linux-stable.git/net/ipv4/af_inet.c, branch linux-4.8.y

GSO: Reload iph after pskb_may_pull

2016-12-10T18:09:40+00:00

[ Upstream commit a510887824171ad260cc4a2603396c6247fdd091 ]

As it may get stale and lead to use after free.

Acked-by: Eric Dumazet 
Cc: Alexander Duyck 
Cc: Andrey Konovalov 
Fixes: cbc53e08a793 ("GSO: Add GSO type for fixed IPv4 ID")
Signed-off-by: Arnaldo Carvalho de Melo 
Acked-by: Alexander Duyck 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: add recursion limit to GRO

2016-11-15T06:48:52+00:00

[ Upstream commit fcd91dd449867c6bfe56a81cabba76b829fd05cd ]

Currently, GRO can do unlimited recursion through the gro_receive
handlers.  This was fixed for tunneling protocols by limiting tunnel GRO
to one level with encap_mark, but both VLAN and TEB still have this
problem.  Thus, the kernel is vulnerable to a stack overflow, if we
receive a packet composed entirely of VLAN headers.

This patch adds a recursion counter to the GRO layer to prevent stack
overflow.  When a gro_receive function hits the recursion limit, GRO is
aborted for this skb and it is processed normally.  This recursion
counter is put in the GRO CB, but could be turned into a percpu counter
if we run out of space in the CB.

Thanks to Vladimír Beneš  for the initial bug report.

Fixes: CVE-2016-7039
Fixes: 9b174d88c257 ("net: Add Transparent Ethernet Bridging GRO support.")
Fixes: 66e5133f19e9 ("vlan: Add GRO support for non hardware accelerated vlan")
Signed-off-by: Sabrina Dubroca 
Reviewed-by: Jiri Benc 
Acked-by: Hannes Frederic Sowa 
Acked-by: Tom Herbert 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: af_inet: make it explicitly non-modular

2016-07-12T05:44:26+00:00

The Makefile controlling compilation of this file is obj-y,
meaning that it currently is never being built as a module.

Since MODULE_ALIAS is a no-op for non-modular code, we can simply
remove the MODULE_ALIAS_NETPROTO variant used here.

We replace module.h with kmod.h since the file does make use of
request_module() in order to load other modules from here.

We don't have to worry about init.h coming in via the removed
module.h since the file explicitly includes init.h already.

Cc: "David S. Miller" 
Cc: Alexey Kuznetsov 
Cc: James Morris 
Cc: Hideaki YOSHIFUJI 
Cc: Patrick McHardy 
Cc: netdev@vger.kernel.org
Signed-off-by: Paul Gortmaker 
Signed-off-by: David S. Miller

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