linux/include/net
Dimitris Michailidis 90427ef5d2 ipv6: fix flow labels when the traffic class is non-0
ip6_make_flowlabel() determines the flow label for IPv6 packets. It's
supposed to be passed a flow label, which it returns as is if non-0 and
in some other cases, otherwise it calculates a new value.

The problem is callers often pass a flowi6.flowlabel, which may also
contain traffic class bits. If the traffic class is non-0
ip6_make_flowlabel() mistakes the non-0 it gets as a flow label and
returns the whole thing. Thus it can return a 'flow label' longer than
20b and the low 20b of that is typically 0 resulting in packets with 0
label. Moreover, different packets of a flow may be labeled differently.
For a TCP flow with ECN non-payload and payload packets get different
labels as exemplified by this pair of consecutive packets:

(pure ACK)
Internet Protocol Version 6, Src: 2002:af5:11a3::, Dst: 2002:af5:11a2::
    0110 .... = Version: 6
    .... 0000 0000 .... .... .... .... .... = Traffic Class: 0x00 (DSCP: CS0, ECN: Not-ECT)
        .... 0000 00.. .... .... .... .... .... = Differentiated Services Codepoint: Default (0)
        .... .... ..00 .... .... .... .... .... = Explicit Congestion Notification: Not ECN-Capable Transport (0)
    .... .... .... 0001 1100 1110 0100 1001 = Flow Label: 0x1ce49
    Payload Length: 32
    Next Header: TCP (6)

(payload)
Internet Protocol Version 6, Src: 2002:af5:11a3::, Dst: 2002:af5:11a2::
    0110 .... = Version: 6
    .... 0000 0010 .... .... .... .... .... = Traffic Class: 0x02 (DSCP: CS0, ECN: ECT(0))
        .... 0000 00.. .... .... .... .... .... = Differentiated Services Codepoint: Default (0)
        .... .... ..10 .... .... .... .... .... = Explicit Congestion Notification: ECN-Capable Transport codepoint '10' (2)
    .... .... .... 0000 0000 0000 0000 0000 = Flow Label: 0x00000
    Payload Length: 688
    Next Header: TCP (6)

This patch allows ip6_make_flowlabel() to be passed more than just a
flow label and has it extract the part it really wants. This was simpler
than modifying the callers. With this patch packets like the above become

Internet Protocol Version 6, Src: 2002:af5:11a3::, Dst: 2002:af5:11a2::
    0110 .... = Version: 6
    .... 0000 0000 .... .... .... .... .... = Traffic Class: 0x00 (DSCP: CS0, ECN: Not-ECT)
        .... 0000 00.. .... .... .... .... .... = Differentiated Services Codepoint: Default (0)
        .... .... ..00 .... .... .... .... .... = Explicit Congestion Notification: Not ECN-Capable Transport (0)
    .... .... .... 1010 1111 1010 0101 1110 = Flow Label: 0xafa5e
    Payload Length: 32
    Next Header: TCP (6)

Internet Protocol Version 6, Src: 2002:af5:11a3::, Dst: 2002:af5:11a2::
    0110 .... = Version: 6
    .... 0000 0010 .... .... .... .... .... = Traffic Class: 0x02 (DSCP: CS0, ECN: ECT(0))
        .... 0000 00.. .... .... .... .... .... = Differentiated Services Codepoint: Default (0)
        .... .... ..10 .... .... .... .... .... = Explicit Congestion Notification: ECN-Capable Transport codepoint '10' (2)
    .... .... .... 1010 1111 1010 0101 1110 = Flow Label: 0xafa5e
    Payload Length: 688
    Next Header: TCP (6)

Signed-off-by: Dimitris Michailidis <dmichail@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-31 13:16:59 -05:00
..
9p
bluetooth Bluetooth: __ variants of u8 and friends are not neccessary inside kernel 2016-11-27 07:41:05 +01:00
caif
irda
iucv
netfilter netfilter: nf_tables: deconstify walk callback function 2017-01-24 21:46:58 +01:00
netns ipv4: Namespaceify tcp_tw_reuse knob 2016-12-27 12:28:07 -05:00
nfc NFC: digital: Add support for NFC DEP Response Waiting Time 2016-07-11 02:01:14 +02:00
phonet
sctp Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
tc_act net/sched: act_tunnel_key: add helper inlines to access tcf_tunnel_key 2016-11-09 13:41:53 -05:00
6lowpan.h 6lowpan: add 802.15.4 short addr slaac 2016-06-15 20:41:22 -07:00
act_api.h net_sched: gen_estimator: complete rewrite of rate estimators 2016-12-05 15:21:59 -05:00
addrconf.h ipv6: fix a potential deadlock in do_ipv6_setsockopt() 2016-10-21 11:29:02 -04:00
af_ieee802154.h
af_rxrpc.h rxrpc: Rewrite the data and ack handling code 2016-09-08 11:10:12 +01:00
af_unix.h af_unix: split 'u->readlock' into two: 'iolock' and 'bindlock' 2016-09-04 13:29:29 -07:00
af_vsock.h VSOCK: Introduce virtio_vsock_common.ko 2016-08-02 02:57:29 +03:00
ah.h
arp.h
atmclip.h
ax25.h
ax88796.h
bond_3ad.h
bond_alb.h
bond_options.h
bonding.h netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
busy_poll.h udp: enable busy polling for all sockets 2016-11-18 10:44:31 -05:00
calipso.h calipso: Add a label cache. 2016-06-27 15:06:17 -04:00
cfg80211-wext.h
cfg80211.h cfg80211/mac80211: fix BSS leaks when abandoning assoc attempts 2016-12-09 12:57:49 +01:00
cfg802154.h ieee802154: add netns support 2016-07-08 12:20:57 +02:00
checksum.h Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
cipso_ipv4.h
cls_cgroup.h cls_cgroup: get sk_classid only from full sockets 2016-04-19 20:09:25 -04:00
codel_impl.h codel: split into multiple files 2016-04-25 16:44:27 -04:00
codel_qdisc.h net_sched: fq_codel: cache skb->truesize into skb->cb 2016-06-25 12:19:35 -04:00
codel.h codel: split into multiple files 2016-04-25 16:44:27 -04:00
compat.h packet: compat support for sock_fprog 2016-06-09 23:41:03 -07:00
datalink.h
dcbevent.h
dcbnl.h
devlink.h devlink: Add E-Switch inline mode control 2016-11-24 16:01:14 -05:00
dn_dev.h
dn_fib.h
dn_neigh.h
dn_nsp.h
dn_route.h
dn.h
dsa.h net: dsa: add port fast ageing 2016-09-23 08:38:50 -04:00
dsfield.h
dst_cache.h
dst_metadata.h net/dst: Add dst port to dst_metadata utility functions 2016-11-09 13:41:54 -05:00
dst_ops.h
dst.h route: move lwtunnel state to a single place 2016-04-25 16:20:09 -04:00
esp.h
ethoc.h
fib_rules.h net: core: add UID to flows, rules, and routes 2016-11-04 14:45:23 -04:00
firewire.h
flow_dissector.h flow dissector: ICMP support 2016-12-08 11:45:21 -05:00
flow.h Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-12 19:25:04 -08:00
flowcache.h net/flowcache: Convert to hotplug state machine 2016-11-09 23:45:28 +01:00
fou.h fou: Add encap ops for IPv6 tunnels 2016-05-20 18:03:16 -04:00
fq_impl.h fq.h: Port memory limit mechanism from fq_codel 2016-09-30 13:29:21 +02:00
fq.h fq.h: Port memory limit mechanism from fq_codel 2016-09-30 13:29:21 +02:00
garp.h
gen_stats.h net_sched: gen_estimator: complete rewrite of rate estimators 2016-12-05 15:21:59 -05:00
genetlink.h genetlink: Make family a signed integer. 2016-11-13 12:14:59 -05:00
geneve.h net: Remove deprecated tunnel specific UDP offload functions 2016-06-17 20:23:32 -07:00
gre.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-08-18 01:17:32 -04:00
gro_cells.h gro_cells: mark napi struct as not busy poll candidates 2016-11-15 22:27:27 -05:00
gtp.h gtp: #define #define _GTP_H_ and not #define _GTP_H 2016-07-25 17:55:43 -07:00
gue.h
hwbm.h
icmp.h net: snmp: kill STATS_BH macros 2016-04-27 22:48:25 -04:00
ieee80211_radiotap.h wireless: radiotap: fix timestamp sampling position values 2016-10-19 12:11:36 +02:00
ieee802154_netdev.h
if_inet6.h ipv6 addrconf: Implemented enhanced DAD (RFC7527) 2016-12-03 23:21:37 -05:00
ila.h
inet6_connection_sock.h inet: Fix get port to handle zero port number with soreuseport set 2016-12-17 11:13:19 -05:00
inet6_hashtables.h tcp/dccp: do not touch listener sk_refcnt under synflood 2016-04-04 22:11:20 -04:00
inet_common.h ip4ip6: Support for GSO/GRO 2016-05-20 18:03:17 -04:00
inet_connection_sock.h inet: Fix get port to handle zero port number with soreuseport set 2016-12-17 11:13:19 -05:00
inet_ecn.h ipv6: suppress sparse warnings in IP6_ECN_set_ce() 2016-08-13 15:08:00 -07:00
inet_frag.h
inet_hashtables.h tcp/dccp: do not touch listener sk_refcnt under synflood 2016-04-04 22:11:20 -04:00
inet_sock.h ipv4: add IP_RECVFRAGSIZE cmsg 2016-11-03 15:41:11 -04:00
inet_timewait_sock.h
inetpeer.h
ip6_checksum.h
ip6_fib.h net: ipv6: Fix processing of RAs in presence of VRF 2016-10-27 16:30:52 -04:00
ip6_route.h net: inet: Support UID-based routing in IP protocols. 2016-11-04 14:45:23 -04:00
ip6_tunnel.h ip6_tunnel: Clear IP6CB in ip6tunnel_xmit() 2016-11-02 15:18:36 -04:00
ip_fib.h ipv4: fib: Replay events when registering FIB notifier 2016-12-03 19:29:35 -05:00
ip_tunnels.h netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
ip_vs.h ipvs: update real-server binding of outgoing connections in SIP-pe 2016-06-06 09:47:25 +09:00
ip.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-11-15 10:54:36 -05:00
ipcomp.h
ipconfig.h
ipv6.h ipv6: fix flow labels when the traffic class is non-0 2017-01-31 13:16:59 -05:00
ipx.h
iw_handler.h
kcm.h kcm: Use stream parser 2016-08-17 19:36:23 -04:00
l3mdev.h net: ipv4: Do not drop to make_route if oif is l3mdev 2016-10-13 12:05:26 -04:00
lapb.h
lib80211.h
llc_c_ac.h
llc_c_ev.h
llc_c_st.h
llc_conn.h
llc_if.h
llc_pdu.h
llc_s_ac.h
llc_s_ev.h
llc_s_st.h
llc_sap.h
llc.h
lwtunnel.h net: Specify the owning module for lwtunnel ops 2017-01-24 16:21:36 -05:00
mac80211.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-10-30 12:42:58 -04:00
mac802154.h ieee802154: cleanup WARN_ON for fc fetch 2016-07-08 13:23:12 +02:00
mip6.h
mld.h
mpls_iptunnel.h
mpls.h openvswitch: use mpls_hdr 2016-10-03 02:00:22 -04:00
mrp.h
ncsi.h net/ncsi: Introduce ncsi_stop_dev() 2016-10-04 02:11:51 -04:00
ndisc.h ipv6 addrconf: Implemented enhanced DAD (RFC7527) 2016-12-03 23:21:37 -05:00
neighbour.h
net_namespace.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-11-22 13:27:16 -05:00
net_ratelimit.h
netevent.h neigh: Send a notification when DELAY_PROBE_TIME changes 2016-07-05 09:06:29 -07:00
netlabel.h netlabel: Implement CALIPSO config functions for SMACK. 2016-06-27 15:06:18 -04:00
netlink.h netlink: revert broken, broken "2-clause nla_ok()" 2016-12-13 14:54:44 -05:00
netprio_cgroup.h
netrom.h
nexthop.h
nl802154.h ieee802154: add netns support 2016-07-08 12:20:57 +02:00
p8022.h
ping.h net: ping: make ping_v6_sendmsg static 2016-03-23 22:09:58 -04:00
pkt_cls.h net/sched: cls_flower: Add offload support using egress Hardware device 2016-12-02 13:28:37 -05:00
pkt_sched.h net: make default TX queue length a defined constant 2016-11-07 20:15:55 -05:00
pptp.h pptp: Refactor the struct and macros of PPTP codes 2016-08-15 10:55:53 -07:00
protocol.h udp: Remove udp_offloads 2016-04-07 16:53:30 -04:00
psnap.h
raw.h net: ip, diag -- Add diag interface for raw sockets 2016-10-23 19:35:24 -04:00
rawv6.h net: ip, diag -- Add diag interface for raw sockets 2016-10-23 19:35:24 -04:00
red.h ktime: Get rid of the union 2016-12-25 17:21:22 +01:00
regulatory.h
request_sock.h inet: reqsk_alloc() needs to take care of dead listeners 2016-04-04 22:11:19 -04:00
rose.h
route.h net: inet: Support UID-based routing in IP protocols. 2016-11-04 14:45:23 -04:00
rtnetlink.h net: rtnetlink: add support for the IFLA_STATS_LINK_XSTATS_SLAVE attribute 2016-06-30 06:15:04 -04:00
sch_generic.h net_sched: gen_estimator: complete rewrite of rate estimators 2016-12-05 15:21:59 -05:00
scm.h
secure_seq.h tcp: randomize tcp timestamp offsets for each connection 2016-12-02 12:49:59 -05:00
seg6_hmac.h ipv6: sr: add core files for SR HMAC support 2016-11-09 20:40:06 -05:00
seg6.h ipv6: sr: add core files for SR HMAC support 2016-11-09 20:40:06 -05:00
slhc_vj.h
snmp.h net: snmp: fix 64bit stats on 32bit arches 2016-04-28 11:49:45 -04:00
sock_reuseport.h
sock.h ktime: Get rid of the union 2016-12-25 17:21:22 +01:00
Space.h
stp.h
strparser.h kcm: Remove TCP specific references from kcm and strparser 2016-08-28 23:32:41 -04:00
switchdev.h switchdev: remove FIB offload infrastructure 2016-09-28 04:48:00 -04:00
tcp_states.h
tcp.h ipv4: Namespaceify tcp_tw_reuse knob 2016-12-27 12:28:07 -05:00
timewait_sock.h
transp_v6.h ipv6: add new struct ipcm6_cookie 2016-05-03 16:08:14 -04:00
tso.h
udp_tunnel.h vxlan: Add new UDP encapsulation offload type for VXLAN-GPE 2016-06-17 20:23:32 -07:00
udp.h udplite: fix NULL pointer dereference 2016-11-15 11:59:38 -05:00
udplite.h Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-12-16 10:24:44 -08:00
vsock_addr.h
vxlan.h vxlan: remove unsed vxlan_dev_dst_port() 2016-11-15 12:16:13 -05:00
wext.h
wimax.h
x25.h
x25device.h
xfrm.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-09-23 06:46:57 -04:00