Commit Graph

4357 Commits

Author SHA1 Message Date
Eric Dumazet 33d480ce6d net: cleanup some rcu_dereference_raw
RCU api had been completed and rcu_access_pointer() or
rcu_dereference_protected() are better than generic
rcu_dereference_raw()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-12 02:55:28 -07:00
David S. Miller 19fd61785a Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net 2011-08-07 23:20:26 -07:00
Julian Anastasov d52fbfc9e5 ipv4: use dst with ref during bcast/mcast loopback
Make sure skb dst has reference when moving to
another context. Currently, I don't see protocols that can
hit it when sending broadcasts/multicasts to loopback using
noref dsts, so it is just a precaution.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07 22:52:32 -07:00
Julian Anastasov 47670b767b ipv4: route non-local sources for raw socket
The raw sockets can provide source address for
routing but their privileges are not considered. We
can provide non-local source address, make sure the
FLOWI_FLAG_ANYSRC flag is set if socket has privileges
for this, i.e. based on hdrincl (IP_HDRINCL) and
transparent flags.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07 22:52:32 -07:00
Julian Anastasov 797fd3913a netfilter: TCP and raw fix for ip_route_me_harder
TCP in some cases uses different global (raw) socket
to send RST and ACK. The transparent flag is not set there.
Currently, it is a problem for rerouting after the previous
change.

	Fix it by simplifying the checks in ip_route_me_harder
and use FLOWI_FLAG_ANYSRC even for sockets. It looks safe
because the initial routing allowed this source address to
be used and now we just have to make sure the packet is rerouted.

	As a side effect this also allows rerouting for normal
raw sockets that use spoofed source addresses which was not possible
even before we eliminated the ip_route_input call.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07 22:52:32 -07:00
Daniel Baluta dd23198e58 ipv4: Fix ip_getsockopt for IP_PKTOPTIONS
IP_PKTOPTIONS is broken for 32-bit applications running
in COMPAT mode on 64-bit kernels.

This happens because msghdr's msg_flags field is always
set to zero. When running in COMPAT mode this should be
set to MSG_CMSG_COMPAT instead.

Signed-off-by: Tiberiu Szocs-Mihai <tszocs@ixiacom.com>
Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07 22:31:07 -07:00
Julian Anastasov d547f727df ipv4: fix the reusing of routing cache entries
compare_keys and ip_route_input_common rely on
rt_oif for distinguishing of input and output routes
with same keys values. But sometimes the input route has
also same hash chain (keyed by iif != 0) with the output
routes (keyed by orig_oif=0). Problem visible if running
with small number of rhash_entries.

	Fix them to use rt_route_iif instead. By this way
input route can not be returned to users that request
output route.

	The patch fixes the ip_rt_bug errors that were
reported in ip_local_out context, mostly for 255.255.255.255
destinations.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07 22:20:20 -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
Eric Dumazet f2c31e32b3 net: fix NULL dereferences in check_peer_redir()
Gergely Kalman reported crashes in check_peer_redir().

It appears commit f39925dbde (ipv4: Cache learned redirect
information in inetpeer.) added a race, leading to possible NULL ptr
dereference.

Since we can now change dst neighbour, we should make sure a reader can
safely use a neighbour.

Add RCU protection to dst neighbour, and make sure check_peer_redir()
can be called safely by different cpus in parallel.

As neighbours are already freed after one RCU grace period, this patch
should not add typical RCU penalty (cache cold effects)

Many thanks to Gergely for providing a pretty report pointing to the
bug.

Reported-by: Gergely Kalman <synapse@hippy.csoma.elte.hu>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-03 03:34:12 -07:00
Stephen Hemminger a9b3cd7f32 rcu: convert uses of rcu_assign_pointer(x, NULL) to RCU_INIT_POINTER
When assigning a NULL value to an RCU protected pointer, no barrier
is needed. The rcu_assign_pointer, used to handle that but will soon
change to not handle the special case.

Convert all rcu_assign_pointer of NULL value.

//smpl
@@ expression P; @@

- rcu_assign_pointer(P, NULL)
+ RCU_INIT_POINTER(P, NULL)

// </smpl>

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-02 04:29:23 -07:00
Julia Lawall a1889c0d20 net: adjust array index
Convert array index from the loop bound to the loop index.

A simplified version of the semantic patch that fixes this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e1,e2,ar;
@@

for(e1 = 0; e1 < e2; e1++) { <...
  ar[
- e2
+ e1
  ]
  ...> }
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-01 02:27:21 -07:00
Linus Torvalds d5eab9152a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (32 commits)
  tg3: Remove 5719 jumbo frames and TSO blocks
  tg3: Break larger frags into 4k chunks for 5719
  tg3: Add tx BD budgeting code
  tg3: Consolidate code that calls tg3_tx_set_bd()
  tg3: Add partial fragment unmapping code
  tg3: Generalize tg3_skb_error_unmap()
  tg3: Remove short DMA check for 1st fragment
  tg3: Simplify tx bd assignments
  tg3: Reintroduce tg3_tx_ring_info
  ASIX: Use only 11 bits of header for data size
  ASIX: Simplify condition in rx_fixup()
  Fix cdc-phonet build
  bonding: reduce noise during init
  bonding: fix string comparison errors
  net: Audit drivers to identify those needing IFF_TX_SKB_SHARING cleared
  net: add IFF_SKB_TX_SHARED flag to priv_flags
  net: sock_sendmsg_nosec() is static
  forcedeth: fix vlans
  gianfar: fix bug caused by 87c288c6e9
  gro: Only reset frag0 when skb can be pulled
  ...
2011-07-28 05:58:19 -07:00
Arun Sharma 60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Zoltan Kiss b76d0789c9 IPv4: Send gratuitous ARP for secondary IP addresses also
If a device event generates gratuitous ARP messages, only primary
address is used for sending. This patch iterates through the whole
list. Tested with 2 IP addresses configuration on bonding interface.

Signed-off-by: Zoltan Kiss <schaman@sch.bme.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-25 16:16:00 -07:00
xeb@mail.ru 559fafb94a gre: fix improper error handling
Fix improper protocol err_handler, current implementation is fully
unapplicable and may cause kernel crash due to double kfree_skb.

Signed-off-by: Dmitry Kozlov <xeb@mail.ru>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-23 20:06:00 -07:00
Julian Anastasov b0fe4a3184 ipv4: use RT_TOS after some rt_tos conversions
rt_tos was changed to iph->tos but it must be filtered by RT_TOS

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-23 20:05:31 -07:00
David S. Miller 415b3334a2 icmp: Fix regression in nexthop resolution during replies.
icmp_route_lookup() uses the wrong flow parameters if the reverse
session route lookup isn't used.

So do not commit to the re-decoded flow until we actually make a
final decision to use a real route saved in 'rt2'.

Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-22 06:22:10 -07:00
Bill Sommerfeld d9be4f7a6f ipv4: Constrain UFO fragment sizes to multiples of 8 bytes
Because the ip fragment offset field counts 8-byte chunks, ip
fragments other than the last must contain a multiple of 8 bytes of
payload.  ip_ufo_append_data wasn't respecting this constraint and,
depending on the MTU and ip option sizes, could create malformed
non-final fragments.

Google-Bug-Id: 5009328
Signed-off-by: Bill Sommerfeld <wsommerfeld@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21 21:31:41 -07:00
Eric Dumazet 87c48fa3b4 ipv6: make fragment identifications less predictable
IPv6 fragment identification generation is way beyond what we use for
IPv4 : It uses a single generator. Its not scalable and allows DOS
attacks.

Now inetpeer is IPv6 aware, we can use it to provide a more secure and
scalable frag ident generator (per destination, instead of system wide)

This patch :
1) defines a new secure_ipv6_id() helper
2) extends inet_getid() to provide 32bit results
3) extends ipv6_select_ident() with a new dest parameter

Reported-by: Fernando Gont <fernando@gont.com.ar>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21 21:25:58 -07:00
Jiri Pirko 9fea03302a lro: do vlan cleanup
- remove useless vlan parameters and pointers

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21 13:47:54 -07:00
Jiri Pirko 0f7257281d lro: kill lro_vlan_hwaccel_receive_frags
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21 13:47:54 -07:00
Jiri Pirko 7756a96e19 lro: kill lro_vlan_hwaccel_receive_skb
no longer used

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21 13:47:54 -07:00
Eric Dumazet 5c74501f76 ipv4: save cpu cycles from check_leaf()
Compiler is not smart enough to avoid double BSWAP instructions in
ntohl(inet_make_mask(plen)).

Lets cache this value in struct leaf_info, (fill a hole on 64bit arches)

With route cache disabled, this saves ~2% of cpu in udpflood bench on
x86_64 machine.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-18 10:41:18 -07:00
David S. Miller d3aaeb38c4 net: Add ->neigh_lookup() operation to dst_ops
In the future dst entries will be neigh-less.  In that environment we
need to have an easy transition point for current users of
dst->neighbour outside of the packet output fast path.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-18 00:40:17 -07:00
David S. Miller 69cce1d140 net: Abstract dst->neighbour accesses behind helpers.
dst_{get,set}_neighbour()

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-17 23:11:35 -07:00
David S. Miller 8f40b161de neigh: Pass neighbour entry to output ops.
This will get us closer to being able to do "neigh stuff"
completely independent of the underlying dst_entry for
protocols (ipv4/ipv6) that wish to do so.

We will also be able to make dst entries neigh-less.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-17 23:11:17 -07:00
David S. Miller 542d4d685f neigh: Kill ndisc_ops->queue_xmit
It is always dev_queue_xmit().

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16 18:30:59 -07:00
David S. Miller b23b5455b6 neigh: Kill hh_cache->hh_output
It's just taking on one of two possible values, either
neigh_ops->output or dev_queue_xmit().  And this is purely depending
upon whether nud_state has NUD_CONNECTED set or not.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16 17:45:02 -07:00
David S. Miller 47ec132a40 neigh: Kill neigh_ops->hh_output
It's always dev_queue_xmit().

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16 17:39:57 -07:00
David S. Miller 05e3aa0949 net: Create and use new helper, neigh_output().
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16 17:26:00 -07:00
David S. Miller fec8292d9c ipv4: Use calculated 'neigh' instead of re-evaluating dst->neighbour
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16 14:25:54 -07:00
David S. Miller 6a7ebdf2fd Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	net/bluetooth/l2cap_core.c
2011-07-14 07:56:40 -07:00
David S. Miller f6b72b6217 net: Embed hh_cache inside of struct neighbour.
Now that there is a one-to-one correspondance between neighbour
and hh_cache entries, we no longer need:

1) dynamic allocation
2) attachment to dst->hh
3) refcounting

Initialization of the hh_cache entry is indicated by hh_len
being non-zero, and such initialization is always done with
the neighbour's lock held as a writer.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-14 07:53:20 -07:00
David Miller 3769cffb1c ipv4: Inline neigh binding.
Get rid of all of the useless and costly indirection
by doing the neigh hash table lookup directly inside
of the neighbour binding.

Rename from arp_bind_neighbour to rt_bind_neighbour.

Use new helpers {__,}ipv4_neigh_lookup()

In rt_bind_neighbour() get rid of useless tests which
are never true in the context this function is called,
namely dev is never NULL and the dst->neighbour is
always NULL.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-13 01:12:28 -07:00
Eric Dumazet 6d1a3e042f inetpeer: kill inet_putpeer race
We currently can free inetpeer entries too early :

[  782.636674] WARNING: kmemcheck: Caught 32-bit read from uninitialized memory (f130f44c)
[  782.636677] 1f7b13c100000000000000000000000002000000000000000000000000000000
[  782.636686]  i i i i u u u u i i i i u u u u i i i i u u u u u u u u u u u u
[  782.636694]                          ^
[  782.636696]
[  782.636698] Pid: 4638, comm: ssh Not tainted 3.0.0-rc5+ #270 Hewlett-Packard HP Compaq 6005 Pro SFF PC/3047h
[  782.636702] EIP: 0060:[<c13fefbb>] EFLAGS: 00010286 CPU: 0
[  782.636707] EIP is at inet_getpeer+0x25b/0x5a0
[  782.636709] EAX: 00000002 EBX: 00010080 ECX: f130f3c0 EDX: f0209d30
[  782.636711] ESI: 0000bc87 EDI: 0000ea60 EBP: f0209ddc ESP: c173134c
[  782.636712]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[  782.636714] CR0: 8005003b CR2: f0beca80 CR3: 30246000 CR4: 000006d0
[  782.636716] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[  782.636717] DR6: ffff4ff0 DR7: 00000400
[  782.636718]  [<c13fbf76>] rt_set_nexthop.clone.45+0x56/0x220
[  782.636722]  [<c13fc449>] __ip_route_output_key+0x309/0x860
[  782.636724]  [<c141dc54>] tcp_v4_connect+0x124/0x450
[  782.636728]  [<c142ce43>] inet_stream_connect+0xa3/0x270
[  782.636731]  [<c13a8da1>] sys_connect+0xa1/0xb0
[  782.636733]  [<c13a99dd>] sys_socketcall+0x25d/0x2a0
[  782.636736]  [<c149deb8>] sysenter_do_call+0x12/0x28
[  782.636738]  [<ffffffff>] 0xffffffff

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-11 20:25:04 -07:00
David S. Miller f610b74b14 ipv4: Use universal hash for ARP.
We need to make sure the multiplier is odd.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-11 01:37:28 -07:00
Eric Dumazet f03d78db65 net: refine {udp|tcp|sctp}_mem limits
Current tcp/udp/sctp global memory limits are not taking into account
hugepages allocations, and allow 50% of ram to be used by buffers of a
single protocol [ not counting space used by sockets / inodes ...]

Lets use nr_free_buffer_pages() and allow a default of 1/8 of kernel ram
per protocol, and a minimum of 128 pages.
Heavy duty machines sysadmins probably need to tweak limits anyway.


References: https://bugzilla.stlinux.com/show_bug.cgi?id=38032
Reported-by: starlight <starlight@binnacle.cx>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-07 00:27:05 -07:00
David S. Miller e12fe68ce3 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2011-07-05 23:23:37 -07:00
David S. Miller 595fc71baa ipv4: Add ip_defrag() agent IP_DEFRAG_AF_PACKET.
Elide the ICMP on frag queue timeouts unconditionally for
this user.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-05 22:34:52 -07:00
Marcus Meissner c349a528cd net: bind() fix error return on wrong address family
Hi,

Reinhard Max also pointed out that the error should EAFNOSUPPORT according
to POSIX.

The Linux manpages have it as EINVAL, some other OSes (Minix, HPUX, perhaps BSD) use
EAFNOSUPPORT. Windows uses WSAEFAULT according to MSDN.

Other protocols error values in their af bind() methods in current mainline git as far
as a brief look shows:
	EAFNOSUPPORT: atm, appletalk, l2tp, llc, phonet, rxrpc
	EINVAL: ax25, bluetooth, decnet, econet, ieee802154, iucv, netlink, netrom, packet, rds, rose, unix, x25,
	No check?: can/raw, ipv6/raw, irda, l2tp/l2tp_ip

Ciao, Marcus

Signed-off-by: Marcus Meissner <meissner@suse.de>
Cc: Reinhard Max <max@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-04 21:37:41 -07:00
Steffen Klassert b00897b881 xfrm4: Don't call icmp_send on local error
Calling icmp_send() on a local message size error leads to
an incorrect update of the path mtu. So use ip_local_error()
instead to notify the socket about the error.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01 17:33:19 -07:00
Steffen Klassert c146066ab8 ipv4: Don't use ufo handling on later transformed packets
We might call ip_ufo_append_data() for packets that will be IPsec
transformed later. This function should be used just for real
udp packets. So we check for rt->dst.header_len which is only
nonzero on IPsec handling and call ip_ufo_append_data() just
if rt->dst.header_len is zero.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01 17:33:19 -07:00
Joe Perches 4500ebf8d1 ipv4: Reduce switch/case indent
Make the case labels the same indent as the switch.

git diff -w shows no difference.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01 16:11:16 -07:00
Joe Perches 181b1e9ce1 netfilter: Reduce switch/case indent
Make the case labels the same indent as the switch.

git diff -w shows miscellaneous 80 column wrapping,
comment reflowing and a comment for a useless gcc
warning for an otherwise unused default: case.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01 16:11:15 -07:00
Joe Perches 1d67a51682 ipconfig: Reduce switch/case indent
Make the case labels the same indent as the switch.

git diff -w shows miscellaneous 80 column wrapping.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01 16:11:15 -07:00
Julian Anastasov ed6e4ef836 netfilter: Fix ip_route_me_harder triggering ip_rt_bug
Avoid creating input routes with ip_route_me_harder.
It does not work for locally generated packets. Instead,
restrict sockets to provide valid saddr for output route (or
unicast saddr for transparent proxy). For other traffic
allow saddr to be unicast or local but if callers forget
to check saddr type use 0 for the output route.

	The resulting handling should be:

- REJECT TCP:
	- in INPUT we can provide addr_type = RTN_LOCAL but
	better allow rejecting traffic delivered with
	local route (no IP address => use RTN_UNSPEC to
	allow also RTN_UNICAST).
	- FORWARD: RTN_UNSPEC => allow RTN_LOCAL/RTN_UNICAST
	saddr, add fix to ignore RTN_BROADCAST and RTN_MULTICAST
	- OUTPUT: RTN_UNSPEC

- NAT, mangle, ip_queue, nf_ip_reroute: RTN_UNSPEC in LOCAL_OUT

- IPVS:
	- use RTN_LOCAL in LOCAL_OUT and FORWARD after SNAT
	to restrict saddr to be local

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-29 05:47:32 -07:00
Steffen Klassert 353e5c9abd ipv4: Fix IPsec slowpath fragmentation problem
ip_append_data() builds packets based on the mtu from dst_mtu(rt->dst.path).
On IPsec the effective mtu is lower because we need to add the protocol
headers and trailers later when we do the IPsec transformations. So after
the IPsec transformations the packet might be too big, which leads to a
slowpath fragmentation then. This patch fixes this by building the packets
based on the lower IPsec mtu from dst_mtu(&rt->dst) and adapts the exthdr
handling to this.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-27 20:34:26 -07:00
Steffen Klassert 33f99dc7fd ipv4: Fix packet size calculation in __ip_append_data
Git commit 59104f06 (ip: take care of last fragment in ip_append_data)
added a check to see if we exceed the mtu when we add trailer_len.
However, the mtu is already subtracted by the trailer length when the
xfrm transfomation bundles are set up. So IPsec packets with mtu
size get fragmented, or if the DF bit is set the packets will not
be send even though they match the mtu perfectly fine. This patch
actually reverts commit 59104f06.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-27 20:34:25 -07:00
Xufeng Zhang 9cfaa8def1 udp/recvmsg: Clear MSG_TRUNC flag when starting over for a new packet
Consider this scenario: When the size of the first received udp packet
is bigger than the receive buffer, MSG_TRUNC bit is set in msg->msg_flags.
However, if checksum error happens and this is a blocking socket, it will
goto try_again loop to receive the next packet.  But if the size of the
next udp packet is smaller than receive buffer, MSG_TRUNC flag should not
be set, but because MSG_TRUNC bit is not cleared in msg->msg_flags before
receive the next packet, MSG_TRUNC is still set, which is wrong.

Fix this problem by clearing MSG_TRUNC flag when starting over for a
new packet.

Signed-off-by: Xufeng Zhang <xufeng.zhang@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21 22:34:27 -07:00
Paul Gortmaker 56f8a75c17 ip: introduce ip_is_fragment helper inline function
There are enough instances of this:

    iph->frag_off & htons(IP_MF | IP_OFFSET)

that a helper function is probably warranted.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21 20:33:34 -07:00