Pengcheng Yang aa138efd2b tcp: fix F-RTO may not work correctly when receiving DSACK ... [ Upstream commit d9157f6806d1499e173770df1f1b234763de5c79 ] Currently DSACK is regarded as a dupack, which may cause F-RTO to incorrectly enter "loss was real" when receiving DSACK. Packetdrill to demonstrate: // Enable F-RTO and TLP 0 `sysctl -q net.ipv4.tcp_frto=2` 0 `sysctl -q net.ipv4.tcp_early_retrans=3` 0 `sysctl -q net.ipv4.tcp_congestion_control=cubic` // Establish a connection +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 // RTT 10ms, RTO 210ms +.1 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7> +0 > S. 0:0(0) ack 1 <...> +.01 < . 1:1(0) ack 1 win 257 +0 accept(3, ..., ...) = 4 // Send 2 data segments +0 write(4, ..., 2000) = 2000 +0 > P. 1:2001(2000) ack 1 // TLP +.022 > P. 1001:2001(1000) ack 1 // Continue to send 8 data segments +0 write(4, ..., 10000) = 10000 +0 > P. 2001:10001(8000) ack 1 // RTO +.188 > . 1:1001(1000) ack 1 // The original data is acked and new data is sent(F-RTO step 2.b) +0 < . 1:1(0) ack 2001 win 257 +0 > P. 10001:12001(2000) ack 1 // D-SACK caused by TLP is regarded as a dupack, this results in // the incorrect judgment of "loss was real"(F-RTO step 3.a) +.022 < . 1:1(0) ack 2001 win 257 <sack 1001:2001,nop,nop> // Never-retransmitted data(3001:4001) are acked and // expect to switch to open state(F-RTO step 3.b) +0 < . 1:1(0) ack 4001 win 257 +0 %{ assert tcpi_ca_state == 0, tcpi_ca_state }% Fixes: e33099f96d ("tcp: implement RFC5682 F-RTO") Signed-off-by: Pengcheng Yang <yangpc@wangsu.com> Acked-by: Neal Cardwell <ncardwell@google.com> Tested-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/1650967419-2150-1-git-send-email-yangpc@wangsu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-05-09 09:05:06 +02:00
..
6lowpan	6lowpan: iphc: Fix an off-by-one check of array index	2021-09-15 09:50:34 +02:00
9p	xen/9p: use alloc/free_pages_exact()	2022-03-11 12:11:54 +01:00
802	net/802/garp: fix memleak in garp_request_join()	2021-07-31 08:16:11 +02:00
8021q	net: vlan: fix underflow for the real_dev refcnt	2021-12-01 09:19:08 +01:00
appletalk	appletalk: Fix skb allocation size in loopback case	2021-04-07 15:00:08 +02:00
atm	net: atm: fix update of position index in lec_seq_next	2020-10-31 12:26:30 -07:00
ax25	ax25: Fix UAF bugs in ax25 timers	2022-04-20 09:23:32 +02:00
batman-adv	ipv6: make mc_forwarding atomic	2022-04-13 21:00:56 +02:00
bluetooth	Bluetooth: Fix use after free in hci_send_acl	2022-04-13 21:01:00 +02:00
bpf	bpf, test, cgroup: Use sk_{alloc,free} for test cases	2021-10-27 09:56:56 +02:00
bpfilter	bpfilter: Specify the log level for the kmsg message	2021-07-14 16:56:29 +02:00
bridge	net: bridge: vlan: fix memory leak in __allowed_ingress	2022-02-01 17:25:48 +01:00
caif	net-caif: avoid user-triggerable WARN_ON(1)	2021-09-22 12:27:56 +02:00
can	can: isotp: stop timeout monitoring when no first frame was sent	2022-04-27 13:53:57 +02:00
ceph	libceph: clear con->out_msg on Policy::stateful_server faults	2020-10-12 15:29:27 +02:00
core	bpf, lwt: Fix crash when using bpf_skb_set_tunnel_key() from bpf_xmit lwt hook	2022-05-09 09:05:02 +02:00
dcb	net: dcb: disable softirqs in dcbnl_flush_dev()	2022-03-08 19:09:37 +01:00
dccp	tcp: switch orphan_count to bare per-cpu counters	2021-11-18 14:04:08 +01:00
decnet	net: decnet: Fix sleeping inside in af_decnet	2021-07-28 14:35:38 +02:00
dns_resolver	docs: networking: convert dns_resolver.txt to ReST	2020-04-28 14:39:46 -07:00
dsa	net: dsa: Add missing of_node_put() in dsa_port_link_register_of	2022-05-09 09:05:02 +02:00
ethernet	net: move devres helpers into a separate source file	2020-05-23 16:56:17 -07:00
ethtool	ethtool: do not perform operations on net devices being unregistered	2021-12-17 10:14:41 +01:00
hsr	net: hsr: fix mac_len checks	2021-06-03 09:00:50 +02:00
ieee802154	net: ieee802154: Return meaningful error codes from the netlink helpers	2022-02-08 18:30:37 +01:00
ife	net: Fix Kconfig indentation	2019-09-26 08:56:17 +02:00
ipv4	tcp: fix F-RTO may not work correctly when receiving DSACK	2022-05-09 09:05:06 +02:00
ipv6	tcp: make sure treq->af_specific is initialized	2022-05-09 09:05:04 +02:00
iucv	net/af_iucv: remove WARN_ONCE on malformed RX packets	2021-03-07 12:34:05 +01:00
kcm	net: pass a sockptr_t into ->setsockopt	2020-07-24 15:41:54 -07:00
key	af_key: add __GFP_ZERO flag for compose_sadb_supported in function pfkey_register	2022-04-08 14:39:48 +02:00
l2tp	net/l2tp: Fix reference count leak in l2tp_udp_recv_core	2021-09-22 12:27:56 +02:00
l3mdev	l3mdev: l3mdev_master_upper_ifindex_by_index_rcu should be using netdev_master_upper_dev_get_rcu	2022-04-27 13:53:50 +02:00
lapb	net: lapb: Copy the skb before sending a packet	2021-02-10 09:29:14 +01:00
llc	llc: only change llc->dev when bind() succeeds	2022-03-28 09:57:10 +02:00
mac80211	mac80211: fix potential double free on mesh join	2022-03-28 09:57:10 +02:00
mac802154	net: mac802154: Fix general protection fault	2021-04-14 08:42:13 +02:00
mpls	net: mpls: Fix notifications when deleting a device	2021-12-08 09:03:23 +01:00
mptcp	mptcp: clear 'kern' flag from fallback sockets	2021-12-22 09:30:54 +01:00
ncsi	net/ncsi: check for error return from call to nla_put_u32	2022-01-05 12:40:32 +01:00
netfilter	netfilter: nft_set_rbtree: overlap detection with element re-addition after deletion	2022-05-09 09:05:02 +02:00
netlabel	netlabel: fix out-of-bounds memory accesses	2022-04-13 21:01:00 +02:00
netlink	netlink: reset network and mac headers in netlink_dump()	2022-04-27 13:53:51 +02:00
netrom	netrom: fix api breakage in nr_setsockopt()	2022-01-27 10:54:03 +01:00
nfc	nfc: nci: add flush_workqueue to prevent uaf	2022-04-20 09:23:18 +02:00
nsh	treewide: replace '---help---' in Kconfig files with 'help'	2020-06-14 01:57:21 +09:00
openvswitch	openvswitch: fix OOB access in reserve_sfa_size()	2022-04-27 13:53:55 +02:00
packet	net/packet: fix packet_sock xmit return value checking	2022-04-27 13:53:50 +02:00
phonet	phonet: refcount leak in pep_sock_accep	2022-01-11 15:25:01 +01:00
psample	net: psample: Fix netlink skb length with tunnel info	2021-03-07 12:34:07 +01:00
qrtr	net: qrtr: fix another OOB Read in qrtr_endpoint_post	2021-09-03 10:09:21 +02:00
rds	rds: memory leak in __rds_conn_create()	2021-12-22 09:30:54 +01:00
rfkill	rfkill: Fix use-after-free in rfkill_resume()	2020-11-12 09:18:06 +01:00
rose	rose: Fix Null pointer dereference in rose_send_frame()	2020-11-20 10:04:58 -08:00
rxrpc	rxrpc: Restore removed timer deletion	2022-04-27 13:53:49 +02:00
sched	net/sched: cls_u32: fix possible leak in u32_init_knode()	2022-04-27 13:53:50 +02:00
sctp	sctp: check asoc strreset_chunk in sctp_generate_reconf_event	2022-05-09 09:05:03 +02:00
smc	net/smc: sync err code when tcp connection was refused	2022-05-09 09:05:04 +02:00
strparser	bpf: sockmap, strparser, and tls are reusing qdisc_skb_cb and colliding	2021-11-18 14:04:27 +01:00
sunrpc	SUNRPC: svc_tcp_sendmsg() should handle errors from xdr_alloc_bvec()	2022-04-13 21:01:07 +02:00
switchdev	net: switchdev: don't set port_obj_info->handled true when -EOPNOTSUPP	2021-02-07 15:37:12 +01:00
tipc	tipc: fix the timer expires after interval 100ms	2022-04-08 14:40:23 +02:00
tls	tls: Skip tls_append_frag on zero copy size	2022-05-09 09:05:05 +02:00
unix	af_unix: annote lockless accesses to unix_tot_inflight & gc_in_progress	2022-01-27 10:54:31 +01:00
vmw_vsock	vsock: each transport cycles only on its own sockets	2022-03-23 09:13:27 +01:00
wimax	genetlink: move to smaller ops wherever possible	2020-10-02 19:11:11 -07:00
wireless	nl80211: correctly check NL80211_ATTR_REG_ALPHA2 size	2022-04-20 09:23:28 +02:00
x25	net/x25: Fix null-ptr-deref caused by x25_disconnect	2022-04-08 14:40:30 +02:00
xdp	Revert "xsk: Do not sleep in poll() when need_wakeup set"	2021-12-22 09:30:59 +01:00
xfrm	xfrm: fix tunnel model fragmentation behavior	2022-04-08 14:39:47 +02:00
compat.c	net: Return the correct errno code	2021-06-18 10:00:06 +02:00
devres.c	net: devres: rename the release callback of devm_register_netdev()	2020-06-30 15:57:34 -07:00
Kconfig	drop_monitor: Convert to using devlink tracepoint	2020-09-30 18:01:26 -07:00
Makefile	net: move devres helpers into a separate source file	2020-05-23 16:56:17 -07:00
socket.c	ethtool: improve compat ioctl handling	2021-09-18 13:40:21 +02:00
sysctl_net.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00