linux.git/net/dccp/ipv6.c, branch v3.9

inet: Fix kmemleak in tcp_v4/6_syn_recv_sock and dccp_v4/6_request_recv_sock

2012-12-14T18:14:07+00:00

If in either of the above functions inet_csk_route_child_sock() or
__inet_inherit_port() fails, the newsk will not be freed:

unreferenced object 0xffff88022e8a92c0 (size 1592):
  comm "softirq", pid 0, jiffies 4294946244 (age 726.160s)
  hex dump (first 32 bytes):
    0a 01 01 01 0a 01 01 02 00 00 00 00 a7 cc 16 00  ................
    02 00 03 01 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [] kmemleak_alloc+0x21/0x3e
    [] kmem_cache_alloc+0xb5/0xc5
    [] sk_prot_alloc.isra.53+0x2b/0xcd
    [] sk_clone_lock+0x16/0x21e
    [] inet_csk_clone_lock+0x10/0x7b
    [] tcp_create_openreq_child+0x21/0x481
    [] tcp_v4_syn_recv_sock+0x3a/0x23b
    [] tcp_check_req+0x29f/0x416
    [] tcp_v4_do_rcv+0x161/0x2bc
    [] tcp_v4_rcv+0x6c9/0x701
    [] ip_local_deliver_finish+0x70/0xc4
    [] ip_local_deliver+0x4e/0x7f
    [] ip_rcv_finish+0x1fc/0x233
    [] ip_rcv+0x217/0x267
    [] __netif_receive_skb+0x49e/0x553
    [] netif_receive_skb+0x50/0x82

This happens, because sk_clone_lock initializes sk_refcnt to 2, and thus
a single sock_put() is not enough to free the memory. Additionally, things
like xfrm, memcg, cookie_values,... may have been initialized.
We have to free them properly.

This is fixed by forcing a call to tcp_done(), ending up in
inet_csk_destroy_sock, doing the final sock_put(). tcp_done() is necessary,
because it ends up doing all the cleanup on xfrm, memcg, cookie_values,
xfrm,...

Before calling tcp_done, we have to set the socket to SOCK_DEAD, to
force it entering inet_csk_destroy_sock. To avoid the warning in
inet_csk_destroy_sock, inet_num has to be set to 0.
As inet_csk_destroy_sock does a dec on orphan_count, we first have to
increase it.

Calling tcp_done() allows us to remove the calls to
tcp_clear_xmit_timer() and tcp_cleanup_congestion_control().

A similar approach is taken for dccp by calling dccp_done().

This is in the kernel since 093d282321 (tproxy: fix hash locking issue
when using port redirection in __inet_inherit_port()), thus since
version >= 2.6.37.

Signed-off-by: Christoph Paasch 
Signed-off-by: David S. Miller

net: Pass optional SKB and SK arguments to dst_ops->{update_pmtu,redirect}()

2012-07-17T10:29:28+00:00

This will be used so that we can compose a full flow key.

Even though we have a route in this context, we need more.  In the
future the routes will be without destination address, source address,
etc. keying.  One ipv4 route will cover entire subnets, etc.

In this environment we have to have a way to possess persistent storage
for redirects and PMTU information.  This persistent storage will exist
in the FIB tables, and that's why we'll need to be able to rebuild a
full lookup flow key here.  Using that flow key will do a fib_lookup()
and create/update the persistent entry.

Signed-off-by: David S. Miller

ipv6: Add helper inet6_csk_update_pmtu().

2012-07-16T10:44:56+00:00

This is the ipv6 version of inet_csk_update_pmtu().

Signed-off-by: David S. Miller

net: Remove checks for dst_ops->redirect being NULL.

2012-07-12T07:41:25+00:00

No longer necessary.

Signed-off-by: David S. Miller

ipv6: Add redirect support to all protocol icmp error handlers.

2012-07-12T07:25:15+00:00

Signed-off-by: David S. Miller

dccp: remove unnecessary codes in ipv6.c

2012-07-05T10:11:15+00:00

opt always equals np->opts, so it is meaningless to define opt, and
check if opt does not equal np->opts and then try to free opt.

Signed-off-by: RongQing.Li 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller

ipv6: Handle PMTU in ICMP error handlers.

2012-06-15T21:54:11+00:00

One tricky issue on the ipv6 side vs. ipv4 is that the ICMP callouts
to handle the error pass the 32-bit info cookie in network byte order
whereas ipv4 passes it around in host byte order.

Like the ipv4 side, we have two helper functions.  One for when we
have a socket context and one for when we do not.

ip6ip6 tunnels are not handled here, because they handle PMTU events
by essentially relaying another ICMP packet-too-big message back to
the original sender.

This patch allows us to get rid of rt6_do_pmtu_disc().  It handles all
kinds of situations that simply cannot happen when we do the PMTU
update directly using a fully resolved route.

In fact, the "plen == 128" check in ip6_rt_update_pmtu() can very
likely be removed or changed into a BUG_ON() check.  We should never
have a prefixed ipv6 route when we get there.

Another piece of strange history here is that TCP and DCCP, unlike in
ipv4, never invoke the update_pmtu() method from their ICMP error
handlers.  This is incredibly astonishing since this is the context
where we have the most accurate context in which to make a PMTU
update, namely we have a fully connected socket and associated cached
socket route.

Signed-off-by: David S. Miller

ipv6: dccp: dont drop packet but consume it

2012-04-19T18:23:55+00:00

When we need to clone skb, we dont drop a packet.
Call consume_skb() to not confuse dropwatch.

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

inet: makes syn_ack_timeout mandatory

2012-04-14T19:24:26+00:00

There are two struct request_sock_ops providers, tcp and dccp.

inet_csk_reqsk_queue_prune() can avoid testing syn_ack_timeout being
NULL if we make it non NULL like syn_ack_timeout

Signed-off-by: Eric Dumazet 
Cc: Gerrit Renker 
Cc: dccp@vger.kernel.org
Signed-off-by: David S. Miller

dccp: fix bug in sequence number validation during connection setup

2012-03-03T16:02:52+00:00

This fixes a bug in the sequence number validation during the initial handshake.

The code did not treat the initial sequence numbers ISS and ISR as read-only and
did not keep state for GSR and GSS as required by the specification. This causes
problems with retransmissions during the initial handshake, causing the
budding connection to be reset.

This patch now treats ISS/ISR as read-only and tracks GSS/GSR as required.

Signed-off-by: Samuel Jero 
Signed-off-by: Gerrit Renker