linux-stable.git/net/ipv4/arp.c, branch linux-4.1.y

ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY

2018-03-01T03:09:44+00:00

[ Upstream commit cd9ff4de0107c65d69d02253bb25d6db93c3dbc1 ]

Map all lookup neigh keys to INADDR_ANY for loopback/point-to-point devices
to avoid making an entry for every remote ip the device needs to talk to.

This used the be the old behavior but became broken in a263b3093641f
(ipv4: Make neigh lookups directly in output packet path) and later removed
in 0bb4087cbec0 (ipv4: Fix neigh lookup keying over loopback/point-to-point
devices) because it was broken.

Signed-off-by: Jim Westfall 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

NET: Fix /proc/net/arp for AX.25

2017-06-26T02:02:20+00:00

[ Upstream commit 4872e57c812dd312bf8193b5933fa60585cda42f ]

When sending ARP requests over AX.25 links the hwaddress in the neighbour
cache are not getting initialized.  For such an incomplete arp entry
ax2asc2 will generate an empty string resulting in /proc/net/arp output
like the following:

$ cat /proc/net/arp
IP address       HW type     Flags       HW address            Mask     Device
192.168.122.1    0x1         0x2         52:54:00:00:5d:5f     *        ens3
172.20.1.99      0x3         0x0              *        bpq0

The missing field will confuse the procfs parsing of arp(8) resulting in
incorrect output for the device such as the following:

$ arp
Address                  HWtype  HWaddress           Flags Mask            Iface
gateway                  ether   52:54:00:00:5d:5f   C                     ens3
172.20.1.99                      (incomplete)                              ens3

This changes the content of /proc/net/arp to:

$ cat /proc/net/arp
IP address       HW type     Flags       HW address            Mask     Device
172.20.1.99      0x3         0x0         *                     *        bpq0
192.168.122.1    0x1         0x2         52:54:00:00:5d:5f     *        ens3

To do so it change ax2asc to put the string "*" in buf for a NULL address
argument.  Finally the HW address field is left aligned in a 17 character
field (the length of an ethernet HW address in the usual hex notation) for
readability.

Signed-off-by: Ralf Baechle 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

netfilter: Pass socket pointer down through okfn().

2015-04-07T19:25:55+00:00

On the output paths in particular, we have to sometimes deal with two
socket contexts.  First, and usually skb->sk, is the local socket that
generated the frame.

And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.

We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.

The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device.  We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.

Signed-off-by: David S. Miller

ipv4: coding style: comparison for inequality with NULL

2015-04-03T16:11:15+00:00

The ipv4 code uses a mixture of coding styles. In some instances check
for non-NULL pointer is done as x != NULL and sometimes as x. x is
preferred according to checkpatch and this patch makes the code
consistent by adopting the latter form.

No changes detected by objdiff.

Signed-off-by: Ian Morris 
Signed-off-by: David S. Miller

ipv4: coding style: comparison for equality with NULL

2015-04-03T16:11:15+00:00

The ipv4 code uses a mixture of coding styles. In some instances check
for NULL pointer is done as x == NULL and sometimes as !x. !x is
preferred according to checkpatch and this patch makes the code
consistent by adopting the latter form.

No changes detected by objdiff.

Signed-off-by: Ian Morris 
Signed-off-by: David S. Miller

neigh: Factor out ___neigh_lookup_noref

2015-03-04T05:23:23+00:00

While looking at the mpls code I found myself writing yet another
version of neigh_lookup_noref.  We currently have __ipv4_lookup_noref
and __ipv6_lookup_noref.

So to make my work a little easier and to make it a smidge easier to
verify/maintain the mpls code in the future I stopped and wrote
___neigh_lookup_noref.  Then I rewote __ipv4_lookup_noref and
__ipv6_lookup_noref in terms of this new function.  I tested my new
version by verifying that the same code is generated in
ip_finish_output2 and ip6_finish_output2 where these functions are
inlined.

To get to ___neigh_lookup_noref I added a new neighbour cache table
function key_eq.  So that the static size of the key would be
available.

I also added __neigh_lookup_noref for people who want to to lookup
a neighbour table entry quickly but don't know which neibhgour table
they are going to look up.

Signed-off-by: "Eric W. Biederman" 
Signed-off-by: David S. Miller

neigh: Don't require dst in neigh_hh_init

2015-03-02T21:43:41+00:00

- Add protocol to neigh_tbl so that dst->ops->protocol is not needed
- Acquire the device from neigh->dev

This results in a neigh_hh_init that will cache the samve values
regardless of the packets flowing through it.

Signed-off-by: "Eric W. Biederman" 
Signed-off-by: David S. Miller

arp: Kill arp_find

2015-03-02T21:43:41+00:00

There are no more callers so kill this function.

Signed-off-by: "Eric W. Biederman" 
Signed-off-by: David S. Miller

arp: Remove special case to give AX25 it's open arp operations.

2015-03-02T21:43:40+00:00

The special case has been pushed out into ax25_neigh_construct so there
is no need to keep this code in arp.c

Signed-off-by: "Eric W. Biederman" 
Signed-off-by: David S. Miller

neigh: remove dynamic neigh table registration support

2014-11-11T20:23:54+00:00

Currently there are only three neigh tables in the whole kernel:
arp table, ndisc table and decnet neigh table. What's more,
we don't support registering multiple tables per family.
Therefore we can just make these tables statically built-in.

Cc: David S. Miller 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller