linux/net
Mat Martineau d12cd0bf5d mptcp: Do TCP fallback on early DSS checksum failure
commit ae66fb2ba6 upstream.

RFC 8684 section 3.7 describes several opportunities for a MPTCP
connection to "fall back" to regular TCP early in the connection
process, before it has been confirmed that MPTCP options can be
successfully propagated on all SYN, SYN/ACK, and data packets. If a peer
acknowledges the first received data packet with a regular TCP header
(no MPTCP options), fallback is allowed.

If the recipient of that first data packet finds a MPTCP DSS checksum
error, this provides an opportunity to fail gracefully with a TCP
fallback rather than resetting the connection (as might happen if a
checksum failure were detected later).

This commit modifies the checksum failure code to attempt fallback on
the initial subflow of a MPTCP connection, only if it's a failure in the
first data mapping. In cases where the peer initiates the connection,
requests checksums, is the first to send data, and the peer is sending
incorrect checksums (see
https://github.com/multipath-tcp/mptcp_net-next/issues/275), this allows
the connection to proceed as TCP rather than reset.

Fixes: dd8bcd1768 ("mptcp: validate the data checksum")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[mathew.j.martineau: backport: Resolved bitfield conflict in protocol.h]
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2022-05-25 14:42:07 +02:00
..
6lowpan 6lowpan: iphc: Fix an off-by-one check of array index 2021-07-22 16:19:03 +02:00
9p xen/9p: use alloc/free_pages_exact() 2022-03-11 12:22:36 +01:00
802 net: 802: remove dead leftover after ipx driver removal 2021-08-13 16:30:35 -07:00
8021q net: vlan: fix underflow for the real_dev refcnt 2021-12-01 09:04:53 +01:00
appletalk net: socket: rework compat_ifreq_ioctl() 2021-07-23 14:20:25 +01:00
atm atm: Use list_for_each_entry() to simplify code in resources.c 2021-06-10 14:08:09 -07:00
ax25 ax25: Fix UAF bugs in ax25 timers 2022-04-20 09:34:22 +02:00
batman-adv batman-adv: Don't skb_split skbuffs with frag_list 2022-05-18 10:26:47 +02:00
bluetooth Bluetooth: Fix the creation of hdev->name 2022-05-15 20:18:52 +02:00
bpf bpf: Make remote_port field in struct bpf_sk_lookup 16-bit wide 2022-04-13 20:59:25 +02:00
bpfilter bpfilter: Specify the log level for the kmsg message 2021-06-25 13:13:50 +02:00
bridge net: bridge: Clear offload_fwd_mark when passing frame up bridge interface. 2022-05-25 09:57:34 +02:00
caif net-caif: avoid user-triggerable WARN_ON(1) 2021-09-14 12:51:15 +01:00
can can: isotp: remove re-binding of bound socket 2022-05-12 12:30:09 +02:00
ceph libceph: fix potential use-after-free on linger ping and resends 2022-05-25 09:57:28 +02:00
core net: fix wrong network header length 2022-05-25 09:57:35 +02:00
dcb net: dcb: disable softirqs in dcbnl_flush_dev() 2022-03-08 19:12:52 +01:00
dccp tcp: switch orphan_count to bare per-cpu counters 2021-11-18 19:16:33 +01:00
decnet net: Remove redundant if statements 2021-08-05 13:27:50 +01:00
dns_resolver net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
dsa net: dsa: Add missing of_node_put() in dsa_port_link_register_of 2022-05-09 09:14:34 +02:00
ethernet move netdev_boot_setup into Space.c 2021-08-03 13:05:26 +01:00
ethtool ethtool: do not perform operations on net devices being unregistered 2021-12-14 10:57:09 +01:00
hsr net: hsr: don't check sequence number if tag removal is offloaded 2021-06-16 12:13:01 -07:00
ieee802154 net: ieee802154: Return meaningful error codes from the netlink helpers 2022-02-08 18:34:09 +01:00
ife net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
ipv4 xfrm: fix "disable_policy" flag use when arriving from different devices 2022-05-25 09:57:30 +02:00
ipv6 secure_seq: use the 64 bits of the siphash for port offset calculation 2022-05-18 10:26:53 +02:00
iucv net/iucv: Replace deprecated CPU-hotplug functions. 2021-08-09 10:13:32 +01:00
kcm net: sock: introduce sk_error_report 2021-06-29 11:28:21 -07:00
key net: af_key: add check for pfkey_broadcast in function pfkey_process 2022-05-25 09:57:32 +02:00
l2tp net/l2tp: Fix reference count leak in l2tp_udp_recv_core 2021-09-09 11:00:20 +01:00
l3mdev l3mdev: l3mdev_master_upper_ifindex_by_index_rcu should be using netdev_master_upper_dev_get_rcu 2022-04-27 14:38:53 +02:00
lapb net: lapb: Use list_for_each_entry() to simplify code in lapb_iface.c 2021-06-08 16:31:25 -07:00
llc llc: only change llc->dev when bind() succeeds 2022-03-28 09:58:46 +02:00
mac80211 mac80211: fix rx reordering with non explicit / psmp ack policy 2022-05-25 09:57:35 +02:00
mac802154 ieee802154: Remove redundant initialization of variable ret 2021-09-07 14:06:08 +01:00
mctp mctp: Fix check for dev_hard_header() result 2022-04-13 20:59:16 +02:00
mpls net: mpls: Fix notifications when deleting a device 2021-12-08 09:04:47 +01:00
mptcp mptcp: Do TCP fallback on early DSS checksum failure 2022-05-25 14:42:07 +02:00
ncsi net/ncsi: check for error return from call to nla_put_u32 2022-01-05 12:42:37 +01:00
netfilter netfilter: flowtable: move dst_check to packet path 2022-05-25 09:57:33 +02:00
netlabel netlabel: fix out-of-bounds memory accesses 2022-04-13 20:59:10 +02:00
netlink netlink: do not reset transport header in netlink_recvmsg() 2022-05-18 10:26:49 +02:00
netrom netrom: fix api breakage in nr_setsockopt() 2022-01-27 11:04:00 +01:00
nfc NFC: nci: fix sleep in atomic context bugs caused by nci_skb_alloc 2022-05-25 09:57:32 +02:00
nsh treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
openvswitch netfilter: conntrack: convert to refcount_t api 2022-04-27 14:39:01 +02:00
packet net/packet: fix packet_sock xmit return value checking 2022-04-27 14:38:53 +02:00
phonet phonet: refcount leak in pep_sock_accep 2022-01-11 15:35:16 +01:00
psample psample: Add additional metadata attributes 2021-03-14 15:00:43 -07:00
qrtr net: qrtr: revert check in qrtr_endpoint_post() 2021-09-02 11:37:02 +01:00
rds rds: memory leak in __rds_conn_create() 2021-12-22 09:32:42 +01:00
rfkill rfkill: make new event layout opt-in 2022-04-08 14:23:00 +02:00
rose net: rose: Fix fall-through warnings for Clang 2021-03-10 12:45:15 -08:00
rxrpc rxrpc: Enable IPv6 checksums on transport socket 2022-05-12 12:30:19 +02:00
sched net/sched: act_pedit: sanitize shift argument before usage 2022-05-25 09:57:30 +02:00
sctp sctp: check asoc strreset_chunk in sctp_generate_reconf_event 2022-05-09 09:14:35 +02:00
smc net/smc: non blocking recvmsg() return -EAGAIN when no data and signal_pending 2022-05-18 10:26:51 +02:00
strparser bpf: sockmap, strparser, and tls are reusing qdisc_skb_cb and colliding 2021-11-18 19:17:11 +01:00
sunrpc SUNRPC: Ensure we flush any closed sockets before xs_xprt_free() 2022-05-18 10:26:57 +02:00
switchdev net: make switchdev_bridge_port_{,unoffload} loosely coupled with the bridge 2021-08-04 12:35:07 +01:00
tipc tipc: fix the timer expires after interval 100ms 2022-04-08 14:23:43 +02:00
tls tls: Fix context leak on tls_device_down 2022-05-18 10:26:51 +02:00
unix af_unix: Support POLLPRI for OOB. 2022-04-08 14:24:14 +02:00
vmw_vsock vsock/virtio: enable VQs early on probe 2022-04-08 14:23:51 +02:00
wireless nl80211: fix locking in nl80211_set_tx_bitrate_mask() 2022-05-25 09:57:35 +02:00
x25 net/x25: Fix null-ptr-deref caused by x25_disconnect 2022-04-08 14:23:53 +02:00
xdp xsk: Fix l2fwd for copy mode + busy poll combo 2022-05-09 09:14:32 +02:00
xfrm xfrm: rework default policy structure 2022-05-25 09:57:30 +02:00
compat.c net: Return the correct errno code 2021-06-03 15:13:56 -07:00
devres.c net: devres: Correct a grammatical error 2021-06-11 12:55:28 -07:00
Kconfig mctp: Add MCTP base 2021-07-29 15:06:49 +01:00
Makefile mctp: Add MCTP base 2021-07-29 15:06:49 +01:00
socket.c net: fix SOF_TIMESTAMPING_BIND_PHC to work with multiple sockets 2022-01-27 11:03:52 +01:00
sysctl_net.c net: Ensure net namespace isolation of sysctls 2021-04-12 13:27:11 -07:00