diff options
| author | Eric Dumazet <edumazet@google.com> | 2026-03-13 14:54:29 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-03-14 23:15:46 +0300 |
| commit | 4686679a14d269d4f02533228e82de56f432bae5 (patch) | |
| tree | 7ee6fc1760017266036f68c5083a788fbc5b004f /tools/testing | |
| parent | 411ad060587591a2c8a6005b8e2f42d8a1dae2da (diff) | |
| download | linux-4686679a14d269d4f02533228e82de56f432bae5.tar.xz | |
selftests/net: packetdrill: add tcp_disorder_fin_in_FIN_WAIT.pkt
Commit 795a7dfbc3d9 ("net: tcp: accept old ack during closing")
was fixing an old bug, add a test to make sure we won't break
this case in future kernels.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Menglong Dong <menglong8.dong@gmail.com>
Link: https://patch.msgid.link/20260313115429.3365751-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'tools/testing')
| -rw-r--r-- | tools/testing/selftests/net/packetdrill/tcp_disorder_fin_in_FIN_WAIT.pkt | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/packetdrill/tcp_disorder_fin_in_FIN_WAIT.pkt b/tools/testing/selftests/net/packetdrill/tcp_disorder_fin_in_FIN_WAIT.pkt new file mode 100644 index 000000000000..336cbf7815c8 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp_disorder_fin_in_FIN_WAIT.pkt @@ -0,0 +1,33 @@ +// SPDX-License-Identifier: GPL-2.0 + +// Check fix in 795a7dfbc3d9 ("net: tcp: accept old ack during closing") + +// Set up config. +`./defaults.sh` + +// Initialize a server socket. + 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,sackOK,nop,nop,nop,wscale 7> + * > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> + +0 < . 1:1(0) ack 1 win 257 + + +0 accept(3, ..., ...) = 4 + + +0 shutdown(4, SHUT_WR) = 0 + * > F. 1:1(0) ack 1 + +// We expect to receive one ACK. +// But what happens if a FIN was already in transmt and received out-of-order ? + + +0 < . 2:2(0) ack 2 win 257 + +// This FIN packet was sent before the prior ACK (see ack 1). + +0 < F. 1:1(0) ack 1 win 257 + +// Even if the FIN is received out-of-order, we should ACK it. + + * > . 2:2(0) ack 2 |