Граф коммитов

377 Коммитов

Автор SHA1 Сообщение Дата
Francesco Ruggeri 30f7ea1c2b packet: race condition in packet_bind
There is a race conditions between packet_notifier and packet_bind{_spkt}.

It happens if packet_notifier(NETDEV_UNREGISTER) executes between the
time packet_bind{_spkt} takes a reference on the new netdevice and the
time packet_do_bind sets po->ifindex.
In this case the notification can be missed.
If this happens during a dev_change_net_namespace this can result in the
netdevice to be moved to the new namespace while the packet_sock in the
old namespace still holds a reference on it. When the netdevice is later
deleted in the new namespace the deletion hangs since the packet_sock
is not found in the new namespace' &net->packet.sklist.
It can be reproduced with the script below.

This patch makes packet_do_bind check again for the presence of the
netdevice in the packet_sock's namespace after the synchronize_net
in unregister_prot_hook.
More in general it also uses the rcu lock for the duration of the bind
to stop dev_change_net_namespace/rollback_registered_many from
going past the synchronize_net following unlist_netdevice, so that
no NETDEV_UNREGISTER notifications can happen on the new netdevice
while the bind is executing. In order to do this some code from
packet_bind{_spkt} is consolidated into packet_do_dev.

import socket, os, time, sys
proto=7
realDev='em1'
vlanId=400
if len(sys.argv) > 1:
   vlanId=int(sys.argv[1])
dev='vlan%d' % vlanId

os.system('taskset -p 0x10 %d' % os.getpid())

s = socket.socket(socket.PF_PACKET, socket.SOCK_RAW, proto)
os.system('ip link add link %s name %s type vlan id %d' %
          (realDev, dev, vlanId))
os.system('ip netns add dummy')

pid=os.fork()

if pid == 0:
   # dev should be moved while packet_do_bind is in synchronize net
   os.system('taskset -p 0x20000 %d' % os.getpid())
   os.system('ip link set %s netns dummy' % dev)
   os.system('ip netns exec dummy ip link del %s' % dev)
   s.close()
   sys.exit(0)

time.sleep(.004)
try:
   s.bind(('%s' % dev, proto+1))
except:
   print 'Could not bind socket'
   s.close()
   os.system('ip netns del dummy')
   sys.exit(0)

os.waitpid(pid, 0)
s.close()
os.system('ip netns del dummy')
sys.exit(0)

Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-05 14:48:42 -05:00
Eric W. Biederman 19bcf9f203 ipv4: Pass struct net into ip_defrag and ip_check_defrag
The function ip_defrag is called on both the input and the output
paths of the networking stack.  In particular conntrack when it is
tracking outbound packets from the local machine calls ip_defrag.

So add a struct net parameter and stop making ip_defrag guess which
network namespace it needs to defragment packets in.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12 19:44:16 -07:00
Eric Dumazet 161642e24f packet: fix match_fanout_group()
Recent TCP listener patches exposed a prior af_packet bug :
match_fanout_group() blindly assumes it is always safe
to cast sk to a packet socket to compare fanout with af_packet_priv

But SYNACK packets can be sent while attached to request_sock, which
are smaller than a "struct sock".

We can read non existent memory and crash.

Fixes: c0de08d042 ("af_packet: don't emit packet on orig fanout group")
Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Eric Leblond <eric@regit.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12 19:42:38 -07:00
Edward Jee c7d39e3263 packet: support per-packet fwmark for af_packet sendmsg
Signed-off-by: Edward Hyunkoo Jee <edjee@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12 19:25:22 -07:00
Alexei Starovoitov ff936a04e5 bpf: fix cb access in socket filter programs
eBPF socket filter programs may see junk in 'u32 cb[5]' area,
since it could have been used by protocol layers earlier.

For socket filter programs used in af_packet we need to clean
20 bytes of skb->cb area if it could be used by the program.
For programs attached to TCP/UDP sockets we need to save/restore
these 20 bytes, since it's used by protocol layers.

Remove SK_RUN_FILTER macro, since it's no longer used.

Long term we may move this bpf cb area to per-cpu scratch, but that
requires addition of new 'per-cpu load/store' instructions,
so not suitable as a short term fix.

Fixes: d691f9e8d4 ("bpf: allow programs to write to certain skb fields")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-11 04:40:05 -07:00
Daniel Borkmann bab1899187 bpf, seccomp: prepare for upcoming criu support
The current ongoing effort to dump existing cBPF seccomp filters back
to user space requires to hold the pre-transformed instructions like
we do in case of socket filters from sk_attach_filter() side, so they
can be reloaded in original form at a later point in time by utilities
such as criu.

To prepare for this, simply extend the bpf_prog_create_from_user()
API to hold a flag that tells whether we should store the original
or not. Also, fanout filters could make use of that in future for
things like diag. While fanout filters already use bpf_prog_destroy(),
move seccomp over to them as well to handle original programs when
present.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Tycho Andersen <tycho.andersen@canonical.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Tested-by: Tycho Andersen <tycho.andersen@canonical.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05 06:47:05 -07:00
David Woodhouse d3869efe7a Fix AF_PACKET ABI breakage in 4.2
Commit 7d82410950 ("virtio: add explicit big-endian support to memory
accessors") accidentally changed the virtio_net header used by
AF_PACKET with PACKET_VNET_HDR from host-endian to big-endian.

Since virtio_legacy_is_little_endian() is a very long identifier,
define a vio_le macro and use that throughout the code instead of the
hard-coded 'false' for little-endian.

This restores the ABI to match 4.1 and earlier kernels, and makes my
test program work again.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-23 14:33:55 -07:00
Willem de Bruijn f2e520956a packet: add extended BPF fanout mode
Add fanout mode PACKET_FANOUT_EBPF that accepts an en extended BPF
program to select a socket.

Update the internal eBPF program by passing to socket option
SOL_PACKET/PACKET_FANOUT_DATA a file descriptor returned by bpf().

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17 14:22:48 -07:00
Willem de Bruijn 47dceb8ecd packet: add classic BPF fanout mode
Add fanout mode PACKET_FANOUT_CBPF that accepts a classic BPF program
to select a socket.

This avoids having to keep adding special case fanout modes. One
example use case is application layer load balancing. The QUIC
protocol, for instance, encodes a connection ID in UDP payload.

Also add socket option SOL_PACKET/PACKET_FANOUT_DATA that updates data
associated with the socket group. Fanout mode PACKET_FANOUT_CBPF is the
only user so far.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17 14:22:47 -07:00
David S. Miller 5510b3c2a1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	arch/s390/net/bpf_jit_comp.c
	drivers/net/ethernet/ti/netcp_ethss.c
	net/bridge/br_multicast.c
	net/ipv4/ip_fragment.c

All four conflicts were cases of simple overlapping
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 23:52:20 -07:00
Tobias Klauser 73d0fcf2f4 packet: remove handling of tx_ring from prb_shutdown_retire_blk_timer()
Follow e8e85cc5eb ("packet: remove handling of tx_ring") and remove
the tx_ring parameter from prb_shutdown_retire_blk_timer() as it is only
called with tx_ring = 0.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 15:11:12 -07:00
Alexander Drozdov dbd46ab412 packet: tpacket_snd(): fix signed/unsigned comparison
tpacket_fill_skb() can return a negative value (-errno) which
is stored in tp_len variable. In that case the following
condition will be (but shouldn't be) true:

tp_len > dev->mtu + dev->hard_header_len

as dev->mtu and dev->hard_header_len are both unsigned.

That may lead to just returning an incorrect EMSGSIZE errno
to the user.

Fixes: 52f1454f62 ("packet: allow to transmit +4 byte in TX_RING slot for VLAN case")
Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 00:09:58 -07:00
Lars Westerhoff 158cd4af8d packet: missing dev_put() in packet_do_bind()
When binding a PF_PACKET socket, the use count of the bound interface is
always increased with dev_hold in dev_get_by_{index,name}.  However,
when rebound with the same protocol and device as in the previous bind
the use count of the interface was not decreased.  Ultimately, this
caused the deletion of the interface to fail with the following message:

unregister_netdevice: waiting for dummy0 to become free. Usage count = 1

This patch moves the dev_put out of the conditional part that was only
executed when either the protocol or device changed on a bind.

Fixes: 902fefb82e ('packet: improve socket create/bind latency in some cases')
Signed-off-by: Lars Westerhoff <lars.westerhoff@newtec.eu>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 15:38:58 -07:00
David S. Miller 3a07bd6fea Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/mellanox/mlx4/main.c
	net/packet/af_packet.c

Both conflicts were cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24 02:58:51 -07:00
Maninder Singh e8e85cc5eb packet: remove handling of tx_ring
Remove handling of tx_ring in prb_setup_retire_blk_timer
for TPACKET_V3 because init_prb_bdqc is called only for zero tx_ring
and thus prb_setup_retire_blk_timer for zero tx_ring only.

And also in functon init_prb_bdqc there is no usage of tx_ring.
Thus removing tx_ring from init_prb_bdqc.

Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Suggested-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-23 06:53:29 -07:00
Willem de Bruijn 468479e604 packet: avoid out of bounds read in round robin fanout
PACKET_FANOUT_LB computes f->rr_cur such that it is modulo
f->num_members. It returns the old value unconditionally, but
f->num_members may have changed since the last store. Ensure
that the return value is always < num.

When modifying the logic, simplify it further by replacing the loop
with an unconditional atomic increment.

Fixes: dc99f60069 ("packet: Add fanout support.")
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-21 10:24:37 -07:00
Willem de Bruijn 59f211181b packet: free packet_rollover after synchronize_net
Destruction of the po->rollover must be delayed until there are no
more packets in flight that can access it. The field is destroyed in
packet_release, before synchronize_net. Delay using rcu.

Fixes: 0648ab70af ("packet: rollover prepare: per-socket state")

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-21 09:30:42 -07:00
Eric Dumazet f98f4514d0 packet: read num_members once in packet_rcv_fanout()
We need to tell compiler it must not read f->num_members multiple
times. Otherwise testing if num is not zero is flaky, and we could
attempt an invalid divide by 0 in fanout_demux_cpu()

Note bug was present in packet_rcv_fanout_hash() and
packet_rcv_fanout_lb() but final 3.1 had a simple location
after commit 95ec3eb417 ("packet: Add 'cpu' fanout policy.")

Fixes: dc99f60069 ("packet: Add fanout support.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-21 09:23:22 -07:00
Willem de Bruijn 4633c9e07b net-packet: fix null pointer exception in rollover mode
Rollover can be enabled as flag or mode. Allocate state in both cases.
This solves a NULL pointer exception in fanout_demux_rollover on
referencing po->rollover if using mode rollover.

Also make sure that in rollover mode each silo is tried (contrary
to rollover flag, where the main socket is excluded after an initial
try_self).

Tested:
  Passes tools/testing/net/psock_fanout.c, which tests both modes and
  flag. My previous tests were limited to bench_rollover, which only
  stresses the flag. The test now completes safely. it still gives an
  error for mode rollover, because it does not expect the new headroom
  (ROOM_NORMAL) requirement. I will send a separate patch to the test.

Fixes: 0648ab70af ("packet: rollover prepare: per-socket state")

Signed-off-by: Willem de Bruijn <willemb@google.com>

----

I should have run this test and caught this before submission, of
course. Apologies for the oversight.
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17 22:41:38 -04:00
Willem de Bruijn 54d7c01d3e packet: fix warnings in rollover lock contention
Avoid two xchg calls whose return values were unused, causing a
warning on some architectures.

The relevant variable is a hint and read without mutual exclusion.
This fix makes all writers hold the receive_queue lock.

Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14 17:40:54 -04:00
Willem de Bruijn a9b6391814 packet: rollover statistics
Rollover indicates exceptional conditions. Export a counter to inform
socket owners of this state.

If no socket with sufficient room is found, rollover fails. Also count
these events.

Finally, also count when flows are rolled over early thanks to huge
flow detection, to validate its correctness.

Tested:
  Read counters in bench_rollover on all other tests in the patchset

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:43:00 -04:00
Willem de Bruijn 3b3a5b0aab packet: rollover huge flows before small flows
Migrate flows from a socket to another socket in the fanout group not
only when the socket is full. Start migrating huge flows early, to
divert possible 4-tuple attacks without affecting normal traffic.

Introduce fanout_flow_is_huge(). This detects huge flows, which are
defined as taking up more than half the load. It does so cheaply, by
storing the rxhashes of the N most recent packets. If over half of
these are the same rxhash as the current packet, then drop it. This
only protects against 4-tuple attacks. N is chosen to fit all data in
a single cache line.

Tested:
  Ran bench_rollover for 10 sec with 1.5 Mpps of single flow input.

    lpbb5:/export/hda3/willemb# ./bench_rollover -l 1000 -r -s
    cpu         rx       rx.k     drop.k   rollover     r.huge   r.failed
      0         14         14          0          0          0          0
      1         20         20          0          0          0          0
      2         16         16          0          0          0          0
      3    6168824    6168824          0    4867721    4867721          0
      4    4867741    4867741          0          0          0          0
      5         12         12          0          0          0          0
      6         15         15          0          0          0          0
      7         17         17          0          0          0          0

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:43:00 -04:00
Willem de Bruijn 2ccdbaa6d5 packet: rollover lock contention avoidance
Rollover has to call packet_rcv_has_room on sockets in the fanout
group to find a socket to migrate to. This operation is expensive
especially if the packet sockets use rings, when a lock has to be
acquired.

Avoid pounding on the lock by all sockets by temporarily marking a
socket as "under memory pressure" when such pressure is detected.
While set, only the socket owner may call packet_rcv_has_room on the
socket. Once it detects normal conditions, it clears the flag. The
socket is not used as a victim by any other socket in the meantime.

Under reasonably balanced load, each socket writer frequently calls
packet_rcv_has_room and clears its own pressure field. As a backup
for when the socket is rarely written to, also clear the flag on
reading (packet_recvmsg, packet_poll) if this can be done cheaply
(i.e., without calling packet_rcv_has_room). This is only for
edge cases.

Tested:
  Ran bench_rollover: a process with 8 sockets in a single fanout
  group, each pinned to a single cpu that receives one nic recv
  interrupt. RPS and RFS are disabled. The benchmark uses packet
  rx_ring, which has to take a lock when determining whether a
  socket has room.

  Sent 3.5 Mpps of UDP traffic with sufficient entropy to spread
  uniformly across the packet sockets (and inserted an iptables
  rule to drop in PREROUTING to avoid protocol stack processing).

  Without this patch, all sockets try to migrate traffic to
  neighbors, causing lock contention when searching for a non-
  empty neighbor. The lock is the top 9 entries.

    perf record -a -g sleep 5

    -  17.82%   bench_rollover  [kernel.kallsyms]    [k] _raw_spin_lock
       - _raw_spin_lock
          - 99.00% spin_lock
    	 + 81.77% packet_rcv_has_room.isra.41
    	 + 18.23% tpacket_rcv
          + 0.84% packet_rcv_has_room.isra.41
    +   5.20%      ksoftirqd/6  [kernel.kallsyms]    [k] _raw_spin_lock
    +   5.15%      ksoftirqd/1  [kernel.kallsyms]    [k] _raw_spin_lock
    +   5.14%      ksoftirqd/2  [kernel.kallsyms]    [k] _raw_spin_lock
    +   5.12%      ksoftirqd/7  [kernel.kallsyms]    [k] _raw_spin_lock
    +   5.12%      ksoftirqd/5  [kernel.kallsyms]    [k] _raw_spin_lock
    +   5.10%      ksoftirqd/4  [kernel.kallsyms]    [k] _raw_spin_lock
    +   4.66%      ksoftirqd/0  [kernel.kallsyms]    [k] _raw_spin_lock
    +   4.45%      ksoftirqd/3  [kernel.kallsyms]    [k] _raw_spin_lock
    +   1.55%   bench_rollover  [kernel.kallsyms]    [k] packet_rcv_has_room.isra.41

  On net-next with this patch, this lock contention is no longer a
  top entry. Most time is spent in the actual read function. Next up
  are other locks:

    +  15.52%  bench_rollover  bench_rollover     [.] reader
    +   4.68%         swapper  [kernel.kallsyms]  [k] memcpy_erms
    +   2.77%         swapper  [kernel.kallsyms]  [k] packet_lookup_frame.isra.51
    +   2.56%     ksoftirqd/1  [kernel.kallsyms]  [k] memcpy_erms
    +   2.16%         swapper  [kernel.kallsyms]  [k] tpacket_rcv
    +   1.93%         swapper  [kernel.kallsyms]  [k] mlx4_en_process_rx_cq

  Looking closer at the remaining _raw_spin_lock, the cost of probing
  in rollover is now comparable to the cost of taking the lock later
  in tpacket_rcv.

    -   1.51%         swapper  [kernel.kallsyms]  [k] _raw_spin_lock
       - _raw_spin_lock
          + 33.41% packet_rcv_has_room
          + 28.15% tpacket_rcv
          + 19.54% enqueue_to_backlog
          + 6.45% __free_pages_ok
          + 2.78% packet_rcv_fanout
          + 2.13% fanout_demux_rollover
          + 2.01% netif_receive_skb_internal

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:43:00 -04:00
Willem de Bruijn 9954729bc3 packet: rollover only to socket with headroom
Only migrate flows to sockets that have sufficient headroom, where
sufficient is defined as having at least 25% empty space.

The kernel has three different buffer types: a regular socket, a ring
with frames (TPACKET_V[12]) or a ring with blocks (TPACKET_V3). The
latter two do not expose a read pointer to the kernel, so headroom is
not computed easily. All three needs a different implementation to
estimate free space.

Tested:
  Ran bench_rollover for 10 sec with 1.5 Mpps of single flow input.

  bench_rollover has as many sockets as there are NIC receive queues
  in the system. Each socket is owned by a process that is pinned to
  one of the receive cpus. RFS is disabled. RPS is enabled with an
  identity mapping (cpu x -> cpu x), to count drops with softnettop.

    lpbb5:/export/hda3/willemb# ./bench_rollover -r -l 1000 -s
    Press [Enter] to exit

    cpu         rx       rx.k     drop.k   rollover     r.huge   r.failed
      0         16         16          0          0          0          0
      1         21         21          0          0          0          0
      2    5227502    5227502          0          0          0          0
      3         18         18          0          0          0          0
      4    6083289    6083289          0    5227496          0          0
      5         22         22          0          0          0          0
      6         21         21          0          0          0          0
      7          9          9          0          0          0          0

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:42:59 -04:00
Willem de Bruijn 0648ab70af packet: rollover prepare: per-socket state
Replace rollover state per fanout group with state per socket. Future
patches will add fields to the new structure.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:42:59 -04:00
Willem de Bruijn ad377cab49 packet: rollover prepare: move code out of callsites
packet_rcv_fanout calls fanout_demux_rollover twice. Move all rollover
logic into the callee to simplify these callsites, especially with
upcoming changes.

The main differences between the two callsites is that the FLAG
variant tests whether the socket previously selected by another
mode (RR, RND, HASH, ..) has room before migrating flows, whereas the
rollover mode has no original socket to test.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:42:59 -04:00
David S. Miller b04096ff33 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Four minor merge conflicts:

1) qca_spi.c renamed the local variable used for the SPI device
   from spi_device to spi, meanwhile the spi_set_drvdata() call
   got moved further up in the probe function.

2) Two changes were both adding new members to codel params
   structure, and thus we had overlapping changes to the
   initializer function.

3) 'net' was making a fix to sk_release_kernel() which is
   completely removed in 'net-next'.

4) In net_namespace.c, the rtnl_net_fill() call for GET operations
   had the command value fixed, meanwhile 'net-next' adjusted the
   argument signature a bit.

This also matches example merge resolutions posted by Stephen
Rothwell over the past two days.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 14:31:43 -04:00
Eric W. Biederman 11aa9c28b4 net: Pass kern from net_proto_family.create to sk_alloc
In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:50:17 -04:00
Kretschmer, Mathias fbf33a2802 af_packet / TX_RING not fully non-blocking (w/ MSG_DONTWAIT).
This patch fixes an issue where the send(MSG_DONTWAIT) call
on a TX_RING is not fully non-blocking in cases where the device's sndBuf is
full. We pass nonblock=true to sock_alloc_send_skb() and return any possibly
occuring error code (most likely EGAIN) to the caller. As the fast-path stays
as it is, we keep the unlikely() around skb == NULL.

Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-10 19:40:08 -04:00
Alexander Drozdov 682f048bd4 af_packet: pass checksum validation status to the user
Introduce TP_STATUS_CSUM_VALID tp_status flag to tell the
af_packet user that at least the transport header checksum
has been already validated.

For now, the flag may be set for incoming packets only.

Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-23 22:01:28 -04:00
Alexander Drozdov 68c2e5de36 af_packet: make tpacket_rcv to not set status value before run_filter
It is just an optimization. We don't need the value of status variable
if the packet is filtered.

Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-23 22:00:36 -04:00
Eric W. Biederman 0c5c9fb551 net: Introduce possible_net_t
Having to say
> #ifdef CONFIG_NET_NS
> 	struct net *net;
> #endif

in structures is a little bit wordy and a little bit error prone.

Instead it is possible to say:
> typedef struct {
> #ifdef CONFIG_NET_NS
>       struct net *net;
> #endif
> } possible_net_t;

And then in a header say:

> 	possible_net_t net;

Which is cleaner and easier to use and easier to test, as the
possible_net_t is always there no matter what the compile options.

Further this allows read_pnet and write_pnet to be functions in all
cases which is better at catching typos.

This change adds possible_net_t, updates the definitions of read_pnet
and write_pnet, updates optional struct net * variables that
write_pnet uses on to have the type possible_net_t, and finally fixes
up the b0rked users of read_pnet and write_pnet.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-12 14:39:40 -04:00
David S. Miller 3cef5c5b0b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/cadence/macb.c

Overlapping changes in macb driver, mostly fixes and cleanups
in 'net' overlapping with the integration of at91_ether into
macb in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-09 23:38:02 -04:00
Francesco Ruggeri 82f17091e6 net: delete stale packet_mclist entries
When an interface is deleted from a net namespace the ifindex in the
corresponding entries in PF_PACKET sockets' mclists becomes stale.
This can create inconsistencies if later an interface with the same ifindex
is moved from a different namespace (not that unlikely since ifindexes are
per-namespace).
In particular we saw problems with dev->promiscuity, resulting
in "promiscuity touches roof, set promiscuity failed. promiscuity
feature of device might be broken" warnings and EOVERFLOW failures of
setsockopt(PACKET_ADD_MEMBERSHIP).
This patch deletes the mclist entries for interfaces that are deleted.
Since this now causes setsockopt(PACKET_DROP_MEMBERSHIP) to fail with
EADDRNOTAVAIL if called after the interface is deleted, also make
packet_mc_drop not fail.

Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-09 16:17:43 -04:00
David S. Miller 71a83a6db6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/rocker/rocker.c

The rocker commit was two overlapping changes, one to rename
the ->vport member to ->pport, and another making the bitmask
expression use '1ULL' instead of plain '1'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-03 21:16:48 -05:00
Ying Xue 1b78414047 net: Remove iocb argument from sendmsg and recvmsg
After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.

Cc: Christoph Hellwig <hch@lst.de>
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02 13:06:31 -05:00
Eyal Birger 3bc3b96f3b net: add common accessor for setting dropcount on packets
As part of an effort to move skb->dropcount to skb->cb[], use
a common function in order to set dropcount in struct sk_buff.

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02 00:19:30 -05:00
Eyal Birger b4772ef879 net: use common macro for assering skb->cb[] available size in protocol families
As part of an effort to move skb->dropcount to skb->cb[] use a common
macro in protocol families using skb->cb[] for ancillary data to
validate available room in skb->cb[].

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02 00:19:30 -05:00
Eyal Birger 2472d7613b net: packet: use sockaddr_ll fields as storage for skb original length in recvmsg path
As part of an effort to move skb->dropcount to skb->cb[], 4 bytes
of additional room are needed in skb->cb[] in packet sockets.

Store the skb original length in the first two fields of sockaddr_ll
(sll_family and sll_protocol) as they can be derived from the skb when
needed.

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02 00:19:29 -05:00
Alexander Drozdov 41a50d621a af_packet: don't pass empty blocks for PACKET_V3
Before da413eec72 ("packet: Fixed TPACKET V3 to signal poll when block is
closed rather than every packet") poll listening for an af_packet socket was
not signaled if there was no packets to process. After the patch poll is
signaled evety time when block retire timer expires. That happens because
af_packet closes the current block on timeout even if the block is empty.

Passing empty blocks to the user not only wastes CPU but also wastes ring
buffer space increasing probability of packets dropping on small timeouts.

Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com>
Cc: Dan Collins <dan@dcollins.co.nz>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Guy Harris <guy@alum.mit.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-24 16:08:42 -05:00
Alexander Drozdov 3f34b24a73 af_packet: allow packets defragmentation not only for hash fanout type
Packets defragmentation was introduced for PACKET_FANOUT_HASH only,
see 7736d33f42 ("packet: Add pre-defragmentation support for ipv4
fanouts")

It may be useful to have defragmentation enabled regardless of
fanout type. Without that, the AF_PACKET user may have to:
1. Collect fragments from different rings
2. Defragment by itself

Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-21 23:00:18 -05:00
Johannes Berg 053c095a82 netlink: make nlmsg_end() and genlmsg_end() void
Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.

This makes the very common pattern of

  if (genlmsg_end(...) < 0) { ... }

be a whole bunch of dead code. Many places also simply do

  return nlmsg_end(...);

and the caller is expected to deal with it.

This also commonly (at least for me) causes errors, because it is very
common to write

  if (my_function(...))
    /* error condition */

and if my_function() does "return nlmsg_end()" this is of course wrong.

Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.

Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did

-	return nlmsg_end(...);
+	nlmsg_end(...);
+	return 0;

I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.

One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18 01:03:45 -05:00
David S. Miller 3f3558bb51 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/xen-netfront.c

Minor overlapping changes in xen-netfront.c, mostly to do
with some buffer management changes alongside the split
of stats into TX and RX.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-15 00:53:17 -05:00
Jiri Pirko df8a39defa net: rename vlan_tx_* helpers since "tx" is misleading there
The same macros are used for rx as well. So rename it.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-13 17:51:08 -05:00
Willem de Bruijn eee2f04b80 packet: make packet too small warning match condition
The expression in ll_header_truncated() tests less than or equal, but
the warning prints less than. Update the warning.

Reported-by: Jouni Malinen <jkmalinen@gmail.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:00:55 -05:00
Christoph Jaeger 46d2cfb192 packet: bail out of packet_snd() if L2 header creation fails
Due to a misplaced parenthesis, the expression

  (unlikely(offset) < 0),

which expands to

  (__builtin_expect(!!(offset), 0) < 0),

never evaluates to true. Therefore, when sending packets with
PF_PACKET/SOCK_DGRAM, packet_snd() does not abort as intended
if the creation of the layer 2 header fails.

Spotted by Coverity - CID 1259975 ("Operands don't affect result").

Fixes: 9c7077622d ("packet: make packet_snd fail on len smaller than l2 header")
Signed-off-by: Christoph Jaeger <cj@linux.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-11 21:54:03 -05:00
Dan Collins da413eec72 packet: Fixed TPACKET V3 to signal poll when block is closed rather than every packet
Make TPACKET_V3 signal poll when block is closed rather than for every
packet. Side effect is that poll will be signaled when block retire
timer expires which didn't previously happen. Issue was visible when
sending packets at a very low frequency such that all blocks are retired
before packets are received by TPACKET_V3. This caused avoidable packet
loss. The fix ensures that the signal is sent when blocks are closed
which covers the normal path where the block is filled as well as the
path where the timer expires. The case where a block is filled without
moving to the next block (ie. all blocks are full) will still cause poll
to be signaled.

Signed-off-by: Dan Collins <dan@dcollins.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-22 15:41:15 -05:00
Linus Torvalds 70e71ca0af Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) New offloading infrastructure and example 'rocker' driver for
    offloading of switching and routing to hardware.

    This work was done by a large group of dedicated individuals, not
    limited to: Scott Feldman, Jiri Pirko, Thomas Graf, John Fastabend,
    Jamal Hadi Salim, Andy Gospodarek, Florian Fainelli, Roopa Prabhu

 2) Start making the networking operate on IOV iterators instead of
    modifying iov objects in-situ during transfers.  Thanks to Al Viro
    and Herbert Xu.

 3) A set of new netlink interfaces for the TIPC stack, from Richard
    Alpe.

 4) Remove unnecessary looping during ipv6 routing lookups, from Martin
    KaFai Lau.

 5) Add PAUSE frame generation support to gianfar driver, from Matei
    Pavaluca.

 6) Allow for larger reordering levels in TCP, which are easily
    achievable in the real world right now, from Eric Dumazet.

 7) Add a variable of napi_schedule that doesn't need to disable cpu
    interrupts, from Eric Dumazet.

 8) Use a doubly linked list to optimize neigh_parms_release(), from
    Nicolas Dichtel.

 9) Various enhancements to the kernel BPF verifier, and allow eBPF
    programs to actually be attached to sockets.  From Alexei
    Starovoitov.

10) Support TSO/LSO in sunvnet driver, from David L Stevens.

11) Allow controlling ECN usage via routing metrics, from Florian
    Westphal.

12) Remote checksum offload, from Tom Herbert.

13) Add split-header receive, BQL, and xmit_more support to amd-xgbe
    driver, from Thomas Lendacky.

14) Add MPLS support to openvswitch, from Simon Horman.

15) Support wildcard tunnel endpoints in ipv6 tunnels, from Steffen
    Klassert.

16) Do gro flushes on a per-device basis using a timer, from Eric
    Dumazet.  This tries to resolve the conflicting goals between the
    desired handling of bulk vs.  RPC-like traffic.

17) Allow userspace to ask for the CPU upon what a packet was
    received/steered, via SO_INCOMING_CPU.  From Eric Dumazet.

18) Limit GSO packets to half the current congestion window, from Eric
    Dumazet.

19) Add a generic helper so that all drivers set their RSS keys in a
    consistent way, from Eric Dumazet.

20) Add xmit_more support to enic driver, from Govindarajulu
    Varadarajan.

21) Add VLAN packet scheduler action, from Jiri Pirko.

22) Support configurable RSS hash functions via ethtool, from Eyal
    Perry.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1820 commits)
  Fix race condition between vxlan_sock_add and vxlan_sock_release
  net/macb: fix compilation warning for print_hex_dump() called with skb->mac_header
  net/mlx4: Add support for A0 steering
  net/mlx4: Refactor QUERY_PORT
  net/mlx4_core: Add explicit error message when rule doesn't meet configuration
  net/mlx4: Add A0 hybrid steering
  net/mlx4: Add mlx4_bitmap zone allocator
  net/mlx4: Add a check if there are too many reserved QPs
  net/mlx4: Change QP allocation scheme
  net/mlx4_core: Use tasklet for user-space CQ completion events
  net/mlx4_core: Mask out host side virtualization features for guests
  net/mlx4_en: Set csum level for encapsulated packets
  be2net: Export tunnel offloads only when a VxLAN tunnel is created
  gianfar: Fix dma check map error when DMA_API_DEBUG is enabled
  cxgb4/csiostor: Don't use MASTER_MUST for fw_hello call
  net: fec: only enable mdio interrupt before phy device link up
  net: fec: clear all interrupt events to support i.MX6SX
  net: fec: reset fep link status in suspend function
  net: sock: fix access via invalid file descriptor
  net: introduce helper macro for_each_cmsghdr
  ...
2014-12-11 14:27:06 -08:00
Al Viro c0371da604 put iov_iter into msghdr
Note that the code _using_ ->msg_iter at that point will be very
unhappy with anything other than unshifted iovec-backed iov_iter.
We still need to convert users to proper primitives.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-09 16:29:03 -05:00
Michael S. Tsirkin dc9e51534b af_packet: virtio 1.0 stubs
This merely fixes sparse warnings, without actually
adding support for the new APIs.

Still working out the best way to enable the new
functionality.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:06:32 +02:00
David S. Miller 60b7379dc5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-11-29 20:47:48 -08:00
Michael S. Tsirkin 6e58040b84 af_packet: fix sparse warning
af_packet produces lots of these:
	net/packet/af_packet.c:384:39: warning: incorrect type in return expression (different modifiers)
	net/packet/af_packet.c:384:39:    expected struct page [pure] *
	net/packet/af_packet.c:384:39:    got struct page *

this seems to be because sparse does not realize that _pure
refers to function, not the returned pointer.

Tweak code slightly to avoid the warning.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-24 16:15:36 -05:00
Al Viro 8feb2fb2bb switch AF_PACKET and AF_UNIX to skb_copy_datagram_from_iter()
... and kill skb_copy_datagram_iovec()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24 05:16:39 -05:00
Al Viro 7eab8d9e8a new helper: memcpy_to_msg()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24 04:28:51 -05:00
Al Viro 6ce8e9ce59 new helper: memcpy_from_msg()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24 04:28:48 -05:00
Willem de Bruijn 9c7077622d packet: make packet_snd fail on len smaller than l2 header
When sending packets out with PF_PACKET, SOCK_RAW, ensure that the
packet is at least as long as the device's expected link layer header.
This check already exists in tpacket_snd, but not in packet_snd.
Also rate limit the warning in tpacket_snd.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-21 14:43:07 -05:00
David S. Miller 51f3d02b98 net: Add and use skb_copy_datagram_msg() helper.
This encapsulates all of the skb_copy_datagram_iovec() callers
with call argument signature "skb, offset, msghdr->msg_iov, length".

When we move to iov_iters in the networking, the iov_iter object will
sit in the msghdr.

Having a helper like this means there will be less places to touch
during that transformation.

Based upon descriptions and patch from Al Viro.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-05 16:46:40 -05:00
David S. Miller fa2dbdc253 net: Pass a "more" indication down into netdev_start_xmit() code paths.
For now it will always be false.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:55 -07:00
David S. Miller 10b3ad8c21 net: Do txq_trans_update() in netdev_start_xmit()
That way we don't have to audit every call site to make sure it is
doing this properly.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:55 -07:00
Daniel Borkmann 10c51b5623 net: add skb_get_tx_queue() helper
Replace occurences of skb_get_queue_mapping() and follow-up
netdev_get_tx_queue() with an actual helper function.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-29 20:02:07 -07:00
David S. Miller 4798248e4e net: Add ops->ndo_xmit_flush()
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-24 23:02:45 -07:00
Eric Dumazet dc808110bb packet: handle too big packets for PACKET_V3
af_packet can currently overwrite kernel memory by out of bound
accesses, because it assumed a [new] block can always hold one frame.

This is not generally the case, even if most existing tools do it right.

This patch clamps too long frames as API permits, and issue a one time
error on syslog.

[  394.357639] tpacket_rcv: packet too big, clamped from 5042 to 3966. macoff=82

In this example, packet header tp_snaplen was set to 3966,
and tp_len was set to 5042 (skb->len)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: f6fb8f100b ("af-packet: TPACKET_V3 flexible buffer implementation.")
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-21 16:44:28 -07:00
Willem de Bruijn 68a360e82e packet: remove deprecated syststamp timestamp
No device driver will ever return an skb_shared_info structure with
syststamp non-zero, so remove the branch that tests for this and
optionally marks the packet timestamp as TP_STATUS_TS_SYS_HARDWARE.

Do not remove the definition TP_STATUS_TS_SYS_HARDWARE, as processes
may refer to it.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-29 11:39:50 -07:00
Fabian Frederick fe8c0f4ac2 packet: remove unnecessary break after return
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-15 16:26:59 -07:00
Eric W. Biederman 90f62cf30a net: Use netlink_ns_capable to verify the permisions of netlink messages
It is possible by passing a netlink socket to a more privileged
executable and then to fool that executable into writing to the socket
data that happens to be valid netlink message to do something that
privileged executable did not intend to do.

To keep this from happening replace bare capable and ns_capable calls
with netlink_capable, netlink_net_calls and netlink_ns_capable calls.
Which act the same as the previous calls except they verify that the
opener of the socket had the desired permissions as well.

Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-24 13:44:54 -04:00
Eric W. Biederman a53b72c83a net: Move the permission check in sock_diag_put_filterinfo to packet_diag_dump
The permission check in sock_diag_put_filterinfo is wrong, and it is so removed
from it's sources it is not clear why it is wrong.  Move the computation
into packet_diag_dump and pass a bool of the result into sock_diag_filterinfo.

This does not yet correct the capability check but instead simply moves it to make
it clear what is going on.

Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-24 13:44:53 -04:00
Andrew Lutomirski 78541c1dc6 net: Fix ns_capable check in sock_diag_put_filterinfo
The caller needs capabilities on the namespace being queried, not on
their own namespace.  This is a security bug, although it likely has
only a minor impact.

Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22 12:49:39 -04:00
David S. Miller 676d23690f net: Fix use after free by removing length arg from sk_data_ready callbacks.
Several spots in the kernel perform a sequence like:

	skb_queue_tail(&sk->s_receive_queue, skb);
	sk->sk_data_ready(sk, skb->len);

But at the moment we place the SKB onto the socket receive queue it
can be consumed and freed up.  So this skb->len access is potentially
to freed up memory.

Furthermore, the skb->len can be modified by the consumer so it is
possible that the value isn't accurate.

And finally, no actual implementation of this callback actually uses
the length argument.  And since nobody actually cared about it's
value, lots of call sites pass arbitrary values in such as '0' and
even '1'.

So just remove the length argument from the callback, that way there
is no confusion whatsoever and all of these use-after-free cases get
fixed as a side effect.

Based upon a patch by Eric Dumazet and his suggestion to audit this
issue tree-wide.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-11 16:15:36 -04:00
Daniel Borkmann 8e2f1a63f2 packet: fix packet_direct_xmit for BQL enabled drivers
Currently, in packet_direct_xmit() we test the assigned netdevice queue
for netif_xmit_frozen_or_stopped() before doing an ndo_start_xmit().

This can have the side-effect that BQL enabled drivers which make use
of netdev_tx_sent_queue() internally, set __QUEUE_STATE_STACK_XOFF from
within the stack and would not fully fill the device's TX ring from
packet sockets with PACKET_QDISC_BYPASS enabled.

Instead, use a test without BQL bit so that bursts can be absorbed
into the NICs TX ring. Fix and code suggested by Eric Dumazet, thanks!

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-03 14:29:12 -04:00
Daniel Borkmann 0f97ede45e packet: report tx_dropped in packet_direct_xmit
Since commit 015f0688f5 ("net: net: add a core netdev->tx_dropped
counter"), we can now account for TX drops from within the core
stack instead of drivers.

Therefore, fix packet_direct_xmit() and increase drop count when we
encounter a problem before driver's xmit function was called (we do
not want to doubly account for it).

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-03 14:29:11 -04:00
Daniel Borkmann 43279500de packet: respect devices with LLTX flag in direct xmit
Quite often it can be useful to test with dummy or similar
devices as a blackhole sink for skbs. Such devices are only
equipped with a single txq, but marked as NETIF_F_LLTX as
they do not require locking their internal queues on xmit
(or implement locking themselves). Therefore, rather use
HARD_TX_{UN,}LOCK API, so that NETIF_F_LLTX will be respected.

trafgen mmap/TX_RING example against dummy device with config
foo: { fill(0xff, 64) } results in the following performance
improvements for such scenarios on an ordinary Core i7/2.80GHz:

Before:

 Performance counter stats for 'trafgen -i foo -o du0 -n100000000' (10 runs):

   160,975,944,159 instructions:k            #    0.55  insns per cycle          ( +-  0.09% )
   293,319,390,278 cycles:k                  #    0.000 GHz                      ( +-  0.35% )
       192,501,104 branch-misses:k                                               ( +-  1.63% )
               831 context-switches:k                                            ( +-  9.18% )
                 7 cpu-migrations:k                                              ( +-  7.40% )
            69,382 cache-misses:k            #    0.010 % of all cache refs      ( +-  2.18% )
       671,552,021 cache-references:k                                            ( +-  1.29% )

      22.856401569 seconds time elapsed                                          ( +-  0.33% )

After:

 Performance counter stats for 'trafgen -i foo -o du0 -n100000000' (10 runs):

   133,788,739,692 instructions:k            #    0.92  insns per cycle          ( +-  0.06% )
   145,853,213,256 cycles:k                  #    0.000 GHz                      ( +-  0.17% )
        59,867,100 branch-misses:k                                               ( +-  4.72% )
               384 context-switches:k                                            ( +-  3.76% )
                 6 cpu-migrations:k                                              ( +-  6.28% )
            70,304 cache-misses:k            #    0.077 % of all cache refs      ( +-  1.73% )
        90,879,408 cache-references:k                                            ( +-  1.35% )

      11.719372413 seconds time elapsed                                          ( +-  0.24% )

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-28 16:49:48 -04:00
Tom Herbert 61b905da33 net: Rename skb->rxhash to skb->hash
The packet hash can be considered a property of the packet, not just
on RX path.

This patch changes name of rxhash and l4_rxhash skbuff fields to be
hash and l4_hash respectively. This includes changing uses of the
field in the code which don't call the access functions.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-26 15:58:20 -04:00
Daniel Borkmann 52f1454f62 packet: allow to transmit +4 byte in TX_RING slot for VLAN case
Commit 57f89bfa21 ("network: Allow af_packet to transmit +4 bytes
for VLAN packets.") added the possibility for non-mmaped frames to
send extra 4 byte for VLAN header so the MTU increases from 1500 to
1504 byte, for example.

Commit cbd89acb9e ("af_packet: fix for sending VLAN frames via
packet_mmap") attempted to fix that for the mmap part but was
reverted as it caused regressions while using eth_type_trans()
on output path.

Lets just act analogous to 57f89bfa21 and add a similar logic
to TX_RING. We presume size_max as overcharged with +4 bytes and
later on after skb has been built by tpacket_fill_skb() check
for ETH_P_8021Q header on packets larger than normal MTU. Can
be easily reproduced with a slightly modified trafgen in mmap(2)
mode, test cases:

 { fill(0xff, 12) const16(0x8100) fill(0xff, <1504|1505>) }
 { fill(0xff, 12) const16(0x0806) fill(0xff, <1500|1501>) }

Note that we need to do the test right after tpacket_fill_skb()
as sockets can have PACKET_LOSS set where we would not fail but
instead just continue to traverse the ring.

Reported-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Ben Greear <greearb@candelatech.com>
Cc: Phil Sutter <phil@nwl.cc>
Tested-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-28 16:52:02 -05:00
Dan Carpenter d7cf0c34af af_packet: remove a stray tab in packet_set_ring()
At first glance it looks like there is a missing curly brace but
actually the code works the same either way.  I have adjusted the
indenting but left the code the same.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-18 18:02:25 -05:00
Daniel Borkmann 0fd5d57ba3 packet: check for ndo_select_queue during queue selection
Mathias reported that on an AMD Geode LX embedded board (ALiX)
with ath9k driver PACKET_QDISC_BYPASS, introduced in commit
d346a3fae3 ("packet: introduce PACKET_QDISC_BYPASS socket
option"), triggers a WARN_ON() coming from the driver itself
via 066dae93bd ("ath9k: rework tx queue selection and fix
queue stopping/waking").

The reason why this happened is that ndo_select_queue() call
is not invoked from direct xmit path i.e. for ieee80211 subsystem
that sets queue and TID (similar to 802.1d tag) which is being
put into the frame through 802.11e (WMM, QoS). If that is not
set, pending frame counter for e.g. ath9k can get messed up.

So the WARN_ON() in ath9k is absolutely legitimate. Generally,
the hw queue selection in ieee80211 depends on the type of
traffic, and priorities are set according to ieee80211_ac_numbers
mapping; working in a similar way as DiffServ only on a lower
layer, so that the AP can favour frames that have "real-time"
requirements like voice or video data frames.

Therefore, check for presence of ndo_select_queue() in netdev
ops and, if available, invoke it with a fallback handler to
__packet_pick_tx_queue(), so that driver such as bnx2x, ixgbe,
or mlx4 can still select a hw queue for transmission in
relation to the current CPU while e.g. ieee80211 subsystem
can make their own choices.

Reported-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-17 00:36:34 -05:00
Neil Horman 2d36097d26 af_packet: Add Queue mapping mode to af_packet fanout operation
This patch adds a queue mapping mode to the fanout operation of af_packet
sockets.  This allows user space af_packet users to better filter on flows
ingressing and egressing via a specific hardware queue, and avoids the potential
packet reordering that can occur when FANOUT_CPU is being used and irq affinity
varies.

Tested successfully by myself.  applies to net-next

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 17:35:50 -08:00
Daniel Borkmann 89770b0a69 net: introduce reciprocal_scale helper and convert users
As David Laight suggests, we shouldn't necessarily call this
reciprocal_divide() when users didn't requested a reciprocal_value();
lets keep the basic idea and call it reciprocal_scale(). More
background information on this topic can be found in [1].

Joint work with Hannes Frederic Sowa.

  [1] http://homepage.cs.uiowa.edu/~jones/bcd/divide.html

Suggested-by: David Laight <david.laight@aculab.com>
Cc: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 23:17:20 -08:00
Daniel Borkmann f337db64af random32: add prandom_u32_max and convert open coded users
Many functions have open coded a function that returns a random
number in range [0,N-1]. Under the assumption that we have a PRNG
such as taus113 with being well distributed in [0, ~0U] space,
we can implement such a function as uword t = (n*m')>>32, where
m' is a random number obtained from PRNG, n the right open interval
border and t our resulting random number, with n,m',t in u32 universe.

Lets go with Joe and simply call it prandom_u32_max(), although
technically we have an right open interval endpoint, but that we
have documented. Other users can further be migrated to the new
prandom_u32_max() function later on; for now, we need to make sure
to migrate reciprocal_divide() users for the reciprocal_divide()
follow-up fixup since their function signatures are going to change.

Joint work with Hannes Frederic Sowa.

Cc: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 23:17:20 -08:00
Daniel Borkmann f0d4eb29d1 packet: fix a couple of cppcheck warnings
Doesn't bring much, but also doesn't hurt us to fix 'em:

1) In tpacket_rcv() flush dcache page we can restirct the scope
   for start and end and remove one layer of indent.

2) In tpacket_destruct_skb() we can restirct the scope for ph.

3) In alloc_one_pg_vec_page() we can remove the NULL assignment
   and change spacing a bit.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 16:51:42 -08:00
Steffen Hurrle 342dfc306f net: add build-time checks for msg->msg_name size
This is a follow-up patch to f3d3342602 ("net: rework recvmsg
handler msg_name and msg_namelen logic").

DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.

Signed-off-by: Steffen Hurrle <steffen@hurrle.net>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-18 23:04:16 -08:00
Daniel Borkmann b013840810 packet: use percpu mmap tx frame pending refcount
In PF_PACKET's packet mmap(), we can avoid using one atomic_inc()
and one atomic_dec() call in skb destructor and use a percpu
reference count instead in order to determine if packets are
still pending to be sent out. Micro-benchmark with [1] that has
been slightly modified (that is, protcol = 0 in socket(2) and
bind(2)), example on a rather crappy testing machine; I expect
it to scale and have even better results on bigger machines:

./packet_mm_tx -s7000 -m7200 -z700000 em1, avg over 2500 runs:

With patch:    4,022,015 cyc
Without patch: 4,812,994 cyc

time ./packet_mm_tx -s64 -c10000000 em1 > /dev/null, stable:

With patch:
  real         1m32.241s
  user         0m0.287s
  sys          1m29.316s

Without patch:
  real         1m38.386s
  user         0m0.265s
  sys          1m35.572s

In function tpacket_snd(), it is okay to use packet_read_pending()
since in fast-path we short-circuit the condition already with
ph != NULL, since we have next frames to process. In case we have
MSG_DONTWAIT, we also do not execute this path as need_wait is
false here anyway, and in case of _no_ MSG_DONTWAIT flag, it is
okay to call a packet_read_pending(), because when we ever reach
that path, we're done processing outgoing frames anyway and only
look if there are skbs still outstanding to be orphaned. We can
stay lockless in this percpu counter since it's acceptable when we
reach this path for the sum to be imprecise first, but we'll level
out at 0 after all pending frames have reached the skb destructor
eventually through tx reclaim. When people pin a tx process to
particular CPUs, we expect overflows to happen in the reference
counter as on one CPU we expect heavy increase; and distributed
through ksoftirqd on all CPUs a decrease, for example. As
David Laight points out, since the C language doesn't define the
result of signed int overflow (i.e. rather than wrap, it is
allowed to saturate as a possible outcome), we have to use
unsigned int as reference count. The sum over all CPUs when tx
is complete will result in 0 again.

The BUG_ON() in tpacket_destruct_skb() we can remove as well. It
can _only_ be set from inside tpacket_snd() path and we made sure
to increase tx_ring.pending in any case before we called po->xmit(skb).
So testing for tx_ring.pending == 0 is not too useful. Instead, it
would rather have been useful to test if lower layers didn't orphan
the skb so that we're missing ring slots being put back to
TP_STATUS_AVAILABLE. But such a bug will be caught in user space
already as we end up realizing that we do not have any
TP_STATUS_AVAILABLE slots left anymore. Therefore, we're all set.

Btw, in case of RX_RING path, we do not make use of the pending
member, therefore we also don't need to use up any percpu memory
here. Also note that __alloc_percpu() already returns a zero-filled
percpu area, so initialization is done already.

  [1] http://wiki.ipxwarzone.com/index.php5?title=Linux_packet_mmap

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 16:17:12 -08:00
Daniel Borkmann 87a2fd286a packet: don't unconditionally schedule() in case of MSG_DONTWAIT
In tpacket_snd(), when we've discovered a first frame that is
not in status TP_STATUS_SEND_REQUEST, and return a NULL buffer,
we exit the send routine in case of MSG_DONTWAIT, since we've
finished traversing the mmaped send ring buffer and don't care
about pending frames.

While doing so, we still unconditionally call an expensive
schedule() in the packet_current_frame() "error" path, which
is unnecessary in this case since it's enough to just quit
the function.

Also, in case MSG_DONTWAIT is not set, we should rather test
for need_resched() first and do schedule() only if necessary
since meanwhile pending frames could already have finished
processing and called skb destructor.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 16:17:11 -08:00
Daniel Borkmann 902fefb82e packet: improve socket create/bind latency in some cases
Most people acquire PF_PACKET sockets with a protocol argument in
the socket call, e.g. libpcap does so with htons(ETH_P_ALL) for
all its sockets. Most likely, at some point in time a subsequent
bind() call will follow, e.g. in libpcap with ...

  memset(&sll, 0, sizeof(sll));
  sll.sll_family          = AF_PACKET;
  sll.sll_ifindex         = ifindex;
  sll.sll_protocol        = htons(ETH_P_ALL);

... as arguments. What happens in the kernel is that already
in socket() syscall, we install a proto hook via register_prot_hook()
if our protocol argument is != 0. Yet, in bind() we're almost
doing the same work by doing a unregister_prot_hook() with an
expensive synchronize_net() call in case during socket() the proto
was != 0, plus follow-up register_prot_hook() with a bound device
to it this time, in order to limit traffic we get.

In the case when the protocol and user supplied device index (== 0)
does not change from socket() to bind(), we can spare us doing
the same work twice. Similarly for re-binding to the same device
and protocol. For these scenarios, we can decrease create/bind
latency from ~7447us (sock-bind-2 case) to ~89us (sock-bind-1 case)
with this patch.

Alternatively, for the first case, if people care, they should
simply create their sockets with proto == 0 argument and define
the protocol during bind() as this saves a call to synchronize_net()
as well (sock-bind-3 case).

In all other cases, we're tied to user space behaviour we must not
change, also since a bind() is not strictly required. Thus, we need
the synchronize_net() to make sure no asynchronous packet processing
paths still refer to the previous elements of po->prot_hook.

In case of mmap()ed sockets, the workflow that includes bind() is
socket() -> setsockopt(<ring>) -> bind(). In that case, a pair of
{__unregister, register}_prot_hook is being called from setsockopt()
in order to install the new protocol receive handler. Thus, when
we call bind and can skip a re-hook, we have already previously
installed the new handler. For fanout, this is handled different
entirely, so we should be good.

Timings on an i7-3520M machine:

  * sock-bind-1:   89 us
  * sock-bind-2: 7447 us
  * sock-bind-3:   75 us

sock-bind-1:
  socket(PF_PACKET, SOCK_RAW, htons(ETH_P_IP)) = 3
  bind(3, {sa_family=AF_PACKET, proto=htons(ETH_P_IP), if=all(0),
           pkttype=PACKET_HOST, addr(0)={0, }, 20) = 0

sock-bind-2:
  socket(PF_PACKET, SOCK_RAW, htons(ETH_P_IP)) = 3
  bind(3, {sa_family=AF_PACKET, proto=htons(ETH_P_IP), if=lo(1),
           pkttype=PACKET_HOST, addr(0)={0, }, 20) = 0

sock-bind-3:
  socket(PF_PACKET, SOCK_RAW, 0) = 3
  bind(3, {sa_family=AF_PACKET, proto=htons(ETH_P_IP), if=lo(1),
           pkttype=PACKET_HOST, addr(0)={0, }, 20) = 0

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 16:17:11 -08:00
Weilong Chen d4dd8aeefd packet: fix "foo * bar" and "(foo*)" problems
Cleanup checkpatch errors.Specially,the second changed line
is exactly 80 columns long.

Signed-off-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-31 13:38:41 -05:00
Atzm Watanabe a0cdfcf393 packet: deliver VLAN TPID to userspace
This enables userspace to get VLAN TPID as well as the VLAN TCI.

Signed-off-by: Atzm Watanabe <atzm@stratosphere.co.jp>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18 00:36:16 -05:00
Atzm Watanabe e4d26f4b08 packet: fill the gap of TPACKET_ALIGNMENT with zeros
struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
Explicitly defining and zeroing the gap of this makes additional changes
easier.

Signed-off-by: Atzm Watanabe <atzm@stratosphere.co.jp>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18 00:36:16 -05:00
Atzm Watanabe 51846355bc packet: make aligned size of struct tpacket{2,3}_hdr clear
struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
We may add members to them until current aligned size without forcing
userspace to call getsockopt(..., PACKET_HDRLEN, ...).

Signed-off-by: Atzm Watanabe <atzm@stratosphere.co.jp>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18 00:36:16 -05:00
Tom Herbert 3958afa1b2 net: Change skb_get_rxhash to skb_get_hash
Changing name of function as part of making the hash in skbuff to be
generic property, not just for receive path.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-17 16:36:21 -05:00
Li Zhong 1cbac01052 packet: fix using smp_processor_id() in preemptible code
This patches fixes the following warning by replacing smp_processor_id()
with raw_smp_processor_id():

[   11.120893] BUG: using smp_processor_id() in preemptible [00000000] code: arping/3510
[   11.120913] caller is .packet_sendmsg+0xc14/0xe68
[   11.120920] CPU: 13 PID: 3510 Comm: arping Not tainted 3.13.0-rc3-next-20131211-dirty #1
[   11.120926] Call Trace:
[   11.120932] [c0000001f803f6f0] [c0000000000138dc] .show_stack+0x110/0x25c (unreliable)
[   11.120942] [c0000001f803f7e0] [c00000000083dd24] .dump_stack+0xa0/0x37c
[   11.120951] [c0000001f803f870] [c000000000493fd4] .debug_smp_processor_id+0xfc/0x12c
[   11.120959] [c0000001f803f900] [c0000000007eba78] .packet_sendmsg+0xc14/0xe68
[   11.120968] [c0000001f803fa80] [c000000000700968] .sock_sendmsg+0xa0/0xe0
[   11.120975] [c0000001f803fbf0] [c0000000007014d8] .SyS_sendto+0x100/0x148
[   11.120983] [c0000001f803fd60] [c0000000006fff10] .SyS_socketcall+0x1c4/0x2e8
[   11.120990] [c0000001f803fe30] [c00000000000a1e4] syscall_exit+0x0/0x9c

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-14 01:04:13 -05:00
Daniel Borkmann d346a3fae3 packet: introduce PACKET_QDISC_BYPASS socket option
This patch introduces a PACKET_QDISC_BYPASS socket option, that
allows for using a similar xmit() function as in pktgen instead
of taking the dev_queue_xmit() path. This can be very useful when
PF_PACKET applications are required to be used in a similar
scenario as pktgen, but with full, flexible packet payload that
needs to be provided, for example.

On default, nothing changes in behaviour for normal PF_PACKET
TX users, so everything stays as is for applications. New users,
however, can now set PACKET_QDISC_BYPASS if needed to prevent
own packets from i) reentering packet_rcv() and ii) to directly
push the frame to the driver.

In doing so we can increase pps (here 64 byte packets) for
PF_PACKET a bit:

  # CPUs -- QDISC_BYPASS   -- qdisc path -- qdisc path[**]
  1 CPU  ==  1,509,628 pps --  1,208,708 --  1,247,436
  2 CPUs ==  3,198,659 pps --  2,536,012 --  1,605,779
  3 CPUs ==  4,787,992 pps --  3,788,740 --  1,735,610
  4 CPUs ==  6,173,956 pps --  4,907,799 --  1,909,114
  5 CPUs ==  7,495,676 pps --  5,956,499 --  2,014,422
  6 CPUs ==  9,001,496 pps --  7,145,064 --  2,155,261
  7 CPUs == 10,229,776 pps --  8,190,596 --  2,220,619
  8 CPUs == 11,040,732 pps --  9,188,544 --  2,241,879
  9 CPUs == 12,009,076 pps -- 10,275,936 --  2,068,447
 10 CPUs == 11,380,052 pps -- 11,265,337 --  1,578,689
 11 CPUs == 11,672,676 pps -- 11,845,344 --  1,297,412
 [...]
 20 CPUs == 11,363,192 pps -- 11,014,933 --  1,245,081

 [**]: qdisc path with packet_rcv(), how probably most people
       seem to use it (hopefully not anymore if not needed)

The test was done using a modified trafgen, sending a simple
static 64 bytes packet, on all CPUs.  The trick in the fast
"qdisc path" case, is to avoid reentering packet_rcv() by
setting the RAW socket protocol to zero, like:
socket(PF_PACKET, SOCK_RAW, 0);

Tradeoffs are documented as well in this patch, clearly, if
queues are busy, we will drop more packets, tc disciplines are
ignored, and these packets are not visible to taps anymore. For
a pktgen like scenario, we argue that this is acceptable.

The pointer to the xmit function has been placed in packet
socket structure hole between cached_dev and prot_hook that
is hot anyway as we're working on cached_dev in each send path.

Done in joint work together with Jesper Dangaard Brouer.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09 20:23:33 -05:00
David S. Miller 34f9f43710 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge 'net' into 'net-next' to get the AF_PACKET bug fix that
Daniel's direct transmit changes depend upon.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09 20:20:14 -05:00
Daniel Borkmann 66e56cd46b packet: fix send path when running with proto == 0
Commit e40526cb20 introduced a cached dev pointer, that gets
hooked into register_prot_hook(), __unregister_prot_hook() to
update the device used for the send path.

We need to fix this up, as otherwise this will not work with
sockets created with protocol = 0, plus with sll_protocol = 0
passed via sockaddr_ll when doing the bind.

So instead, assign the pointer directly. The compiler can inline
these helper functions automagically.

While at it, also assume the cached dev fast-path as likely(),
and document this variant of socket creation as it seems it is
not widely used (seems not even the author of TX_RING was aware
of that in his reference example [1]). Tested with reproducer
from e40526cb20.

 [1] http://wiki.ipxwarzone.com/index.php5?title=Linux_packet_mmap#Example

Fixes: e40526cb20 ("packet: fix use after free race in send path when dev is released")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Tested-by: Salam Noureddine <noureddine@aristanetworks.com>
Tested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09 20:09:20 -05:00
Duan Jiong 22781a5b9c packet: use macro GET_PBDQC_FROM_RB to simplify the codes
Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 12:51:39 -05:00
Veaceslav Falico ec6f809ff6 af_packet: block BH in prb_shutdown_retire_blk_timer()
Currently we're using plain spin_lock() in prb_shutdown_retire_blk_timer(),
however the timer might fire right in the middle and thus try to re-aquire
the same spinlock, leaving us in a endless loop.

To fix that, use the spin_lock_bh() to block it.

Fixes: f6fb8f100b ("af-packet: TPACKET_V3 flexible buffer implementation.")
CC: "David S. Miller" <davem@davemloft.net>
CC: Daniel Borkmann <dborkman@redhat.com>
CC: Willem de Bruijn <willemb@google.com>
CC: Phil Sutter <phil@nwl.cc>
CC: Eric Dumazet <edumazet@google.com>
Reported-by: Jan Stancek <jstancek@redhat.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-29 16:11:08 -05:00
Daniel Borkmann e40526cb20 packet: fix use after free race in send path when dev is released
Salam reported a use after free bug in PF_PACKET that occurs when
we're sending out frames on a socket bound device and suddenly the
net device is being unregistered. It appears that commit 827d9780
introduced a possible race condition between {t,}packet_snd() and
packet_notifier(). In the case of a bound socket, packet_notifier()
can drop the last reference to the net_device and {t,}packet_snd()
might end up suddenly sending a packet over a freed net_device.

To avoid reverting 827d9780 and thus introducing a performance
regression compared to the current state of things, we decided to
hold a cached RCU protected pointer to the net device and maintain
it on write side via bind spin_lock protected register_prot_hook()
and __unregister_prot_hook() calls.

In {t,}packet_snd() path, we access this pointer under rcu_read_lock
through packet_cached_dev_get() that holds reference to the device
to prevent it from being freed through packet_notifier() while
we're in send path. This is okay to do as dev_put()/dev_hold() are
per-cpu counters, so this should not be a performance issue. Also,
the code simplifies a bit as we don't need need_rls_dev anymore.

Fixes: 827d978037 ("af-packet: Use existing netdev reference for bound sockets.")
Reported-by: Salam Noureddine <noureddine@aristanetworks.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Salam Noureddine <noureddine@aristanetworks.com>
Cc: Ben Greear <greearb@candelatech.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-21 13:09:43 -05:00
Hannes Frederic Sowa f3d3342602 net: rework recvmsg handler msg_name and msg_namelen logic
This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
	msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-20 21:52:30 -05:00
Daniel Borkmann f55d112e52 net: packet: use reciprocal_divide in fanout_demux_hash
Instead of hard-coding reciprocal_divide function, use the inline
function from reciprocal_div.h.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-29 16:43:29 -04:00
Daniel Borkmann 5df0ddfbc9 net: packet: add randomized fanout scheduler
We currently allow for different fanout scheduling policies in pf_packet
such as scheduling by skb's rxhash, round-robin, by cpu, and rollover.
Also allow for a random, equidistributed selection of the socket from the
fanout process group.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-29 16:43:29 -04:00
David S. Miller b05930f5d1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/wireless/iwlwifi/pcie/trans.c
	include/linux/inetdevice.h

The inetdevice.h conflict involves moving the IPV4_DEVCONF values
into a UAPI header, overlapping additions of some new entries.

The iwlwifi conflict is a context overlap.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-26 16:37:08 -04:00
Willem de Bruijn 8bcdeaff5e packet: restore packet statistics tp_packets to include drops
getsockopt PACKET_STATISTICS returns tp_packets + tp_drops. Commit
ee80fbf301 ("packet: account statistics only in tpacket_stats_u")
cleaned up the getsockopt PACKET_STATISTICS code.
This also changed semantics. Historically, tp_packets included
tp_drops on return. The commit removed the line that adds tp_drops
into tp_packets.

This patch reinstates the old semantics.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-20 17:23:58 -07:00