linux-toradex.git/net/packet, branch v4.4.23

packet: Use symmetric hash for PACKET_FANOUT_HASH.

2016-07-27T16:47:31+00:00

[ Upstream commit eb70db8756717b90c01ccc765fdefc4dd969fc74 ]

People who use PACKET_FANOUT_HASH want a symmetric hash, meaning that
they want packets going in both directions on a flow to hash to the
same bucket.

The core kernel SKB hash became non-symmetric when the ipv6 flow label
and other entities were incorporated into the standard flow hash order
to increase entropy.

But there are no users of PACKET_FANOUT_HASH who want an assymetric
hash, they all want a symmetric one.

Therefore, use the flow dissector to compute a flat symmetric hash
over only the protocol, addresses and ports.  This hash does not get
installed into and override the normal skb hash, so this change has
no effect whatsoever on the rest of the stack.

Reported-by: Eric Leblond 
Tested-by: Eric Leblond 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

packet: fix heap info leak in PACKET_DIAG_MCLIST sock_diag interface

2016-05-19T00:06:35+00:00

[ Upstream commit 309cf37fe2a781279b7675d4bb7173198e532867 ]

Because we miss to wipe the remainder of i->addr[] in packet_mc_add(),
pdiag_put_mclist() leaks uninitialized heap bytes via the
PACKET_DIAG_MCLIST netlink attribute.

Fix this by explicitly memset(0)ing the remaining bytes in i->addr[].

Fixes: eea68e2f1a00 ("packet: Report socket mclist info via diag module")
Signed-off-by: Mathias Krause 
Cc: Eric W. Biederman 
Cc: Pavel Emelyanov 
Acked-by: Pavel Emelyanov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

packet: validate variable length ll headers

2016-04-20T06:42:01+00:00

[ Upstream commit 9ed988cd591500c040b2a6257bc68543e08ceeef ]

Replace link layer header validation check ll_header_truncate with
more generic dev_validate_header.

Validation based on hard_header_len incorrectly drops valid packets
in variable length protocols, such as AX25. dev_validate_header
calls header_ops.validate for such protocols to ensure correctness
below hard_header_len.

See also http://comments.gmane.org/gmane.linux.network/401064

Fixes 9c7077622dd9 ("packet: make packet_snd fail on len smaller than l2 header")
Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

packet: Allow packets with only a header (but no payload)

2015-11-30T03:17:17+00:00

Commit 9c7077622dd91 ("packet: make packet_snd fail on len smaller
than l2 header") added validation for the packet size in packet_snd.
This change enforces that every packet needs a header (with at least
hard_header_len bytes) plus a payload with at least one byte. Before
this change the payload was optional.

This fixes PPPoE connections which do not have a "Service" or
"Host-Uniq" configured (which is violating the spec, but is still
widely used in real-world setups). Those are currently failing with the
following message: "pppd: packet size is too short (24 <= 24)"

Signed-off-by: Martin Blumenstingl 
Signed-off-by: David S. Miller

packet: Use PAGE_ALIGNED macro

2015-11-17T20:25:44+00:00

Use PAGE_ALIGNED(...) instead of open-coding it.

Signed-off-by: Tobias Klauser 
Signed-off-by: David S. Miller

packet: Don't check frames_per_block against negative values

2015-11-17T20:25:44+00:00

rb->frames_per_block is an unsigned int, thus can never be negative.

Also fix spacing in the calculation of frames_per_block.

Signed-off-by: Tobias Klauser 
Signed-off-by: David S. Miller

packet: fix tpacket_snd max frame len

2015-11-15T23:00:35+00:00

Since it's introduction in commit 69e3c75f4d54 ("net: TX_RING and
packet mmap"), TX_RING could be used from SOCK_DGRAM and SOCK_RAW
side. When used with SOCK_DGRAM only, the size_max > dev->mtu +
reserve check should have reserve as 0, but currently, this is
unconditionally set (in it's original form as dev->hard_header_len).

I think this is not correct since tpacket_fill_skb() would then
take dev->mtu and dev->hard_header_len into account for SOCK_DGRAM,
the extra VLAN_HLEN could be possible in both cases. Presumably, the
reserve code was copied from packet_snd(), but later on missed the
check. Make it similar as we have it in packet_snd().

Fixes: 69e3c75f4d54 ("net: TX_RING and packet mmap")
Signed-off-by: Daniel Borkmann 
Acked-by: Willem de Bruijn 
Signed-off-by: David S. Miller

packet: infer protocol from ethernet header if unset

2015-11-15T23:00:35+00:00

In case no struct sockaddr_ll has been passed to packet
socket's sendmsg() when doing a TX_RING flush run, then
skb->protocol is set to po->num instead, which is the protocol
passed via socket(2)/bind(2).

Applications only xmitting can go the path of allocating the
socket as socket(PF_PACKET, , 0) and do a bind(2) on the
TX_RING with sll_protocol of 0. That way, register_prot_hook()
is neither called on creation nor on bind time, which saves
cycles when there's no interest in capturing anyway.

That leaves us however with po->num 0 instead and therefore
the TX_RING flush run sets skb->protocol to 0 as well. Eric
reported that this leads to problems when using tools like
trafgen over bonding device. I.e. the bonding's hash function
could invoke the kernel's flow dissector, which depends on
skb->protocol being properly set. In the current situation, all
the traffic is then directed to a single slave.

Fix it up by inferring skb->protocol from the Ethernet header
when not set and we have ARPHRD_ETHER device type. This is only
done in case of SOCK_RAW and where we have a dev->hard_header_len
length. In case of ARPHRD_ETHER devices, this is guaranteed to
cover ETH_HLEN, and therefore being accessed on the skb after
the skb_store_bits().

Reported-by: Eric Dumazet 
Signed-off-by: Daniel Borkmann 
Acked-by: Willem de Bruijn 
Signed-off-by: David S. Miller

packet: only allow extra vlan len on ethernet devices

2015-11-15T23:00:35+00:00

Packet sockets can be used by various net devices and are not
really restricted to ARPHRD_ETHER device types. However, when
currently checking for the extra 4 bytes that can be transmitted
in VLAN case, our assumption is that we generally probe on
ARPHRD_ETHER devices. Therefore, before looking into Ethernet
header, check the device type first.

This also fixes the issue where non-ARPHRD_ETHER devices could
have no dev->hard_header_len in TX_RING SOCK_RAW case, and thus
the check would test unfilled linear part of the skb (instead
of non-linear).

Fixes: 57f89bfa2140 ("network: Allow af_packet to transmit +4 bytes for VLAN packets.")
Fixes: 52f1454f629f ("packet: allow to transmit +4 byte in TX_RING slot for VLAN case")
Signed-off-by: Daniel Borkmann 
Acked-by: Willem de Bruijn 
Signed-off-by: David S. Miller

packet: always probe for transport header

2015-11-15T23:00:35+00:00

We concluded that the skb_probe_transport_header() should better be
called unconditionally. Avoiding the call into the flow dissector has
also not really much to do with the direct xmit mode.

While it seems that only virtio_net code makes use of GSO from non
RX/TX ring packet socket paths, we should probe for a transport header
nevertheless before they hit devices.

Reference: http://thread.gmane.org/gmane.linux.network/386173/
Signed-off-by: Daniel Borkmann 
Acked-by: Jason Wang 
Signed-off-by: David S. Miller