tools/testing/selftests/bpf: Add self-tests for new helper bpf_get_ns_current_pid_tgid. (1c1052e0) · Commits · 戴 / test

tools/testing/selftests/bpf/.gitignore

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		@@ -31,6 +31,7 @@ test_tcp_check_syncookie_user
		test_sysctl
		test_hashmap
		test_btf_dump
		test_current_pid_tgid_new_ns
		xdping
		test_cpp
		*.skel.h

tools/testing/selftests/bpf/Makefile

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		@@ -32,7 +32,8 @@ 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_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \
		test_progs-no_alu32
		test_progs-no_alu32 \
		test_current_pid_tgid_new_ns

		# Also test bpf-gcc, if present
		ifneq ($(BPF_GCC),)

tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c

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		// SPDX-License-Identifier: GPL-2.0
		/* Copyright (c) 2020 Carlos Neira cneirabustos@gmail.com */
		#include <test_progs.h>
		#include <sys/stat.h>
		#include <sys/types.h>
		#include <unistd.h>
		#include <sys/syscall.h>

		struct bss {
		__u64 dev;
		__u64 ino;
		__u64 pid_tgid;
		__u64 user_pid_tgid;
		};

		void test_ns_current_pid_tgid(void)
		{
		const char *probe_name = "raw_tracepoint/sys_enter";
		const char *file = "test_ns_current_pid_tgid.o";
		int err, key = 0, duration = 0;
		struct bpf_link *link = NULL;
		struct bpf_program *prog;
		struct bpf_map *bss_map;
		struct bpf_object *obj;
		struct bss bss;
		struct stat st;
		__u64 id;

		obj = bpf_object__open_file(file, NULL);
		if (CHECK(IS_ERR(obj), "obj_open", "err %ld\n", PTR_ERR(obj)))
		return;

		err = bpf_object__load(obj);
		if (CHECK(err, "obj_load", "err %d errno %d\n", err, errno))
		goto cleanup;

		bss_map = bpf_object__find_map_by_name(obj, "test_ns_.bss");
		if (CHECK(!bss_map, "find_bss_map", "failed\n"))
		goto cleanup;

		prog = bpf_object__find_program_by_title(obj, probe_name);
		if (CHECK(!prog, "find_prog", "prog '%s' not found\n",
		probe_name))
		goto cleanup;

		memset(&bss, 0, sizeof(bss));
		pid_t tid = syscall(SYS_gettid);
		pid_t pid = getpid();

		id = (__u64) tid << 32 \| pid;
		bss.user_pid_tgid = id;

		if (CHECK_FAIL(stat("/proc/self/ns/pid", &st))) {
		perror("Failed to stat /proc/self/ns/pid");
		goto cleanup;
		}

		bss.dev = st.st_dev;
		bss.ino = st.st_ino;

		err = bpf_map_update_elem(bpf_map__fd(bss_map), &key, &bss, 0);
		if (CHECK(err, "setting_bss", "failed to set bss : %d\n", err))
		goto cleanup;

		link = bpf_program__attach_raw_tracepoint(prog, "sys_enter");
		if (CHECK(IS_ERR(link), "attach_raw_tp", "err %ld\n",
		PTR_ERR(link))) {
		link = NULL;
		goto cleanup;
		}

		/* trigger some syscalls */
		usleep(1);

		err = bpf_map_lookup_elem(bpf_map__fd(bss_map), &key, &bss);
		if (CHECK(err, "set_bss", "failed to get bss : %d\n", err))
		goto cleanup;

		if (CHECK(id != bss.pid_tgid, "Compare user pid/tgid vs. bpf pid/tgid",
		"User pid/tgid %llu BPF pid/tgid %llu\n", id, bss.pid_tgid))
		goto cleanup;
		cleanup:
		if (!link) {
		bpf_link__destroy(link);
		link = NULL;
		}
		bpf_object__close(obj);
		}

tools/testing/selftests/bpf/progs/test_ns_current_pid_tgid.c

0 → 100644

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		// SPDX-License-Identifier: GPL-2.0
		/* Copyright (c) 2019 Carlos Neira cneirabustos@gmail.com */

		#include <linux/bpf.h>
		#include <stdint.h>
		#include <bpf/bpf_helpers.h>

		static volatile struct {
		__u64 dev;
		__u64 ino;
		__u64 pid_tgid;
		__u64 user_pid_tgid;
		} res;

		SEC("raw_tracepoint/sys_enter")
		int trace(void *ctx)
		{
		__u64 ns_pid_tgid, expected_pid;
		struct bpf_pidns_info nsdata;
		__u32 key = 0;

		if (bpf_get_ns_current_pid_tgid(res.dev, res.ino, &nsdata,
		sizeof(struct bpf_pidns_info)))
		return 0;

		ns_pid_tgid = (__u64)nsdata.tgid << 32 \| nsdata.pid;
		expected_pid = res.user_pid_tgid;

		if (expected_pid != ns_pid_tgid)
		return 0;

		res.pid_tgid = ns_pid_tgid;

		return 0;
		}

		char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/test_current_pid_tgid_new_ns.c

0 → 100644

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Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0
		/* Copyright (c) 2020 Carlos Neira cneirabustos@gmail.com */
		#define _GNU_SOURCE
		#include <sys/stat.h>
		#include <sys/types.h>
		#include <unistd.h>
		#include <sys/syscall.h>
		#include <sched.h>
		#include <sys/wait.h>
		#include <sys/mount.h>
		#include "test_progs.h"

		#define CHECK_NEWNS(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; \
		})

		struct bss {
		__u64 dev;
		__u64 ino;
		__u64 pid_tgid;
		__u64 user_pid_tgid;
		};

		int main(int argc, char **argv)
		{
		pid_t pid;
		int exit_code = 1;
		struct stat st;

		printf("Testing bpf_get_ns_current_pid_tgid helper in new ns\n");

		if (stat("/proc/self/ns/pid", &st)) {
		perror("stat failed on /proc/self/ns/pid ns\n");
		printf("%s:FAILED\n", argv[0]);
		return exit_code;
		}

		if (CHECK_NEWNS(unshare(CLONE_NEWPID \| CLONE_NEWNS),
		"unshare CLONE_NEWPID \| CLONE_NEWNS", "error errno=%d\n", errno))
		return exit_code;

		pid = fork();
		if (pid == -1) {
		perror("Fork() failed\n");
		printf("%s:FAILED\n", argv[0]);
		return exit_code;
		}

		if (pid > 0) {
		int status;

		usleep(5);
		waitpid(pid, &status, 0);
		return 0;
		} else {

		pid = fork();
		if (pid == -1) {
		perror("Fork() failed\n");
		printf("%s:FAILED\n", argv[0]);
		return exit_code;
		}

		if (pid > 0) {
		int status;
		waitpid(pid, &status, 0);
		return 0;
		} else {
		if (CHECK_NEWNS(mount("none", "/proc", NULL, MS_PRIVATE\|MS_REC, NULL),
		"Unmounting proc", "Cannot umount proc! errno=%d\n", errno))
		return exit_code;

		if (CHECK_NEWNS(mount("proc", "/proc", "proc", MS_NOSUID\|MS_NOEXEC\|MS_NODEV, NULL),
		"Mounting proc", "Cannot mount proc! errno=%d\n", errno))
		return exit_code;

		const char *probe_name = "raw_tracepoint/sys_enter";
		const char *file = "test_ns_current_pid_tgid.o";
		struct bpf_link *link = NULL;
		struct bpf_program *prog;
		struct bpf_map *bss_map;
		struct bpf_object *obj;
		int exit_code = 1;
		int err, key = 0;
		struct bss bss;
		struct stat st;
		__u64 id;

		obj = bpf_object__open_file(file, NULL);
		if (CHECK_NEWNS(IS_ERR(obj), "obj_open", "err %ld\n", PTR_ERR(obj)))
		return exit_code;

		err = bpf_object__load(obj);
		if (CHECK_NEWNS(err, "obj_load", "err %d errno %d\n", err, errno))
		goto cleanup;

		bss_map = bpf_object__find_map_by_name(obj, "test_ns_.bss");
		if (CHECK_NEWNS(!bss_map, "find_bss_map", "failed\n"))
		goto cleanup;

		prog = bpf_object__find_program_by_title(obj, probe_name);
		if (CHECK_NEWNS(!prog, "find_prog", "prog '%s' not found\n",
		probe_name))
		goto cleanup;

		memset(&bss, 0, sizeof(bss));
		pid_t tid = syscall(SYS_gettid);
		pid_t pid = getpid();

		id = (__u64) tid << 32 \| pid;
		bss.user_pid_tgid = id;

		if (CHECK_NEWNS(stat("/proc/self/ns/pid", &st),
		"stat new ns", "Failed to stat /proc/self/ns/pid errno=%d\n", errno))
		goto cleanup;

		bss.dev = st.st_dev;
		bss.ino = st.st_ino;

		err = bpf_map_update_elem(bpf_map__fd(bss_map), &key, &bss, 0);
		if (CHECK_NEWNS(err, "setting_bss", "failed to set bss : %d\n", err))
		goto cleanup;

		link = bpf_program__attach_raw_tracepoint(prog, "sys_enter");
		if (CHECK_NEWNS(IS_ERR(link), "attach_raw_tp", "err %ld\n",
		PTR_ERR(link))) {
		link = NULL;
		goto cleanup;
		}

		/* trigger some syscalls */
		usleep(1);

		err = bpf_map_lookup_elem(bpf_map__fd(bss_map), &key, &bss);
		if (CHECK_NEWNS(err, "set_bss", "failed to get bss : %d\n", err))
		goto cleanup;

		if (CHECK_NEWNS(id != bss.pid_tgid, "Compare user pid/tgid vs. bpf pid/tgid",
		"User pid/tgid %llu BPF pid/tgid %llu\n", id, bss.pid_tgid))
		goto cleanup;

		exit_code = 0;
		printf("%s:PASS\n", argv[0]);
		cleanup:
		if (!link) {
		bpf_link__destroy(link);
		link = NULL;
		}
		bpf_object__close(obj);
		}
		}
		}

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