tools/testing/selftests/net/packetdrill/tcp_ooo-before-and-after-accept.pkt

Source file repositories/reference/linux-study-clean/tools/testing/selftests/net/packetdrill/tcp_ooo-before-and-after-accept.pkt

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/net/packetdrill/tcp_ooo-before-and-after-accept.pkt
Extension
.pkt
Size
1715 bytes
Lines
54
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: tools
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0

--mss=1000

`./defaults.sh
sysctl -q net.ipv4.tcp_rmem="4096 131072 $((32*1024*1024))"`

// Test that a not-yet-accepted socket does not change
// its initial sk_rcvbuf (tcp_rmem[1]) when receiving ooo packets.

   +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

   +0 < S 0:0(0) win 65535 <mss 1000,nop,nop,sackOK,nop,wscale 7>
   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 10>
  +.1 < . 1:1(0) ack 1 win 257
  +0  < . 2001:41001(39000) ack 1 win 257
  +0  > . 1:1(0) ack 1 <nop,nop,sack 2001:41001>
  +0  < . 41001:101001(60000) ack 1 win 257
  +0  > . 1:1(0) ack 1 <nop,nop,sack 2001:101001>
  +0  < . 1:1001(1000) ack 1 win 257
  +0  > . 1:1(0) ack 1001 <nop,nop,sack 2001:101001>
  +0  < . 1001:2001(1000) ack 1 win 257
  +0  > . 1:1(0) ack 101001

  +0 accept(3, ..., ...) = 4

  +0 %{ assert SK_MEMINFO_RCVBUF == 131072, SK_MEMINFO_RCVBUF }%

  +0 close(4) = 0
  +0 close(3) = 0

// Test that ooo packets for accepted sockets do increase sk_rcvbuf
   +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

   +0 < S 0:0(0) win 65535 <mss 1000,nop,nop,sackOK,nop,wscale 7>
   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 10>
  +.1 < . 1:1(0) ack 1 win 257

   +0 accept(3, ..., ...) = 4

  +0  < . 2001:41001(39000) ack 1 win 257
  +0  > . 1:1(0) ack 1 <nop,nop,sack 2001:41001>
  +0  < . 41001:101001(60000) ack 1 win 257
  +0  > . 1:1(0) ack 1 <nop,nop,sack 2001:101001>

  +0 %{ assert SK_MEMINFO_RCVBUF > 131072, SK_MEMINFO_RCVBUF }%

Annotation

Implementation Notes