From d9ba9934285514f1f95d96326a82398a22dc77f2 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Sat, 11 Mar 2023 19:19:03 -0800 Subject: [PATCH 1/2] tcp: Fix bind() conflict check for dual-stack wildcard address. Paul Holzinger reported [0] that commit 5456262d2baa ("net: Fix incorrect address comparison when searching for a bind2 bucket") introduced a bind() regression. Paul also gave a nice repro that calls two types of bind() on the same port, both of which now succeed, but the second call should fail: bind(fd1, ::, port) + bind(fd2, 127.0.0.1, port) The cited commit added address family tests in three functions to fix the uninit-value KMSAN report. [1] However, the test added to inet_bind2_bucket_match_addr_any() removed a necessary conflict check; the dual-stack wildcard address no longer conflicts with an IPv4 non-wildcard address. If tb->family is AF_INET6 and sk->sk_family is AF_INET in inet_bind2_bucket_match_addr_any(), we still need to check if tb has the dual-stack wildcard address. Note that the IPv4 wildcard address does not conflict with IPv6 non-wildcard addresses. [0]: https://lore.kernel.org/netdev/e21bf153-80b0-9ec0-15ba-e04a4ad42c34@redhat.com/ [1]: https://lore.kernel.org/netdev/CAG_fn=Ud3zSW7AZWXc+asfMhZVL5ETnvuY44Pmyv4NPv-ijN-A@mail.gmail.com/ Fixes: 5456262d2baa ("net: Fix incorrect address comparison when searching for a bind2 bucket") Signed-off-by: Kuniyuki Iwashima Reported-by: Paul Holzinger Link: https://lore.kernel.org/netdev/CAG_fn=Ud3zSW7AZWXc+asfMhZVL5ETnvuY44Pmyv4NPv-ijN-A@mail.gmail.com/ Reviewed-by: Eric Dumazet Tested-by: Paul Holzinger Reviewed-by: Martin KaFai Lau Signed-off-by: Jakub Kicinski --- net/ipv4/inet_hashtables.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index e41fdc38ce19..6edae3886885 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -828,8 +828,14 @@ bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const #if IS_ENABLED(CONFIG_IPV6) struct in6_addr addr_any = {}; - if (sk->sk_family != tb->family) + if (sk->sk_family != tb->family) { + if (sk->sk_family == AF_INET) + return net_eq(ib2_net(tb), net) && tb->port == port && + tb->l3mdev == l3mdev && + ipv6_addr_equal(&tb->v6_rcv_saddr, &addr_any); + return false; + } if (sk->sk_family == AF_INET6) return net_eq(ib2_net(tb), net) && tb->port == port && From 13715acf8ab5b32a6d7e42686fceeb66df114185 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Sat, 11 Mar 2023 19:19:04 -0800 Subject: [PATCH 2/2] selftest: Add test for bind() conflicts. The test checks if (IPv4, IPv6) address pair properly conflict or not. * IPv4 * 0.0.0.0 * 127.0.0.1 * IPv6 * :: * ::1 If the IPv6 address is [::], the second bind() always fails. Signed-off-by: Kuniyuki Iwashima Signed-off-by: Jakub Kicinski --- tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/Makefile | 1 + tools/testing/selftests/net/bind_wildcard.c | 114 ++++++++++++++++++++ 3 files changed, 116 insertions(+) create mode 100644 tools/testing/selftests/net/bind_wildcard.c diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore index a6911cae368c..80f06aa62034 100644 --- a/tools/testing/selftests/net/.gitignore +++ b/tools/testing/selftests/net/.gitignore @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only bind_bhash bind_timewait +bind_wildcard csum cmsg_sender diag_uid diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index 6cd8993454d7..80fbfe0330f6 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -80,6 +80,7 @@ TEST_GEN_FILES += sctp_hello TEST_GEN_FILES += csum TEST_GEN_FILES += nat6to4.o TEST_GEN_FILES += ip_local_port_range +TEST_GEN_FILES += bind_wildcard TEST_FILES := settings diff --git a/tools/testing/selftests/net/bind_wildcard.c b/tools/testing/selftests/net/bind_wildcard.c new file mode 100644 index 000000000000..58edfc15d28b --- /dev/null +++ b/tools/testing/selftests/net/bind_wildcard.c @@ -0,0 +1,114 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright Amazon.com Inc. or its affiliates. */ + +#include +#include + +#include "../kselftest_harness.h" + +FIXTURE(bind_wildcard) +{ + struct sockaddr_in addr4; + struct sockaddr_in6 addr6; + int expected_errno; +}; + +FIXTURE_VARIANT(bind_wildcard) +{ + const __u32 addr4_const; + const struct in6_addr *addr6_const; +}; + +FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_any) +{ + .addr4_const = INADDR_ANY, + .addr6_const = &in6addr_any, +}; + +FIXTURE_VARIANT_ADD(bind_wildcard, v4_any_v6_local) +{ + .addr4_const = INADDR_ANY, + .addr6_const = &in6addr_loopback, +}; + +FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_any) +{ + .addr4_const = INADDR_LOOPBACK, + .addr6_const = &in6addr_any, +}; + +FIXTURE_VARIANT_ADD(bind_wildcard, v4_local_v6_local) +{ + .addr4_const = INADDR_LOOPBACK, + .addr6_const = &in6addr_loopback, +}; + +FIXTURE_SETUP(bind_wildcard) +{ + self->addr4.sin_family = AF_INET; + self->addr4.sin_port = htons(0); + self->addr4.sin_addr.s_addr = htonl(variant->addr4_const); + + self->addr6.sin6_family = AF_INET6; + self->addr6.sin6_port = htons(0); + self->addr6.sin6_addr = *variant->addr6_const; + + if (variant->addr6_const == &in6addr_any) + self->expected_errno = EADDRINUSE; + else + self->expected_errno = 0; +} + +FIXTURE_TEARDOWN(bind_wildcard) +{ +} + +void bind_sockets(struct __test_metadata *_metadata, + FIXTURE_DATA(bind_wildcard) *self, + struct sockaddr *addr1, socklen_t addrlen1, + struct sockaddr *addr2, socklen_t addrlen2) +{ + int fd[2]; + int ret; + + fd[0] = socket(addr1->sa_family, SOCK_STREAM, 0); + ASSERT_GT(fd[0], 0); + + ret = bind(fd[0], addr1, addrlen1); + ASSERT_EQ(ret, 0); + + ret = getsockname(fd[0], addr1, &addrlen1); + ASSERT_EQ(ret, 0); + + ((struct sockaddr_in *)addr2)->sin_port = ((struct sockaddr_in *)addr1)->sin_port; + + fd[1] = socket(addr2->sa_family, SOCK_STREAM, 0); + ASSERT_GT(fd[1], 0); + + ret = bind(fd[1], addr2, addrlen2); + if (self->expected_errno) { + ASSERT_EQ(ret, -1); + ASSERT_EQ(errno, self->expected_errno); + } else { + ASSERT_EQ(ret, 0); + } + + close(fd[1]); + close(fd[0]); +} + +TEST_F(bind_wildcard, v4_v6) +{ + bind_sockets(_metadata, self, + (struct sockaddr *)&self->addr4, sizeof(self->addr6), + (struct sockaddr *)&self->addr6, sizeof(self->addr6)); +} + +TEST_F(bind_wildcard, v6_v4) +{ + bind_sockets(_metadata, self, + (struct sockaddr *)&self->addr6, sizeof(self->addr6), + (struct sockaddr *)&self->addr4, sizeof(self->addr4)); +} + +TEST_HARNESS_MAIN