From a96d1cfb2da040bdf692d22022371b249742abb2 Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Fri, 1 Sep 2023 16:11:29 -0700 Subject: [PATCH] selftests/bpf: Check bpf_sk_storage has uncharged sk_omem_alloc This patch checks the sk_omem_alloc has been uncharged by bpf_sk_storage during the __sk_destruct. Signed-off-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20230901231129.578493-4-martin.lau@linux.dev --- .../bpf/prog_tests/sk_storage_omem_uncharge.c | 56 ++++++++++++++++++++ .../testing/selftests/bpf/progs/bpf_tracing_net.h | 1 + .../selftests/bpf/progs/sk_storage_omem_uncharge.c | 61 ++++++++++++++++++++++ 3 files changed, 118 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/sk_storage_omem_uncharge.c create mode 100644 tools/testing/selftests/bpf/progs/sk_storage_omem_uncharge.c diff --git a/tools/testing/selftests/bpf/prog_tests/sk_storage_omem_uncharge.c b/tools/testing/selftests/bpf/prog_tests/sk_storage_omem_uncharge.c new file mode 100644 index 0000000..f35852d --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/sk_storage_omem_uncharge.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Facebook */ +#include +#include +#include +#include +#include "sk_storage_omem_uncharge.skel.h" + +void test_sk_storage_omem_uncharge(void) +{ + struct sk_storage_omem_uncharge *skel; + int sk_fd = -1, map_fd, err, value; + socklen_t optlen; + + skel = sk_storage_omem_uncharge__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel open_and_load")) + return; + map_fd = bpf_map__fd(skel->maps.sk_storage); + + /* A standalone socket not binding to addr:port, + * so nentns is not needed. + */ + sk_fd = socket(AF_INET6, SOCK_STREAM, 0); + if (!ASSERT_GE(sk_fd, 0, "socket")) + goto done; + + optlen = sizeof(skel->bss->cookie); + err = getsockopt(sk_fd, SOL_SOCKET, SO_COOKIE, &skel->bss->cookie, &optlen); + if (!ASSERT_OK(err, "getsockopt(SO_COOKIE)")) + goto done; + + value = 0; + err = bpf_map_update_elem(map_fd, &sk_fd, &value, 0); + if (!ASSERT_OK(err, "bpf_map_update_elem(value=0)")) + goto done; + + value = 0xdeadbeef; + err = bpf_map_update_elem(map_fd, &sk_fd, &value, 0); + if (!ASSERT_OK(err, "bpf_map_update_elem(value=0xdeadbeef)")) + goto done; + + err = sk_storage_omem_uncharge__attach(skel); + if (!ASSERT_OK(err, "attach")) + goto done; + + close(sk_fd); + sk_fd = -1; + + ASSERT_EQ(skel->bss->cookie_found, 2, "cookie_found"); + ASSERT_EQ(skel->bss->omem, 0, "omem"); + +done: + sk_storage_omem_uncharge__destroy(skel); + if (sk_fd != -1) + close(sk_fd); +} diff --git a/tools/testing/selftests/bpf/progs/bpf_tracing_net.h b/tools/testing/selftests/bpf/progs/bpf_tracing_net.h index cfed4df..0b793a1 100644 --- a/tools/testing/selftests/bpf/progs/bpf_tracing_net.h +++ b/tools/testing/selftests/bpf/progs/bpf_tracing_net.h @@ -88,6 +88,7 @@ #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr #define sk_flags __sk_common.skc_flags #define sk_reuse __sk_common.skc_reuse +#define sk_cookie __sk_common.skc_cookie #define s6_addr32 in6_u.u6_addr32 diff --git a/tools/testing/selftests/bpf/progs/sk_storage_omem_uncharge.c b/tools/testing/selftests/bpf/progs/sk_storage_omem_uncharge.c new file mode 100644 index 0000000..3e74579 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/sk_storage_omem_uncharge.c @@ -0,0 +1,61 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Facebook */ +#include "vmlinux.h" +#include "bpf_tracing_net.h" +#include +#include +#include + +void *local_storage_ptr = NULL; +void *sk_ptr = NULL; +int cookie_found = 0; +__u64 cookie = 0; +__u32 omem = 0; + +void *bpf_rdonly_cast(void *, __u32) __ksym; + +struct { + __uint(type, BPF_MAP_TYPE_SK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, int); +} sk_storage SEC(".maps"); + +SEC("fexit/bpf_local_storage_destroy") +int BPF_PROG(bpf_local_storage_destroy, struct bpf_local_storage *local_storage) +{ + struct sock *sk; + + if (local_storage_ptr != local_storage) + return 0; + + sk = bpf_rdonly_cast(sk_ptr, bpf_core_type_id_kernel(struct sock)); + if (sk->sk_cookie.counter != cookie) + return 0; + + cookie_found++; + omem = sk->sk_omem_alloc.counter; + local_storage_ptr = NULL; + + return 0; +} + +SEC("fentry/inet6_sock_destruct") +int BPF_PROG(inet6_sock_destruct, struct sock *sk) +{ + int *value; + + if (!cookie || sk->sk_cookie.counter != cookie) + return 0; + + value = bpf_sk_storage_get(&sk_storage, sk, 0, 0); + if (value && *value == 0xdeadbeef) { + cookie_found++; + sk_ptr = sk; + local_storage_ptr = sk->sk_bpf_storage; + } + + return 0; +} + +char _license[] SEC("license") = "GPL"; -- 2.7.4