Commit Graph

397 Commits

Author SHA1 Message Date
David S. Miller 7ce5a27f2e Revert "net: Handle CHECKSUM_COMPLETE more adequately in pskb_trim_rcsum()."
This reverts commit 018c5bba05.

It causes regressions for people using chips driven by the sungem
driver.  Suspicion is that the skb->csum value isn't being adjusted
properly.

The change also has a bug in that if __pskb_trim() fails, we'll leave
a corruped skb->csum value in there.  We would really need to revert
it to it's original value in that case.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-02 17:26:05 -05:00
David S. Miller 018c5bba05 net: Handle CHECKSUM_COMPLETE more adequately in pskb_trim_rcsum().
Currently pskb_trim_rcsum() just balks on CHECKSUM_COMPLETE packets
and remarks them as CHECKSUM_NONE, forcing a software checksum
validation later.

We have all of the mechanics available to fixup the skb->csum value,
even for complicated fragmented packets, via the helpers
skb_checksum() and csum_sub().

So just use them.

Based upon a suggestion by Herbert Xu.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-15 21:11:16 -05:00
Jiri Pirko 6aafeef03b netfilter: push reasm skb through instead of original frag skbs
Pushing original fragments through causes several problems. For example
for matching, frags may not be matched correctly. Take following
example:

<example>
On HOSTA do:
ip6tables -I INPUT -p icmpv6 -j DROP
ip6tables -I INPUT -p icmpv6 -m icmp6 --icmpv6-type 128 -j ACCEPT

and on HOSTB you do:
ping6 HOSTA -s2000    (MTU is 1500)

Incoming echo requests will be filtered out on HOSTA. This issue does
not occur with smaller packets than MTU (where fragmentation does not happen)
</example>

As was discussed previously, the only correct solution seems to be to use
reassembled skb instead of separete frags. Doing this has positive side
effects in reducing sk_buff by one pointer (nfct_reasm) and also the reams
dances in ipvs and conntrack can be removed.

Future plan is to remove net/ipv6/netfilter/nf_conntrack_reasm.c
entirely and use code in net/ipv6/reassembly.c instead.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-11 00:19:35 -05:00
Mathias Krause bc32383cd6 net: skbuff - kernel-doc fixes
Use "@" to refer to parameters in the kernel-doc description. According
to Documentation/kernel-doc-nano-HOWTO.txt "&" shall be used to refer to
structures only.

Signed-off-by: Mathias Krause <mathias.krause@secunet.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-07 19:28:59 -05:00
Mathias Krause 0c7ddf36c2 net: move pskb_put() to core code
This function has usage beside IPsec so move it to the core skbuff code.
While doing so, give it some documentation and change its return type to
'unsigned char *' to be in line with skb_put().

Signed-off-by: Mathias Krause <mathias.krause@secunet.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-07 19:28:58 -05:00
Jason Wang f8e617e100 net: introduce skb_coalesce_rx_frag()
Sometimes we need to coalesce the rx frags to avoid frag list. One example is
virtio-net driver which tries to use small frags for both MTU sized packet and
GSO packet. So this patch introduce skb_coalesce_rx_frag() to do this.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Michael Dalton <mwdalton@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-04 20:03:52 -05:00
Daniel Borkmann 2817a336d4 net: skb_checksum: allow custom update/combine for walking skb
Currently, skb_checksum walks over 1) linearized, 2) frags[], and
3) frag_list data and calculats the one's complement, a 32 bit
result suitable for feeding into itself or csum_tcpudp_magic(),
but unsuitable for SCTP as we're calculating CRC32c there.

Hence, in order to not re-implement the very same function in
SCTP (and maybe other protocols) over and over again, use an
update() + combine() callback internally to allow for walking
over the skb with different algorithms.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-03 23:04:57 -05:00
Eric Dumazet 61c1db7fae ipv6: sit: add GSO/TSO support
Now ipv6_gso_segment() is stackable, its relatively easy to
implement GSO/TSO support for SIT tunnels

Performance results, when segmentation is done after tunnel
device (as no NIC is yet enabled for TSO SIT support) :

Before patch :

lpq84:~# ./netperf -H 2002:af6:1153:: -Cc
MIGRATED TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to 2002:af6:1153:: () port 0 AF_INET6
Recv   Send    Send                          Utilization       Service Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local   remote
bytes  bytes   bytes    secs.    10^6bits/s  % S      % S      us/KB   us/KB

 87380  16384  16384    10.00      3168.31   4.81     4.64     2.988   2.877

After patch :

lpq84:~# ./netperf -H 2002:af6:1153:: -Cc
MIGRATED TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to 2002:af6:1153:: () port 0 AF_INET6
Recv   Send    Send                          Utilization       Service Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local   remote
bytes  bytes   bytes    secs.    10^6bits/s  % S      % S      us/KB   us/KB

 87380  16384  16384    10.00      5525.00   7.76     5.17     2.763   1.840

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-21 18:49:39 -04:00
Eric Dumazet cb32f511a7 ipip: add GSO/TSO support
Now inet_gso_segment() is stackable, its relatively easy to
implement GSO/TSO support for IPIP

Performance results, when segmentation is done after tunnel
device (as no NIC is yet enabled for TSO IPIP support) :

Before patch :

lpq83:~# ./netperf -H 7.7.9.84 -Cc
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.9.84 () port 0 AF_INET
Recv   Send    Send                          Utilization       Service Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local   remote
bytes  bytes   bytes    secs.    10^6bits/s  % S      % S      us/KB   us/KB

 87380  16384  16384    10.00      3357.88   5.09     3.70     2.983   2.167

After patch :

lpq83:~# ./netperf -H 7.7.9.84 -Cc
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.9.84 () port 0 AF_INET
Recv   Send    Send                          Utilization       Service Demand
Socket Socket  Message  Elapsed              Send     Recv     Send    Recv
Size   Size    Size     Time     Throughput  local    remote   local   remote
bytes  bytes   bytes    secs.    10^6bits/s  % S      % S      us/KB   us/KB

 87380  16384  16384    10.00      7710.19   4.52     6.62     1.152   1.687

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-19 19:36:19 -04:00
Eric Dumazet 3347c96029 ipv4: gso: make inet_gso_segment() stackable
In order to support GSO on IPIP, we need to make
inet_gso_segment() stackable.

It should not assume network header starts right after mac
header.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-19 19:36:18 -04:00
Eric Dumazet 400dfd3ae8 net: refactor sk_page_frag_refill()
While working on virtio_net new allocation strategy to increase
payload/truesize ratio, we found that refactoring sk_page_frag_refill()
was needed.

This patch splits sk_page_frag_refill() into two parts, adding
skb_page_frag_refill() which can be used without a socket.

While we are at it, add a minimum frag size of 32 for
sk_page_frag_refill()

Michael will either use netdev_alloc_frag() from softirq context,
or skb_page_frag_refill() from process context in refill_work()
 (GFP_KERNEL allocations)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18 00:08:51 -04:00
Denis Kirjanov 0b3d8e087b include/linux/skbuff.h: move CONFIG_XFRM check inside the skb_sec_path()
And thus we have only one function definition

Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-02 16:50:40 -04:00
David S. Miller 4fbef95af4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/emulex/benet/be.h
	drivers/net/usb/qmi_wwan.c
	drivers/net/wireless/brcm80211/brcmfmac/dhd_bus.h
	include/net/netfilter/nf_conntrack_synproxy.h
	include/net/secure_seq.h

The conflicts are of two varieties:

1) Conflicts with Joe Perches's 'extern' removal from header file
   function declarations.  Usually it's an argument signature change
   or a function being added/removed.  The resolutions are trivial.

2) Some overlapping changes in qmi_wwan.c and be.h, one commit adds
   a new value, another changes an existing value.  That sort of
   thing.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-01 17:06:14 -04:00
Nicolas Dichtel 4590672357 skbuff: size of hole is wrong in a comment
Since commit c93bdd0e03 ("netvm: allow skb allocation to use PFMEMALLOC
reserves"), hole size is one bit less than what is written in the comment.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-30 22:32:39 -07:00
Eric Dumazet 36a8f39e05 net: skb_is_gso_v6() requires skb_is_gso()
bnx2x makes a dangerous use of skb_is_gso_v6().

It should first make sure skb is a gso packet

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eilon Greenstein <eilong@broadcom.com>
Acked-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-30 22:09:00 -07:00
Joe Perches 7965bd4d71 net.h/skbuff.h: Remove extern from function prototypes
There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: Joe Perches <joe@perches.com>
2013-09-26 14:53:19 -07:00
Nicolas Dichtel 8b27f27797 skb: allow skb_scrub_packet() to be used by tunnels
This function was only used when a packet was sent to another netns. Now, it can
also be used after tunnel encapsulation or decapsulation.

Only skb_orphan() should not be done when a packet is not crossing netns.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04 00:27:25 -04:00
Florian Fainelli bc6fc9fa0e net: fix comment typo for __skb_alloc_pages()
The name of the function in the comment is __skb_alloc_page() while we
are actually commenting __skb_alloc_pages(). Fix this typo and make it
a valid kernel doc comment.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03 22:17:40 -04:00
Jason Wang c3bdeb5c7c net: move zerocopy_sg_from_iovec() to net/core/datagram.c
To let it be reused and reduce code duplication. Also document this function.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-07 16:52:34 -07:00
David S. Miller 0e76a3a587 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge net into net-next to setup some infrastructure Eric
Dumazet needs for usbnet changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-03 21:36:46 -07:00
Cong Wang e0d1095ae3 net: rename CONFIG_NET_LL_RX_POLL to CONFIG_NET_RX_BUSY_POLL
Eliezer renames several *ll_poll to *busy_poll, but forgets
CONFIG_NET_LL_RX_POLL, so in case of confusion, rename it too.

Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-01 15:11:17 -07:00
Eric Dumazet 376c7311bd net: add a temporary sanity check in skb_orphan()
David suggested to add a BUG_ON() to catch if some layer
sets skb->sk pointer without a corresponding destructor.

As skb can sit in a queue, it's mandatory to make sure the
socket cannot disappear, and it's usually done by taking a
reference on the socket, then releasing it from the skb
destructor.

This patch is a follow-up to commit c34a761231
("net: skb_orphan() changes") and will be reverted after
catching all possible offenders if any.

Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-01 12:49:28 -07:00
Eric Dumazet c34a761231 net: skb_orphan() changes
It is illegal to set skb->sk without corresponding destructor.

Its therefore safe for skb_orphan() to not clear skb->sk if
skb->destructor is not set.

Also avoid clearing skb->destructor if already NULL.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-31 15:24:08 -07:00
David S. Miller 0c1072ae02 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/freescale/fec_main.c
	drivers/net/ethernet/renesas/sh_eth.c
	net/ipv4/gre.c

The GRE conflict is between a bug fix (kfree_skb --> kfree_skb_list)
and the splitting of the gre.c code into seperate files.

The FEC conflict was two sets of changes adding ethtool support code
in an "!CONFIG_M5272" CPP protected block.

Finally the sh_eth.c conflict was between one commit add bits set
in the .eesr_err_check mask whilst another commit removed the
.tx_error_check member and assignments.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-03 14:55:13 -07:00
Nicolas Dichtel 621e84d6f3 dev: introduce skb_scrub_packet()
The goal of this new function is to perform all needed cleanup before sending
an skb into another netns.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-27 22:29:05 -07:00
Eric Dumazet bd8a7036c0 gre: fix a possible skb leak
commit 68c3316311 ("v4 GRE: Add TCP segmentation offload for GRE")
added a possible skb leak, because it frees only the head of segment
list, in case a skb_linearize() call fails.

This patch adds a kfree_skb_list() helper to fix the bug.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-25 16:07:44 -07:00
Cong Wang 30f3a40f9a net: remove last caller of skb_tail_offset() and itself
Similar to the following commits:

commit 00f97da17a (netpoll: fix position of network header)
commit 525cebedb3 (pktgen: Fix position of ip and udp header)

using skb_tail_offset() seems not correct since the offset
is based on head pointer.

With the last caller removed, skb_tail_offset() can be killed
finally.

Cc: Thomas Graf <tgraf@suug.ch>
Cc: Daniel Borkmann <dborkmann@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-10 22:22:23 -07:00
Eliezer Tamir 0602129286 net: add low latency socket poll
Adds an ndo_ll_poll method and the code that supports it.
This method can be used by low latency applications to busy-poll
Ethernet device queues directly from the socket code.
sysctl_net_ll_poll controls how many microseconds to poll.
Default is zero (disabled).
Individual protocol support will be added by subsequent patches.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-10 21:22:35 -07:00
David S. Miller 6bc19fb82d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge 'net' bug fixes into 'net-next' as we have patches
that will build on top of them.

This merge commit includes a change from Emil Goode
(emilgoode@gmail.com) that fixes a warning that would
have been introduced by this merge.  Specifically it
fixes the pingv6_ops method ipv6_chk_addr() to add a
"const" to the "struct net_device *dev" argument and
likewise update the dummy_ipv6_chk_addr() declaration.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-05 16:37:30 -07:00
Pravin B Shelar 1e2bd517c1 udp6: Fix udp fragmentation for tunnel traffic.
udp6 over GRE tunnel does not work after to GRE tso changes. GRE
tso handler passes inner packet but keeps track of outer header
start in SKB_GSO_CB(skb)->mac_offset.  udp6 fragment need to
take care of outer header, which start at the mac_offset, while
adding fragment header.
This bug is introduced by commit 68c3316311 (GRE: Add TCP
segmentation offload for GRE).

Reported-by: Dmitry Kravkov <dkravkov@gmail.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Tested-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-31 17:06:07 -07:00
Cong Wang 35d0461061 net: clean up skb headers code
commit 1a37e412a0 (net: Use 16bits for *_headers
fields of struct skbuff) converts skb->*_header to u16,
some #if NET_SKBUFF_DATA_USES_OFFSET are now useless,
and to be safe, we could just use "X = (typeof(X)) ~0U;"
as suggested by David.

Cc: David S. Miller <davem@davemloft.net>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-31 17:02:47 -07:00
Simon Horman 7cc4619005 net, ipv4, ipv6: Correct assignment of skb->network_header to skb->tail
This corrects an regression introduced by "net: Use 16bits for *_headers
fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In
that case skb->tail will be a pointer however skb->network_header is now
an offset.

This patch corrects the problem by adding a wrapper to return skb tail as
an offset regardless of the value of NET_SKBUFF_DATA_USES_OFFSET. It seems
that skb->tail that this offset may be more than 64k and some care has been
taken to treat such cases as an error.

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-28 23:49:07 -07:00
Simon Horman 0d89d2035f MPLS: Add limited GSO support
In the case where a non-MPLS packet is received and an MPLS stack is
added it may well be the case that the original skb is GSO but the
NIC used for transmit does not support GSO of MPLS packets.

The aim of this code is to provide GSO in software for MPLS packets
whose skbs are GSO.

SKB Usage:

When an implementation adds an MPLS stack to a non-MPLS packet it should do
the following to skb metadata:

* Set skb->inner_protocol to the old non-MPLS ethertype of the packet.
  skb->inner_protocol is added by this patch.

* Set skb->protocol to the new MPLS ethertype of the packet.

* Set skb->network_header to correspond to the
  end of the L3 header, including the MPLS label stack.

I have posted a patch, "[PATCH v3.29] datapath: Add basic MPLS support to
kernel" which adds MPLS support to the kernel datapath of Open vSwtich.
That patch sets the above requirements in datapath/actions.c:push_mpls()
and was used to exercise this code.  The datapath patch is against the Open
vSwtich tree but it is intended that it be added to the Open vSwtich code
present in the mainline Linux kernel at some point.

Features:

I believe that the approach that I have taken is at least partially
consistent with the handling of other protocols.  Jesse, I understand that
you have some ideas here.  I am more than happy to change my implementation.

This patch adds dev->mpls_features which may be used by devices
to advertise features supported for MPLS packets.

A new NETIF_F_MPLS_GSO feature is added for devices which support
hardware MPLS GSO offload.  Currently no devices support this
and MPLS GSO always falls back to software.

Alternate Implementation:

One possible alternate implementation is to teach netif_skb_features()
and skb_network_protocol() about MPLS, in a similar way to their
understanding of VLANs. I believe this would avoid the need
for net/mpls/mpls_gso.c and in particular the calls to
__skb_push() and __skb_push() in mpls_gso_segment().

I have decided on the implementation in this patch as it should
not introduce any overhead in the case where mpls_gso is not compiled
into the kernel or inserted as a module.

MPLS GSO suggested by Jesse Gross.
Based in part on "v4 GRE: Add TCP segmentation offload for GRE"
by Pravin B Shelar.

Cc: Jesse Gross <jesse@nicira.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-27 22:50:59 -07:00
Simon Horman 1a37e412a0 net: Use 16bits for *_headers fields of struct skbuff
In order to mitigate ongoing incresase in the size of struct skbuff
use 16 bit integer offsets rather than pointers for inner_*_headers.

This appears to reduce the size of struct skbuff from 0xd0 to 0xc0
bytes on x86_64 with the following all unset.

	CONFIG_XFRM
	CONFIG_NF_CONNTRACK
	CONFIG_NF_CONNTRACK_MODULE
	NET_SKBUFF_NF_DEFRAG_NEEDED
	CONFIG_BRIDGE_NETFILTER
	CONFIG_NET_SCHED
	CONFIG_IPV6_NDISC_NODETYPE
	CONFIG_NET_DMA
	CONFIG_NETWORK_SECMARK

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-27 22:50:59 -07:00
Patrick McHardy 0ebd0ac5ff net: add function to allocate sk_buff head without data area
Add a function to allocate a sk_buff head without any data. This will
be used by memory mapped netlink to attach data from the mmaped area
to the skb.

Additionally change skb_release_all() to check whether the skb has a
data area to allow the skb destructor to clear the data pointer in case
only a head has been allocated.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19 14:57:57 -04:00
Patrick McHardy 86a9bad3ab net: vlan: add protocol argument to packet tagging functions
Add a protocol argument to the VLAN packet tagging functions. In case of HW
tagging, we need that protocol available in the ndo_start_xmit functions,
so it is stored in a new field in the skb. The new field fits into a hole
(on 64 bit) and doesn't increase the sks's size.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19 14:46:06 -04:00
David S. Miller d978a6361a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/nfc/microread/mei.c
	net/netfilter/nfnetlink_queue_core.c

Pull in 'net' to get Eric Biederman's AF_UNIX fix, upon which
some cleanups are going to go on-top.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-07 18:37:01 -04:00
Patrick McHardy 124dff01af netfilter: don't reset nf_trace in nf_reset()
Commit 130549fe ("netfilter: reset nf_trace in nf_reset") added code
to reset nf_trace in nf_reset(). This is wrong and unnecessary.

nf_reset() is used in the following cases:

- when passing packets up the the socket layer, at which point we want to
  release all netfilter references that might keep modules pinned while
  the packet is queued. nf_trace doesn't matter anymore at this point.

- when encapsulating or decapsulating IPsec packets. We want to continue
  tracing these packets after IPsec processing.

- when passing packets through virtual network devices. Only devices on
  that encapsulate in IPv4/v6 matter since otherwise nf_trace is not
  used anymore. Its not entirely clear whether those packets should
  be traced after that, however we've always done that.

- when passing packets through virtual network devices that make the
  packet cross network namespace boundaries. This is the only cases
  where we clearly want to reset nf_trace and is also what the
  original patch intended to fix.

Add a new function nf_reset_trace() and use it in dev_forward_skb() to
fix this properly.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-05 15:38:10 -04:00
Julian Anastasov 932bc4d7a5 net: add skb_dst_set_noref_force
Rename skb_dst_set_noref to __skb_dst_set_noref and
add force flag as suggested by David Miller. The new wrapper
skb_dst_set_noref_force will force dst entries that are not
cached to be attached as skb dst without taking reference
as long as provided dst is reclaimed after RCU grace period.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off by: Hans Schillstrom <hans@schillstrom.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Simon Horman <horms@verge.net.au>
2013-04-02 00:22:53 +02:00
Ying Xue fbbdb8f096 net: fix compile error of implicit declaration of skb_probe_transport_header
The commit 40893fd(net: switch to use skb_probe_transport_header())
involes a new error accidently. When NET_SKBUFF_DATA_USES_OFFSE is
not enabled, below compile error happens:

  CC      net/packet/af_packet.o
  net/packet/af_packet.c: In function ‘packet_sendmsg_spkt’:
  net/packet/af_packet.c:1516:2: error: implicit declaration of function ‘skb_probe_transport_header’ [-Werror=implicit-function-declaration]
  cc1: some warnings being treated as errors
  make[2]: *** [net/packet/af_packet.o] Error 1
  make[1]: *** [net/packet] Error 2
  make: *** [net] Error 2

As it seems skb_probe_transport_header() is not related to
NET_SKBUFF_DATA_USES_OFFSE, we should move the definition of
skb_probe_transport_header() out of scope of
NET_SKBUFF_DATA_USES_OFFSE macro.

Cc: Jason Wang <jasowang@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-27 23:21:58 -04:00
Jason Wang 5203cd28db net: core: introduce skb_probe_transport_header()
Sometimes, we need probe and set the transport header for packets (e.g from
untrusted source). This patch introduces a new helper
skb_probe_transport_header() which tries to probe and set the l4 header through
skb_flow_dissect(), if not just set the transport header to the hint passed by
caller.

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-27 12:48:31 -04:00
Gao feng 130549fed8 netfilter: reset nf_trace in nf_reset
We forgot to clear the nf_trace of sk_buff in nf_reset,
When we use veth device, this nf_trace information will
be leaked from one net namespace to another net namespace.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-03-25 14:21:23 +01:00
Daniel Borkmann f77668dc25 net: flow_dissector: add __skb_get_poff to get a start offset to payload
__skb_get_poff() returns the offset to the payload as far as it could
be dissected. The main user is currently BPF, so that we can dynamically
truncate packets without needing to push actual payload to the user
space and instead can analyze headers only.

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-20 13:15:45 -04:00
David S. Miller 61816596d1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull in the 'net' tree to get Daniel Borkmann's flow dissector
infrastructure change.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-20 12:46:26 -04:00
Pavel Emelyanov cca7af3889 skb: Propagate pfmemalloc on skb from head page only
Hi.

I'm trying to send big chunks of memory from application address space via
TCP socket using vmsplice + splice like this

   mem = mmap(128Mb);
   vmsplice(pipe[1], mem); /* splice memory into pipe */
   splice(pipe[0], tcp_socket); /* send it into network */

When I'm lucky and a huge page splices into the pipe and then into the socket
_and_ client and server ends of the TCP connection are on the same host,
communicating via lo, the whole connection gets stuck! The sending queue
becomes full and app stops writing/splicing more into it, but the receiving
queue remains empty, and that's why.

The __skb_fill_page_desc observes a tail page of a huge page and erroneously
propagates its page->pfmemalloc value onto socket (the pfmemalloc on tail pages
contain garbage). Then this skb->pfmemalloc leaks through lo and due to the

    tcp_v4_rcv
    sk_filter
        if (skb->pfmemalloc && !sock_flag(sk, SOCK_MEMALLOC)) /* true */
            return -ENOMEM
        goto release_and_discard;

no packets reach the socket. Even TCP re-transmits are dropped by this, as skb
cloning clones the pfmemalloc flag as well.

That said, here's the proper page->pfmemalloc propagation onto socket: we
must check the huge-page's head page only, other pages' pfmemalloc and mapping
values do not contain what is expected in this place. However, I'm not sure
whether this fix is _complete_, since pfmemalloc propagation via lo also
oesn't look great.

Both, bit propagation from page to skb and this check in sk_filter, were
introduced by c48a11c7 (netvm: propagate page->pfmemalloc to skb), in v3.5 so
Mel and stable@ are in Cc.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-14 11:53:32 -04:00
Eric Dumazet 16fad69cfe tcp: fix skb_availroom()
Chrome OS team reported a crash on a Pixel ChromeBook in TCP stack :

https://code.google.com/p/chromium/issues/detail?id=182056

commit a21d45726a (tcp: avoid order-1 allocations on wifi and tx
path) did a poor choice adding an 'avail_size' field to skb, while
what we really needed was a 'reserved_tailroom' one.

It would have avoided commit 22b4a4f22d (tcp: fix retransmit of
partially acked frames) and this commit.

Crash occurs because skb_split() is not aware of the 'avail_size'
management (and should not be aware)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Mukesh Agrawal <quiche@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-14 11:49:45 -04:00
Pravin B Shelar 7313626745 tunneling: Add generic Tunnel segmentation.
Adds generic tunneling offloading support for IPv4-UDP based
tunnels.
GSO type is added to request this offload for a skb.
netdev feature NETIF_F_UDP_TUNNEL is added for hardware offloaded
udp-tunnel support. Currently no device supports this feature,
software offload is used.

This can be used by tunneling protocols like VXLAN.

CC: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-09 16:09:17 -05:00
Pravin B Shelar aefbd2b3c2 tunneling: Capture inner mac header during encapsulation.
This patch adds inner mac header. This will be used in next patch
to find tunner header length. Header len is required to copy tunnel
header to each gso segment.
This patch does not change any functionality.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-09 16:08:57 -05:00
Pravin B Shelar 68c3316311 v4 GRE: Add TCP segmentation offload for GRE
Following patch adds GRE protocol offload handler so that
skb_gso_segment() can segment GRE packets.
SKB GSO CB is added to keep track of total header length so that
skb_segment can push entire header. e.g. in case of GRE, skb_segment
need to push inner and outer headers to every segment.
New NETIF_F_GRE_GSO feature is added for devices which support HW
GRE TSO offload. Currently none of devices support it therefore GRE GSO
always fall backs to software GSO.

[ Compute pkt_len before ip_local_out() invocation. -DaveM ]

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-15 15:17:11 -05:00
Pravin B Shelar 14bbd6a565 net: Add skb_unclone() helper function.
This function will be used in next GRE_GSO patch. This patch does
not change any functionality.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Eric Dumazet <edumazet@google.com>
2013-02-15 15:10:37 -05:00