From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-238.mta1.migadu.com [95.215.58.238]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5F02036F90C for ; Mon, 28 Sep 2026 02:36:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.238 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790562969; cv=none; b=G7hPOqUY1Tgy5e/xxL9JOaUhlip9IEvFX+11CsZ1tiTnHI2hvT+Q7jHCEL2rlgce1O6Vw8LTt7Jx87SaFz8MTLAQEJrgNW1mzV9pHdmAcUXDEHp0+Oywb1GdgtzbBimgIOHyPadDiX9z9vLr1UJ8gAgCQDwyuVM5aehlnc7JARE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790562969; c=relaxed/simple; bh=OUtN1NPk1mRcfZkghFoTTbHusGeyv7h9M8UBOmmvCtc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=k8b386+wck2hNq5xvyyfbyBizbs9jJSjsg+5W19CAQp1S2VpMl0beSKLaVLS22swsszKa3BHx+kPJ0Cysg+J1A1hjD3BnfptXHWUrfYESKmOFaX1eG63ZU32hXpV9uUL7EOcTQZzNmKObUTic5BCT3wWp6FTS+1zU3GLfCT+nBM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=ExIenBAr; arc=none smtp.client-ip=95.215.58.238 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="ExIenBAr" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=OUtN1NPk1mRcfZkghFoTTbHusGeyv7h9M8UBOmmvCtc=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1790562964; v=1; x=1791167764; b=ExIenBArV7FedfoeAA9QxeR4kIbQmTaySFLtdu8yio8xOiYmZ8QAsN71JpQ7saBgfEcZjTsR PAX6x7qyfBTe5JcXlM1QWboqGU5Vzivon4lPuWUSfpKyBg7+3T3GZ3/oPlzBQiSaGzujPDSklR8 RvQm/Uc5V6uOwnK/PzOQar3M= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 9cace0c6bcb29ea3; Mon, 28 Sep 2026 02:36:04 +0000 X-Mizu-Trace-ID: 9cace0c6bcb29ea3 X-Migadu-Flow: FLOW_OUT From: Jiayuan Chen To: netdev@vger.kernel.org Cc: Jiayuan Chen , Willem de Bruijn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Shuah Khan , Tom Herbert , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH net-next v2 2/2] selftests/net: check auto-selected port with reuse options Date: Mon, 28 Sep 2026 10:31:42 +0800 Message-ID: <20260928023145.301855-2-jiayuan.chen@linux.dev> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260928023145.301855-1-jiayuan.chen@linux.dev> References: <20260928023145.301855-1-jiayuan.chen@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Use IP_LOCAL_PORT_RANGE to limit a socket to 8 ports, bind 8 sockets to port 0 and check they get 8 distinct ports and the 9th bind fails with EADDRINUSE. Run it for the four combinations of reuse options on the sockets: none (existing test) SO_REUSEPORT SO_REUSEADDR SO_REUSEADDR + SO_REUSEPORT TCP passes all four. Before the udp fix UDP only passes the first one: the scan hands out a port already taken by a socket with the same reuse options, so fewer than 8 distinct ports come back and the 9th bind succeeds. # ./ip_local_port_range.sh Before: ok 13 ip_local_port_range.ip4_udp.exhaust_8_port_range not ok 14 ip_local_port_range.ip4_udp.exhaust_8_port_range_reuseport not ok 15 ip_local_port_range.ip4_udp.exhaust_8_port_range_reuseaddr not ok 16 ip_local_port_range.ip4_udp.exhaust_8_port_range_reuseaddr_reuseport ok 49 ip_local_port_range.ip6_udp.exhaust_8_port_range not ok 50 ip_local_port_range.ip6_udp.exhaust_8_port_range_reuseport not ok 51 ip_local_port_range.ip6_udp.exhaust_8_port_range_reuseaddr not ok 52 ip_local_port_range.ip6_udp.exhaust_8_port_range_reuseaddr_reuseport After: ok 13 ip_local_port_range.ip4_udp.exhaust_8_port_range ok 14 ip_local_port_range.ip4_udp.exhaust_8_port_range_reuseport ok 15 ip_local_port_range.ip4_udp.exhaust_8_port_range_reuseaddr ok 16 ip_local_port_range.ip4_udp.exhaust_8_port_range_reuseaddr_reuseport ok 49 ip_local_port_range.ip6_udp.exhaust_8_port_range ok 50 ip_local_port_range.ip6_udp.exhaust_8_port_range_reuseport ok 51 ip_local_port_range.ip6_udp.exhaust_8_port_range_reuseaddr ok 52 ip_local_port_range.ip6_udp.exhaust_8_port_range_reuseaddr_reuseport Signed-off-by: Jiayuan Chen --- .../selftests/net/ip_local_port_range.c | 52 ++++++++++++++++++- 1 file changed, 51 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/ip_local_port_range.c b/tools/testing/selftests/net/ip_local_port_range.c index e6834a6cfc8f..3d32b33cba46 100644 --- a/tools/testing/selftests/net/ip_local_port_range.c +++ b/tools/testing/selftests/net/ip_local_port_range.c @@ -301,7 +301,27 @@ TEST_F(ip_local_port_range, single_port_range) } } -TEST_F(ip_local_port_range, exhaust_8_port_range) +#define REUSEADDR 0x1 +#define REUSEPORT 0x2 + +static int set_reuse_opts(int fd, unsigned int flags) +{ + int one = 1; + + if ((flags & REUSEADDR) && + setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) + return -1; + + if ((flags & REUSEPORT) && + setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one))) + return -1; + + return 0; +} + +static void exhaust_8_port_range(struct __test_metadata *_metadata, + const FIXTURE_VARIANT(ip_local_port_range) *variant, + unsigned int flags) { __u8 port_set = 0; int i, fd, err; @@ -313,6 +333,9 @@ TEST_F(ip_local_port_range, exhaust_8_port_range) fd = socket(variant->so_domain, variant->so_type, variant->so_protocol); ASSERT_GE(fd, 0) TH_LOG("socket failed"); + err = set_reuse_opts(fd, flags); + ASSERT_TRUE(!err) TH_LOG("setsockopt(SO_REUSE*) failed"); + range = pack_port_range(40000, 40007); err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range)); ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_LOCAL_PORT_RANGE) failed"); @@ -335,6 +358,9 @@ TEST_F(ip_local_port_range, exhaust_8_port_range) fd = socket(variant->so_domain, variant->so_type, variant->so_protocol); ASSERT_GE(fd, 0) TH_LOG("socket failed"); + err = set_reuse_opts(fd, flags); + ASSERT_TRUE(!err) TH_LOG("setsockopt(SO_REUSE*) failed"); + range = pack_port_range(40000, 40007); err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range)); ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_LOCAL_PORT_RANGE) failed"); @@ -352,6 +378,30 @@ TEST_F(ip_local_port_range, exhaust_8_port_range) } } +TEST_F(ip_local_port_range, exhaust_8_port_range) +{ + exhaust_8_port_range(_metadata, variant, 0); +} + +/* Auto-selected port must not land on a port already taken by another + * socket, whatever reuse options both of them have, so all 8 sockets + * must get distinct ports. + */ +TEST_F(ip_local_port_range, exhaust_8_port_range_reuseport) +{ + exhaust_8_port_range(_metadata, variant, REUSEPORT); +} + +TEST_F(ip_local_port_range, exhaust_8_port_range_reuseaddr) +{ + exhaust_8_port_range(_metadata, variant, REUSEADDR); +} + +TEST_F(ip_local_port_range, exhaust_8_port_range_reuseaddr_reuseport) +{ + exhaust_8_port_range(_metadata, variant, REUSEADDR | REUSEPORT); +} + TEST_F(ip_local_port_range, late_bind) { union { -- 2.43.0