linux-stable.git/net/ipv4/af_inet.c, branch linux-4.7.y

ipv4: Fix non-initialized TTL when CONFIG_SYSCTL=n

2016-05-23T21:32:06+00:00

Commit fa50d974d104 ("ipv4: Namespaceify ip_default_ttl sysctl knob")
moves the default TTL assignment, and as side-effect IPv4 TTL now
has a default value only if sysctl support is enabled (CONFIG_SYSCTL=y).

The sysctl_ip_default_ttl is fundamental for IP to work properly,
as it provides the TTL to be used as default. The defautl TTL may be
used in ip_selected_ttl, through the following flow:

  ip_select_ttl
    ip4_dst_hoplimit
      net->ipv4.sysctl_ip_default_ttl

This commit fixes the issue by assigning net->ipv4.sysctl_ip_default_ttl
in net_init_net, called during ipv4's initialization.

Without this commit, a kernel built without sysctl support will send
all IP packets with zero TTL (unless a TTL is explicitly set, e.g.
with setsockopt).

Given a similar issue might appear on the other knobs that were
namespaceify, this commit also moves them.

Fixes: fa50d974d104 ("ipv4: Namespaceify ip_default_ttl sysctl knob")
Signed-off-by: Ezequiel Garcia 
Signed-off-by: David S. Miller

ip4ip6: Support for GSO/GRO

2016-05-20T22:03:17+00:00

Signed-off-by: Tom Herbert 
Signed-off-by: David S. Miller

net: define gso types for IPx over IPv4 and IPv6

2016-05-20T22:03:15+00:00

This patch defines two new GSO definitions SKB_GSO_IPXIP4 and
SKB_GSO_IPXIP6 along with corresponding NETIF_F_GSO_IPXIP4 and
NETIF_F_GSO_IPXIP6. These are used to described IP in IP
tunnel and what the outer protocol is. The inner protocol
can be deduced from other GSO types (e.g. SKB_GSO_TCPV4 and
SKB_GSO_TCPV6). The GSO types of SKB_GSO_IPIP and SKB_GSO_SIT
are removed (these are both instances of SKB_GSO_IPXIP4).
SKB_GSO_IPXIP6 will be used when support for GSO with IP
encapsulation over IPv6 is added.

Signed-off-by: Tom Herbert 
Acked-by: Jeff Kirsher 
Signed-off-by: David S. Miller

gso: Remove arbitrary checks for unsupported GSO

2016-05-20T22:03:15+00:00

In several gso_segment functions there are checks of gso_type against
a seemingly arbitrary list of SKB_GSO_* flags. This seems like an
attempt to identify unsupported GSO types, but since the stack is
the one that set these GSO types in the first place this seems
unnecessary to do. If a combination isn't valid in the first
place that stack should not allow setting it.

This is a code simplication especially for add new GSO types.

Signed-off-by: Tom Herbert 
Signed-off-by: David S. Miller

GSO: Support partial segmentation offload

2016-04-14T20:23:41+00:00

This patch adds support for something I am referring to as GSO partial.
The basic idea is that we can support a broader range of devices for
segmentation if we use fixed outer headers and have the hardware only
really deal with segmenting the inner header.  The idea behind the naming
is due to the fact that everything before csum_start will be fixed headers,
and everything after will be the region that is handled by hardware.

With the current implementation it allows us to add support for the
following GSO types with an inner TSO_MANGLEID or TSO6 offload:
NETIF_F_GSO_GRE
NETIF_F_GSO_GRE_CSUM
NETIF_F_GSO_IPIP
NETIF_F_GSO_SIT
NETIF_F_UDP_TUNNEL
NETIF_F_UDP_TUNNEL_CSUM

In the case of hardware that already supports tunneling we may be able to
extend this further to support TSO_TCPV4 without TSO_MANGLEID if the
hardware can support updating inner IPv4 headers.

Signed-off-by: Alexander Duyck 
Signed-off-by: David S. Miller

GRO: Add support for TCP with fixed IPv4 ID field, limit tunnel IP ID values

2016-04-14T20:23:41+00:00

This patch does two things.

First it allows TCP to aggregate TCP frames with a fixed IPv4 ID field.  As
a result we should now be able to aggregate flows that were converted from
IPv6 to IPv4.  In addition this allows us more flexibility for future
implementations of segmentation as we may be able to use a fixed IP ID when
segmenting the flow.

The second thing this does is that it places limitations on the outer IPv4
ID header in the case of tunneled frames.  Specifically it forces the IP ID
to be incrementing by 1 unless the DF bit is set in the outer IPv4 header.
This way we can avoid creating overlapping series of IP IDs that could
possibly be fragmented if the frame goes through GRO and is then
resegmented via GSO.

Signed-off-by: Alexander Duyck 
Signed-off-by: David S. Miller

GSO: Add GSO type for fixed IPv4 ID

2016-04-14T20:23:40+00:00

This patch adds support for TSO using IPv4 headers with a fixed IP ID
field.  This is meant to allow us to do a lossless GRO in the case of TCP
flows that use a fixed IP ID such as those that convert IPv6 header to IPv4
headers.

In addition I am adding a feature that for now I am referring to TSO with
IP ID mangling.  Basically when this flag is enabled the device has the
option to either output the flow with incrementing IP IDs or with a fixed
IP ID regardless of what the original IP ID ordering was.  This is useful
in cases where the DF bit is set and we do not care if the original IP ID
value is maintained.

Signed-off-by: Alexander Duyck 
Signed-off-by: David S. Miller

net: introduce lockdep_is_held and update various places to use it

2016-04-07T20:44:14+00:00

The socket is either locked if we hold the slock spin_lock for
lock_sock_fast and unlock_sock_fast or we own the lock (sk_lock.owned
!= 0). Check for this and at the same time improve that the current
thread/cpu is really holding the lock.

Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

udp: enable MSG_PEEK at non-zero offset

2016-04-05T20:29:37+00:00

Enable peeking at UDP datagrams at the offset specified with socket
option SOL_SOCKET/SO_PEEK_OFF. Peek at any datagram in the queue, up
to the end of the given datagram.

Implement the SO_PEEK_OFF semantics introduced in commit ef64a54f6e55
("sock: Introduce the SO_PEEK_OFF sock option"). Increase the offset
on peek, decrease it on regular reads.

When peeking, always checksum the packet immediately, to avoid
recomputation on subsequent peeks and final read.

The socket lock is not held for the duration of udp_recvmsg, so
peek and read operations can run concurrently. Only the last store
to sk_peek_off is preserved.

Signed-off-by: Sam Kumar 
Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller

net: ipv4: Fix truncated timestamp returned by inet_current_timestamp()

2016-03-22T02:56:38+00:00

The millisecond timestamps returned by the function is
converted to network byte order by making a call to htons().
htons() only returns __be16 while __be32 is required here.

This was identified by the sparse warning from the buildbot:
net/ipv4/af_inet.c:1405:16: sparse: incorrect type in return
			    expression (different base types)
net/ipv4/af_inet.c:1405:16: expected restricted __be32
net/ipv4/af_inet.c:1405:16: got restricted __be16 [usertype] 

Change the function to use htonl() to return the correct __be32 type
instead so that the millisecond value doesn't get truncated.

Signed-off-by: Deepa Dinamani 
Cc: "David S. Miller" 
Cc: Alexey Kuznetsov 
Cc: Hideaki YOSHIFUJI 
Cc: James Morris 
Cc: Patrick McHardy 
Cc: Arnd Bergmann 
Fixes: 822c868532ca ("net: ipv4: Convert IP network timestamps to be y2038 safe")
Reported-by: Fengguang Wu  [0-day test robot]
Signed-off-by: David S. Miller