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Yonglong Li 536a6c8e05 tcp: make retransmitted SKB fit into the send window
current code of __tcp_retransmit_skb only check TCP_SKB_CB(skb)->seq
in send window, and TCP_SKB_CB(skb)->seq_end maybe out of send window.
If receiver has shrunk his window, and skb is out of new window,  it
should retransmit a smaller portion of the payload.

test packetdrill script:
    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
   +0 fcntl(3, F_GETFL) = 0x2 (flags O_RDWR)
   +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0

   +0 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress)
   +0 > S 0:0(0)  win 65535 <mss 1460,sackOK,TS val 100 ecr 0,nop,wscale 8>
 +.05 < S. 0:0(0) ack 1 win 6000 <mss 1000,nop,nop,sackOK>
   +0 > . 1:1(0) ack 1

   +0 write(3, ..., 10000) = 10000

   +0 > . 1:2001(2000) ack 1 win 65535
   +0 > . 2001:4001(2000) ack 1 win 65535
   +0 > . 4001:6001(2000) ack 1 win 65535

 +.05 < . 1:1(0) ack 4001 win 1001

and tcpdump show:
192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 1:2001, ack 1, win 65535, length 2000
192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 2001:4001, ack 1, win 65535, length 2000
192.168.226.67.55 > 192.0.2.1.8080: Flags [P.], seq 4001:5001, ack 1, win 65535, length 1000
192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 5001:6001, ack 1, win 65535, length 1000
192.0.2.1.8080 > 192.168.226.67.55: Flags [.], ack 4001, win 1001, length 0
192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 5001:6001, ack 1, win 65535, length 1000
192.168.226.67.55 > 192.0.2.1.8080: Flags [P.], seq 4001:5001, ack 1, win 65535, length 1000

when cient retract window to 1001, send window is [4001,5002],
but TLP send 5001-6001 packet which is out of send window.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/1657532838-20200-1-git-send-email-liyonglong@chinatelecom.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-12 18:13:48 -07:00
arch arch: arm64: dts: marvell: rename the sfp GPIO properties 2022-07-12 17:27:17 -07:00
block block: remove WARN_ON() from bd_link_disk_holder 2022-06-23 07:48:05 -06:00
certs Certs changes 2022-06-21 12:13:53 -05:00
crypto crypto: s390 - do not depend on CRYPTO_HW for SIMD implementations 2022-07-06 20:04:06 -07:00
Documentation dt-bindings: net: sff,sfp: rename example dt nodes to be more generic 2022-07-12 17:27:16 -07:00
drivers nfp: support TX VLAN ctag insert in NFDK 2022-07-12 18:09:57 -07:00
fs Fixes for 5.19-rc5: 2022-07-03 09:42:17 -07:00
include net: change the type of ip_route_input_rcu to static 2022-07-12 15:08:45 +02:00
init gcc-12: disable '-Warray-bounds' universally for now 2022-06-09 10:11:12 -07:00
ipc These changes update the ipc sysctls so that they are fundamentally 2022-06-03 15:54:57 -07:00
kernel Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2022-07-09 12:24:16 -07:00
lib Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2022-07-09 12:24:16 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm Minor things, mainly - mailmap updates, MAINTAINERS updates, etc. 2022-06-26 14:00:55 -07:00
net tcp: make retransmitted SKB fit into the send window 2022-07-12 18:13:48 -07:00
samples Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2022-07-09 12:24:16 -07:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-06-30 16:31:00 -07:00
security selinux: free contexts previously transferred in selinux_add_opt() 2022-06-15 21:20:45 -04:00
sound ALSA: cs46xx: Fix missing snd_card_free() call at probe error 2022-07-05 17:24:05 +02:00
tools selftests: tls: add test for NoPad getsockopt 2022-07-11 19:48:33 -07:00
usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt KVM: x86: disable preemption around the call to kvm_arch_vcpu_{un|}blocking 2022-06-09 10:52:20 -04:00
.clang-format clang-format: Fix space after for_each macros 2022-05-20 19:27:16 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: split the second line of *.mod into *.usyms 2022-05-08 03:16:59 +09:00
.mailmap mailmap: add entry for Christian Marangi 2022-06-16 19:11:32 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS dt-bindings: net: convert sff,sfp to dtschema 2022-07-12 17:27:16 -07:00
Makefile Linux 5.19-rc5 2022-07-03 15:39:28 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.