Commit Graph

324 Commits

Author SHA1 Message Date
Pavel Emelyanov
ee9952831c tcp: Initial repair mode
This includes (according the the previous description):

* TCP_REPAIR sockoption

This one just puts the socket in/out of the repair mode.
Allowed for CAP_NET_ADMIN and for closed/establised sockets only.
When repair mode is turned off and the socket happens to be in
the established state the window probe is sent to the peer to
'unlock' the connection.

* TCP_REPAIR_QUEUE sockoption

This one sets the queue which we're about to repair. The
'no-queue' is set by default.

* TCP_QUEUE_SEQ socoption

Sets the write_seq/rcv_nxt of a selected repaired queue.
Allowed for TCP_CLOSE-d sockets only. When the socket changes
its state the other seq-s are changed by the kernel according
to the protocol rules (most of the existing code is actually
reused).

* Ability to forcibly bind a socket to a port

The sk->sk_reuse is set to SK_FORCE_REUSE.

* Immediate connect modification

The connect syscall initializes the connection, then directly jumps
to the code which finalizes it.

* Silent close modification

The close just aborts the connection (similar to SO_LINGER with 0
time) but without sending any FIN/RST-s to peer.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-21 15:52:25 -04:00
Linus Torvalds
94fb175c04 dmaengine-fixes for 3.4-rc3
1/ regression fix for Xen as it now trips over a broken assumption
    about the dma address size on 32-bit builds
 
 2/ new quirk for netdma to ignore dma channels that cannot meet
    netdma alignment requirements
 
 3/ fixes for two long standing issues in ioatdma (ring size overflow)
    and iop-adma (potential stack corruption)
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Merge tag 'dmaengine-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine

Pull dmaengine fixes from Dan Williams:

1/ regression fix for Xen as it now trips over a broken assumption
   about the dma address size on 32-bit builds

2/ new quirk for netdma to ignore dma channels that cannot meet
   netdma alignment requirements

3/ fixes for two long standing issues in ioatdma (ring size overflow)
   and iop-adma (potential stack corruption)

* tag 'dmaengine-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
  netdma: adding alignment check for NETDMA ops
  ioatdma: DMA copy alignment needed to address IOAT DMA silicon errata
  ioat: ring size variables need to be 32bit to avoid overflow
  iop-adma: Corrected array overflow in RAID6 Xscale(R) test.
  ioat: fix size of 'completion' for Xen
2012-04-10 15:30:16 -07:00
Dave Jiang
a2bd1140a2 netdma: adding alignment check for NETDMA ops
This is the fallout from adding memcpy alignment workaround for certain
IOATDMA hardware. NetDMA will only use DMA engine that can handle byte align
ops.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2012-04-05 15:27:12 -07:00
David S. Miller
4da0bd7365 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-03-18 23:29:41 -04:00
Joe Perches
afd465030a net: ipv4: Standardize prefixes for message logging
Add #define pr_fmt(fmt) as appropriate.

Add "IPv4: ", "TCP: ", and "IPsec: " to appropriate files.
Standardize on "UDPLite: " for appropriate uses.
Some prefixes were previously "UDPLITE: " and "UDP-Lite: ".

Add KBUILD_MODNAME ": " to icmp and gre.
Remove embedded prefixes as appropriate.

Add missing "\n" to pr_info in gre.c.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-12 17:05:21 -07:00
Joe Perches
058bd4d2a4 net: Convert printks to pr_<level>
Use a more current kernel messaging style.

Convert a printk block to print_hex_dump.
Coalesce formats, align arguments.
Use %s, __func__ instead of embedding function names.

Some messages that were prefixed with <foo>_close are
now prefixed with <foo>_fini.  Some ah4 and esp messages
are now not prefixed with "ip ".

The intent of this patch is to later add something like
  #define pr_fmt(fmt) "IPv4: " fmt.
to standardize the output messages.

Text size is trivially reduced. (x86-32 allyesconfig)

$ size net/ipv4/built-in.o*
   text	   data	    bss	    dec	    hex	filename
 887888	  31558	 249696	1169142	 11d6f6	net/ipv4/built-in.o.new
 887934	  31558	 249800	1169292	 11d78c	net/ipv4/built-in.o.old

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-11 23:42:51 -07:00
Eric Dumazet
dfd25ffffc tcp: fix syncookie regression
commit ea4fc0d619 (ipv4: Don't use rt->rt_{src,dst} in ip_queue_xmit())
added a serious regression on synflood handling.

Simon Kirby discovered a successful connection was delayed by 20 seconds
before being responsive.

In my tests, I discovered that xmit frames were lost, and needed ~4
retransmits and a socket dst rebuild before being really sent.

In case of syncookie initiated connection, we use a different path to
initialize the socket dst, and inet->cork.fl.u.ip4 is left cleared.

As ip_queue_xmit() now depends on inet flow being setup, fix this by
copying the temp flowi4 we use in cookie_v4_check().

Reported-by: Simon Kirby <sim@netnation.com>
Bisected-by: Simon Kirby <sim@netnation.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-11 15:52:12 -07:00
Eric Dumazet
b4fb05ea40 tcp: md5: correct a RCU lockdep splat
commit a8afca0329 (tcp: md5: protects md5sig_info with RCU) added a
lockdep splat in tcp_md5_do_lookup() in case a timer fires a tcp
retransmit.

At this point, socket lock is owned by the sofirq handler, not the user,
so we should adjust a bit the lockdep condition, as we dont hold
rcu_read_lock().

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-07 15:13:42 -05:00
Jiri Benc
4c507d2897 net: implement IP_RECVTOS for IP_PKTOPTIONS
Currently, it is not easily possible to get TOS/DSCP value of packets from
an incoming TCP stream. The mechanism is there, IP_PKTOPTIONS getsockopt
with IP_RECVTOS set, the same way as incoming TTL can be queried. This is
not actually implemented for TOS, though.

This patch adds this functionality, both for IPv4 (IP_PKTOPTIONS) and IPv6
(IPV6_2292PKTOPTIONS). For IPv4, like in the IP_RECVTTL case, the value of
the TOS field is stored from the other party's ACK.

This is needed for proxies which require DSCP transparency. One such example
is at http://zph.bratcheda.org/.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-13 00:46:41 -05:00
David S. Miller
d5ef8a4d87 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/infiniband/hw/nes/nes_cm.c

Simple whitespace conflict.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-10 23:32:28 -05:00
Shawn Lu
e2446eaab5 tcp_v4_send_reset: binding oif to iif in no sock case
Binding RST packet outgoing interface to incoming interface
for tcp v4 when there is no socket associate with it.
when sk is not NULL, using sk->sk_bound_dev_if instead.
(suggested by Eric Dumazet).

This has few benefits:
1. tcp_v6_send_reset already did that.
2. This helps tcp connect with SO_BINDTODEVICE set. When
connection is lost, we still able to sending out RST using
same interface.
3. we are sending reply, it is most likely to be succeed
if iif is used

Signed-off-by: Shawn Lu <shawn.lu@ericsson.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-04 18:20:05 -05:00
Shawn Lu
658ddaaf66 tcp: md5: RST: getting md5 key from listener
TCP RST mechanism is broken in TCP md5(RFC2385). When
connection is gone, md5 key is lost, sending RST
without md5 hash is deem to ignored by peer. This can
be a problem since RST help protocal like bgp to fast
recove from peer crash.

In most case, users of tcp md5, such as bgp and ldp,
have listener on both sides to accept connection from peer.
md5 keys for peers are saved in listening socket.

There are two cases in finding md5 key when connection is
lost:
1.Passive receive RST: The message is send to well known port,
tcp will associate it with listner. md5 key is gotten from
listener.

2.Active receive RST (no sock): The message is send to ative
side, there is no socket associated with the message. In this
case, finding listener from source port, then find md5 key from
listener.

we are not loosing sercuriy here:
packet is checked with md5 hash. No RST is generated
if md5 hash doesn't match or no md5 key can be found.

Signed-off-by: Shawn Lu <shawn.lu@ericsson.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-01 12:43:54 -05:00
Eric Dumazet
a8afca0329 tcp: md5: protects md5sig_info with RCU
This patch makes sure we use appropriate memory barriers before
publishing tp->md5sig_info, allowing tcp_md5_do_lookup() being used from
tcp_v4_send_reset() without holding socket lock (upcoming patch from
Shawn Lu)

Note we also need to respect rcu grace period before its freeing, since
we can free socket without this grace period thanks to
SLAB_DESTROY_BY_RCU

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Shawn Lu <shawn.lu@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-01 02:11:47 -05:00
Eric Dumazet
5f3d9cb296 tcp: md5: use sock_kmalloc() to limit md5 keys
There is no limit on number of MD5 keys an application can attach to a
tcp socket.

This patch adds a per tcp socket limit based
on /proc/sys/net/core/optmem_max

With current default optmem_max values, this allows about 150 keys on
64bit arches, and 88 keys on 32bit arches.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-31 16:11:48 -05:00
Eric Dumazet
a915da9b69 tcp: md5: rcu conversion
In order to be able to support proper RST messages for TCP MD5 flows, we
need to allow access to MD5 keys without locking listener socket.

This conversion is a nice cleanup, and shrinks size of timewait sockets
by 80 bytes.

IPv6 code reuses generic code found in IPv4 instead of duplicating it.

Control path uses GFP_KERNEL allocations instead of GFP_ATOMIC.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Shawn Lu <shawn.lu@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-31 12:14:00 -05:00
Eric Dumazet
a2d91241a8 tcp: md5: remove obsolete md5_add() method
We no longer use md5_add() method from struct tcp_sock_af_ops

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-31 12:13:59 -05:00
shawnlu
8a622e71f5 tcp: md5: using remote adress for md5 lookup in rst packet
md5 key is added in socket through remote address.
remote address should be used in finding md5 key when
sending out reset packet.

Signed-off-by: shawnlu <shawn.lu@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-22 15:08:45 -05:00
Glauber Costa
3dc43e3e4d per-netns ipv4 sysctl_tcp_mem
This patch allows each namespace to independently set up
its levels for tcp memory pressure thresholds. This patch
alone does not buy much: we need to make this values
per group of process somehow. This is achieved in the
patches that follows in this patchset.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
CC: David S. Miller <davem@davemloft.net>
CC: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-12 19:04:11 -05:00
Glauber Costa
d1a4c0b37c tcp memory pressure controls
This patch introduces memory pressure controls for the tcp
protocol. It uses the generic socket memory pressure code
introduced in earlier patches, and fills in the
necessary data in cg_proto struct.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujtisu.com>
CC: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-12 19:04:10 -05:00
Glauber Costa
180d8cd942 foundations of per-cgroup memory pressure controlling.
This patch replaces all uses of struct sock fields' memory_pressure,
memory_allocated, sockets_allocated, and sysctl_mem to acessor
macros. Those macros can either receive a socket argument, or a mem_cgroup
argument, depending on the context they live in.

Since we're only doing a macro wrapping here, no performance impact at all is
expected in the case where we don't have cgroups disabled.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com>
CC: David S. Miller <davem@davemloft.net>
CC: Eric W. Biederman <ebiederm@xmission.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-12 19:04:10 -05:00
Eric Dumazet
d8a6e65f8b tcp: inherit listener congestion control for passive cnx
Rick Jones reported that TCP_CONGESTION sockopt performed on a listener
was ignored for its children sockets : right after accept() the
congestion control for new socket is the system default one.

This seems an oversight of the initial design (quoted from Stephen)

Based on prior investigation and patch from Rick.

Reported-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Yuchung Cheng <ycheng@google.com>
Tested-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-30 16:55:26 -05:00
Eric Dumazet
709e8697af tcp: clear xmit timers in tcp_v4_syn_recv_sock()
Simon Kirby reported divides by zero errors in __tcp_select_window()

This happens when inet_csk_route_child_sock() returns a NULL pointer :

We free new socket while we eventually armed keepalive timer in
tcp_create_openreq_child()

Fix this by a call to tcp_clear_xmit_timers()

[ This is a followup to commit 918eb39962 (net: add missing
bh_unlock_sock() calls) ]

Reported-by: Simon Kirby <sim@hostway.ca>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Simon Kirby <sim@hostway.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-16 16:57:45 -05:00
Eric Dumazet
918eb39962 net: add missing bh_unlock_sock() calls
Simon Kirby reported lockdep warnings and following messages :

[104661.897577] huh, entered softirq 3 NET_RX ffffffff81613740
preempt_count 00000101, exited with 00000102?

[104661.923653] huh, entered softirq 3 NET_RX ffffffff81613740
preempt_count 00000101, exited with 00000102?

Problem comes from commit 0e734419
(ipv4: Use inet_csk_route_child_sock() in DCCP and TCP.)

If inet_csk_route_child_sock() returns NULL, we should release socket
lock before freeing it.

Another lock imbalance exists if __inet_inherit_port() returns an error
since commit 093d282321 ( tproxy: fix hash locking issue when using
port redirection in __inet_inherit_port()) a backport is also needed for
>= 2.6.37 kernels.

Reported-by: Simon Kirby <sim@hostway.ca>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Balazs Scheidler <bazsi@balabit.hu>
CC: KOVACS Krisztian <hidden@balabit.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Simon Kirby <sim@hostway.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-03 18:06:18 -04:00
Arjan van de Ven
73cb88ecb9 net: make the tcp and udp file_operations for the /proc stuff const
the tcp and udp code creates a set of struct file_operations at runtime
while it can also be done at compile time, with the added benefit of then
having these file operations be const.

the trickiest part was to get the "THIS_MODULE" reference right; the naive
method of declaring a struct in the place of registration would not work
for this reason.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-01 17:56:14 -04:00
Eric Dumazet
66b13d99d9 ipv4: tcp: fix TOS value in ACK messages sent from TIME_WAIT
There is a long standing bug in linux tcp stack, about ACK messages sent
on behalf of TIME_WAIT sockets.

In the IP header of the ACK message, we choose to reflect TOS field of
incoming message, and this might break some setups.

Example of things that were broken :
  - Routing using TOS as a selector
  - Firewalls
  - Trafic classification / shaping

We now remember in timewait structure the inet tos field and use it in
ACK generation, and route lookup.

Notes :
 - We still reflect incoming TOS in RST messages.
 - We could extend MuraliRaja Muniraju patch to report TOS value in
netlink messages for TIME_WAIT sockets.
 - A patch is needed for IPv6

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-24 03:06:21 -04:00
Eric Dumazet
318cf7aaa0 tcp: md5: add more const attributes
Now tcp_md5_hash_header() has a const tcphdr argument, we can add more
const attributes to callers.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-24 02:46:04 -04:00
Eric Dumazet
cf533ea53e tcp: add const qualifiers where possible
Adding const qualifiers to pointers can ease code review, and spot some
bugs. It might allow compiler to optimize code further.

For example, is it legal to temporary write a null cksum into tcphdr
in tcp_md5_hash_header() ? I am afraid a sniffer could catch the
temporary null value...

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-21 05:22:42 -04:00
David S. Miller
88c5100c28 Merge branch 'master' of github.com:davem330/net
Conflicts:
	net/batman-adv/soft-interface.c
2011-10-07 13:38:43 -04:00
Yan, Zheng
260fcbeb1a tcp: properly handle md5sig_pool references
tcp_v4_clear_md5_list() assumes that multiple tcp md5sig peers
only hold one reference to md5sig_pool. but tcp_v4_md5_do_add()
increases use count of md5sig_pool for each peer. This patch
makes tcp_v4_md5_do_add() only increases use count for the first
tcp md5sig peer.

Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-04 23:31:24 -04:00
Eric Dumazet
b82d1bb4fd tcp: unalias tcp_skb_cb flags and ip_dsfield
struct tcp_skb_cb contains a "flags" field containing either tcp flags
or IP dsfield depending on context (input or output path)

Introduce ip_dsfield to make the difference clear and ease maintenance.
If later we want to save space, we can union flags/ip_dsfield

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-27 02:20:08 -04:00
David S. Miller
8decf86879 Merge branch 'master' of github.com:davem330/net
Conflicts:
	MAINTAINERS
	drivers/net/Kconfig
	drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c
	drivers/net/ethernet/broadcom/tg3.c
	drivers/net/wireless/iwlwifi/iwl-pci.c
	drivers/net/wireless/iwlwifi/iwl-trans-tx-pcie.c
	drivers/net/wireless/rt2x00/rt2800usb.c
	drivers/net/wireless/wl12xx/main.c
2011-09-22 03:23:13 -04:00
Eric Dumazet
946cedccbd tcp: Change possible SYN flooding messages
"Possible SYN flooding on port xxxx " messages can fill logs on servers.

Change logic to log the message only once per listener, and add two new
SNMP counters to track :

TCPReqQFullDoCookies : number of times a SYNCOOKIE was replied to client

TCPReqQFullDrop : number of times a SYN request was dropped because
syncookies were not enabled.

Based on a prior patch from Tom Herbert, and suggestions from David.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-15 14:49:43 -04:00
Tom Herbert
bdeab99191 rps: Add flag to skb to indicate rxhash is based on L4 tuple
The l4_rxhash flag was added to the skb structure to indicate
that the rxhash value was computed over the 4 tuple for the
packet which includes the port information in the encapsulated
transport packet.  This is used by the stack to preserve the
rxhash value in __skb_rx_tunnel.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-17 20:06:03 -07:00
David S. Miller
6e5714eaf7 net: Compute protocol sequence numbers and fragment IDs using MD5.
Computers have become a lot faster since we compromised on the
partial MD4 hash which we use currently for performance reasons.

MD5 is a much safer choice, and is inline with both RFC1948 and
other ISS generators (OpenBSD, Solaris, etc.)

Furthermore, only having 24-bits of the sequence number be truly
unpredictable is a very serious limitation.  So the periodic
regeneration and 8-bit counter have been removed.  We compute and
use a full 32-bit sequence number.

For ipv6, DCCP was found to use a 32-bit truncated initial sequence
number (it needs 43-bits) and that is fixed here as well.

Reported-by: Dan Kaminsky <dan@doxpara.com>
Tested-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-06 18:33:19 -07:00
David S. Miller
9f6ec8d697 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
	drivers/net/wireless/rtlwifi/pci.c
	net/netfilter/ipvs/ip_vs_core.c
2011-06-20 22:29:08 -07:00
Eric Dumazet
1eddceadb0 net: rfs: enable RFS before first data packet is received
Le jeudi 16 juin 2011 à 23:38 -0400, David Miller a écrit :
> From: Ben Hutchings <bhutchings@solarflare.com>
> Date: Fri, 17 Jun 2011 00:50:46 +0100
>
> > On Wed, 2011-06-15 at 04:15 +0200, Eric Dumazet wrote:
> >> @@ -1594,6 +1594,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
> >>  			goto discard;
> >>
> >>  		if (nsk != sk) {
> >> +			sock_rps_save_rxhash(nsk, skb->rxhash);
> >>  			if (tcp_child_process(sk, nsk, skb)) {
> >>  				rsk = nsk;
> >>  				goto reset;
> >>
> >
> > I haven't tried this, but it looks reasonable to me.
> >
> > What about IPv6?  The logic in tcp_v6_do_rcv() looks very similar.
>
> Indeed ipv6 side needs the same fix.
>
> Eric please add that part and resubmit.  And in fact I might stick
> this into net-2.6 instead of net-next-2.6
>

OK, here is the net-2.6 based one then, thanks !

[PATCH v2] net: rfs: enable RFS before first data packet is received

First packet received on a passive tcp flow is not correctly RFS
steered.

One sock_rps_record_flow() call is missing in inet_accept()

But before that, we also must record rxhash when child socket is setup.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Tom Herbert <therbert@google.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
CC: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>
2011-06-17 15:27:31 -04:00
Jerry Chu
9ad7c049f0 tcp: RFC2988bis + taking RTT sample from 3WHS for the passive open side
This patch lowers the default initRTO from 3secs to 1sec per
RFC2988bis. It falls back to 3secs if the SYN or SYN-ACK packet
has been retransmitted, AND the TCP timestamp option is not on.

It also adds support to take RTT sample during 3WHS on the passive
open side, just like its active open counterpart, and uses it, if
valid, to seed the initRTO for the data transmission phase.

The patch also resets ssthresh to its initial default at the
beginning of the data transmission phase, and reduces cwnd to 1 if
there has been MORE THAN ONE retransmission during 3WHS per RFC5681.

Signed-off-by: H.K. Jerry Chu <hkchu@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-08 17:05:30 -07:00
Dan Rosenberg
71338aa7d0 net: convert %p usage to %pK
The %pK format specifier is designed to hide exposed kernel pointers,
specifically via /proc interfaces.  Exposing these pointers provides an
easy target for kernel write vulnerabilities, since they reveal the
locations of writable structures containing easily triggerable function
pointers.  The behavior of %pK depends on the kptr_restrict sysctl.

If kptr_restrict is set to 0, no deviation from the standard %p behavior
occurs.  If kptr_restrict is set to 1, the default, if the current user
(intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG
(currently in the LSM tree), kernel pointers using %pK are printed as 0's.
 If kptr_restrict is set to 2, kernel pointers using %pK are printed as
0's regardless of privileges.  Replacing with 0's was chosen over the
default "(null)", which cannot be parsed by userland %p, which expects
"(nil)".

The supporting code for kptr_restrict and %pK are currently in the -mm
tree.  This patch converts users of %p in net/ to %pK.  Cases of printing
pointers to the syslog are not covered, since this would eliminate useful
information for postmortem debugging and the reading of the syslog is
already optionally protected by the dmesg_restrict sysctl.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: James Morris <jmorris@namei.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Thomas Graf <tgraf@infradead.org>
Cc: Eugene Teo <eugeneteo@kernel.org>
Cc: Kees Cook <kees.cook@canonical.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David S. Miller <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-24 01:13:12 -04:00
David S. Miller
a48eff1288 ipv4: Pass explicit destination address to rt_bind_peer().
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-18 18:42:43 -04:00
David S. Miller
ed2361e66e ipv4: Pass explicit destination address to rt_get_peer().
This will next trickle down to rt_bind_peer().

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-18 18:38:54 -04:00
David S. Miller
6bd023f3dd ipv4: Make caller provide flowi4 key to inet_csk_route_req().
This way the caller can get at the fully resolved fl4->{daddr,saddr}
etc.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-18 18:32:03 -04:00
David S. Miller
0a5ebb8000 ipv4: Pass explicit daddr arg to ip_send_reply().
This eliminates an access to rt->rt_src.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-10 13:32:46 -07:00
David S. Miller
c5216cc70f tcp: Use cork flow info instead of rt->rt_dst in tcp_v4_get_peer()
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08 15:28:29 -07:00
David S. Miller
0e73441992 ipv4: Use inet_csk_route_child_sock() in DCCP and TCP.
Operation order is now transposed, we first create the child
socket then we try to hook up the route.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08 15:28:03 -07:00
David S. Miller
da905bd1d5 tcp: Use cork flow in tcp_v4_connect()
Since this is invoked from inet_stream_connect() the socket is locked
and therefore this usage is safe.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08 13:18:54 -07:00
David S. Miller
d4fb3d74d7 ipv4: Get route daddr from flow key in tcp_v4_connect().
Now that output route lookups update the flow with
destination address selection, we can fetch it from
fl4->daddr instead of rt->rt_dst

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28 23:50:32 -07:00
David S. Miller
4071cfff84 ipv4: Fetch route saddr from flow key in tcp_v4_connect().
Now that output route lookups update the flow with
source address selection, we can fetch it from
fl4->saddr instead of rt->rt_src

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28 23:17:31 -07:00
Eric Dumazet
f6d8bd051c inet: add RCU protection to inet->opt
We lack proper synchronization to manipulate inet->opt ip_options

Problem is ip_make_skb() calls ip_setup_cork() and
ip_setup_cork() possibly makes a copy of ipc->opt (struct ip_options),
without any protection against another thread manipulating inet->opt.

Another thread can change inet->opt pointer and free old one under us.

Use RCU to protect inet->opt (changed to inet->inet_opt).

Instead of handling atomic refcounts, just copy ip_options when
necessary, to avoid cache line dirtying.

We cant insert an rcu_head in struct ip_options since its included in
skb->cb[], so this patch is large because I had to introduce a new
ip_options_rcu structure.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-28 13:16:35 -07:00
David S. Miller
2d7192d6cb ipv4: Sanitize and simplify ip_route_{connect,newports}()
These functions are used together as a unit for route resolution
during connect().  They address the chicken-and-egg problem that
exists when ports need to be allocated during connect() processing,
yet such port allocations require addressing information from the
routing code.

It's currently more heavy handed than it needs to be, and in
particular we allocate and initialize a flow object twice.

Let the callers provide the on-stack flow object.  That way we only
need to initialize it once in the ip_route_connect() call.

Later, if ip_route_newports() needs to do anything, it re-uses that
flow object as-is except for the ports which it updates before the
route re-lookup.

Also, describe why this set of facilities are needed and how it works
in a big comment.

Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
2011-04-27 13:59:04 -07:00
Eric Dumazet
b71d1d426d inet: constify ip headers and in6_addr
Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers
where possible, to make code intention more obvious.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-22 11:04:14 -07:00