Recompile IP options since IPCB may not be valid anymore when
ipv4_link_failure is called from arp_error_report.
Refer to the commit 3da1ed7ac3 ("net: avoid use IPCB in cipso_v4_error")
and the commit before that (9ef6b42ad6) for a similar issue.
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit e21db6f69a ("tcp: track total bytes delivered with ECN CE marks")
core TCP stack does a very good job tracking ECN signals.
The "sender's best estimate of CE information" Yuchung mentioned in his
patch is indeed the best we can do.
DCTCP can use tp->delivered_ce and tp->delivered to not duplicate the logic,
and use the existing best estimate.
This solves some problems, since current DCTCP logic does not deal with losses
and/or GRO or ack aggregation very well.
This also removes a dubious use of inet_csk(sk)->icsk_ack.rcv_mss
(this should have been tp->mss_cache), and a 64 bit divide.
Finally, we can see that the DCTCP logic, calling dctcp_update_alpha() for
every ACK could be done differently, calling it only once per RTT.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Lawrence Brakmo <brakmo@fb.com>
Cc: Abdul Kabbani <akabbani@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No need to have separate modules for this.
before:
text data bss dec filename
2038 1168 0 3206 net/ipv4/netfilter/ipt_MASQUERADE.ko
1526 1024 0 2550 net/ipv6/netfilter/ip6t_MASQUERADE.ko
after:
text data bss dec filename
2521 1296 0 3817 net/netfilter/xt_MASQUERADE.ko
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Both are now implemented by nf_nat_masquerade.c, so no need to keep
different headers.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Remove not useful protocol version check in gue_udp_recv since just
gue version 0 can hit that code. Moreover remove duplicated hdrlen
computation
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
gue tunnels run iptunnel_pull_offloads on received skbs. This can
determine a possible use-after-free accessing guehdr pointer since
the packet will be 'uncloned' running pskb_expand_head if it is a
cloned gso skb (e.g if the packet has been sent though a veth device)
Fixes: a09a4c8dd1 ("tunnels: Remove encapsulation offloads on decap")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Govindarajulu reported a regression with Network Manager which sends an
RTA_GATEWAY attribute with the address set to 0. Fixup the handling of
RTA_GATEWAY to only set fc_gw_family if the gateway address is actually
set.
Fixes: f35b794b3b ("ipv4: Prepare fib_config for IPv6 gateway")
Reported-by: Govindarajulu Varadarajan <govind.varadar@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
erspan tunnels run __iptunnel_pull_header on received skbs to remove
gre and erspan headers. This can determine a possible use-after-free
accessing pkt_md pointer in erspan_rcv since the packet will be 'uncloned'
running pskb_expand_head if it is a cloned gso skb (e.g if the packet has
been sent though a veth device). Fix it resetting pkt_md pointer after
__iptunnel_pull_header
Fixes: 1d7e2ed22f ("net: erspan: refactor existing erspan code")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for RTA_VIA and allow an IPv6 nexthop for v4 routes:
$ ip ro add 172.16.1.0/24 via inet6 2001:db8::1 dev eth0
$ ip ro ls
...
172.16.1.0/24 via inet6 2001:db8::1 dev eth0
For convenience and simplicity, userspace can use RTA_VIA to specify
AF_INET or AF_INET6 gateway.
The common fib_nexthop_info dump function compares the gateway address
family to the nh_common family to know if the gateway should be encoded
as RTA_VIA or RTA_GATEWAY.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Until support is added to the offload drivers, they need to be able to
reject routes with an IPv6 gateway. To that end add a flag to fib_info
that indicates if any fib_nh has a v6 gateway. The flag allows the drivers
to efficiently know the use of a v6 gateway without walking all fib_nh
tied to a fib_info each time a route is added.
Update mlxsw and rocker to reject the routes with extack message as to why.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update ipv4_confirm_neigh to handle an ipv6 gateway.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A common theme in the output path is looking up a neigh entry for a
nexthop, either the gateway in an rtable or a fallback to the daddr
in the skb:
nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
if (unlikely(!neigh))
neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
To allow the nexthop to be an IPv6 address we need to consider the
family of the nexthop and then call __ipv{4,6}_neigh_lookup_noref based
on it.
To make this simpler, add a ip_neigh_gw4 helper similar to ip_neigh_gw6
added in an earlier patch which handles:
neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
if (unlikely(!neigh))
neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
And then add a second one, ip_neigh_for_gw, that calls either
ip_neigh_gw4 or ip_neigh_gw6 based on the address family of the gateway.
Update the output paths in the VRF driver and core v4 code to use
ip_neigh_for_gw simplifying the family based lookup and making both
ready for a v6 nexthop.
ipv4_neigh_lookup has a different need - the potential to resolve a
passed in address in addition to any gateway in the rtable or skb. Since
this is a one-off, add ip_neigh_gw4 and ip_neigh_gw6 diectly. The
difference between __neigh_create used by the helpers and neigh_create
called by ipv4_neigh_lookup is taking a refcount, so add rcu_read_lock_bh
and bump the refcnt on the neigh entry.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A later patch allows an IPv6 gateway with an IPv4 route. The neighbor
entry will exist in the v6 ndisc table and the cached header will contain
the ipv6 protocol which is wrong for an IPv4 packet. For an IPv4 packet to
use the v6 neighbor entry, neigh_output needs to skip the cached header
and just use the output callback for the neigh entry.
A future patchset can look at expanding the hh_cache to handle 2
protocols. For now, IPv6 gateways with an IPv4 route will take the
extra overhead of generating the header.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add helper to use fib6_nh_init to validate a nexthop spec with an IPv6
gateway.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fib_check_nh is currently huge covering multiple uses cases - device only,
device + gateway, and device + gateway with ONLINK. The next patch adds
validation checks for IPv6 which only further complicates it. So, break
fib_check_nh into 2 helpers - one for gateway validation and one for device
only.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for an IPv6 gateway to fib_config. Since a gateway is either
IPv4 or IPv6, make it a union with fc_gw4 where fc_gw_family decides
which address is in use. Update current checks on family and gw4 to
handle ipv6 as well.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for an IPv6 gateway to rtable. Since a gateway is either
IPv4 or IPv6, make it a union with rt_gw4 where rt_gw_family decides
which address is in use.
When dumping the route data, encode an ipv6 nexthop using RTA_VIA.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to rtable, fib_config needs to allow the gateway to be either an
IPv4 or an IPv6 address. To that end, rename fc_gw to fc_gw4 to mean an
IPv4 address and add fc_gw_family. Checks on 'is a gateway set' are changed
to see if fc_gw_family is set. In the process prepare the code for a
fc_gw_family == AF_INET6.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To allow the gateway to be either an IPv4 or IPv6 address, remove
rt_uses_gateway from rtable and replace with rt_gw_family. If
rt_gw_family is set it implies rt_uses_gateway. Rename rt_gateway
to rt_gw4 to represent the IPv4 version.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow the gateway in a fib_nh_common to be from a different address
family than the outer fib{6}_nh. To that end, replace nhc_has_gw with
nhc_gw_family and update users of nhc_has_gw to check nhc_gw_family.
Now nhc_family is used to know if the nh_common is part of a fib_nh
or fib6_nh (used for container_of to get to route family specific data),
and nhc_gw_family represents the address family for the gateway.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
very little code, so it really doesn't make sense to have extra
modules or even a kconfig knob for this.
Merge them and make functionality available unconditionally.
The merge makes inet family route support trivial, so add it
as well here.
Before:
text data bss dec hex filename
835 832 0 1667 683 nft_chain_route_ipv4.ko
870 832 0 1702 6a6 nft_chain_route_ipv6.ko
111568 2556 529 114653 1bfdd nf_tables.ko
After:
text data bss dec hex filename
113133 2556 529 116218 1c5fa nf_tables.ko
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
After commit a297569fe0 ("net/udp: do not touch skb->peeked unless
really needed") the 'peeked' argument of __skb_try_recv_datagram()
and friends is always equal to !!'flags & MSG_PEEK'.
Since such argument is really a boolean info, and the callers have
already 'flags & MSG_PEEK' handy, we can remove it and clean-up the
code a bit.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This structure is now only 4 bytes, so its more efficient
to cache a copy rather than its address.
No significant size difference in allmodconfig vmlinux.
With non-modular kernel that has all XFRM options enabled, this
series reduces vmlinux image size by ~11kb. All xfrm_mode
indirections are gone and all modes are built-in.
before (ipsec-next master):
text data bss dec filename
21071494 7233140 11104324 39408958 vmlinux.master
after this series:
21066448 7226772 11104324 39397544 vmlinux.patched
With allmodconfig kernel, the size increase is only 362 bytes,
even all the xfrm config options removed in this series are
modular.
before:
text data bss dec filename
15731286 6936912 4046908 26715106 vmlinux.master
after this series:
15731492 6937068 4046908 26715468 vmlinux
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
after previous changes, xfrm_mode contains no function pointers anymore
and all modules defining such struct contain no code except an init/exit
functions to register the xfrm_mode struct with the xfrm core.
Just place the xfrm modes core and remove the modules,
the run-time xfrm_mode register/unregister functionality is removed.
Before:
text data bss dec filename
7523 200 2364 10087 net/xfrm/xfrm_input.o
40003 628 440 41071 net/xfrm/xfrm_state.o
15730338 6937080 4046908 26714326 vmlinux
7389 200 2364 9953 net/xfrm/xfrm_input.o
40574 656 440 41670 net/xfrm/xfrm_state.o
15730084 6937068 4046908 26714060 vmlinux
The xfrm*_mode_{transport,tunnel,beet} modules are gone.
v2: replace CONFIG_INET6_XFRM_MODE_* IS_ENABLED guards with CONFIG_IPV6
ones rather than removing them.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Adds an EXPORT_SYMBOL for afinfo_get_rcu, as it will now be called from
ipv6 in case of CONFIG_IPV6=m.
This change has virtually no effect on vmlinux size, but it reduces
afinfo size and allows followup patch to make xfrm modes const.
v2: mark if (afinfo) tests as likely (Sabrina)
re-fetch afinfo according to inner_mode in xfrm_prepare_input().
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
similar to previous patch: no external module dependencies,
so we can avoid the indirection by placing this in the core.
This change removes the last indirection from xfrm_mode and the
xfrm4|6_mode_{beet,tunnel}.c modules contain (almost) no code anymore.
Before:
text data bss dec hex filename
3957 136 0 4093 ffd net/xfrm/xfrm_output.o
587 44 0 631 277 net/ipv4/xfrm4_mode_beet.o
649 32 0 681 2a9 net/ipv4/xfrm4_mode_tunnel.o
625 44 0 669 29d net/ipv6/xfrm6_mode_beet.o
599 32 0 631 277 net/ipv6/xfrm6_mode_tunnel.o
After:
text data bss dec hex filename
5359 184 0 5543 15a7 net/xfrm/xfrm_output.o
171 24 0 195 c3 net/ipv4/xfrm4_mode_beet.o
171 24 0 195 c3 net/ipv4/xfrm4_mode_tunnel.o
172 24 0 196 c4 net/ipv6/xfrm6_mode_beet.o
172 24 0 196 c4 net/ipv6/xfrm6_mode_tunnel.o
v2: fold the *encap_add functions into xfrm*_prepare_output
preserve (move) output2 comment (Sabrina)
use x->outer_mode->encap, not inner
fix a build breakage on ppc (kbuild robot)
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
No external dependencies on any module, place this in the core.
Increase is about 1800 byte for xfrm_input.o.
The beet helpers get added to internal header, as they can be reused
from xfrm_output.c in the next patch (kernel contains several
copies of them in the xfrm{4,6}_mode_beet.c files).
Before:
text data bss dec filename
5578 176 2364 8118 net/xfrm/xfrm_input.o
1180 64 0 1244 net/ipv4/xfrm4_mode_beet.o
171 40 0 211 net/ipv4/xfrm4_mode_transport.o
1163 40 0 1203 net/ipv4/xfrm4_mode_tunnel.o
1083 52 0 1135 net/ipv6/xfrm6_mode_beet.o
172 40 0 212 net/ipv6/xfrm6_mode_ro.o
172 40 0 212 net/ipv6/xfrm6_mode_transport.o
1056 40 0 1096 net/ipv6/xfrm6_mode_tunnel.o
After:
text data bss dec filename
7373 200 2364 9937 net/xfrm/xfrm_input.o
587 44 0 631 net/ipv4/xfrm4_mode_beet.o
171 32 0 203 net/ipv4/xfrm4_mode_transport.o
649 32 0 681 net/ipv4/xfrm4_mode_tunnel.o
625 44 0 669 net/ipv6/xfrm6_mode_beet.o
172 32 0 204 net/ipv6/xfrm6_mode_ro.o
172 32 0 204 net/ipv6/xfrm6_mode_transport.o
599 32 0 631 net/ipv6/xfrm6_mode_tunnel.o
v2: pass inner_mode to xfrm_inner_mode_encap_remove to fix
AF_UNSPEC selector breakage (bisected by Benedict Wong)
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
There are only two versions (tunnel and transport). The ip/ipv6 versions
are only differ in sizeof(iphdr) vs ipv6hdr.
Place this in the core and use x->outer_mode->encap type to call the
correct adjustment helper.
Before:
text data bss dec filename
15730311 6937008 4046908 26714227 vmlinux
After:
15730428 6937008 4046908 26714344 vmlinux
(about 117 byte increase)
v2: use family from x->outer_mode, not inner
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Same is input indirection. Only exception: we need to export
xfrm_outer_mode_output for pktgen.
Increases size of vmlinux by about 163 byte:
Before:
text data bss dec filename
15730208 6936948 4046908 26714064 vmlinux
After:
15730311 6937008 4046908 26714227 vmlinux
xfrm_inner_extract_output has no more external callers, make it static.
v2: add IS_ENABLED(IPV6) guard in xfrm6_prepare_output
add two missing breaks in xfrm_outer_mode_output (Sabrina Dubroca)
add WARN_ON_ONCE for 'call AF_INET6 related output function, but
CONFIG_IPV6=n' case.
make xfrm_inner_extract_output static
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
No need for any indirection or abstraction here, both functions
are pretty much the same and quite small, they also have no external
dependencies.
xfrm_prepare_input can then be made static.
With allmodconfig build, size increase of vmlinux is 25 byte:
Before:
text data bss dec filename
15730207 6936924 4046908 26714039 vmlinux
After:
15730208 6936948 4046908 26714064 vmlinux
v2: Fix INET_XFRM_MODE_TRANSPORT name in is-enabled test (Sabrina Dubroca)
change copied comment to refer to transport and network header,
not skb->{h,nh}, which don't exist anymore. (Sabrina)
make xfrm_prepare_input static (Eyal Birger)
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Now that we have the family available directly in the
xfrm_mode struct, we can use that and avoid one extra dereference.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This will be useful to know if we're supposed to decode ipv4 or ipv6.
While at it, make the unregister function return void, all module_exit
functions did just BUG(); there is never a point in doing error checks
if there is no way to handle such error.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This patch changes rhashtables to use a bit_spin_lock on BIT(1) of the
bucket pointer to lock the hash chain for that bucket.
The benefits of a bit spin_lock are:
- no need to allocate a separate array of locks.
- no need to have a configuration option to guide the
choice of the size of this array
- locking cost is often a single test-and-set in a cache line
that will have to be loaded anyway. When inserting at, or removing
from, the head of the chain, the unlock is free - writing the new
address in the bucket head implicitly clears the lock bit.
For __rhashtable_insert_fast() we ensure this always happens
when adding a new key.
- even when lockings costs 2 updates (lock and unlock), they are
in a cacheline that needs to be read anyway.
The cost of using a bit spin_lock is a little bit of code complexity,
which I think is quite manageable.
Bit spin_locks are sometimes inappropriate because they are not fair -
if multiple CPUs repeatedly contend of the same lock, one CPU can
easily be starved. This is not a credible situation with rhashtable.
Multiple CPUs may want to repeatedly add or remove objects, but they
will typically do so at different buckets, so they will attempt to
acquire different locks.
As we have more bit-locks than we previously had spinlocks (by at
least a factor of two) we can expect slightly less contention to
go with the slightly better cache behavior and reduced memory
consumption.
To enhance type checking, a new struct is introduced to represent the
pointer plus lock-bit
that is stored in the bucket-table. This is "struct rhash_lock_head"
and is empty. A pointer to this needs to be cast to either an
unsigned lock, or a "struct rhash_head *" to be useful.
Variables of this type are most often called "bkt".
Previously "pprev" would sometimes point to a bucket, and sometimes a
->next pointer in an rhash_head. As these are now different types,
pprev is NULL when it would have pointed to the bucket. In that case,
'blk' is used, together with correct locking protocol.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The non-null check on tskb is always false because it is in an else
path of a check on tskb and hence tskb is null in this code block.
This is check is therefore redundant and can be removed as well
as the label coalesc.
if (tsbk) {
...
} else {
...
if (unlikely(!skb)) {
if (tskb) /* can never be true, redundant code */
goto coalesc;
return;
}
}
Addresses-Coverity: ("Logically dead code")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor comment merge conflict in mlx5.
Staging driver has a fixup due to the skb->xmit_more changes
in 'net-next', but was removed in 'net'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux currently disable ECN for incoming connections when the SYN
requests ECN and the IP header has ECT(0)/ECT(1) set, as some
networks were reportedly mangling the ToS byte, hence could later
trigger false congestion notifications.
RFC8311 §4.3 relaxes RFC3168's requirements such that ECT can be set
one TCP control packets (including SYNs). The main benefit of this
is the decreased probability of losing a SYN in a congested
ECN-capable network (i.e., it avoids the initial 1s timeout).
Additionally, this allows the development of newer TCP extensions,
such as AccECN.
This patch relaxes the previous check, by enabling ECN on incoming
connections using SYN+ECT if at least one bit of the reserved flags
of the TCP header is set. Such bit would indicate that the sender of
the SYN is using a newer TCP feature than what the host implements,
such as AccECN, and is thus implementing RFC8311. This enables
end-hosts not supporting such extensions to still negociate ECN, and
to have some of the benefits of using ECN on control packets.
Signed-off-by: Olivier Tilmans <olivier.tilmans@nokia-bell-labs.com>
Suggested-by: Bob Briscoe <research@bobbriscoe.net>
Cc: Koen De Schepper <koen.de_schepper@nokia-bell-labs.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC8257 §3.5 explicitly states that "A DCTCP sender MUST react to
loss episodes in the same way as conventional TCP".
Currently, Linux DCTCP performs no cwnd reduction when losses
are encountered. Optionally, the dctcp_clamp_alpha_on_loss resets
alpha to its maximal value if a RTO happens. This behavior
is sub-optimal for at least two reasons: i) it ignores losses
triggering fast retransmissions; and ii) it causes unnecessary large
cwnd reduction in the future if the loss was isolated as it resets
the historical term of DCTCP's alpha EWMA to its maximal value (i.e.,
denoting a total congestion). The second reason has an especially
noticeable effect when using DCTCP in high BDP environments, where
alpha normally stays at low values.
This patch replace the clamping of alpha by setting ssthresh to
half of cwnd for both fast retransmissions and RTOs, at most once
per RTT. Consequently, the dctcp_clamp_alpha_on_loss module parameter
has been removed.
The table below shows experimental results where we measured the
drop probability of a PIE AQM (not applying ECN marks) at a
bottleneck in the presence of a single TCP flow with either the
alpha-clamping option enabled or the cwnd halving proposed by this
patch. Results using reno or cubic are given for comparison.
| Link | RTT | Drop
TCP CC | speed | base+AQM | probability
==================|=========|==========|============
CUBIC | 40Mbps | 7+20ms | 0.21%
RENO | | | 0.19%
DCTCP-CLAMP-ALPHA | | | 25.80%
DCTCP-HALVE-CWND | | | 0.22%
------------------|---------|----------|------------
CUBIC | 100Mbps | 7+20ms | 0.03%
RENO | | | 0.02%
DCTCP-CLAMP-ALPHA | | | 23.30%
DCTCP-HALVE-CWND | | | 0.04%
------------------|---------|----------|------------
CUBIC | 800Mbps | 1+1ms | 0.04%
RENO | | | 0.05%
DCTCP-CLAMP-ALPHA | | | 18.70%
DCTCP-HALVE-CWND | | | 0.06%
We see that, without halving its cwnd for all source of losses,
DCTCP drives the AQM to large drop probabilities in order to keep
the queue length under control (i.e., it repeatedly faces RTOs).
Instead, if DCTCP reacts to all source of losses, it can then be
controlled by the AQM using similar drop levels than cubic or reno.
Signed-off-by: Koen De Schepper <koen.de_schepper@nokia-bell-labs.com>
Signed-off-by: Olivier Tilmans <olivier.tilmans@nokia-bell-labs.com>
Cc: Bob Briscoe <research@bobbriscoe.net>
Cc: Lawrence Brakmo <brakmo@fb.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Daniel Borkmann <borkmann@iogearbox.net>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Andrew Shewmaker <agshew@gmail.com>
Cc: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Florian Westphal <fw@strlen.de>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Export fib_nexthop_info and fib_add_nexthop for use by IPv6 code.
Remove rt6_nexthop_info and rt6_add_nexthop in favor of the IPv4
versions. Update fib_nexthop_info for IPv6 linkdown check and
RTA_GATEWAY for AF_INET6.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the exception of the nexthop weight, the nexthop attributes used by
fib_nexthop_info and fib_add_nexthop come from the fib_nh_common struct.
Update both to use it and change fib_nexthop_info to check the family
as needed.
nexthop weight comes from the common struct for existing use cases, but
for nexthop groups the weight is outside of the fib_nh_common to allow
the same nexthop definition to be used in multiple groups with different
weights.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to ipv6, move addition of nexthop attributes to dump
message into helpers that are called for both single path and
multipath routes. Align the new helpers to the IPv6 variant
which most notably means computing the flags argument based on
settings in nh_flags.
The RTA_FLOW argument is unique to IPv4, so it is appended after
the new fib_nexthop_info helper. The intent of a later patch is to
make both fib_nexthop_info and fib_add_nexthop usable for both IPv4
and IPv6. This patch is stepping stone in that direction.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Most of the ipv4 code only needs data from fib_nh_common. Add
fib_nh_common selection to fib_result and update users to use it.
Right now, fib_nh_common in fib_result will point to a fib_nh struct
that is embedded within a fib_info:
fib_info --> fib_nh
fib_nh
...
fib_nh
^
fib_result->nhc ----+
Later, nhc can point to a fib_nh within a nexthop struct:
fib_info --> nexthop --> fib_nh
^
fib_result->nhc ---------------+
or for a nexthop group:
fib_info --> nexthop --> nexthop --> fib_nh
nexthop --> fib_nh
...
nexthop --> fib_nh
^
fib_result->nhc ---------------------------+
In all cases nhsel within fib_result will point to which leg in the
multipath route is used.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update fib_table_lookup tracepoint to take a fib_nh_common struct and
dump the v6 gateway address if the nexthop uses it.
Over the years saddr has not proven useful and the output of the
tracepoint produces very long lines. Since saddr is not part of
fib_nh_common, drop it. If it needs to be added later, fib_nh which
contains saddr can be obtained from a fib_nh_common via container_of.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently don't reload pointers pointing into skb header
after doing pskb_may_pull() in _decode_session4(). So in case
pskb_may_pull() changed the pointers, we read from random
memory. Fix this by putting all the needed infos on the
stack, so that we don't need to access the header pointers
after doing pskb_may_pull().
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
