From d1ba1204f2eec134937cb32997ee47756d448aa2 Mon Sep 17 00:00:00 2001 From: Jakub Sitnicki Date: Mon, 17 Feb 2020 12:15:30 +0000 Subject: [PATCH] selftests/bpf: Test unhashing kTLS socket after removing from map When a TCP socket gets inserted into a sockmap, its sk_prot callbacks get replaced with tcp_bpf callbacks built from regular tcp callbacks. If TLS gets enabled on the same socket, sk_prot callbacks get replaced once again, this time with kTLS callbacks built from tcp_bpf callbacks. Now, we allow removing a socket from a sockmap that has kTLS enabled. After removal, socket remains with kTLS configured. This is where things things get tricky. Since the socket has a set of sk_prot callbacks that are a mix of kTLS and tcp_bpf callbacks, we need to restore just the tcp_bpf callbacks to the original ones. At the moment, it comes down to the the unhash operation. We had a regression recently because tcp_bpf callbacks were not cleared in this particular scenario of removing a kTLS socket from a sockmap. It got fixed in commit 4da6a196f93b ("bpf: Sockmap/tls, during free we may call tcp_bpf_unhash() in loop"). Add a test that triggers the regression so that we don't reintroduce it in the future. Signed-off-by: Jakub Sitnicki Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20200217121530.754315-4-jakub@cloudflare.com --- .../selftests/bpf/prog_tests/sockmap_ktls.c | 123 +++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/sockmap_ktls.c diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_ktls.c b/tools/testing/selftests/bpf/prog_tests/sockmap_ktls.c new file mode 100644 index 0000000..589b50c --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_ktls.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2020 Cloudflare +/* + * Tests for sockmap/sockhash holding kTLS sockets. + */ + +#include "test_progs.h" + +#define MAX_TEST_NAME 80 + +static int tcp_server(int family) +{ + int err, s; + + s = socket(family, SOCK_STREAM, 0); + if (CHECK_FAIL(s == -1)) { + perror("socket"); + return -1; + } + + err = listen(s, SOMAXCONN); + if (CHECK_FAIL(err)) { + perror("listen"); + return -1; + } + + return s; +} + +static int disconnect(int fd) +{ + struct sockaddr unspec = { AF_UNSPEC }; + + return connect(fd, &unspec, sizeof(unspec)); +} + +/* Disconnect (unhash) a kTLS socket after removing it from sockmap. */ +static void test_sockmap_ktls_disconnect_after_delete(int family, int map) +{ + struct sockaddr_storage addr = {0}; + socklen_t len = sizeof(addr); + int err, cli, srv, zero = 0; + + srv = tcp_server(family); + if (srv == -1) + return; + + err = getsockname(srv, (struct sockaddr *)&addr, &len); + if (CHECK_FAIL(err)) { + perror("getsockopt"); + goto close_srv; + } + + cli = socket(family, SOCK_STREAM, 0); + if (CHECK_FAIL(cli == -1)) { + perror("socket"); + goto close_srv; + } + + err = connect(cli, (struct sockaddr *)&addr, len); + if (CHECK_FAIL(err)) { + perror("connect"); + goto close_cli; + } + + err = bpf_map_update_elem(map, &zero, &cli, 0); + if (CHECK_FAIL(err)) { + perror("bpf_map_update_elem"); + goto close_cli; + } + + err = setsockopt(cli, IPPROTO_TCP, TCP_ULP, "tls", strlen("tls")); + if (CHECK_FAIL(err)) { + perror("setsockopt(TCP_ULP)"); + goto close_cli; + } + + err = bpf_map_delete_elem(map, &zero); + if (CHECK_FAIL(err)) { + perror("bpf_map_delete_elem"); + goto close_cli; + } + + err = disconnect(cli); + if (CHECK_FAIL(err)) + perror("disconnect"); + +close_cli: + close(cli); +close_srv: + close(srv); +} + +static void run_tests(int family, enum bpf_map_type map_type) +{ + char test_name[MAX_TEST_NAME]; + int map; + + map = bpf_create_map(map_type, sizeof(int), sizeof(int), 1, 0); + if (CHECK_FAIL(map == -1)) { + perror("bpf_map_create"); + return; + } + + snprintf(test_name, MAX_TEST_NAME, + "sockmap_ktls disconnect_after_delete %s %s", + family == AF_INET ? "IPv4" : "IPv6", + map_type == BPF_MAP_TYPE_SOCKMAP ? "SOCKMAP" : "SOCKHASH"); + if (!test__start_subtest(test_name)) + return; + + test_sockmap_ktls_disconnect_after_delete(family, map); + + close(map); +} + +void test_sockmap_ktls(void) +{ + run_tests(AF_INET, BPF_MAP_TYPE_SOCKMAP); + run_tests(AF_INET, BPF_MAP_TYPE_SOCKHASH); + run_tests(AF_INET6, BPF_MAP_TYPE_SOCKMAP); + run_tests(AF_INET6, BPF_MAP_TYPE_SOCKHASH); +} -- 2.7.4