From: Simon Baatz <[email protected]> Add a packetdrill test that verifies we accept bare FIN packets when the advertised receive window is zero.
Signed-off-by: Simon Baatz <[email protected]> --- .../net/packetdrill/tcp_rcv_zero_wnd_fin.pkt | 27 ++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/tools/testing/selftests/net/packetdrill/tcp_rcv_zero_wnd_fin.pkt b/tools/testing/selftests/net/packetdrill/tcp_rcv_zero_wnd_fin.pkt new file mode 100644 index 0000000000000000000000000000000000000000..e245359a1a91d4b6d7ef64496681cea57792cb71 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp_rcv_zero_wnd_fin.pkt @@ -0,0 +1,27 @@ +// SPDX-License-Identifier: GPL-2.0 + +// Some TCP stacks send FINs even though the window is closed. We break +// a possible FIN/ACK loop by accepting the FIN. + +--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 <mss 1460,nop,wscale 0> + +0 < . 1:1(0) ack 1 win 257 + + +0 accept(3, ..., ...) = 4 + + +0 < P. 1:60001(60000) ack 1 win 257 + * > . 1:1(0) ack 60001 win 0 + + +0 < F. 60001:60001(0) ack 1 win 257 + +0 > . 1:1(0) ack 60002 win 0 -- 2.53.0
