Commit Graph

175 Commits

Author SHA1 Message Date
Eric Dumazet
abc4e4fa29 packet: dont drop packet but consume it
When we need to clone skb, we dont drop a packet.
Call consume_skb() to not confuse dropwatch.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-19 14:23:55 -04:00
Eric Dumazet
95c9617472 net: cleanup unsigned to unsigned int
Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15 12:44:40 -04:00
David Howells
9ffc93f203 Remove all #inclusions of asm/system.h
Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`

Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-28 18:30:03 +01:00
Ben Greear
3bdc0eba0b net: Add framework to allow sending packets with customized CRC.
This is useful for testing RX handling of frames with bad
CRCs.

Requires driver support to actually put the packet on the
wire properly.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2012-02-24 01:37:35 -08:00
David S. Miller
7f8e3234c5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2011-12-30 13:04:14 -05:00
Wei Yongjun
aef950b4ba packet: fix possible dev refcnt leak when bind fail
If bind is fail when bind is called after set PACKET_FANOUT
sock option, the dev refcnt will leak.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-27 22:32:41 -05:00
David S. Miller
abb434cb05 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/bluetooth/l2cap_core.c

Just two overlapping changes, one added an initialization of
a local variable, and another change added a new local variable.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-23 17:13:56 -05:00
Eric Dumazet
0fd7bac6b6 net: relax rcvbuf limits
skb->truesize might be big even for a small packet.

Its even bigger after commit 87fb4b7b53 (net: more accurate skb
truesize) and big MTU.

We should allow queueing at least one packet per receiver, even with a
low RCVBUF setting.

Reported-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-23 02:15:14 -05:00
Herbert Xu
4ce4091256 packet: Add needed_tailroom to packet_sendmsg_spkt
packet: Add needed_tailroom to packet_sendmsg_spkt

While auditing LL_ALLOCATED_SPACE I noticed that packet_sendmsg_spkt
did not include needed_tailroom when allocating an skb.  This isn't
a fatal error as we should always tolerate inadequate tail room but
it isn't optimal.

This patch fixes that.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-18 14:37:10 -05:00
Herbert Xu
ae641949df net: Remove all uses of LL_ALLOCATED_SPACE
net: Remove all uses of LL_ALLOCATED_SPACE

The macro LL_ALLOCATED_SPACE was ill-conceived.  It applies the
alignment to the sum of needed_headroom and needed_tailroom.  As
the amount that is then reserved for head room is needed_headroom
with alignment, this means that the tail room left may be too small.

This patch replaces all uses of LL_ALLOCATED_SPACE with the macro
LL_RESERVED_SPACE and direct reference to needed_tailroom.

This also fixes the problem with needed_headroom changing between
allocating the skb and reserving the head room.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-18 14:37:09 -05:00
Olof Johansson
eea49cc900 af_packet: de-inline some helper functions
This popped some compiler errors due to mismatched prototypes. Just
remove most manual inlines, the compiler should be able to figure out
what makes sense to inline and not.

net/packet/af_packet.c:252: warning: 'prb_curr_blk_in_use' declared inline after being called
net/packet/af_packet.c:252: warning: previous declaration of 'prb_curr_blk_in_use' was here
net/packet/af_packet.c:258: warning: 'prb_queue_frozen' declared inline after being called
net/packet/af_packet.c:258: warning: previous declaration of 'prb_queue_frozen' was here
net/packet/af_packet.c:248: warning: 'packet_previous_frame' declared inline after being called
net/packet/af_packet.c:248: warning: previous declaration of 'packet_previous_frame' was here
net/packet/af_packet.c:251: warning: 'packet_increment_head' declared inline after being called
net/packet/af_packet.c:251: warning: previous declaration of 'packet_increment_head' was here

Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: Chetan Loke <loke.chetan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-03 18:11:51 -04:00
Eric Dumazet
bc416d9768 macvlan: handle fragmented multicast frames
Fragmented multicast frames are delivered to a single macvlan port,
because ip defrag logic considers other samples are redundant.

Implement a defrag step before trying to send the multicast frame.

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-18 23:22:07 -04:00
danborkmann@iogearbox.net
95f5f803b3 af_packet: remove unnecessary BUG_ON() in tpacket_destruct_skb
If skb is NULL, then stack trace is thrown anyway on dereference.
Therefore, the stack trace triggered by BUG_ON is duplicate.

Signed-off-by: Daniel Borkmann <danborkmann@googlemail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-10 14:09:08 -04:00
David S. Miller
88c5100c28 Merge branch 'master' of github.com:davem330/net
Conflicts:
	net/batman-adv/soft-interface.c
2011-10-07 13:38:43 -04:00
Willem de Bruijn
7091fbd82c make PACKET_STATISTICS getsockopt report consistently between ring and non-ring
This is a minor change.

Up until kernel 2.6.32, getsockopt(fd, SOL_PACKET, PACKET_STATISTICS,
...) would return total and dropped packets since its last invocation. The
introduction of socket queue overflow reporting [1] changed drop
rate calculation in the normal packet socket path, but not when using a
packet ring. As a result, the getsockopt now returns different statistics
depending on the reception method used. With a ring, it still returns the
count since the last call, as counts are incremented in tpacket_rcv and
reset in getsockopt. Without a ring, it returns 0 if no drops occurred
since the last getsockopt and the total drops over the lifespan of
the socket otherwise. The culprit is this line in packet_rcv, executed
on a drop:

drop_n_acct:
        po->stats.tp_drops = atomic_inc_return(&sk->sk_drops);

As it shows, the new drop number it taken from the socket drop counter,
which is not reset at getsockopt. I put together a small example
that demonstrates the issue [2]. It runs for 10 seconds and overflows
the queue/ring on every odd second. The reported drop rates are:
ring: 16, 0, 16, 0, 16, ...
non-ring: 0, 15, 0, 30, 0, 46, 0, 60, 0 , 74.

Note how the even ring counts monotonically increase. Because the
getsockopt adds tp_drops to tp_packets, total counts are similarly
reported cumulatively. Long story short, reinstating the original code, as
the below patch does, fixes the issue at the cost of additional per-packet
cycles. Another solution that does not introduce per-packet overhead
is be to keep the current data path, record the value of sk_drops at
getsockopt() at call N in a new field in struct packetsock and subtract
that when reporting at call N+1. I'll be happy to code that, instead,
it's just more messy.

[1] http://patchwork.ozlabs.org/patch/35665/
[2] http://kernel.googlecode.com/files/test-packetsock-getstatistics.c

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03 14:18:26 -04:00
Jiri Pirko
4bc71cb983 net: consolidate and fix ethtool_ops->get_settings calling
This patch does several things:
- introduces __ethtool_get_settings which is called from ethtool code and
  from drivers as well. Put ASSERT_RTNL there.
- dev_ethtool_get_settings() is replaced by __ethtool_get_settings()
- changes calling in drivers so rtnl locking is respected. In
  iboe_get_rate was previously ->get_settings() called unlocked. This
  fixes it. Also prb_calc_retire_blk_tmo() in af_packet.c had the same
  problem. Also fixed by calling __dev_get_by_index() instead of
  dev_get_by_index() and holding rtnl_lock for both calls.
- introduces rtnl_lock in bnx2fc_vport_create() and fcoe_vport_create()
  so bnx2fc_if_create() and fcoe_if_create() are called locked as they
  are from other places.
- use __ethtool_get_settings() in bonding code

Signed-off-by: Jiri Pirko <jpirko@redhat.com>

v2->v3:
	-removed dev_ethtool_get_settings()
	-added ASSERT_RTNL into __ethtool_get_settings()
	-prb_calc_retire_blk_tmo - use __dev_get_by_index() and lock
	 around it and __ethtool_get_settings() call
v1->v2:
        add missing export_symbol
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> [except FCoE bits]
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-15 17:32:26 -04:00
chetan loke
bc59ba3991 af_packet: Prefixed tpacket_v3 structs to avoid name space collision
structs introduced in tpacket_v3 implementation are prefixed with 'tpacket'
to avoid namespace collision.

Compile tested.

Signed-off-by: Chetan Loke <loke.chetan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-26 12:38:44 -04:00
chetan loke
f6fb8f100b af-packet: TPACKET_V3 flexible buffer implementation.
1) Blocks can be configured with non-static frame-size.
2) Read/poll is at a block-level(as opposed to packet-level).
3) Added poll timeout to avoid indefinite user-space wait on idle links.
4) Added user-configurable knobs:
   4.1) block::timeout.
   4.2) tpkt_hdr::sk_rxhash.

Changes:
C1) tpacket_rcv()
    C1.1) packet_current_frame() is replaced by packet_current_rx_frame()
          The bulk of the processing is then moved in the following chain:
          packet_current_rx_frame()
            __packet_lookup_frame_in_block
              fill_curr_block()
              or
                retire_current_block
                dispatch_next_block
              or
              return NULL(queue is plugged/paused)

Signed-off-by: Chetan Loke <loke.chetan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-24 19:40:40 -07:00
Chetan Loke
cc9f01b246 af-packet: fix - avoid reading stale data
Currently we flush tp_status and then flush the remainder of the header+payload.
tp_status should be flushed in the end to avoid stale data being read by user-space.

Incorrectly re-ordered barriers in v1.

Signed-off-by: Chetan Loke <loke.chetan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-14 08:36:33 -07:00
David S. Miller
31817df025 packet: Fix build with INET disabled.
af_packet.c:(.text+0x3d130): undefined reference to `ip_defrag'
or
ERROR: "ip_defrag" [net/packet/af_packet.ko] undefined!

Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-07 08:18:04 -07:00
Eric Dumazet
afe62c68cd af_packet: lock imbalance
fanout_add() might return with fanout_mutex held.

Reduce indentation level while we are at it

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-07 06:41:29 -07:00
David S. Miller
aec27311c2 packet: Fix leak in pre-defrag support.
When we clone the SKB, we forget about the original
one.  Avoid this problem by using skb_share_check().

Reported-by: Penttilä Mika <mika.penttila@ixonos.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-06 07:30:59 -07:00
David S. Miller
95ec3eb417 packet: Add 'cpu' fanout policy.
Unfortunately we have to use a real modulus here as
the multiply trick won't work as effectively with cpu
numbers as it does with rxhash values.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-06 01:56:38 -07:00
David S. Miller
7736d33f42 packet: Add pre-defragmentation support for ipv4 fanouts.
The skb->rxhash cannot be properly computed if the
packet is a fragment.  To alleviate this, allow the
AF_PACKET client to ask for defragmentation to be
done at demux time.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-05 22:34:52 -07:00
David S. Miller
dc99f60069 packet: Add fanout support.
Fanouts allow packet capturing to be demuxed to a set of AF_PACKET
sockets.  Two fanout policies are implemented:

1) Hashing based upon skb->rxhash

2) Pure round-robin

An AF_PACKET socket must be fully bound before it tries to add itself
to a fanout.  All AF_PACKET sockets trying to join the same fanout
must all have the same bind settings.

Fanouts are identified (within a network namespace) by a 16-bit ID.
The first socket to try to add itself to a fanout with a particular
ID, creates that fanout.  When the last socket leaves the fanout
(which happens only when the socket is closed), that fanout is
destroyed.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-05 22:34:52 -07:00
David S. Miller
ce06b03e60 packet: Add helpers to register/unregister ->prot_hook
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-05 22:34:52 -07:00
David S. Miller
9f6ec8d697 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
	drivers/net/wireless/rtlwifi/pci.c
	net/netfilter/ipvs/ip_vs_core.c
2011-06-20 22:29:08 -07:00
Jason Wang
10a8d94a95 virtio_net: introduce VIRTIO_NET_HDR_F_DATA_VALID
There's no need for the guest to validate the checksum if it have been
validated by host nics. So this patch introduces a new flag -
VIRTIO_NET_HDR_F_DATA_VALID which is used to bypass the checksum
examing in guest. The backend (tap/macvtap) may set this flag when
met skbs with CHECKSUM_UNNECESSARY to save cpu utilization.

No feature negotiation is needed as old driver just ignore this flag.

Iperf shows 12%-30% performance improvement for UDP traffic. For TCP,
when gro is on no difference as it produces skb with partial
checksum. But when gro is disabled, 20% or even higher improvement
could be measured by netperf.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-11 15:57:47 -07:00
Eric Dumazet
13fcb7bd32 af_packet: prevent information leak
In 2.6.27, commit 393e52e33c (packet: deliver VLAN TCI to userspace)
added a small information leak.

Add padding field and make sure its zeroed before copy to user.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-06 22:42:06 -07:00
Ben Greear
827d978037 af-packet: Use existing netdev reference for bound sockets.
This saves a network device lookup on each packet transmitted,
for sockets that are bound to a network device.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-05 14:16:28 -07:00
Ben Greear
160ff18a07 af-packet: Hold reference to bound network devices.
Old code was probably safe, but with this change we
can actually use the netdev object, not just compare
the pointer values.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-05 14:16:28 -07:00
Ben Greear
a3bcc23e89 af-packet: Add flag to distinguish VID 0 from no-vlan.
Currently, user-space cannot determine if a 0 tcp_vlan_tci
means there is no VLAN tag or the VLAN ID was zero.

Add flag to make this explicit.  User-space can check for
TP_STATUS_VLAN_VALID || tp_vlan_tci > 0, which will be backwards
compatible. Older could would have just checked for tp_vlan_tci,
so it will work no worse than before.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-01 21:18:03 -07:00
Dan Rosenberg
71338aa7d0 net: convert %p usage to %pK
The %pK format specifier is designed to hide exposed kernel pointers,
specifically via /proc interfaces.  Exposing these pointers provides an
easy target for kernel write vulnerabilities, since they reveal the
locations of writable structures containing easily triggerable function
pointers.  The behavior of %pK depends on the kptr_restrict sysctl.

If kptr_restrict is set to 0, no deviation from the standard %p behavior
occurs.  If kptr_restrict is set to 1, the default, if the current user
(intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG
(currently in the LSM tree), kernel pointers using %pK are printed as 0's.
 If kptr_restrict is set to 2, kernel pointers using %pK are printed as
0's regardless of privileges.  Replacing with 0's was chosen over the
default "(null)", which cannot be parsed by userland %p, which expects
"(nil)".

The supporting code for kptr_restrict and %pK are currently in the -mm
tree.  This patch converts users of %p in net/ to %pK.  Cases of printing
pointers to the syslog are not covered, since this would eliminate useful
information for postmortem debugging and the reading of the syslog is
already optionally protected by the dmesg_restrict sysctl.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: James Morris <jmorris@namei.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Thomas Graf <tgraf@infradead.org>
Cc: Eugene Teo <eugeneteo@kernel.org>
Cc: Kees Cook <kees.cook@canonical.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David S. Miller <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-24 01:13:12 -04:00
Eric Dumazet
0a14842f5a net: filter: Just In Time compiler for x86-64
In order to speedup packet filtering, here is an implementation of a
JIT compiler for x86_64

It is disabled by default, and must be enabled by the admin.

echo 1 >/proc/sys/net/core/bpf_jit_enable

It uses module_alloc() and module_free() to get memory in the 2GB text
kernel range since we call helpers functions from the generated code.

EAX : BPF A accumulator
EBX : BPF X accumulator
RDI : pointer to skb   (first argument given to JIT function)
RBP : frame pointer (even if CONFIG_FRAME_POINTER=n)
r9d : skb->len - skb->data_len (headlen)
r8  : skb->data

To get a trace of generated code, use :

echo 2 >/proc/sys/net/core/bpf_jit_enable

Example of generated code :

# tcpdump -p -n -s 0 -i eth1 host 192.168.20.0/24

flen=18 proglen=147 pass=3 image=ffffffffa00b5000
JIT code: ffffffffa00b5000: 55 48 89 e5 48 83 ec 60 48 89 5d f8 44 8b 4f 60
JIT code: ffffffffa00b5010: 44 2b 4f 64 4c 8b 87 b8 00 00 00 be 0c 00 00 00
JIT code: ffffffffa00b5020: e8 24 7b f7 e0 3d 00 08 00 00 75 28 be 1a 00 00
JIT code: ffffffffa00b5030: 00 e8 fe 7a f7 e0 24 00 3d 00 14 a8 c0 74 49 be
JIT code: ffffffffa00b5040: 1e 00 00 00 e8 eb 7a f7 e0 24 00 3d 00 14 a8 c0
JIT code: ffffffffa00b5050: 74 36 eb 3b 3d 06 08 00 00 74 07 3d 35 80 00 00
JIT code: ffffffffa00b5060: 75 2d be 1c 00 00 00 e8 c8 7a f7 e0 24 00 3d 00
JIT code: ffffffffa00b5070: 14 a8 c0 74 13 be 26 00 00 00 e8 b5 7a f7 e0 24
JIT code: ffffffffa00b5080: 00 3d 00 14 a8 c0 75 07 b8 ff ff 00 00 eb 02 31
JIT code: ffffffffa00b5090: c0 c9 c3

BPF program is 144 bytes long, so native program is almost same size ;)

(000) ldh      [12]
(001) jeq      #0x800           jt 2    jf 8
(002) ld       [26]
(003) and      #0xffffff00
(004) jeq      #0xc0a81400      jt 16   jf 5
(005) ld       [30]
(006) and      #0xffffff00
(007) jeq      #0xc0a81400      jt 16   jf 17
(008) jeq      #0x806           jt 10   jf 9
(009) jeq      #0x8035          jt 10   jf 17
(010) ld       [28]
(011) and      #0xffffff00
(012) jeq      #0xc0a81400      jt 16   jf 13
(013) ld       [38]
(014) and      #0xffffff00
(015) jeq      #0xc0a81400      jt 16   jf 17
(016) ret      #65535
(017) ret      #0

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Hagen Paul Pfeifer <hagen@jauu.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-27 23:05:08 -07:00
Hagen Paul Pfeifer
e143038f4d af_packet: struct socket declared/assigned but unused
Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-07 15:51:13 -08:00
Ben Greear
57f89bfa21 network: Allow af_packet to transmit +4 bytes for VLAN packets.
This allows user-space to send a '1500' MTU VLAN packet on a
1500 MTU ethernet frame.  The extra 4 bytes of a VLAN header is
not usually charged against the MTU when other parts of the
network stack is transmitting vlans...

Signed-off-by: Ben Greear <greearb@candelatech.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-11 21:26:32 -08:00
Shan Wei
441c793a56 net: cleanup unused macros in net directory
Clean up some unused macros in net/*.
1. be left for code change. e.g. PGV_FROM_VMALLOC, PGV_FROM_VMALLOC, KMEM_SAFETYZONE.
2. never be used since introduced to kernel.
   e.g. P9_RDMA_MAX_SGE, UTIL_CTRL_PKT_SIZE.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Acked-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-19 23:20:04 -08:00
Eric Dumazet
80f8f1027b net: filter: dont block softirqs in sk_run_filter()
Packet filter (BPF) doesnt need to disable softirqs, being fully
re-entrant and lock-less.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-18 21:33:05 -08:00
Michał Mirosław
55508d601d net: Use skb_checksum_start_offset()
Replace skb->csum_start - skb_headroom(skb) with skb_checksum_start_offset().

Note for usb/smsc95xx: skb->data - skb->head == skb_headroom(skb).

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-16 14:43:14 -08:00
Changli Gao
c053fd96d0 af_packet: use swap() instead of the open coded macro XC()
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-10 16:02:20 -08:00
Changli Gao
920b8d913b af_packet: fix freeing pg_vec twice on error path
It is introduced in:
        commit 0e3125c755
        Author: Neil Horman <nhorman@tuxdriver.com>
        Date:   Tue Nov 16 10:26:47 2010 -0800

        packet: Enhance AF_PACKET implementation to not require high order contiguous memory allocation (v4)

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-08 10:43:41 -08:00
Changli Gao
f6dafa95d1 af_packet: eliminate pgv_to_page on some arches
Some arches don't need flush_dcache_page(), and don't implement it, so
we can eliminate pgv_to_page() calls on those arches.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-08 10:43:41 -08:00
Eric Dumazet
62ab081213 filter: constify sk_run_filter()
sk_run_filter() doesnt write on skb, change its prototype to reflect
this.

Fix two af_packet comments.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-08 10:30:34 -08:00
Changli Gao
c56b4d9012 af_packet: remove pgv.flags
As we can check if an address is vmalloc address with is_vmalloc_addr(),
we remove pgv.flags. Then we may get more pg_vecs.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-06 12:59:07 -08:00
Changli Gao
0af55bb58f af_packet: use vmalloc_to_page() instead for the addresss returned by vmalloc()
The following commit causes the pgv->buffer may point to the memory
returned by vmalloc(). And we can't use virt_to_page() for the vmalloc
address.

This patch introduces a new inline function pgv_to_page(), which calls
vmalloc_to_page() for the vmalloc address, and virt_to_page() for the
__get_free_pages address.

We used to increase page pointer to get the next page at the next page
address, after Neil's patch, it is wrong, as the physical address may
be not continuous. This patch also fixes this issue.

    commit 0e3125c755
    Author: Neil Horman <nhorman@tuxdriver.com>
    Date:   Tue Nov 16 10:26:47 2010 -0800

    packet: Enhance AF_PACKET implementation to not require high order contiguous memory allocation (v4)

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-06 12:59:06 -08:00
Eric Dumazet
bbce5a59e4 packet: use vzalloc()
alloc_one_pg_vec_page() is supposed to return zeroed memory, so use
vzalloc() instead of vmalloc()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-21 10:01:42 -08:00
Eric Dumazet
93aaae2e01 filter: optimize sk_run_filter
Remove pc variable to avoid arithmetic to compute fentry at each filter
instruction. Jumps directly manipulate fentry pointer.

As the last instruction of filter[] is guaranteed to be a RETURN, and
all jumps are before the last instruction, we dont need to check filter
bounds (number of instructions in filter array) at each iteration, so we
remove it from sk_run_filter() params.

On x86_32 remove f_k var introduced in commit 57fe93b374
(filter: make sure filters dont read uninitialized memory)

Note : We could use a CONFIG_ARCH_HAS_{FEW|MANY}_REGISTERS in order to
avoid too many ifdefs in this code.

This helps compiler to use cpu registers to hold fentry and A
accumulator.

On x86_32, this saves 401 bytes, and more important, sk_run_filter()
runs much faster because less register pressure (One less conditional
branch per BPF instruction)

# size net/core/filter.o net/core/filter_pre.o
   text    data     bss     dec     hex filename
   2948       0       0    2948     b84 net/core/filter.o
   3349       0       0    3349     d15 net/core/filter_pre.o

on x86_64 :
# size net/core/filter.o net/core/filter_pre.o
   text    data     bss     dec     hex filename
   5173       0       0    5173    1435 net/core/filter.o
   5224       0       0    5224    1468 net/core/filter_pre.o

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-19 09:49:59 -08:00
Neil Horman
0e3125c755 packet: Enhance AF_PACKET implementation to not require high order contiguous memory allocation (v4)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Version 4 of this patch.

Change notes:
1) Removed extra memset.  Didn't think kcalloc added a GFP_ZERO the way kzalloc did :)

Summary:
It was shown to me recently that systems under high load were driven very deep
into swap when tcpdump was run.  The reason this happened was because the
AF_PACKET protocol has a SET_RINGBUFFER socket option that allows the user space
application to specify how many entries an AF_PACKET socket will have and how
large each entry will be.  It seems the default setting for tcpdump is to set
the ring buffer to 32 entries of 64 Kb each, which implies 32 order 5
allocation.  Thats difficult under good circumstances, and horrid under memory
pressure.

I thought it would be good to make that a bit more usable.  I was going to do a
simple conversion of the ring buffer from contigous pages to iovecs, but
unfortunately, the metadata which AF_PACKET places in these buffers can easily
span a page boundary, and given that these buffers get mapped into user space,
and the data layout doesn't easily allow for a change to padding between frames
to avoid that, a simple iovec change is just going to break user space ABI
consistency.

So I've done this, I've added a three tiered mechanism to the af_packet set_ring
socket option.  It attempts to allocate memory in the following order:

1) Using __get_free_pages with GFP_NORETRY set, so as to fail quickly without
digging into swap

2) Using vmalloc

3) Using __get_free_pages with GFP_NORETRY clear, causing us to try as hard as
needed to get the memory

The effect is that we don't disturb the system as much when we're under load,
while still being able to conduct tcpdumps effectively.

Tested successfully by me.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-16 10:26:47 -08:00
Mariusz Kozlowski
1f18b7176e net: Fix header size check for GSO case in recvmsg (af_packet)
Parameter 'len' is size_t type so it will never get negative.

Signed-off-by: Mariusz Kozlowski <mk@lab.zgora.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-12 11:06:46 -08:00
Vasiliy Kulikov
67286640f6 net: packet: fix information leak to userland
packet_getname_spkt() doesn't initialize all members of sa_data field of
sockaddr struct if strlen(dev->name) < 13.  This structure is then copied
to userland.  It leads to leaking of contents of kernel stack memory.
We have to fully fill sa_data with strncpy() instead of strlcpy().

The same with packet_getname(): it doesn't initialize sll_pkttype field of
sockaddr_ll.  Set it to zero.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-10 12:09:10 -08:00