to BUG_ON() but I left that to future.

I could make at least one BUILD_BUG_ON conversion.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-25 21:43:18 -07:00
Pavel Emelyanov
de0744af1f mib: add net to NET_INC_STATS_BH
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16 20:31:16 -07:00
Pavel Emelyanov
ca12a1a443 inet: prepare net on the stack for NET accounting macros
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16 20:28:42 -07:00
Pavel Emelyanov
7c73a6faff mib: add net to IP_INC_STATS_BH
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16 20:20:11 -07:00
Pavel Emelyanov
dcfc23cac1 mib: add struct net to ICMP_INC_STATS_BH
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-14 23:05:29 -07:00
Pavel Emelyanov
fd54d716b1 inet: toss struct net initialization around
Some places, that deal with ICMP statistics already have where
to get a struct net from, but use it directly, without declaring
a separate variable on the stack.

Since I will need this net soon, I declare a struct net on the
stack and use it in the existing places in a separate patch not
to spoil the future ones.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-14 23:05:26 -07:00
Gerrit Renker
2eeea7ba6b dccp ccid-3: Length of loss intervals
This corrects an error in the computation of the open loss interval I_0:
  * the interval length is (highest_seqno - start_seqno) + 1
  * and not (highest_seqno - start_seqno).

This condition was not fully clear in RFC 3448, but reflects the current
revision state of rfc3448bis and is also consistent with RFC 4340, 6.1.1.

Further changes:
----------------
 * variable renamed due to line length constraints;
 * explicit typecast to `s64' to avoid implicit signed/unsigned casting.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-13 11:51:40 +01:00
Gerrit Renker
b552c6231f dccp ccid-3: Fix a loss detection bug
This fixes a bug in the logic of the TFRC loss detection:
 * new_loss_indicated() should not be called while a loss is pending;
 * but the code allows this;
 * thus, for two subsequent gaps in the sequence space, when loss_count
   has not yet reached NDUPACK=3, the loss_count is falsely reduced to 1.

To avoid further and similar problems, all loss handling and loss detection is
now done inside tfrc_rx_hist_handle_loss(), using an appropriate routine to
track new losses.

Further changes:
----------------
 * added a reminder that no RX history operations should be performed when
   rx_handle_loss() has identified a (new) loss, since the function takes
   care of packet reordering during loss detection;
 * made tfrc_rx_hist_loss_pending() bool (thanks to an earlier suggestion
   by Arnaldo);		 
 * removed unused functions.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-13 11:51:40 +01:00
Gerrit Renker
5b5d0e7048 dccp: Upgrade NDP count from 3 to 6 bytes
RFC 4340, 7.7 specifies up to 6 bytes for the NDP Count option, whereas the code
is currently limited to up to 3 bytes. This seems to be a relict of an earlier 
draft version and is brought up to date by the patch.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-13 11:51:40 +01:00
Gerrit Renker
2013c7e35a dccp ccid-3: Fix error in loss detection
The TFRC loss detection code used the wrong loss condition (RFC 4340, 7.7.1):
 * the difference between sequence numbers s1 and s2 instead of 
 * the number of packets missing between s1 and s2 (one less than the distance).

Since this condition appears in many places of the code, it has been put into a
separate function, dccp_loss_free().

Further changes:
----------------
 * tidied up incorrect typing (it was using `int' for u64/s64 types);
 * optimised conditional statements for common case of non-reordered packets;
 * rewrote comments/documentation to match the changes.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-13 11:51:40 +01:00
Brian Haley
7d06b2e053 net: change proto destroy method to return void
Change struct proto destroy function pointer to return void.  Noticed
by Al Viro.

Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-14 17:04:49 -07:00
Gerrit Renker
be4c798a41 dccp: Bug in initial acknowledgment number assignment
Step 8.5 in RFC 4340 says for the newly cloned socket

           Initialize S.GAR := S.ISS,

but what in fact the code (minisocks.c) does is

           Initialize S.GAR := S.ISR,

which is wrong (typo?) -- fixed by the patch.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-06-11 11:19:10 +01:00
Gerrit Renker
7deb0f8510 dccp ccid-3: X truncated due to type conversion
This fixes a bug in computing the inter-packet-interval t_ipi = s/X: 

 scaled_div32(a, b) uses u32 for b, but in "scaled_div32(s, X)" the type of the
 sending rate `X' is u64. Since X is scaled by 2^6, this truncates rates greater
 than 2^26 Bps (~537 Mbps).

Using full 64-bit division now.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-06-11 11:19:10 +01:00
Gerrit Renker
1e8a287c79 dccp ccid-3: TFRC reverse-lookup Bug-Fix
This fixes a bug in the reverse lookup of p: given a value f(p), instead of p,
the function returned the smallest tabulated value f(p).

The smallest tabulated value of
	 
   10^6 * f(p) =  sqrt(2*p/3) + 12 * sqrt(3*p/8) * (32 * p^3 + p) 

for p=0.0001 is 8172. 

Since this value is scaled by 10^6, the outcome of this bug is that a loss
of 8172/10^6 = 0.8172% was reported whenever the input was below the table
resolution of 0.01%.

This means that the value was over 80 times too high, resulting in large spikes
of the initial loss interval, thus unnecessarily reducing the throughput.

Also corrected the printk format (%u for u32).

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-06-11 11:19:10 +01:00
Gerrit Renker
65907a433a dccp ccid-2: Bug-Fix - Ack Vectors need to be ignored on request sockets
This fixes an oversight from an earlier patch, ensuring that Ack Vectors
are not processed on request sockets.

The issue is that Ack Vectors must not be parsed on request sockets, since
the Ack Vector feature depends on the selection of the (TX) CCID. During the
initial handshake the CCIDs are undefined, and so RFC 4340, 10.3 applies:

 "Using CCID-specific options and feature options during a negotiation
  for the corresponding CCID feature is NOT RECOMMENDED [...]"

And it is not even possible: when the server receives the Request from the 
client, the CCID and Ack vector features are undefined; when the Ack finalising
the 3-way hanshake arrives, the request socket has not been cloned yet into a
full socket. (This order is necessary, since otherwise the newly created socket
would have to be destroyed whenever an option error occurred - a malicious
hacker could simply send garbage options and exploit this.)

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-06-11 11:19:09 +01:00
Gerrit Renker
1e2f0e5e83 dccp: Fix sparse warnings
This patch fixes the following sparse warnings:
 * nested min(max()) expression:
   net/dccp/ccids/ccid3.c:91:21: warning: symbol '__x' shadows an earlier one
   net/dccp/ccids/ccid3.c:91:21: warning: symbol '__y' shadows an earlier one
   
 * Declaration of function prototypes in .c instead of .h file, resulting in
   "should it be static?" warnings. 

 * Declared "struct dccpw" static (local to dccp_probe).
 
 * Disabled dccp_delayed_ack() - not fully removed due to RFC 4340, 11.3
   ("Receivers SHOULD implement delayed acknowledgement timers ...").

 * Used a different local variable name to avoid
   net/dccp/ackvec.c:293:13: warning: symbol 'state' shadows an earlier one
   net/dccp/ackvec.c:238:33: originally declared here

 * Removed unused functions `dccp_ackvector_print' and `dccp_ackvec_print'.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-06-11 11:19:09 +01:00
Gerrit Renker
3294f202dc dccp ccid-3: Bug-Fix - Zero RTT is possible
In commit $(825de27d9e) (from 27th May, commit
message `dccp ccid-3: Fix "t_ipi explosion" bug'), the CCID-3 window counter
computation was fixed to cope with RTTs < 4 microseconds.

Such RTTs can be found e.g. when running CCID-3 over loopback. The fix removed
a check against RTT < 4, but introduced a divide-by-zero bug.

All steady-state RTTs in DCCP are filtered using dccp_sample_rtt(), which
ensures non-zero samples. However, a zero RTT is possible on initialisation,
when there is no RTT sample from the Request/Response exchange.

The fix is to use the fallback-RTT from RFC 4340, 3.4.

This is also better than just fixing update_win_count() since it allows other
parts of the code to always assume that the RTT is non-zero during the time
that the CCID is used.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-06-11 11:19:09 +01:00
Arnaldo Carvalho de Melo
ce4a7d0d48 inet{6}_request_sock: Init ->opt and ->pktopts in the constructor
Wei Yongjun noticed that we may call reqsk_free on request sock objects where
the opt fields may not be initialized, fix it by introducing inet_reqsk_alloc
where we initialize ->opt to NULL and set ->pktopts to NULL in
inet6_reqsk_alloc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-10 12:39:35 -07:00
Gerrit Renker
825de27d9e dccp ccid-3: Fix "t_ipi explosion" bug
The identification of this bug is thanks to Cheng Wei and Tomasz
Grobelny.

To avoid divide-by-zero, the implementation previously ignored RTTs
smaller than 4 microseconds when performing integer division RTT/4.

When the RTT reached a value less than 4 microseconds (as observed on
loopback), this prevented the Window Counter CCVal value from
advancing. As a result, the receiver stopped sending feedback. This in
turn caused non-ending expiries of the nofeedback timer at the sender,
so that the sending rate was progressively reduced until reaching the
minimum of one packet per 64 seconds.

The patch fixes this bug by handling integer division more
intelligently. Due to consistent use of dccp_sample_rtt(),
divide-by-zero-RTT is avoided.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-27 06:33:54 -07:00
Wei Yongjun
6079a463cf dccp: Fix to handle short sequence numbers packet correctly
RFC4340 said:
  8.5.  Pseudocode
       ...
       If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet
             has short sequence numbers), drop packet and return

But DCCP has some mistake to handle short sequence numbers packet, now
it drop packet only if P.type is Data, Ack, or DataAck and P.X == 0.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-27 06:22:38 -07:00
Chris Wright
19443178fb dccp: return -EINVAL on invalid feature length
dccp_feat_change() validates length and on error is returning 1.
This happens to work since call chain is checking for 0 == success,
but this is returned to userspace, so make it a real error value.

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-05 13:50:24 -07:00
Harvey Harrison
84994e16f2 dccp: ccid2.c, ccid3.c use clamp(), clamp_t()
Makes the intention of the nested min/max clear.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-02 16:44:07 -07:00
Linus Torvalds
2e561c7b7e Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (48 commits)
  net: Fix wrong interpretation of some copy_to_user() results.
  xfrm: alg_key_len & alg_icv_len should be unsigned
  [netdrvr] tehuti: move ioctl perm check closer to function start
  ipv6: Fix typo in net/ipv6/Kconfig
  via-velocity: fix vlan receipt
  tg3: sparse cleanup
  forcedeth: realtek phy crossover detection
  ibm_newemac: Increase MDIO timeouts
  gianfar: Fix skb allocation strategy
  netxen: reduce stack usage of netxen_nic_flash_print
  smc911x: test after postfix decrement fails in smc911x_{reset,drop_pkt}
  net drivers: fix platform driver hotplug/coldplug
  forcedeth: new backoff implementation
  ehea: make things static
  phylib: Add support for board-level PHY fixups
  [netdrvr] atlx: code movement: move atl1 parameter parsing
  atlx: remove flash vendor parameter
  korina: misc cleanup
  korina: fix misplaced return statement
  WAN: Fix confusing insmod error code for C101 too.
  ...
2008-04-25 12:28:28 -07:00
Pavel Emelyanov
653252c230 net: Fix wrong interpretation of some copy_to_user() results.
I found some places, that erroneously return the value obtained from
the copy_to_user() call: if some amount of bytes were not able to get
to the user (this is what this one returns) the proper behavior is to
return the -EFAULT error, not that number itself.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-25 01:49:48 -07:00
Linus Torvalds
b0d19a378a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  iwlwifi: Fix built-in compilation of iwlcore
  net: Unexport move_addr_to_{kernel,user}
  rt2x00: Select LEDS_CLASS.
  iwlwifi: Select LEDS_CLASS.
  leds: Do not guard NEW_LEDS with HAS_IOMEM
  [IPSEC]: Fix catch-22 with algorithm IDs above 31
  time: Export set_normalized_timespec.
  tcp: Make use of before macro in tcp_input.c
  hamradio: Remove unneeded and deprecated cli()/sti() calls in dmascc.c
  [NETNS]: Remove empty ->init callback.
  [DCCP]: Convert do_gettimeofday() to getnstimeofday().
  [NETNS]: Don't initialize err variable twice.
  [NETNS]: The ip6_fib_timer can work with garbage on net namespace stop.
  [IPV4]: Convert do_gettimeofday() to getnstimeofday().
  [IPV4]: Make icmp_sk_init() static.
  [IPV6]: Make struct ip6_prohibit_entry_template static.
  tcp: Trivial fix to correct function name in a comment in net/ipv4/tcp.c
  [NET]: Expose netdevice dev_id through sysfs
  skbuff: fix missing kernel-doc notation
  [ROSE]: Fix soft lockup wrt. rose_node_list_lock
2008-04-23 12:23:45 -07:00
YOSHIFUJI Hideaki
cdd04d98f6 [DCCP]: Convert do_gettimeofday() to getnstimeofday().
What do_gettimeofday() does is to call getnstimeofday() and
to convert the result from timespec{} to timeval{}.
We do not always need timeval{} and we can convert timespec{}
when we really need (to print).

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-21 14:28:45 -07:00
Matthew Wilcox
5f090dcb4d net: Remove unnecessary inclusions of asm/semaphore.h
None of these files use any of the functionality promised by
asm/semaphore.h.  It's possible that they rely on it dragging in some
unrelated header file, but I can't build all these files, so we'll have
fix any build failures as they come up.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-04-18 22:15:50 -04:00
Pavel Emelyanov
e56d8b8a2e [INET]: Drop the inet_inherit_port() call.
As I can see from the code, two places (tcp_v6_syn_recv_sock and
dccp_v6_request_recv_sock) that call this one already run with
BHs disabled, so it's safe to call __inet_inherit_port there.

Besides (in case I missed smth with code review) the calltrace
tcp_v6_syn_recv_sock
 `- tcp_v4_syn_recv_sock
     `- __inet_inherit_port
and the similar for DCCP are valid, but assumes BHs to be disabled.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-17 23:17:34 -07:00
Pavel Emelyanov
13f51d82ac [DCCP]: Fix comment about control sockets.
These sockets now have a bit other names and are no longer global.

Shame on me, I haven't provided a good comment for this when
sending DCCP netnsization patches.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-14 02:38:45 -07:00
David S. Miller
df39e8ba56 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	drivers/net/ehea/ehea_main.c
	drivers/net/wireless/iwlwifi/Kconfig
	drivers/net/wireless/rt2x00/rt61pci.c
	net/ipv4/inet_timewait_sock.c
	net/ipv6/raw.c
	net/mac80211/ieee80211_sta.c
2008-04-14 02:30:23 -07:00
Pavel Emelyanov
671a1c7401 [NETNS][DCCPV6]: Make per-net socket lookup.
The inet6_lookup family of functions requires a net to lookup
a socket in, so give a proper one to them.

No more things to do for dccpv6, since routing is OK and the
ipv4-like transport layer filtering is not done for ipv6.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13 22:33:06 -07:00
Pavel Emelyanov
334527d351 [NETNS][DCCPV6]: Actually create ctl socket on each net and use it.
Move the call to inet_ctl_sock_create to init callback (and
inet_ctl_sock_destroy to exit one) and use proper ctl sock
in dccp_v6_ctl_send_reset.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13 22:32:45 -07:00
Pavel Emelyanov
0204774191 [NETNS][DCCPV6]: Move the dccp_v6_ctl_sk on the struct net.
And replace all its usage with init_net's socket.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13 22:32:25 -07:00
Pavel Emelyanov
8231bd270d [NETNS][DCCPV6]: Add dummy per-net operations.
They will be responsible for ctl socket initialization, but
currently they are void.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13 22:32:02 -07:00
Pavel Emelyanov
68d185980f [NETNS][DCCPV6]: Don't pass NULL to ip6_dst_lookup.
This call uses the sock to get the net to lookup the routing
in. With CONFIG_NET_NS this code will OOPS, since the sk ptr
is NULL.

After looking inside the ip6_dst_lookup and drawing the analogy
with respective ipv6 code, it seems, that the dccp ctl socket 
is a good candidate for the first argument.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13 22:31:32 -07:00
Pavel Emelyanov
fc5f8580d3 [NETNS][DCCPV4]: Enable DCCPv4 in net namespaces.
This enables sockets creation with IPPROTO_DCCP and enables
the ip level to pass DCCP packets to the DCCP level.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13 22:31:05 -07:00
Pavel Emelyanov
b9901a84c9 [NETNS][DCCPV4]: Make per-net socket lookup.
The inet_lookup family of functions requires a net to lookup
a socket in, so give a proper one to them.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13 22:30:43 -07:00