Self tests added for new helper Signed-off-by: Carlos Neira <cneirabustos@xxxxxxxxx> --- tools/testing/selftests/bpf/Makefile | 2 +- tools/testing/selftests/bpf/bpf_helpers.h | 3 + .../selftests/bpf/progs/test_pidns_kern.c | 71 ++++++++ tools/testing/selftests/bpf/test_pidns.c | 152 ++++++++++++++++++ 4 files changed, 227 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/progs/test_pidns_kern.c create mode 100644 tools/testing/selftests/bpf/test_pidns.c diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 7f3196af1ae4..d86b28aa8f44 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -28,7 +28,7 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test test_sock test_btf test_sockmap get_cgroup_id_user test_socket_cookie \ test_cgroup_storage test_select_reuseport test_section_names \ test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \ - test_btf_dump test_cgroup_attach xdping + test_btf_dump test_cgroup_attach xdping test_pidns BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c))) TEST_GEN_FILES = $(BPF_OBJ_FILES) diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h index 6c4930bc6e2e..03d0e15ae29f 100644 --- a/tools/testing/selftests/bpf/bpf_helpers.h +++ b/tools/testing/selftests/bpf/bpf_helpers.h @@ -231,6 +231,9 @@ static int (*bpf_send_signal)(unsigned sig) = (void *)BPF_FUNC_send_signal; static long long (*bpf_tcp_gen_syncookie)(struct bpf_sock *sk, void *ip, int ip_len, void *tcp, int tcp_len) = (void *) BPF_FUNC_tcp_gen_syncookie; +static int (*bpf_get_ns_current_pid_tgid)(__u32 dev, __u64 inum) = + (void *) BPF_FUNC_get_ns_current_pid_tgid; + /* llvm builtin functions that eBPF C program may use to * emit BPF_LD_ABS and BPF_LD_IND instructions diff --git a/tools/testing/selftests/bpf/progs/test_pidns_kern.c b/tools/testing/selftests/bpf/progs/test_pidns_kern.c new file mode 100644 index 000000000000..96cb707db3ee --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_pidns_kern.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2018 Carlos Neira cneirabustos@xxxxxxxxx + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ + +#include <linux/bpf.h> +#include "bpf_helpers.h" + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} ns_inum_map SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u32); +} ns_dev_map SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u32); +} pidmap SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} ns_pid_map SEC(".maps"); + + + +SEC("tracepoint/syscalls/sys_enter_nanosleep") +int trace(void *ctx) +{ + __u32 key = 0, *expected_pid, *dev; + __u64 *val, *inum, nspid; + __u32 pid; + + dev = bpf_map_lookup_elem(&ns_dev_map, &key); + if (!dev) + return 0; + + inum = bpf_map_lookup_elem(&ns_inum_map, &key); + if (!inum) + return 0; + + nspid = bpf_get_ns_current_pid_tgid(*dev, *inum); + expected_pid = bpf_map_lookup_elem(&pidmap, &key); + + if (!expected_pid || *expected_pid != nspid) + return 0; + + val = bpf_map_lookup_elem(&ns_pid_map, &key); + if (val) + *val = nspid; + + return 0; +} + +char _license[] SEC("license") = "GPL"; +__u32 _version SEC("version") = 1; diff --git a/tools/testing/selftests/bpf/test_pidns.c b/tools/testing/selftests/bpf/test_pidns.c new file mode 100644 index 000000000000..088f8025f2bf --- /dev/null +++ b/tools/testing/selftests/bpf/test_pidns.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2018 Carlos Neira cneirabustos@xxxxxxxxx + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <fcntl.h> +#include <syscall.h> +#include <unistd.h> +#include <linux/perf_event.h> +#include <sys/ioctl.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/stat.h> + +#include <linux/bpf.h> +#include <bpf/bpf.h> +#include <bpf/libbpf.h> + +#include "cgroup_helpers.h" +#include "bpf_rlimit.h" + +#define CHECK(condition, tag, format...) ({ \ + int __ret = !!(condition); \ + if (__ret) { \ + printf("%s:FAIL:%s ", __func__, tag); \ + printf(format); \ + } else { \ + printf("%s:PASS:%s\n", __func__, tag); \ + } \ + __ret; \ +}) + +static int bpf_find_map(const char *test, struct bpf_object *obj, + const char *name) +{ + struct bpf_map *map; + + map = bpf_object__find_map_by_name(obj, name); + if (!map) + return -1; + return bpf_map__fd(map); +} + + +int main(int argc, char **argv) +{ + int pidmap_fd, ns_inum_map_fd, ns_dev_map_fd, ns_pid_map_fd; + const char *probe_name = "syscalls/sys_enter_nanosleep"; + const char *file = "test_pidns_kern.o"; + int err, bytes, efd, prog_fd, pmu_fd; + struct perf_event_attr attr = {}; + struct bpf_object *obj; + __u32 nspid = 0; + __u32 key = 0, pid; + int exit_code = 1; + struct stat st; + char buf[256]; + + err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd); + if (CHECK(err, "bpf_prog_load", "err %d errno %d\n", err, errno)) + goto cleanup_cgroup_env; + + ns_dev_map_fd = bpf_find_map(__func__, obj, "ns_dev_map"); + if (CHECK(ns_dev_map_fd < 0, "bpf_find_map", "err %d errno %d\n", + ns_dev_map_fd, errno)) + goto close_prog; + + ns_inum_map_fd = bpf_find_map(__func__, obj, "ns_inum_map"); + if (CHECK(ns_inum_map_fd < 0, "bpf_find_map", "err %d errno %d\n", + ns_inum_map_fd, errno)) + goto close_prog; + + ns_pid_map_fd = bpf_find_map(__func__, obj, "ns_pid_map"); + if (CHECK(ns_pid_map_fd < 0, "bpf_find_map", "err %d errno %d\n", + ns_pid_map_fd, errno)) + goto close_prog; + + pidmap_fd = bpf_find_map(__func__, obj, "pidmap"); + if (CHECK(pidmap_fd < 0, "bpf_find_map", "err %d errno %d\n", + pidmap_fd, errno)) + goto close_prog; + + pid = getpid(); + bpf_map_update_elem(pidmap_fd, &key, &pid, 0); + + if (stat("/proc/self/ns/pid", &st)) + goto close_prog; + + bpf_map_update_elem(ns_inum_map_fd, &key, &st.st_ino, 0); + bpf_map_update_elem(ns_dev_map_fd, &key, &st.st_dev, 0); + + + snprintf(buf, sizeof(buf), + "/sys/kernel/debug/tracing/events/%s/id", probe_name); + efd = open(buf, O_RDONLY, 0); + if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno)) + goto close_prog; + bytes = read(efd, buf, sizeof(buf)); + close(efd); + if (CHECK(bytes <= 0 || bytes >= sizeof(buf), "read", + "bytes %d errno %d\n", bytes, errno)) + goto close_prog; + + attr.config = strtol(buf, NULL, 0); + attr.type = PERF_TYPE_TRACEPOINT; + attr.sample_type = PERF_SAMPLE_RAW; + attr.sample_period = 1; + attr.wakeup_events = 1; + + pmu_fd = syscall(__NR_perf_event_open, &attr, getpid(), -1, -1, 0); + if (CHECK(pmu_fd < 0, "perf_event_open", "err %d errno %d\n", pmu_fd, + errno)) + goto close_prog; + + err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0); + if (CHECK(err, "perf_event_ioc_enable", "err %d errno %d\n", err, + errno)) + goto close_pmu; + + err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); + if (CHECK(err, "perf_event_ioc_set_bpf", "err %d errno %d\n", err, + errno)) + goto close_pmu; + + /* trigger some syscalls */ + sleep(1); + + err = bpf_map_lookup_elem(ns_pid_map_fd, &key, &nspid); + if (CHECK(err, "bpf_map_lookup_elem", "err %d errno %d\n", err, errno)) + goto close_pmu; + + if (CHECK(nspid != pid, "compare nspid vs pid", + "kern nspid %u user pid %u", nspid, pid)) + goto close_pmu; + + exit_code = 0; + printf("%s:PASS\n", argv[0]); + +close_pmu: + close(pmu_fd); +close_prog: + bpf_object__close(obj); +cleanup_cgroup_env: + return exit_code; +} -- 2.20.1