| // SPDX-License-Identifier: GPL-2.0 |
| // Test maximum advertised window limit when rcv_nxt advances past |
| // rcv_mwnd_seq. The "usable window" must be properly clamped to zero |
| // rather than becoming negative. |
| |
| --mss=1000 |
| |
| `./defaults.sh` |
| |
| // 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, [20000], 4) = 0 |
| +0 bind(3, ..., ...) = 0 |
| +0 listen(3, 1) = 0 |
| |
| +0 < S 0:0(0) win 32792 <mss 1000,nop,wscale 7> |
| +0 > S. 0:0(0) ack 1 win 18980 <mss 1460,nop,wscale 0> |
| +.1 < . 1:1(0) ack 1 win 257 |
| |
| +0 accept(3, ..., ...) = 4 |
| |
| // A too big packet is accepted if the receive queue is empty. It |
| // does not trigger an immediate ACK. |
| +0 < P. 1:20001(20000) ack 1 win 257 |
| +0 %{ assert tcpi_bytes_received == 20000, tcpi_bytes_received; }% |
| |
| // Send a RST immediately so that there is no rcv_wup/rcv_mwnd_seq update yet |
| +0 < R. 20001:20001(0) ack 1 win 257 |
| |
| // Verify that the RST was accepted. Indirectly this also verifies that no |
| // immediate ACK was sent for the data packet above. |
| +0 < . 20001:20001(0) ack 1 win 257 |
| +0 > R 1:1(0) |
