linux-toradex.git/net/ipv4/inet_hashtables.c, branch v3.2.49

net: Compute protocol sequence numbers and fragment IDs using MD5.

2011-08-07T01:33:19+00:00

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 
Tested-by: Willy Tarreau 
Signed-off-by: David S. Miller

inet: Fix __inet_inherit_port() to correctly increment bsockets and num_owners

2010-11-29T02:18:44+00:00

inet sockets corresponding to passive connections are added to the bind hash
using ___inet_inherit_port(). These sockets are later removed from the bind
hash using __inet_put_port(). These two functions are not exactly symmetrical.
__inet_put_port() decrements hashinfo->bsockets and tb->num_owners, whereas
___inet_inherit_port() does not increment them. This results in both of these
going to -ve values.

This patch fixes this by calling inet_bind_hash() from ___inet_inherit_port(),
which does the right thing.

'bsockets' and 'num_owners' were introduced by commit a9d8f9110d7e953c
(inet: Allowing more than 64k connections and heavily optimize bind(0))

Signed-off-by: Nagendra Singh Tomar 
Acked-by: Eric Dumazet 
Acked-by: Evgeniy Polyakov 
Signed-off-by: David S. Miller

tproxy: fix hash locking issue when using port redirection in __inet_inherit_port()

2010-10-21T11:06:43+00:00

When __inet_inherit_port() is called on a tproxy connection the wrong locks are
held for the inet_bind_bucket it is added to. __inet_inherit_port() made an
implicit assumption that the listener's port number (and thus its bind bucket).
Unfortunately, if you're using the TPROXY target to redirect skbs to a
transparent proxy that assumption is not true anymore and things break.

This patch adds code to __inet_inherit_port() so that it can handle this case
by looking up or creating a new bind bucket for the child socket and updates
callers of __inet_inherit_port() to gracefully handle __inet_inherit_port()
failing.

Reported by and original patch from Stephen Buck .
See http://marc.info/?t=128169268200001&r=1&w=2 for the original discussion.

Signed-off-by: KOVACS Krisztian 
Signed-off-by: Patrick McHardy

net/ipv4: EXPORT_SYMBOL cleanups

2010-07-12T19:57:54+00:00

CodingStyle cleanups

EXPORT_SYMBOL should immediately follow the symbol declaration.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: reserve ports for applications using fixed port numbers

2010-05-16T06:28:40+00:00

(Dropped the infiniband part, because Tetsuo modified the related code,
I will send a separate patch for it once this is accepted.)

This patch introduces /proc/sys/net/ipv4/ip_local_reserved_ports which
allows users to reserve ports for third-party applications.

The reserved ports will not be used by automatic port assignments
(e.g. when calling connect() or bind() with port number 0). Explicit
port allocation behavior is unchanged.

Signed-off-by: Octavian Purdila 
Signed-off-by: WANG Cong 
Cc: Neil Horman 
Cc: Eric Dumazet 
Cc: Eric W. Biederman 
Signed-off-by: David S. Miller

tcp: Fix a connect() race with timewait sockets

2009-12-09T04:17:51+00:00

When we find a timewait connection in __inet_hash_connect() and reuse
it for a new connection request, we have a race window, releasing bind
list lock and reacquiring it in __inet_twsk_kill() to remove timewait
socket from list.

Another thread might find the timewait socket we already chose, leading to
list corruption and crashes.

Fix is to remove timewait socket from bind list before releasing the bind lock.

Note: This problem happens if sysctl_tcp_tw_reuse is set.

Reported-by: kapil dakhane 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

tcp: Fix a connect() race with timewait sockets

2009-12-09T04:17:51+00:00

First patch changes __inet_hash_nolisten() and __inet6_hash()
to get a timewait parameter to be able to unhash it from ehash
at same time the new socket is inserted in hash.

This makes sure timewait socket wont be found by a concurrent
writer in __inet_check_established()

Reported-by: kapil dakhane 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

tcp: connect() race with timewait reuse

2009-12-04T00:17:43+00:00

Its currently possible that several threads issuing a connect() find
the same timewait socket and try to reuse it, leading to list
corruptions.

Condition for bug is that these threads bound their socket on same
address/port of to-be-find timewait socket, and connected to same
target. (SO_REUSEADDR needed)

To fix this problem, we could unhash timewait socket while holding
ehash lock, to make sure lookups/changes will be serialized. Only
first thread finds the timewait socket, other ones find the
established socket and return an EADDRNOTAVAIL error.

This second version takes into account Evgeniy's review and makes sure
inet_twsk_put() is called outside of locked sections.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: use net_eq to compare nets

2009-11-25T23:14:13+00:00

Generated with the following semantic patch

@@
struct net *n1;
struct net *n2;
@@
- n1 == n2
+ net_eq(n1, n2)

@@
struct net *n1;
struct net *n2;
@@
- n1 != n2
+ !net_eq(n1, n2)

applied over {include,net,drivers/net}.

Signed-off-by: Octavian Purdila 
Signed-off-by: David S. Miller

inet: rename some inet_sock fields

2009-10-19T01:52:53+00:00

In order to have better cache layouts of struct sock (separate zones
for rx/tx paths), we need this preliminary patch.

Goal is to transfert fields used at lookup time in the first
read-mostly cache line (inside struct sock_common) and move sk_refcnt
to a separate cache line (only written by rx path)

This patch adds inet_ prefix to daddr, rcv_saddr, dport, num, saddr,
sport and id fields. This allows a future patch to define these
fields as macros, like sk_refcnt, without name clashes.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller