// SPDX-License-Identifier: GPL-2.0 #include <test_progs.h> #include <linux/btf.h>#include <bpf/bpf.h> #include "../test_btf.h" static inline int new_map(void){	const char *name = NULL;	__u32 max_entries = 1;	__u32 value_size = 8;	__u32 key_size = 4; 	return bpf_map_create(BPF_MAP_TYPE_ARRAY, name,			      key_size, value_size,			      max_entries, NULL);} static int new_btf(void){	struct btf_blob {		struct btf_header btf_hdr;		__u32 types[8];		__u32 str;	} raw_btf = {		.btf_hdr = {			.magic = BTF_MAGIC,			.version = BTF_VERSION,			.hdr_len = sizeof(struct btf_header),			.type_len = sizeof(raw_btf.types),			.str_off = offsetof(struct btf_blob, str) - offsetof(struct btf_blob, types),			.str_len = sizeof(raw_btf.str),		},		.types = {			/* long */			BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 64, 8),  /* [1] */			/* unsigned long */			BTF_TYPE_INT_ENC(0, 0, 0, 64, 8),  /* [2] */		},	}; 	return bpf_btf_load(&raw_btf, sizeof(raw_btf), NULL);} #define Close(FD) do {		\	if ((FD) >= 0) {	\		close(FD);	\		FD = -1;	\	}			\} while(0) static bool map_exists(__u32 id){	int fd; 	fd = bpf_map_get_fd_by_id(id);	if (fd >= 0) {		close(fd);		return true;	}	return false;} static bool btf_exists(__u32 id){	int fd; 	fd = bpf_btf_get_fd_by_id(id);	if (fd >= 0) {		close(fd);		return true;	}	return false;} static inline int bpf_prog_get_map_ids(int prog_fd, __u32 *nr_map_ids, __u32 *map_ids){	__u32 len = sizeof(struct bpf_prog_info);	struct bpf_prog_info info;	int err; 	memset(&info, 0, len);	info.nr_map_ids = *nr_map_ids;	info.map_ids = ptr_to_u64(map_ids); 	err = bpf_prog_get_info_by_fd(prog_fd, &info, &len);	if (!ASSERT_OK(err, "bpf_prog_get_info_by_fd"))		return -1; 	*nr_map_ids = info.nr_map_ids; 	return 0;} static int __load_test_prog(int map_fd, const int *fd_array, int fd_array_cnt){	/* A trivial program which uses one map */	struct bpf_insn insns[] = {		BPF_LD_MAP_FD(BPF_REG_1, map_fd),		BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),		BPF_MOV64_IMM(BPF_REG_0, 0),		BPF_EXIT_INSN(),	};	LIBBPF_OPTS(bpf_prog_load_opts, opts); 	opts.fd_array = fd_array;	opts.fd_array_cnt = fd_array_cnt; 	return bpf_prog_load(BPF_PROG_TYPE_XDP, NULL, "GPL", insns, ARRAY_SIZE(insns), &opts);} static int load_test_prog(const int *fd_array, int fd_array_cnt){	int map_fd;	int ret; 	map_fd = new_map();	if (!ASSERT_GE(map_fd, 0, "new_map"))		return map_fd; 	ret = __load_test_prog(map_fd, fd_array, fd_array_cnt);	close(map_fd);	return ret;} static bool check_expected_map_ids(int prog_fd, int expected, __u32 *map_ids, __u32 *nr_map_ids){	int err; 	err = bpf_prog_get_map_ids(prog_fd, nr_map_ids, map_ids);	if (!ASSERT_OK(err, "bpf_prog_get_map_ids"))		return false;	if (!ASSERT_EQ(*nr_map_ids, expected, "unexpected nr_map_ids"))		return false; 	return true;} /* * Load a program, which uses one map. No fd_array maps are present. * On return only one map is expected to be bound to prog. */static void check_fd_array_cnt__no_fd_array(void){	__u32 map_ids[16];	__u32 nr_map_ids;	int prog_fd = -1; 	prog_fd = load_test_prog(NULL, 0);	if (!ASSERT_GE(prog_fd, 0, "BPF_PROG_LOAD"))		return;	nr_map_ids = ARRAY_SIZE(map_ids);	check_expected_map_ids(prog_fd, 1, map_ids, &nr_map_ids);	close(prog_fd);} /* * Load a program, which uses one map, and pass two extra, non-equal, maps in * fd_array with fd_array_cnt=2. On return three maps are expected to be bound * to the program. */static void check_fd_array_cnt__fd_array_ok(void){	int extra_fds[2] = { -1, -1 };	__u32 map_ids[16];	__u32 nr_map_ids;	int prog_fd = -1; 	extra_fds[0] = new_map();	if (!ASSERT_GE(extra_fds[0], 0, "new_map"))		goto cleanup;	extra_fds[1] = new_map();	if (!ASSERT_GE(extra_fds[1], 0, "new_map"))		goto cleanup;	prog_fd = load_test_prog(extra_fds, 2);	if (!ASSERT_GE(prog_fd, 0, "BPF_PROG_LOAD"))		goto cleanup;	nr_map_ids = ARRAY_SIZE(map_ids);	if (!check_expected_map_ids(prog_fd, 3, map_ids, &nr_map_ids))		goto cleanup; 	/* maps should still exist when original file descriptors are closed */	Close(extra_fds[0]);	Close(extra_fds[1]);	if (!ASSERT_EQ(map_exists(map_ids[0]), true, "map_ids[0] should exist"))		goto cleanup;	if (!ASSERT_EQ(map_exists(map_ids[1]), true, "map_ids[1] should exist"))		goto cleanup; 	/* some fds might be invalid, so ignore return codes */cleanup:	Close(extra_fds[1]);	Close(extra_fds[0]);	Close(prog_fd);} /* * Load a program with a few extra maps duplicated in the fd_array. * After the load maps should only be referenced once. */static void check_fd_array_cnt__duplicated_maps(void){	int extra_fds[4] = { -1, -1, -1, -1 };	__u32 map_ids[16];	__u32 nr_map_ids;	int prog_fd = -1; 	extra_fds[0] = extra_fds[2] = new_map();	if (!ASSERT_GE(extra_fds[0], 0, "new_map"))		goto cleanup;	extra_fds[1] = extra_fds[3] = new_map();	if (!ASSERT_GE(extra_fds[1], 0, "new_map"))		goto cleanup;	prog_fd = load_test_prog(extra_fds, 4);	if (!ASSERT_GE(prog_fd, 0, "BPF_PROG_LOAD"))		goto cleanup;	nr_map_ids = ARRAY_SIZE(map_ids);	if (!check_expected_map_ids(prog_fd, 3, map_ids, &nr_map_ids))		goto cleanup; 	/* maps should still exist when original file descriptors are closed */	Close(extra_fds[0]);	Close(extra_fds[1]);	if (!ASSERT_EQ(map_exists(map_ids[0]), true, "map should exist"))		goto cleanup;	if (!ASSERT_EQ(map_exists(map_ids[1]), true, "map should exist"))		goto cleanup; 	/* some fds might be invalid, so ignore return codes */cleanup:	Close(extra_fds[1]);	Close(extra_fds[0]);	Close(prog_fd);} /* * Check that if maps which are referenced by a program are * passed in fd_array, then they will be referenced only once */static void check_fd_array_cnt__referenced_maps_in_fd_array(void){	int extra_fds[1] = { -1 };	__u32 map_ids[16];	__u32 nr_map_ids;	int prog_fd = -1; 	extra_fds[0] = new_map();	if (!ASSERT_GE(extra_fds[0], 0, "new_map"))		goto cleanup;	prog_fd = __load_test_prog(extra_fds[0], extra_fds, 1);	if (!ASSERT_GE(prog_fd, 0, "BPF_PROG_LOAD"))		goto cleanup;	nr_map_ids = ARRAY_SIZE(map_ids);	if (!check_expected_map_ids(prog_fd, 1, map_ids, &nr_map_ids))		goto cleanup; 	/* map should still exist when original file descriptor is closed */	Close(extra_fds[0]);	if (!ASSERT_EQ(map_exists(map_ids[0]), true, "map should exist"))		goto cleanup; 	/* some fds might be invalid, so ignore return codes */cleanup:	Close(extra_fds[0]);	Close(prog_fd);} static int get_btf_id_by_fd(int btf_fd, __u32 *id){	struct bpf_btf_info info;	__u32 info_len = sizeof(info);	int err; 	memset(&info, 0, info_len);	err = bpf_btf_get_info_by_fd(btf_fd, &info, &info_len);	if (err)		return err;	if (id)		*id = info.id;	return 0;} /* * Check that fd_array operates properly for btfs. Namely, to check that * passing a btf fd in fd_array increases its reference count, do the * following: *  1) Create a new btf, it's referenced only by a file descriptor, so refcnt=1 *  2) Load a BPF prog with fd_array[0] = btf_fd; now btf's refcnt=2 *  3) Close the btf_fd, now refcnt=1 * Wait and check that BTF still exists. */static void check_fd_array_cnt__referenced_btfs(void){	int extra_fds[1] = { -1 };	int prog_fd = -1;	__u32 btf_id;	int tries;	int err; 	extra_fds[0] = new_btf();	if (!ASSERT_GE(extra_fds[0], 0, "new_btf"))		goto cleanup;	prog_fd = load_test_prog(extra_fds, 1);	if (!ASSERT_GE(prog_fd, 0, "BPF_PROG_LOAD"))		goto cleanup; 	/* btf should still exist when original file descriptor is closed */	err = get_btf_id_by_fd(extra_fds[0], &btf_id);	if (!ASSERT_EQ(err, 0, "get_btf_id_by_fd"))		goto cleanup; 	Close(extra_fds[0]); 	if (!ASSERT_GE(kern_sync_rcu(), 0, "kern_sync_rcu 1"))		goto cleanup; 	if (!ASSERT_EQ(btf_exists(btf_id), true, "btf should exist"))		goto cleanup; 	Close(prog_fd); 	/* The program is freed by a workqueue, so no reliable	 * way to sync, so just wait a bit (max ~1 second). */	for (tries = 100; tries >= 0; tries--) {		usleep(1000); 		if (!btf_exists(btf_id))			break; 		if (tries)			continue; 		PRINT_FAIL("btf should have been freed");	} 	/* some fds might be invalid, so ignore return codes */cleanup:	Close(extra_fds[0]);	Close(prog_fd);} /* * Test that a program with trash in fd_array can't be loaded: * only map and BTF file descriptors should be accepted. */static void check_fd_array_cnt__fd_array_with_trash(void){	int extra_fds[3] = { -1, -1, -1 };	int prog_fd = -1; 	extra_fds[0] = new_map();	if (!ASSERT_GE(extra_fds[0], 0, "new_map"))		goto cleanup;	extra_fds[1] = new_btf();	if (!ASSERT_GE(extra_fds[1], 0, "new_btf"))		goto cleanup; 	/* trash 1: not a file descriptor */	extra_fds[2] = 0xbeef;	prog_fd = load_test_prog(extra_fds, 3);	if (!ASSERT_EQ(prog_fd, -EBADF, "prog should have been rejected with -EBADF"))		goto cleanup; 	/* trash 2: not a map or btf */	extra_fds[2] = socket(AF_INET, SOCK_STREAM, 0);	if (!ASSERT_GE(extra_fds[2], 0, "socket"))		goto cleanup; 	prog_fd = load_test_prog(extra_fds, 3);	if (!ASSERT_EQ(prog_fd, -EINVAL, "prog should have been rejected with -EINVAL"))		goto cleanup; 	/* Validate that the prog is ok if trash is removed */	Close(extra_fds[2]);	extra_fds[2] = new_btf();	if (!ASSERT_GE(extra_fds[2], 0, "new_btf"))		goto cleanup; 	prog_fd = load_test_prog(extra_fds, 3);	if (!ASSERT_GE(prog_fd, 0, "prog should have been loaded"))		goto cleanup; 	/* some fds might be invalid, so ignore return codes */cleanup:	Close(extra_fds[2]);	Close(extra_fds[1]);	Close(extra_fds[0]);} /* * Test that a program with too big fd_array can't be loaded. */static void check_fd_array_cnt__fd_array_too_big(void){	int extra_fds[65];	int prog_fd = -1;	int i; 	for (i = 0; i < 65; i++) {		extra_fds[i] = new_map();		if (!ASSERT_GE(extra_fds[i], 0, "new_map"))			goto cleanup_fds;	} 	prog_fd = load_test_prog(extra_fds, 65);	ASSERT_EQ(prog_fd, -E2BIG, "prog should have been rejected with -E2BIG"); cleanup_fds:	while (i-- > 0)		Close(extra_fds[i]);} void test_fd_array_cnt(void){	if (test__start_subtest("no-fd-array"))		check_fd_array_cnt__no_fd_array(); 	if (test__start_subtest("fd-array-ok"))		check_fd_array_cnt__fd_array_ok(); 	if (test__start_subtest("fd-array-dup-input"))		check_fd_array_cnt__duplicated_maps(); 	if (test__start_subtest("fd-array-ref-maps-in-array"))		check_fd_array_cnt__referenced_maps_in_fd_array(); 	if (test__start_subtest("fd-array-ref-btfs"))		check_fd_array_cnt__referenced_btfs(); 	if (test__start_subtest("fd-array-trash-input"))		check_fd_array_cnt__fd_array_with_trash(); 	if (test__start_subtest("fd-array-2big"))		check_fd_array_cnt__fd_array_too_big();}