TencentOS-kernel/net
Ryan Sharpelletti afcd3ea8af tcp: only postpone PROBE_RTT if RTT is < current min_rtt estimate
[ Upstream commit 1b9e2a8c99a5c021041bfb2d512dc3ed92a94ffd ]

During loss recovery, retransmitted packets are forced to use TCP
timestamps to calculate the RTT samples, which have a millisecond
granularity. BBR is designed using a microsecond granularity. As a
result, multiple RTT samples could be truncated to the same RTT value
during loss recovery. This is problematic, as BBR will not enter
PROBE_RTT if the RTT sample is <= the current min_rtt sample, meaning
that if there are persistent losses, PROBE_RTT will constantly be
pushed off and potentially never re-entered. This patch makes sure
that BBR enters PROBE_RTT by checking if RTT sample is < the current
min_rtt sample, rather than <=.

The Netflix transport/TCP team discovered this bug in the Linux TCP
BBR code during lab tests.

Fixes: 0f8782ea1497 ("tcp_bbr: add BBR congestion control")
Signed-off-by: Ryan Sharpelletti <sharpelletti@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Link: https://lore.kernel.org/r/20201116174412.1433277-1-sharpelletti.kdev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:41:08 +08:00
..
6lowpan Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
9p net: 9p: initialize sun_server.sun_path to have addr's value only when addr is valid 2021-03-16 16:39:51 +08:00
802 Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
8021q Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
appletalk appletalk: Fix atalk_proc_init() return path 2021-03-16 16:33:09 +08:00
atm atm: fix a memory leak of vcc->user_back 2021-03-16 16:37:15 +08:00
ax25 AX.25: Prevent integer overflows in connect and sendmsg 2021-03-16 16:32:42 +08:00
batman-adv batman-adv: mcast: fix duplicate mcast packets from BLA backbone to mesh 2021-03-16 16:37:35 +08:00
bluetooth Bluetooth: Only mark socket zapped after unlocking 2021-03-16 16:39:20 +08:00
bpf Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
bpfilter net/bpfilter: remove superfluous testing message 2021-03-16 16:26:23 +08:00
bridge net: bridge: add missing counters to ndo_get_stats64 callback 2021-03-16 16:41:05 +08:00
caif Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
can can: proc: can_remove_proc(): silence remove_proc_entry warning 2021-03-16 16:41:03 +08:00
ceph libceph: clear con->out_msg on Policy::stateful_server faults 2021-03-16 16:40:11 +08:00
core net: Have netpoll bring-up DSA management interface 2021-03-16 16:41:06 +08:00
dcb net: DCB: Validate DCB_ATTR_DCB_BUFFER argument 2021-03-16 16:36:26 +08:00
dccp dccp: Fix possible memleak in dccp_init and dccp_fini 2021-03-16 16:29:07 +08:00
decnet Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
dns_resolver KEYS: Don't write out to userspace while holding key semaphore 2021-03-16 16:26:42 +08:00
dsa dsa: Allow forwarding of redirected IGMP traffic 2021-03-16 16:36:11 +08:00
ethernet Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
hsr hsr: check protocol version in hsr_newlink() 2021-03-16 16:26:20 +08:00
ieee802154 Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ife Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ipv4 tcp: only postpone PROBE_RTT if RTT is < current min_rtt estimate 2021-03-16 16:41:08 +08:00
ipv6 ipv6: Fix error path to cancel the meseage 2021-03-16 16:41:04 +08:00
iucv Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
kcm Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
key af_key: pfkey_dump needs parameter validation 2021-03-16 16:36:23 +08:00
l2tp l2tp: remove skb_dst_set() from l2tp_xmit_skb() 2021-03-16 16:31:43 +08:00
l3mdev Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
lapb Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
llc net: silence data-races on sk_backlog.tail 2021-03-16 16:36:36 +08:00
mac80211 mac80211: always wind down STA state 2021-03-16 16:41:02 +08:00
mac802154 mac802154: tx: fix use-after-free 2021-03-16 16:37:33 +08:00
mpls Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ncsi Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
netfilter netfilter: ipset: Update byte and packet counters regardless of whether they match 2021-03-16 16:40:35 +08:00
netlabel netlabel: fix an uninitialized warning in netlbl_unlabel_staticlist() 2021-03-16 16:41:06 +08:00
netlink genetlink: remove genl_bind 2021-03-16 16:31:42 +08:00
netrom net: netrom: Fix potential nr_neigh refcnt leak in nr_add_node 2021-03-16 16:26:51 +08:00
nfc nfc: Ensure presence of NFC_ATTR_FIRMWARE_NAME attribute in nfc_genl_fw_download() 2021-03-16 16:38:18 +08:00
nsh Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
openvswitch openvswitch: handle DNAT tuple collision 2021-03-16 16:38:00 +08:00
packet af_packet: TPACKET_V3: fix fill status rwlock imbalance 2021-03-16 16:33:48 +08:00
phonet Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
psample Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
qrtr net: qrtr: check skb_put_padto() return value 2021-03-16 16:36:30 +08:00
rds rds: Prevent kernel-infoleak in rds_notify_queue_get() 2021-03-16 16:32:48 +08:00
rfkill Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
rose Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
rxrpc rxrpc: Fix server keyring leak 2021-03-16 16:38:05 +08:00
sched net: sch_generic: fix the missing new qdisc assignment bug 2021-03-16 16:41:00 +08:00
sctp sctp: change to hold/put transport for proto_unreach_timer 2021-03-16 16:41:08 +08:00
smc net/smc: fix direct access to ib_gid_addr->ndev in smc_ib_determine_gid() 2021-03-16 16:41:07 +08:00
strparser Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
sunrpc SUNRPC: Mitigate cond_resched() in xprt_transmit() 2021-03-16 16:39:47 +08:00
switchdev Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
tipc tipc: fix memory leak in tipc_topsrv_start() 2021-03-16 16:40:58 +08:00
tls net/tls: fix corrupted data in recvmsg 2021-03-16 16:41:07 +08:00
toa Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
unix skbuff: fix a data race in skb_queue_len() 2021-03-16 16:36:50 +08:00
vmw_vsock vsock: use ns_capable_noaudit() on socket create 2021-03-16 16:40:26 +08:00
wimax Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
wireless cfg80211: regulatory: Fix inconsistent format argument 2021-03-16 16:40:44 +08:00
x25 net: x25: Increase refcnt of "struct x25_neigh" in x25_rx_call_request 2021-03-16 16:41:07 +08:00
xdp xdp: Fix xsk_generic_xmit errno 2021-03-16 16:30:35 +08:00
xfrm net: xfrm: fix a race condition during allocing spi 2021-03-16 16:40:34 +08:00
Kconfig Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Makefile Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
compat.c net/compat: Add missing sock updates for SCM_RIGHTS 2021-03-16 16:34:05 +08:00
socket.c net: Set fput_needed iff FDPUT_FPUT is set 2021-03-16 16:33:49 +08:00
sysctl_net.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00