Use IP_LOCAL_PORT_RANGE to limit a socket to 8 ports and bind 8 SO_REUSEPORT sockets to port 0. They must get 8 distinct ports and the 9th bind must fail with EADDRINUSE. TCP and UDP should both behave this way.
# ./ip_local_port_range.sh Before the udp fix: ok 5 ip_local_port_range.ip4_tcp.exhaust_8_port_range_reuseport not ok 12 ip_local_port_range.ip4_udp.exhaust_8_port_range_reuseport ok 33 ip_local_port_range.ip6_tcp.exhaust_8_port_range_reuseport not ok 40 ip_local_port_range.ip6_udp.exhaust_8_port_range_reuseport After: ok 5 ip_local_port_range.ip4_tcp.exhaust_8_port_range_reuseport ok 12 ip_local_port_range.ip4_udp.exhaust_8_port_range_reuseport ok 33 ip_local_port_range.ip6_tcp.exhaust_8_port_range_reuseport ok 40 ip_local_port_range.ip6_udp.exhaust_8_port_range_reuseport Signed-off-by: Jiayuan Chen <[email protected]> --- .../selftests/net/ip_local_port_range.c | 27 ++++++++++++++++++- 1 file changed, 26 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..04feb702fff4 100644 --- a/tools/testing/selftests/net/ip_local_port_range.c +++ b/tools/testing/selftests/net/ip_local_port_range.c @@ -301,7 +301,9 @@ TEST_F(ip_local_port_range, single_port_range) } } -TEST_F(ip_local_port_range, exhaust_8_port_range) +static void exhaust_8_port_range(struct __test_metadata *_metadata, + const FIXTURE_VARIANT(ip_local_port_range) *variant, + bool reuseport) { __u8 port_set = 0; int i, fd, err; @@ -313,6 +315,11 @@ 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"); + if (reuseport) { + err = setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &(int){ 1 }, sizeof(int)); + ASSERT_TRUE(!err) TH_LOG("setsockopt(SO_REUSEPORT) 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 +342,11 @@ 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"); + if (reuseport) { + err = setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &(int){ 1 }, sizeof(int)); + ASSERT_TRUE(!err) TH_LOG("setsockopt(SO_REUSEPORT) 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 +364,19 @@ 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, false); +} + +/* Auto-selected port must not land on a port already taken by a + * SO_REUSEPORT socket, 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, true); +} + TEST_F(ip_local_port_range, late_bind) { union { -- 2.43.0
