Merge branch 'mptcp-various-small-improvements'

Matthieu Baerts says:

====================
mptcp: various small improvements

This series brings various small improvements to MPTCP and its
selftests:

Patch 1 prints an error if there are duplicated subtests names. It is
important to have unique (sub)tests names in TAP, because some CI
environments drop (sub)tests with duplicated names.

Patch 2 is a preparation for patches 3 and 4, which check the protocol
in tcp_sk() and mptcp_sk() with DEBUG_NET, only in code from net/mptcp/.
We recently had the case where an MPTCP socket was wrongly treated as a
TCP one, and fuzzers and static checkers never spot the issue. This
would prevent such issues in the future.

Patches 5 to 7 are some cleanup for the MPTCP selftests. These patches
are not supposed to change the behaviour.

Patch 8 sets the poll timeout in diag selftest to the same value as the
one used in the other selftests.
====================

Link: https://lore.kernel.org/r/20240223-upstream-net-next-20240223-misc-improvements-v1-0-b6c8a10396bd@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

7 files changed, 61 insertions, 14 deletions

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index f89b197a9f92..051b100d9403 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -348,7 +348,23 @@ static inline void msk_owned_by_me(const struct mptcp_sock *msk)
 	sock_owned_by_me((const struct sock *)msk);
 }
 
+#ifdef CONFIG_DEBUG_NET
+/* MPTCP-specific: we might (indirectly) call this helper with the wrong sk */
+#undef tcp_sk
+#define tcp_sk(ptr) ({								\
+	typeof(ptr) _ptr = (ptr);						\
+	WARN_ON(_ptr->sk_protocol != IPPROTO_TCP);				\
+	container_of_const(_ptr, struct tcp_sock, inet_conn.icsk_inet.sk);	\
+})
+#define mptcp_sk(ptr) ({						\
+	typeof(ptr) _ptr = (ptr);					\
+	WARN_ON(_ptr->sk_protocol != IPPROTO_MPTCP);			\
+	container_of_const(_ptr, struct mptcp_sock, sk.icsk_inet.sk);	\
+})
+
+#else /* !CONFIG_DEBUG_NET */
 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk)
+#endif
 
 /* the msk socket don't use the backlog, also account for the bulk
  * free memory
diff --git a/net/mptcp/token_test.c b/net/mptcp/token_test.c
index bfff53e668da..4fc39fa2e262 100644
--- a/net/mptcp/token_test.c
+++ b/net/mptcp/token_test.c
@@ -52,14 +52,19 @@ static struct mptcp_subflow_context *build_ctx(struct kunit *test)
 static struct mptcp_sock *build_msk(struct kunit *test)
 {
 	struct mptcp_sock *msk;
+	struct sock *sk;
 
 	msk = kunit_kzalloc(test, sizeof(struct mptcp_sock), GFP_USER);
 	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, msk);
 	refcount_set(&((struct sock *)msk)->sk_refcnt, 1);
 	sock_net_set((struct sock *)msk, &init_net);
 
+	sk = (struct sock *)msk;
+
 	/* be sure the token helpers can dereference sk->sk_prot */
-	((struct sock *)msk)->sk_prot = &tcp_prot;
+	sk->sk_prot = &tcp_prot;
+	sk->sk_protocol = IPPROTO_MPTCP;
+
 	return msk;
 }
 
diff --git a/tools/testing/selftests/net/mptcp/diag.sh b/tools/testing/selftests/net/mptcp/diag.sh
index 0a58ebb8b04c..8573326d326a 100755
--- a/tools/testing/selftests/net/mptcp/diag.sh
+++ b/tools/testing/selftests/net/mptcp/diag.sh
@@ -8,7 +8,7 @@ rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
 ns="ns1-$rndh"
 ksft_skip=4
 test_cnt=1
-timeout_poll=100
+timeout_poll=30
 timeout_test=$((timeout_poll * 2 + 1))
 ret=0
 
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index c07386e21e0a..3f198743cb03 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -29,11 +29,11 @@ iptables="iptables"
 ip6tables="ip6tables"
 timeout_poll=30
 timeout_test=$((timeout_poll * 2 + 1))
-capture=0
-checksum=0
+capture=false
+checksum=false
 ip_mptcp=0
 check_invert=0
-validate_checksum=0
+validate_checksum=false
 init=0
 evts_ns1=""
 evts_ns2=""
@@ -100,7 +100,7 @@ init_partial()
 		ip netns exec $netns sysctl -q net.mptcp.pm_type=0 2>/dev/null || true
 		ip netns exec $netns sysctl -q net.ipv4.conf.all.rp_filter=0
 		ip netns exec $netns sysctl -q net.ipv4.conf.default.rp_filter=0
-		if [ $checksum -eq 1 ]; then
+		if $checksum; then
 			ip netns exec $netns sysctl -q net.mptcp.checksum_enabled=1
 		fi
 	done
@@ -380,7 +380,7 @@ reset_with_checksum()
 	ip netns exec $ns1 sysctl -q net.mptcp.checksum_enabled=$ns1_enable
 	ip netns exec $ns2 sysctl -q net.mptcp.checksum_enabled=$ns2_enable
 
-	validate_checksum=1
+	validate_checksum=true
 }
 
 reset_with_allow_join_id0()
@@ -413,7 +413,7 @@ reset_with_allow_join_id0()
 setup_fail_rules()
 {
 	check_invert=1
-	validate_checksum=1
+	validate_checksum=true
 	local i="$1"
 	local ip="${2:-4}"
 	local tables
@@ -1017,7 +1017,7 @@ do_transfer()
 	:> "$sout"
 	:> "$capout"
 
-	if [ $capture -eq 1 ]; then
+	if $capture; then
 		local capuser
 		if [ -z $SUDO_USER ] ; then
 			capuser=""
@@ -1119,7 +1119,7 @@ do_transfer()
 	wait $spid
 	local rets=$?
 
-	if [ $capture -eq 1 ]; then
+	if $capture; then
 	    sleep 1
 	    kill $cappid
 	fi
@@ -1507,7 +1507,7 @@ chk_join_nr()
 	else
 		print_ok
 	fi
-	if [ $validate_checksum -eq 1 ]; then
+	if $validate_checksum; then
 		chk_csum_nr $csum_ns1 $csum_ns2
 		chk_fail_nr $fail_nr $fail_nr
 		chk_rst_nr $rst_nr $rst_nr
@@ -3664,10 +3664,10 @@ while getopts "${all_tests_args}cCih" opt; do
 			tests+=("${all_tests[${opt}]}")
 			;;
 		c)
-			capture=1
+			capture=true
 			;;
 		C)
-			checksum=1
+			checksum=true
 			;;
 		i)
 			ip_mptcp=1
diff --git a/tools/testing/selftests/net/mptcp/mptcp_lib.sh b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
index 3a2abae5993e..037cb3e84330 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_lib.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
@@ -9,6 +9,7 @@ readonly KSFT_SKIP=4
 readonly KSFT_TEST="${MPTCP_LIB_KSFT_TEST:-$(basename "${0}" .sh)}"
 
 MPTCP_LIB_SUBTESTS=()
+MPTCP_LIB_SUBTESTS_DUPLICATED=0
 
 # only if supported (or forced) and not disabled, see no-color.org
 if { [ -t 1 ] || [ "${SELFTESTS_MPTCP_LIB_COLOR_FORCE:-}" = "1" ]; } &&
@@ -146,12 +147,26 @@ mptcp_lib_kversion_ge() {
 	mptcp_lib_fail_if_expected_feature "kernel version ${1} lower than ${v}"
 }
 
+__mptcp_lib_result_check_duplicated() {
+	local subtest
+
+	for subtest in "${MPTCP_LIB_SUBTESTS[@]}"; do
+		if [[ "${subtest}" == *" - ${KSFT_TEST}: ${*%% #*}" ]]; then
+			MPTCP_LIB_SUBTESTS_DUPLICATED=1
+			mptcp_lib_print_err "Duplicated entry: ${*}"
+			break
+		fi
+	done
+}
+
 __mptcp_lib_result_add() {
 	local result="${1}"
 	shift
 
 	local id=$((${#MPTCP_LIB_SUBTESTS[@]} + 1))
 
+	__mptcp_lib_result_check_duplicated "${*}"
+
 	MPTCP_LIB_SUBTESTS+=("${result} ${id} - ${KSFT_TEST}: ${*}")
 }
 
@@ -206,6 +221,12 @@ mptcp_lib_result_print_all_tap() {
 	for subtest in "${MPTCP_LIB_SUBTESTS[@]}"; do
 		printf "%s\n" "${subtest}"
 	done
+
+	if [ "${MPTCP_LIB_SUBTESTS_DUPLICATED}" = 1 ] &&
+	   mptcp_lib_expect_all_features; then
+		mptcp_lib_print_err "Duplicated test entries"
+		exit ${KSFT_FAIL}
+	fi
 }
 
 # get the value of keyword $1 in the line marked by keyword $2
diff --git a/tools/testing/selftests/net/mptcp/pm_netlink.sh b/tools/testing/selftests/net/mptcp/pm_netlink.sh
index 71899a3ffa7a..ebfefae71e13 100755
--- a/tools/testing/selftests/net/mptcp/pm_netlink.sh
+++ b/tools/testing/selftests/net/mptcp/pm_netlink.sh
@@ -28,7 +28,6 @@ sec=$(date +%s)
 rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
 ns1="ns1-$rndh"
 err=$(mktemp)
-ret=0
 
 cleanup()
 {
diff --git a/tools/testing/selftests/net/mptcp/simult_flows.sh b/tools/testing/selftests/net/mptcp/simult_flows.sh
index 8f9ddb3ad4fe..ed0165c15a24 100755
--- a/tools/testing/selftests/net/mptcp/simult_flows.sh
+++ b/tools/testing/selftests/net/mptcp/simult_flows.sh
@@ -16,6 +16,12 @@ test_cnt=1
 ret=0
 bail=0
 slack=50
+large=""
+small=""
+sout=""
+cout=""
+capout=""
+size=0
 
 usage() {
 	echo "Usage: $0 [ -b ] [ -c ] [ -d ]"