linux/net/ipv6
Rocco Yue 49b99da2c9 ipv6: add IFLA_INET6_RA_MTU to expose mtu value
The kernel provides a "/proc/sys/net/ipv6/conf/<iface>/mtu"
file, which can temporarily record the mtu value of the last
received RA message when the RA mtu value is lower than the
interface mtu, but this proc has following limitations:

(1) when the interface mtu (/sys/class/net/<iface>/mtu) is
updeated, mtu6 (/proc/sys/net/ipv6/conf/<iface>/mtu) will
be updated to the value of interface mtu;
(2) mtu6 (/proc/sys/net/ipv6/conf/<iface>/mtu) only affect
ipv6 connection, and not affect ipv4.

Therefore, when the mtu option is carried in the RA message,
there will be a problem that the user sometimes cannot obtain
RA mtu value correctly by reading mtu6.

After this patch set, if a RA message carries the mtu option,
you can send a netlink msg which nlmsg_type is RTM_GETLINK,
and then by parsing the attribute of IFLA_INET6_RA_MTU to
get the mtu value carried in the RA message received on the
inet6 device. In addition, you can also get a link notification
when ra_mtu is updated so it doesn't have to poll.

In this way, if the MTU values that the device receives from
the network in the PCO IPv4 and the RA IPv6 procedures are
different, the user can obtain the correct ipv6 ra_mtu value
and compare the value of ra_mtu and ipv4 mtu, then the device
can use the lower MTU value for both IPv4 and IPv6.

Signed-off-by: Rocco Yue <rocco.yue@mediatek.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20210827150412.9267-1-rocco.yue@mediatek.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-27 17:29:18 -07:00
..
ila net: Add MODULE_DESCRIPTION entries to network modules 2020-06-20 21:33:57 -07:00
netfilter netfilter: x_tables: never register tables by default 2021-08-09 10:22:01 +02:00
addrconf_core.c ipv6: add ipv6_dev_find to stubs 2021-03-30 13:29:39 -07:00
addrconf.c ipv6: add IFLA_INET6_RA_MTU to expose mtu value 2021-08-27 17:29:18 -07:00
addrlabel.c ipv6: addrlabel: fix possible memory leak in ip6addrlbl_net_init 2020-11-25 11:20:16 -08:00
af_inet6.c ipv6: ioam: Data plane support for Pre-allocated Trace 2021-07-21 08:14:33 -07:00
ah6.c xfrm: remove hdr_offset indirection 2021-06-11 14:48:50 +02:00
anycast.c ipv6: fix memory leaks on IPV6_ADDRFORM path 2020-07-30 16:30:55 -07:00
calipso.c cipso,calipso: resolve a number of problems with the DOI refcounts 2021-03-04 15:26:57 -08:00
datagram.c lsm,selinux: pass flowi_common instead of flowi to the LSM hooks 2020-11-23 18:36:21 -05:00
esp6_offload.c xfrm: remove description from xfrm_type struct 2021-06-09 09:38:52 +02:00
esp6.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-06-29 15:45:27 -07:00
exthdrs_core.c ipv6: remove printk 2019-07-27 14:23:48 -07:00
exthdrs_offload.c
exthdrs.c ipv6: exthdrs: get rid of indirect calls in ip6_parse_tlv() 2021-08-04 10:34:40 +01:00
fib6_notifier.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
fib6_rules.c ipv6: fib6: remove redundant initialization of variable err 2021-06-14 12:42:26 -07:00
fou6.c net: Add MODULE_DESCRIPTION entries to network modules 2020-06-20 21:33:57 -07:00
icmp.c ipv6: ICMPV6: add response to ICMPV6 RFC 8335 PROBE messages 2021-06-28 14:29:45 -07:00
inet6_connection_sock.c lsm,selinux: pass flowi_common instead of flowi to the LSM hooks 2020-11-23 18:36:21 -05:00
inet6_hashtables.c net: ipv6: remove unused arg exact_dif in compute_score 2020-08-31 13:08:10 -07:00
ioam6_iptunnel.c ipv6: ioam: Support for IOAM injection with lwtunnels 2021-07-21 08:14:33 -07:00
ioam6.c ipv6: ioam: Support for IOAM injection with lwtunnels 2021-07-21 08:14:33 -07:00
ip6_checksum.c
ip6_fib.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-26 17:57:57 -07:00
ip6_flowlabel.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
ip6_gre.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-26 17:57:57 -07:00
ip6_icmp.c net: icmp: pass zeroed opts from icmp{,v6}_ndo_send before sending 2021-02-23 11:29:52 -08:00
ip6_input.c ipv6: weaken the v4mapped source check 2021-03-18 11:19:23 -07:00
ip6_offload.c net/core: move gro function declarations to separate header 2021-02-04 18:37:57 -08:00
ip6_offload.h
ip6_output.c ipv6: use skb_expand_head in ip6_xmit 2021-08-03 11:21:39 +01:00
ip6_tunnel.c ip_tunnel: use ndo_siocdevprivate 2021-07-27 20:11:44 +01:00
ip6_udp_tunnel.c net: Make locking in sock_bindtoindex optional 2020-06-01 14:57:14 -07:00
ip6_vti.c ip_tunnel: use ndo_siocdevprivate 2021-07-27 20:11:44 +01:00
ip6mr.c net: Remove redundant if statements 2021-08-05 13:27:50 +01:00
ipcomp6.c xfrm: remove hdr_offset indirection 2021-06-11 14:48:50 +02:00
ipv6_sockglue.c net/ipv4/ipv6: Replace one-element arraya with flexible-array members 2021-08-05 11:46:42 +01:00
Kconfig ipv6: ioam: Support for IOAM injection with lwtunnels 2021-07-21 08:14:33 -07:00
Makefile ipv6: ioam: Support for IOAM injection with lwtunnels 2021-07-21 08:14:33 -07:00
mcast_snoop.c net: bridge: mcast: fix broken length + header check for MRDv6 Adv. 2021-04-27 14:02:06 -07:00
mcast.c net/ipv6/mcast: Use struct_size() helper 2021-08-05 11:46:42 +01:00
mip6.c xfrm: ipv6: move mip6_rthdr_offset into xfrm core 2021-06-11 14:48:50 +02:00
ndisc.c ipv6: add IFLA_INET6_RA_MTU to expose mtu value 2021-08-27 17:29:18 -07:00
netfilter.c netfilter: Dissect flow after packet mangling 2021-04-18 22:04:16 +02:00
output_core.c ipv6: use prandom_u32() for ID generation 2021-05-31 22:12:08 -07:00
ping.c lsm,selinux: pass flowi_common instead of flowi to the LSM hooks 2020-11-23 18:36:21 -05:00
proc.c net: udp: introduce UDP_MIB_MEMERRORS for udp_mem 2020-11-09 15:34:44 -08:00
protocol.c
raw.c net: sock: introduce sk_error_report 2021-06-29 11:28:21 -07:00
reassembly.c ipv6: record frag_max_size in atomic fragments in input path 2021-05-21 15:02:25 -07:00
route.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-26 17:57:57 -07:00
rpl_iptunnel.c net: ipv6: rpl_iptunnel: simplify the return expression of rpl_do_srh() 2020-12-08 16:22:54 -08:00
rpl.c net: ipv6: rpl*: Fix strange kerneldoc warnings due to bad header 2020-10-30 12:12:52 -07:00
seg6_hmac.c crypto: sha - split sha.h into sha1.h and sha2.h 2020-11-20 14:45:33 +11:00
seg6_iptunnel.c seg6_iptunnel: Refactor seg6_lwt_headroom out of uapi header 2020-08-03 17:57:40 -07:00
seg6_local.c seg6: add support for SRv6 End.DT46 Behavior 2021-06-18 11:35:47 -07:00
seg6.c net: Remove redundant assignment to err 2021-04-29 15:34:15 -07:00
sit.c ip_tunnel: use ndo_siocdevprivate 2021-07-27 20:11:44 +01:00
syncookies.c selinux/stable-5.11 PR 20201214 2020-12-16 11:01:04 -08:00
sysctl_net_ipv6.c ipv6: ioam: Data plane support for Pre-allocated Trace 2021-07-21 08:14:33 -07:00
tcp_ipv6.c net: send SYNACK packet with accepted fwmark 2021-07-09 11:24:02 -07:00
tcpv6_offload.c
tunnel6.c tunnel6: add tunnel6_input_afinfo for ipip and ipv6 tunnels 2020-07-09 12:52:37 +02:00
udp_impl.h net: pass a sockptr_t into ->setsockopt 2020-07-24 15:41:54 -07:00
udp_offload.c udp: properly complete L4 GRO over UDP tunnel packet 2021-03-30 17:06:49 -07:00
udp.c udp: check encap socket in __udp_lib_err 2021-07-21 08:49:31 -07:00
udplite.c net/ipv6: remove compat_ipv6_{get,set}sockopt 2020-07-19 18:16:41 -07:00
xfrm6_input.c xfrm: state: remove extract_input indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm6_output.c net: ipv6: fix return value of ip6_skb_dst_mtu 2021-07-02 11:57:01 -07:00
xfrm6_policy.c net: add bool confirm_neigh parameter for dst_ops.update_pmtu 2019-12-24 22:28:54 -08:00
xfrm6_protocol.c xfrm: add support for UDPv6 encapsulation of ESP 2020-04-28 11:28:36 +02:00
xfrm6_state.c xfrm: remove output_finish indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm6_tunnel.c xfrm: remove description from xfrm_type struct 2021-06-09 09:38:52 +02:00