Commit Graph

68 Commits

Author SHA1 Message Date
Jesper Juhl
77933d7276 [PATCH] clean up inline static vs static inline
`gcc -W' likes to complain if the static keyword is not at the beginning of
the declaration.  This patch fixes all remaining occurrences of "inline
static" up with "static inline" in the entire kernel tree (140 occurrences in
47 files).

While making this change I came across a few lines with trailing whitespace
that I also fixed up, I have also added or removed a blank line or two here
and there, but there are no functional changes in the patch.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:20 -07:00
David S. Miller
b72f6eccb0 [NET]: Fix tc_verd thinko in skb_clone()
It was overwriting the computer n->tc_verd value over
and over with skb->tc_verd, by mistake.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-19 14:13:54 -07:00
Patrick McHardy
6aef4fdfea [NET]: Only build flow.o if CONFIG_XFRM=y
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-19 13:58:40 -07:00
Victor Fusco
86a76caf87 [NET]: Fix sparse warnings
From: Victor Fusco <victor@cetuc.puc-rio.br>

Fix the sparse warning "implicit cast to nocast type"

Signed-off-by: Victor Fusco <victor@cetuc.puc-rio.br>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 14:57:47 -07:00
David Chau
52609c0b56 [NET]: improve readability of dev_set_promiscuity() in net/core/dev.c
A trivial patch to improve the readability of dev_set_promiscuity()
in net/core/dev.c. New code does exactly the same thing as original
code.

Signed-off-by: David Chau <ddcc@mit.edu>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:11:06 -07:00
Thomas Graf
e176fe8954 [NET]: Remove unused security member in sk_buff
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:12:44 -07:00
Patrick McHardy
3154e540e3 [NET]: net/core/filter.c: make len cover the entire packet
As suggested by Herbert Xu:

Since we don't require anything to be in the linear packet range
anymore make len cover the entire packet.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:10:40 -07:00
Patrick McHardy
0b05b2a49e [NET]: Consolidate common code in net/core/filter.c
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:10:21 -07:00
Patrick McHardy
6935d46c2d [NET]: Remove redundant code in net/core/filter.c
skb_header_pointer handles linear and non-linear data, no need to handle
linear data again.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:08:57 -07:00
Patrick McHardy
9ef1d4c7c7 [NETLINK]: Missing initializations in dumped data
Mostly missing initialization of padding fields of 1 or 2 bytes length,
two instances of uninitialized nlmsgerr->msg of 16 bytes length.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 12:55:30 -07:00
Patrick McHardy
b3563c4fbf [NETLINK]: Clear padding in netlink messages
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 12:54:43 -07:00
Robert Olsson
64053beeb5 [PKTGEN]: Fix random packet sizes causing panic
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-26 15:27:10 -07:00
Thomas Graf
3fc7e8a6d8 [NET]: skb_find_text() - Find a text pattern in skb data
Finds a pattern in the skb data according to the specified
textsearch configuration. Use textsearch_next() to retrieve
subsequent occurrences of the pattern. Returns the offset
to the first occurrence or UINT_MAX if no match was found.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 21:00:17 -07:00
Thomas Graf
677e90eda3 [NET]: Zerocopy sequential reading of skb data
Implements sequential reading for both linear and non-linear
skb data at zerocopy cost. The data is returned in chunks of
arbitary length, therefore random access is not possible.

Usage:
	from	 := 0
	to	 := 128
	state	 := undef
	data	 := undef
	len	 := undef
	consumed := 0

	skb_prepare_seq_read(skb, from, to, &state)
	while (len = skb_seq_read(consumed, &data, &state)) != 0 do
		/* do something with 'data' of length 'len' */
		if abort then
			/* abort read if we don't wait for
			 * skb_seq_read() to return 0 */
			skb_abort_seq_read(&state)
			return
		endif
		/* not necessary to consume all of 'len' */
		consumed += len
	done

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 20:59:51 -07:00
Stephen Hemminger
51b0bdedb8 [NET]: Separate two usages of netdev_max_backlog.
Separate out the two uses of netdev_max_backlog. One controls the
upper bound on packets processed per softirq, the new name for this is
netdev_budget; the other controls the limit on packets queued via
netif_rx.

Increase the max_backlog default to account for faster processors.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 20:14:40 -07:00
Stephen Hemminger
31aa02c53c [NET]: Eliminate netif_rx massive packet drops.
Eliminate the throttling behaviour when the netif receive queue fills
because it behaves badly when using high speed networks under load.
The throttling cause multiple packet drops that cause TCP to go into
slow start mode. The same effective patch has been part of BIC TCP and
H-TCP as well as part of Web100.

The existing code drops 100's of packets when the queue fills;
this changes it to individual packet drop-tail. 

Signed-off-by: Stephen Hemmminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 20:12:48 -07:00
Stephen Hemminger
34008d8c63 [NET]: Remove obsolete netif_rx congestion sensing mechanism.
Remove the congestion sensing mechanism from netif_rx, and always
return either full or empty.  Almost no driver checks the return value
from netif_rx, and those that do only use it for debug messages.

The original design of netif_rx was to do flow control based on the
receive queue, but NAPI has supplanted this and no driver uses the
feedback.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 20:10:00 -07:00
Stephen Hemminger
c1ebcdb8c4 [NET]: Remove obsolete fastroute stats.
Remove last vestiages of fastroute code that is no longer used.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 20:08:59 -07:00
Paulo Marques
543537bd92 [PATCH] create a kstrdup library function
This patch creates a new kstrdup library function and changes the "local"
implementations in several places to use this function.

Most of the changes come from the sound and net subsystems.  The sound part
had already been acknowledged by Takashi Iwai and the net part by David S.
Miller.

I left UML alone for now because I would need more time to read the code
carefully before making changes there.

Signed-off-by: Paulo Marques <pmarques@grupopie.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:18 -07:00
Jeff Moyer
fbeec2e155 [NETPOLL]: allow multiple netpoll_clients to register against one interface
This patch provides support for registering multiple netpoll clients to the
same network device.  Only one of these clients may register an rx_hook,
however.  In practice, this restriction has not been problematic.  It is
worth mentioning, though, that the current design can be easily extended to
allow for the registration of multiple rx_hooks.

The basic idea of the patch is that the rx_np pointer in the netpoll_info
structure points to the struct netpoll that has rx_hook filled in.  Aside
from this one case, there is no need for a pointer from the struct
net_device to an individual struct netpoll.

A lock is introduced to protect the setting and clearing of the np_rx
pointer.  The pointer will only be cleared upon netpoll client module
removal, and the lock should be uncontested.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:05:59 -07:00
Jeff Moyer
115c1d6e61 [NETPOLL]: Introduce a netpoll_info struct
This patch introduces a netpoll_info structure, which the struct net_device
will now point to instead of pointing to a struct netpoll.  The reason for
this is two-fold: 1) fields such as the rx_flags, poll_owner, and poll_lock
should be maintained per net_device, not per netpoll;  and 2) this is a first
step in providing support for multiple netpoll clients to register against the
same net_device.

The struct netpoll is now pointed to by the netpoll_info structure.  As
such, the previous behaviour of the code is preserved.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:05:31 -07:00
Patrick McHardy
18b8afc771 [NETFILTER]: Kill nf_debug
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:01:57 -07:00
Jamal Hadi Salim
9ed19f339e [NETLINK]: Set correct pid for ioctl originating netlink events
This patch ensures that netlink events created as a result of programns
using ioctls (such as ifconfig, route etc) contains the correct PID of
those events.
 
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:55:51 -07:00
Jamal Hadi Salim
b6544c0b4c [NETLINK]: Correctly set NLM_F_MULTI without checking the pid
This patch rectifies some rtnetlink message builders that derive the
flags from the pid. It is now explicit like the other cases
which get it right. Also fixes half a dozen dumpers which did not
set NLM_F_MULTI at all.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:54:12 -07:00
Thomas Graf
1797754ea7 [NETLINK]: Introduce NLMSG_NEW macro to better handle netlink flags
Introduces a new macro NLMSG_NEW which extends NLMSG_PUT but takes
a flags argument. NLMSG_PUT stays there for compatibility but now
calls NLMSG_NEW with flags == 0. NLMSG_PUT_ANSWER is renamed to
NLMSG_NEW_ANSWER which now also takes a flags argument.

Also converts the users of NLMSG_PUT_ANSWER to use NLMSG_NEW_ANSWER
and fixes the two direct users of __nlmsg_put to either provide
the flags or use NLMSG_NEW(_ANSWER).

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:53:48 -07:00
Thomas Graf
e386c6eb43 [NEIGH]: Fix use of uninitialized variable when trimming in neightbl_fill_parms
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:52:09 -07:00
Thomas Graf
4b6ea82dd1 [NETLINK]: Kill bogus NLMSG_SET_MULTIPART uses.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:51:43 -07:00
Thomas Graf
c7fb64db00 [NETLINK]: Neighbour table configuration and statistics via rtnetlink
To retrieve the neighbour tables send RTM_GETNEIGHTBL with the
NLM_F_DUMP flag set. Every neighbour table configuration is
spread over multiple messages to avoid running into message
size limits on systems with many interfaces. The first message
in the sequence transports all not device specific data such as
statistics, configuration, and the default parameter set.
This message is followed by 0..n messages carrying device
specific parameter sets.

Although the ordering should be sufficient, NDTA_NAME can be
used to identify sequences. The initial message can be identified
by checking for NDTA_CONFIG. The device specific messages do
not contain this TLV but have NDTPA_IFINDEX set to the
corresponding interface index.

To change neighbour table attributes, send RTM_SETNEIGHTBL
with NDTA_NAME set. Changeable attribute include NDTA_THRESH[1-3],
NDTA_GC_INTERVAL, and all TLVs in NDTA_PARMS unless marked
otherwise. Device specific parameter sets can be changed by
setting NDTPA_IFINDEX to the interface index of the corresponding
device.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:50:55 -07:00
David S. Miller
e52c1f17e4 [NET]: Move sysctl_max_syn_backlog into request_sock.c
This fixes the CONFIG_INET=n build failure noticed
by Andrew Morton.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:49:40 -07:00
Arnaldo Carvalho de Melo
2ad69c55a2 [NET] rename struct tcp_listen_opt to struct listen_sock
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:48:55 -07:00
Arnaldo Carvalho de Melo
0e87506fcc [NET] Generalise tcp_listen_opt
This chunks out the accept_queue and tcp_listen_opt code and moves
them to net/core/request_sock.c and include/net/request_sock.h, to
make it useful for other transport protocols, DCCP being the first one
to use it.

Next patches will rename tcp_listen_opt to accept_sock and remove the
inline tcp functions that just call a reqsk_queue_ function.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:47:59 -07:00
Arnaldo Carvalho de Melo
2e6599cb89 [NET] Generalise TCP's struct open_request minisock infrastructure
Kept this first changeset minimal, without changing existing names to
ease peer review.

Basicaly tcp_openreq_alloc now receives the or_calltable, that in turn
has two new members:

->slab, that replaces tcp_openreq_cachep
->obj_size, to inform the size of the openreq descendant for
  a specific protocol

The protocol specific fields in struct open_request were moved to a
class hierarchy, with the things that are common to all connection
oriented PF_INET protocols in struct inet_request_sock, the TCP ones
in tcp_request_sock, that is an inet_request_sock, that is an
open_request.

I.e. this uses the same approach used for the struct sock class
hierarchy, with sk_prot indicating if the protocol wants to use the
open_request infrastructure by filling in sk_prot->rsk_prot with an
or_calltable.

Results? Performance is improved and TCP v4 now uses only 64 bytes per
open request minisock, down from 96 without this patch :-)

Next changeset will rename some of the structs, fields and functions
mentioned above, struct or_calltable is way unclear, better name it
struct request_sock_ops, s/struct open_request/struct request_sock/g,
etc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:46:52 -07:00
Linus Torvalds
0e396ee43e Manual merge of rsync://rsync.kernel.org/pub/scm/linux/kernel/git/jgarzik/netdev-2.6.git
This is a fixed-up version of the broken "upstream-2.6.13" branch, where
I re-did the manual merge of drivers/net/r8169.c by hand, and made sure
the history is all good.
2005-06-18 11:42:35 -07:00
Stephen Hemminger
e387660545 [NET]: Fix sysctl net.core.dev_weight
Changing the sysctl net.core.dev_weight has no effect because the weight
of the backlog devices is set during initialization and never changed.

This patch propagates any changes to the global value affected by sysctl
to the per-cpu devices. It is done every time the packet handler
function is run.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-08 14:56:01 -07:00
Stephen Hemminger
699a411451 [NET]: Allow controlling NAPI device weight with sysfs
Simple interface to allow changing network device scheduling weight
with sysfs. Please consider this for 2.6.12, since risk/impact is small.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-08 14:55:42 -07:00
David S. Miller
fa04ae5c09 [ETHTOOL]: Check correct pointer in ethtool_set_coalesce().
It was checking the "GET" function pointer instead of
the "SET" one.  Looks like a cut&paste error :-)

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-06 15:07:19 -07:00
91bcc018f9 Automatic merge of /spare/repo/netdev-2.6 branch we18 2005-06-04 17:08:24 -04:00
David S. Miller
d1102b59ca [NET]: Use %lx for netdev->features sysfs formatting.
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-29 20:28:25 -07:00
Jon Mason
69f6a0fafc [NET]: Add ethtool support for NETIF_F_HW_CSUM.
Signed-off-by: Jon Mason <jdmason@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-29 20:27:24 -07:00
Stephen Hemminger
81e8157583 [BRIDGE]: make dev->features unsigned
The features field in netdevice is really a bitmask, and bitmask's should
be unsigned.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-29 14:14:35 -07:00
Stephen Hemminger
d8a33ac435 [BRIDGE]: features change notification
Resend of earlier patch (no changes) from Catalin used to provide
device feature change notification.

Signed-off-by: Catalin BOIE <catab at umbrella.ro>
Acked-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-29 14:13:47 -07:00
fff9cfd99c [PATCH] Wireless Extensions 18 (aka WPA)
This is version 18 of the Wireless Extensions. The main change
  is that it adds all the necessary APIs for WPA and WPA2 support. This
  work was entirely done by Jouni Malinen, so let's thank him for both
  his hard work and deep expertise on the subject ;-)
        This APIs obviously doesn't do much by itself and works in
  concert with driver support (Jouni already sent you the HostAP
  changes) and userspace (Jouni is updating wpa_supplicant). This is
  also orthogonal with the ongoing work on in-kernel IEEE support (but
  potentially useful).
        The patch is attached, tested with 2.6.11. Normally, I would
  ask you to push that directly in the kernel (99% of the patch has been
  on my web page for ages and it does not affect non-WPA stuff), but
  Jouni convinced me that it should bake a few weeks in wireless-2.6
  first, so that other driver maintainers can get up to speed with it.
  
  Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-05-12 20:24:19 -04:00
Jesper Juhl
02c30a84e6 [PATCH] update Ross Biro bouncing email address
Ross moved.  Remove the bad email address so people will find the correct
one in ./CREDITS.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:49 -07:00
Arnaldo Carvalho de Melo
476e19cfa1 [IPV6]: Fix OOPS when using IPV6_ADDRFORM
This causes sk->sk_prot to change, which makes the socket
release free the sock into the wrong SLAB cache.  Fix this
by introducing sk_prot_creator so that we always remember
where the sock came from.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-05 13:35:15 -07:00
Patrick McHardy
bd96535b81 [NETFILTER]: Drop conntrack reference in ip_dev_loopback_xmit()
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-03 16:21:37 -07:00
Patrick McHardy
e4f8ab00cf [NETFILTER]: Fix nf_debug_ip_local_deliver()
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-03 16:20:39 -07:00
Tommy S. Christensen
cacaddf57e [NET]: Disable queueing when carrier is lost.
Some network drivers call netif_stop_queue() when detecting loss of
carrier. This leads to packets being queued up at the qdisc level for
an unbound period of time. In order to prevent this effect, the core
networking stack will now cease to queue packets for any device, that
is operationally down (i.e. the queue is flushed and disabled).

Signed-off-by: Tommy S. Christensen <tommy.christensen@tpack.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-03 16:18:52 -07:00
David S. Miller
0f4821e7b9 [XFRM/RTNETLINK]: Decrement qlen properly in {xfrm_,rt}netlink_rcv().
If we free up a partially processed packet because it's
skb->len dropped to zero, we need to decrement qlen because
we are dropping out of the top-level loop so it will do
the decrement for us.

Spotted by Herbert Xu.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-03 16:15:59 -07:00
David S. Miller
09e1430598 [NETLINK]: Fix infinite loops in synchronous netlink changes.
The qlen should continue to decrement, even if we
pop partially processed SKBs back onto the receive queue.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-03 15:30:05 -07:00
Herbert Xu
2a0a6ebee1 [NETLINK]: Synchronous message processing.
Let's recap the problem.  The current asynchronous netlink kernel
message processing is vulnerable to these attacks:

1) Hit and run: Attacker sends one or more messages and then exits
before they're processed.  This may confuse/disable the next netlink
user that gets the netlink address of the attacker since it may
receive the responses to the attacker's messages.

Proposed solutions:

a) Synchronous processing.
b) Stream mode socket.
c) Restrict/prohibit binding.

2) Starvation: Because various netlink rcv functions were written
to not return until all messages have been processed on a socket,
it is possible for these functions to execute for an arbitrarily
long period of time.  If this is successfully exploited it could
also be used to hold rtnl forever.

Proposed solutions:

a) Synchronous processing.
b) Stream mode socket.

Firstly let's cross off solution c).  It only solves the first
problem and it has user-visible impacts.  In particular, it'll
break user space applications that expect to bind or communicate
with specific netlink addresses (pid's).

So we're left with a choice of synchronous processing versus
SOCK_STREAM for netlink.

For the moment I'm sticking with the synchronous approach as
suggested by Alexey since it's simpler and I'd rather spend
my time working on other things.

However, it does have a number of deficiencies compared to the
stream mode solution:

1) User-space to user-space netlink communication is still vulnerable.

2) Inefficient use of resources.  This is especially true for rtnetlink
since the lock is shared with other users such as networking drivers.
The latter could hold the rtnl while communicating with hardware which
causes the rtnetlink user to wait when it could be doing other things.

3) It is still possible to DoS all netlink users by flooding the kernel
netlink receive queue.  The attacker simply fills the receive socket
with a single netlink message that fills up the entire queue.  The
attacker then continues to call sendmsg with the same message in a loop.

Point 3) can be countered by retransmissions in user-space code, however
it is pretty messy.

In light of these problems (in particular, point 3), we should implement
stream mode netlink at some point.  In the mean time, here is a patch
that implements synchronous processing.  

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-03 14:55:09 -07:00