This test checks TCP behavior when receiving a packet beyond the window. It checks the new TcpExtBeyondWindow SNMP counter. Signed-off-by: Eric Dumazet --- .../net/packetdrill/tcp_rcv_big_endseq.pkt | 44 +++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 tools/testing/selftests/net/packetdrill/tcp_rcv_big_endseq.pkt diff --git a/tools/testing/selftests/net/packetdrill/tcp_rcv_big_endseq.pkt b/tools/testing/selftests/net/packetdrill/tcp_rcv_big_endseq.pkt new file mode 100644 index 0000000000000000000000000000000000000000..7e170b94fd366ef516d68cf97bf921fdbf437ca8 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp_rcv_big_endseq.pkt @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 + +--mss=1000 + +`./defaults.sh` + + 0 `nstat -n` + +// Establish a connection. + +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 + +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 + +0 setsockopt(3, SOL_SOCKET, SO_RCVBUF, [10000], 4) = 0 + +0 bind(3, ..., ...) = 0 + +0 listen(3, 1) = 0 + + +0 < S 0:0(0) win 32792 + +0 > S. 0:0(0) ack 1 + +.1 < . 1:1(0) ack 1 win 257 + + +0 accept(3, ..., ...) = 4 + + +0 < P. 1:4001(4000) ack 1 win 257 + +0 > . 1:1(0) ack 4001 win 5000 + +// packet in sequence : SKB_DROP_REASON_TCP_INVALID_END_SEQUENCE / LINUX_MIB_BEYOND_WINDOW + +0 < P. 4001:54001(50000) ack 1 win 257 + +0 > . 1:1(0) ack 4001 win 5000 + +// ooo packet. : SKB_DROP_REASON_TCP_INVALID_END_SEQUENCE / LINUX_MIB_BEYOND_WINDOW + +1 < P. 5001:55001(50000) ack 1 win 257 + +0 > . 1:1(0) ack 4001 win 5000 + +// SKB_DROP_REASON_TCP_INVALID_SEQUENCE / LINUX_MIB_BEYOND_WINDOW + +0 < P. 70001:80001(10000) ack 1 win 257 + +0 > . 1:1(0) ack 4001 win 5000 + + +0 read(4, ..., 100000) = 4000 + +// If queue is empty, accept a packet even if its end_seq is above wup + rcv_wnd + +0 < P. 4001:54001(50000) ack 1 win 257 + +.040 > . 1:1(0) ack 54001 win 0 + +// Check LINUX_MIB_BEYOND_WINDOW has been incremented 3 times. ++0 `nstat | grep TcpExtBeyondWindow | grep -q " 3 "` -- 2.50.0.727.gbf7dc18ff4-goog