Merge: [kselftest] packetdrill: add more tests and xfails all on debug kernel

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-10/-/merge_requests/1661

JIRA: https://issues.redhat.com/browse/RHEL-124166

 * 265c6ff selftests/net: packetdrill: more xfail changes
 * f0600fe selftests/net: packetdrill: add --mss option to three tests
 * 5ef7fdf selftests: net: packetdrill: xfail all problems on slow machines
 * a5c10aa selftests/net: packetdrill: Support single protocol test.
 * 70dd477 selftest: packetdrill: Set ktap_set_plan properly for single protocol test.
 * 261cb8b selftest: packetdrill: Require explicit setsockopt(TCP_FASTOPEN).
 * 97b3b83 selftest: packetdrill: Define common TCP Fast Open cookie.
 * 0b8f164 selftest: packetdrill: Import TFO server basic tests.
 * 399e0a7 selftest: packetdrill: Add test for TFO_SERVER_WO_SOCKOPT1.
 * e57b393 selftest: packetdrill: Add test for experimental option.
 * 5ed080f selftest: packetdrill: Import opt34/fin-close-socket.pkt.
 * a8b1750 selftest: packetdrill: Import opt34/icmp-before-accept.pkt.
 * 5920f15 selftest: packetdrill: Import opt34/reset-* tests.
 * 21f7fb3 selftest: packetdrill: Import opt34/*-trigger-rst.pkt.
 * 05b9f50 selftest: packetdrill: Import sockopt-fastopen-key.pkt
 * 9b62d53 selftest: packetdrill: Import client-ack-dropped-then-recovery-ms-timestamps.pkt

Signed-off-by: CKI Backport Bot <cki-ci-bot+cki-gitlab-backport-bot@redhat.com>

---

<small>Created 2025-10-27 06:37 UTC by backporter - [KWF FAQ](https://red.ht/kernel_workflow_doc) - [Slack #team-kernel-workflow](https://redhat-internal.slack.com/archives/C04LRUPMJQ5) - [Source](https://gitlab.com/cki-project/kernel-workflow/-/blob/main/webhook/utils/backporter.py) - [Documentation](https://gitlab.com/cki-project/kernel-workflow/-/blob/main/docs/README.backporter.md) - [Report an issue](https://issues.redhat.com/secure/CreateIssueDetails!init.jspa?pid=12334433&issuetype=1&priority=4&summary=backporter+webhook+issue&components=kernel-workflow+/+backporter)</small>

Approved-by: Davide Caratti <dcaratti@redhat.com>
Approved-by: Paolo Abeni <pabeni@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: Jan Stancek <jstancek@redhat.com>

Author: jstancek

tools/testing/selftests/net/packetdrill/defaults.sh

@@ -51,7 +51,8 @@ sysctl -q net.ipv4.tcp_pacing_ss_ratio=200
 sysctl -q net.ipv4.tcp_pacing_ca_ratio=120
 sysctl -q net.ipv4.tcp_notsent_lowat=4294967295 > /dev/null 2>&1
 
-sysctl -q net.ipv4.tcp_fastopen=0x70403
+sysctl -q net.ipv4.tcp_fastopen=0x3
+# Use TFO_COOKIE in ksft_runner.sh for this key.
 sysctl -q net.ipv4.tcp_fastopen_key=a1a1a1a1-b2b2b2b2-c3c3c3c3-d4d4d4d4
 
 sysctl -q net.ipv4.tcp_syncookies=1

tools/testing/selftests/net/packetdrill/ksft_runner.sh

@@ -3,21 +3,26 @@
 
 source "$(dirname $(realpath $0))/../../kselftest/ktap_helpers.sh"
 
-readonly ipv4_args=('--ip_version=ipv4 '
-		    '--local_ip=192.168.0.1 '
-		    '--gateway_ip=192.168.0.1 '
-		    '--netmask_ip=255.255.0.0 '
-		    '--remote_ip=192.0.2.1 '
-		    '-D CMSG_LEVEL_IP=SOL_IP '
-		    '-D CMSG_TYPE_RECVERR=IP_RECVERR ')
-
-readonly ipv6_args=('--ip_version=ipv6 '
-		    '--mtu=1520 '
-		    '--local_ip=fd3d:0a0b:17d6::1 '
-		    '--gateway_ip=fd3d:0a0b:17d6:8888::1 '
-		    '--remote_ip=fd3d:fa7b:d17d::1 '
-		    '-D CMSG_LEVEL_IP=SOL_IPV6 '
-		    '-D CMSG_TYPE_RECVERR=IPV6_RECVERR ')
+declare -A ip_args=(
+	[ipv4]="--ip_version=ipv4
+		--local_ip=192.168.0.1
+		--gateway_ip=192.168.0.1
+		--netmask_ip=255.255.0.0
+		--remote_ip=192.0.2.1
+		-D TFO_COOKIE=3021b9d889017eeb
+		-D TFO_COOKIE_ZERO=b7c12350a90dc8f5
+		-D CMSG_LEVEL_IP=SOL_IP
+		-D CMSG_TYPE_RECVERR=IP_RECVERR"
+	[ipv6]="--ip_version=ipv6
+		--mtu=1520
+		--local_ip=fd3d:0a0b:17d6::1
+		--gateway_ip=fd3d:0a0b:17d6:8888::1
+		--remote_ip=fd3d:fa7b:d17d::1
+		-D TFO_COOKIE=c1d1e9742a47a9bc
+		-D TFO_COOKIE_ZERO=82af1a8f9a205c34
+		-D CMSG_LEVEL_IP=SOL_IPV6
+		-D CMSG_TYPE_RECVERR=IPV6_RECVERR"
+)
 
 if [ $# -ne 1 ]; then
 	ktap_exit_fail_msg "usage: $0 <script>"
@@ -35,28 +40,23 @@ failfunc=ktap_test_fail
 
 if [[ -n "${KSFT_MACHINE_SLOW}" ]]; then
 	optargs+=('--tolerance_usecs=14000')
+	failfunc=ktap_test_xfail
+fi
 
-	# xfail tests that are known flaky with dbg config, not fixable.
-	# still run them for coverage (and expect 100% pass without dbg).
-	declare -ar xfail_list=(
-		"tcp_eor_no-coalesce-retrans.pkt"
-		"tcp_fast_recovery_prr-ss.*.pkt"
-		"tcp_slow_start_slow-start-after-win-update.pkt"
-		"tcp_timestamping.*.pkt"
-		"tcp_user_timeout_user-timeout-probe.pkt"
-		"tcp_zerocopy_epoll_.*.pkt"
-		"tcp_tcp_info_tcp-info-.*-limited.pkt"
-	)
-	readonly xfail_regex="^($(printf '%s|' "${xfail_list[@]}"))$"
-	[[ "$script" =~ ${xfail_regex} ]] && failfunc=ktap_test_xfail
+ip_versions=$(grep -E '^--ip_version=' $script | cut -d '=' -f 2)
+if [[ -z $ip_versions ]]; then
+	ip_versions="ipv4 ipv6"
+elif [[ ! "$ip_versions" =~ ^ipv[46]$ ]]; then
+	ktap_exit_fail_msg "Too many or unsupported --ip_version: $ip_versions"
+	exit "$KSFT_FAIL"
 fi
 
 ktap_print_header
-ktap_set_plan 2
+ktap_set_plan $(echo $ip_versions | wc -w)
 
-unshare -n packetdrill ${ipv4_args[@]} ${optargs[@]} $script > /dev/null \
-	&& ktap_test_pass "ipv4" || $failfunc "ipv4"
-unshare -n packetdrill ${ipv6_args[@]} ${optargs[@]} $script > /dev/null \
-	&& ktap_test_pass "ipv6" || $failfunc "ipv6"
+for ip_version in $ip_versions; do
+	unshare -n packetdrill ${ip_args[$ip_version]} ${optargs[@]} $script > /dev/null \
+		&& ktap_test_pass $ip_version || $failfunc $ip_version
+done
 
 ktap_finished

tools/testing/selftests/net/packetdrill/tcp_blocking_blocking-read.pkt

@@ -1,6 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0
 // Test for blocking read.
+
 --tolerance_usecs=10000
+--mss=1000
 
 `./defaults.sh`
 

tools/testing/selftests/net/packetdrill/tcp_fastopen_server_basic-cookie-not-reqd.pkt

@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Basic TFO server test
+//
+// Test TFO_SERVER_COOKIE_NOT_REQD flag on receiving
+// SYN with data but without Fast Open cookie option.
+
+`./defaults.sh
+ ./set_sysctls.py /proc/sys/net/ipv4/tcp_fastopen=0x202`
+
+    0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+   +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [1], 4) = 0
+
+// Since TFO_SERVER_COOKIE_NOT_REQD, a TFO socket will be created with
+// the data accepted.
+   +0 < S 0:1000(1000) win 32792 <mss 1460,sackOK,nop,nop>
+   +0 > S. 0:0(0) ack 1001 <mss 1460,nop,nop,sackOK>
+   +0 accept(3, ..., ...) = 4
+   +0 %{ assert (tcpi_options & TCPI_OPT_SYN_DATA) != 0, tcpi_options }%
+   +0 read(4, ..., 1024) = 1000
+
+// Data After SYN will be accepted too.
+   +0 < . 1001:2001(1000) ack 1 win 5840
+   +0 > . 1:1(0) ack 2001
+
+// Should change the implementation later to set the SYN flag as well.
+   +0 read(4, ..., 1024) = 1000
+   +0 write(4, ..., 1000) = 1000
+   +0 > P. 1:1001(1000) ack 2001

tools/testing/selftests/net/packetdrill/tcp_fastopen_server_basic-no-setsockopt.pkt

@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Basic TFO server test
+//
+// Test TFO_SERVER_WO_SOCKOPT1 without setsockopt(TCP_FASTOPEN)
+
+`./defaults.sh
+ ./set_sysctls.py /proc/sys/net/ipv4/tcp_fastopen=0x402`
+
+    0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+
+   +0 < S 0:10(10) win 32792 <mss 1460,sackOK,nop,nop,FO TFO_COOKIE,nop,nop>
+   +0 > S. 0:0(0) ack 11 <mss 1460,nop,nop,sackOK>
+
+   +0 accept(3, ..., ...) = 4
+   +0 %{ assert (tcpi_options & TCPI_OPT_SYN_DATA) != 0, tcpi_options }%
+
+   +0 read(4, ..., 512) = 10

tools/testing/selftests/net/packetdrill/tcp_fastopen_server_basic-non-tfo-listener.pkt

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Basic TFO server test
+//
+// Server w/o TCP_FASTOPEN socket option
+
+`./defaults.sh`
+
+    0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+
+   +0 < S 0:10(10) win 32792 <mss 1460,sackOK,FO TFO_COOKIE>
+
+// Data is ignored since TCP_FASTOPEN is not set on the listener
+   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK>
+
+   +0 accept(3, ..., ...) = -1 EAGAIN (Resource temporarily unavailable)
+
+// The above should block until ack comes in below.
+   +0 < . 1:31(30) ack 1 win 5840
+   +0 accept(3, ..., ...) = 4
+
+   +0 %{ assert (tcpi_options & TCPI_OPT_SYN_DATA) == 0, tcpi_options }%
+   +0 read(4, ..., 512) = 30

tools/testing/selftests/net/packetdrill/tcp_fastopen_server_basic-pure-syn-data.pkt

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Basic TFO server test
+//
+// Test that TFO-enabled server would not respond SYN-ACK with any TFO option
+// when receiving a pure SYN-data. It should respond a pure SYN-ack.
+
+`./defaults.sh`
+
+    0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+   +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [1], 4) = 0
+
+   +0 < S 999000:999040(40) win 32792 <mss 1460,sackOK,TS val 100 ecr 100,nop,wscale 6>
+   +0 > S. 1234:1234(0) ack 999001 <mss 1460,sackOK,TS val 100 ecr 100,nop,wscale 8>
+   +0 < . 1:1(0) ack 1 win 100
+   +0 accept(3, ..., ...) = 4
+   +0 %{ assert (tcpi_options & TCPI_OPT_SYN_DATA) == 0, tcpi_options }%
+   +0 close(3) = 0
+
+// Test ECN-setup SYN with ECN disabled because this has happened in reality
+   +0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+   +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [1], 4) = 0
+
+   +0 < SEW 999000:999040(40) win 32792 <mss 1460,sackOK,TS val 100 ecr 100,nop,wscale 6>
+   +0 > S. 1234:1234(0) ack 999001 <mss 1460,sackOK,TS val 100 ecr 100,nop,wscale 8>
+   +0 < . 1:1(0) ack 1 win 100
+   +0 accept(3, ..., ...) = 4
+   +0 %{ assert (tcpi_options & TCPI_OPT_SYN_DATA) == 0, tcpi_options }%
+   +0 close(3) = 0
+
+// Test ECN-setup SYN w/ ECN enabled
+   +0 `sysctl -q net.ipv4.tcp_ecn=2`
+   +0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+   +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [1], 4) = 0
+
+   +0 < SEW 999000:999040(40) win 32792 <mss 1460,sackOK,TS val 100 ecr 100,nop,wscale 6>
+   +0 > SE. 1234:1234(0) ack 999001 <mss 1460,sackOK,TS val 100 ecr 100,nop,wscale 8>
+   +0 < . 1:1(0) ack 1 win 100
+   +0 accept(3, ..., ...) = 4
+   +0 %{ assert (tcpi_options & TCPI_OPT_SYN_DATA) == 0, tcpi_options }%
+   +0 close(3) = 0

tools/testing/selftests/net/packetdrill/tcp_fastopen_server_basic-rw.pkt

@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Basic TFO server test
+//
+// Test TFO server with SYN that has TFO cookie and data.
+
+`./defaults.sh`
+
+    0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+   +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [1], 4) = 0
+
+   +0 < S 0:10(10) win 32792 <mss 1460,sackOK,nop,nop,FO TFO_COOKIE,nop,nop>
+   +0 > S. 0:0(0) ack 11 <mss 1460,nop,nop,sackOK>
+
+   +0 accept(3, ..., ...) = 4
+   +0 %{ assert (tcpi_options & TCPI_OPT_SYN_DATA) != 0, tcpi_options }%
+
+   +0 read(4, ..., 512) = 10
+   +0 write(4, ..., 100) = 100
+   +0 > P. 1:101(100) ack 11

tools/testing/selftests/net/packetdrill/tcp_fastopen_server_basic-zero-payload.pkt

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Basic TFO server test
+//
+// Test zero-payload packet w/ valid TFO cookie - a TFO socket will
+// still be created and accepted but read() will not return until a
+// later pkt with 10 byte.
+
+`./defaults.sh`
+
+    0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+   +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [1], 4) = 0
+
+   +0 < S 0:0(0) win 32792 <mss 1460,sackOK,nop,nop,FO TFO_COOKIE,nop,nop>
+   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK>
+   +0 accept(3, ..., ...) = 4
+   +0 %{ assert (tcpi_options & TCPI_OPT_SYN_DATA) == 0, tcpi_options }%
+
+// A TFO socket is created and is writable.
+   +0 write(4, ..., 100) = 100
+   +0 > P. 1:101(100) ack 1
+   +0...0.300 read(4, ..., 512) = 10
+  +.3 < P. 1:11(10) ack 1 win 5840

tools/testing/selftests/net/packetdrill/tcp_fastopen_server_client-ack-dropped-then-recovery-ms-timestamps.pkt

@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// A reproducer case for a TFO SYNACK RTO undo bug in:
+//   794200d66273 ("tcp: undo cwnd on Fast Open spurious SYNACK retransmit")
+// This sequence that tickles this bug is:
+//  - Fast Open server receives TFO SYN with data, sends SYNACK
+//  - (client receives SYNACK and sends ACK, but ACK is lost)
+//  - server app sends some data packets
+//  - (N of the first data packets are lost)
+//  - server receives client ACK that has a TS ECR matching first SYNACK,
+//    and also SACKs suggesting the first N data packets were lost
+//     - server performs undo of SYNACK RTO, then immediately enters recovery
+//     - buggy behavior in 794200d66273 then performed an undo that caused
+//       the connection to be in a bad state, in CA_Open with retrans_out != 0
+
+// Check that outbound TS Val ticks are as we would expect with 1000 usec per
+// timestamp tick:
+--tcp_ts_tick_usecs=1000
+
+`./defaults.sh`
+
+// Initialize connection
+    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+   +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [1], 4) = 0
+   +0 bind(3, ..., ...) = 0
+   +0 listen(3, 1) = 0
+
+   +0 < S 0:1000(1000) win 65535 <mss 1012,sackOK,TS val 1000 ecr 0,wscale 7,nop,nop,nop,FO TFO_COOKIE>
+   +0 > S. 0:0(0) ack 1001 <mss 1460,sackOK,TS val 2000 ecr 1000,nop,wscale 8>
+   +0 accept(3, ..., ...) = 4
+
+// Application writes more data
+   +.010 write(4, ..., 10000) = 10000
+   +0 > P. 1:5001(5000) ack 1001 <nop,nop,TS val 2010 ecr 1000>
+   +0 > P. 5001:10001(5000) ack 1001 <nop,nop,TS val 2010 ecr 1000>
+   +0 %{ assert tcpi_snd_cwnd == 10, tcpi_snd_cwnd }%
+
+   +0 < . 1001:1001(0) ack 1 win 257 <TS val 1010 ecr 2000,sack 2001:5001>
+   +0 > P. 1:2001(2000) ack 1001 <nop,nop,TS val 2010 ecr 1010>
+   +0 %{ assert tcpi_ca_state == TCP_CA_Recovery, tcpi_ca_state }%
+   +0 %{ assert tcpi_snd_cwnd == 7, tcpi_snd_cwnd }%
+
+   +0 < . 1001:1001(0) ack 1 win 257 <TS val 1011 ecr 2000,sack 2001:6001>
+   +0 %{ assert tcpi_ca_state == TCP_CA_Recovery, tcpi_ca_state }%
+   +0 %{ assert tcpi_snd_cwnd == 7, tcpi_snd_cwnd }%