diff options
Diffstat (limited to 'tools/lib/bpf/libbpf.c')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 1113 |
1 files changed, 662 insertions, 451 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 5401f2df463d..e9c641a2fb20 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -60,6 +60,8 @@ #define BPF_FS_MAGIC 0xcafe4a11 #endif +#define MAX_EVENT_NAME_LEN 64 + #define BPF_FS_DEFAULT_PATH "/sys/fs/bpf" #define BPF_INSN_SZ (sizeof(struct bpf_insn)) @@ -133,6 +135,7 @@ static const char * const attach_type_name[] = { [BPF_NETKIT_PRIMARY] = "netkit_primary", [BPF_NETKIT_PEER] = "netkit_peer", [BPF_TRACE_KPROBE_SESSION] = "trace_kprobe_session", + [BPF_TRACE_UPROBE_SESSION] = "trace_uprobe_session", }; static const char * const link_type_name[] = { @@ -229,7 +232,30 @@ static const char * const prog_type_name[] = { static int __base_pr(enum libbpf_print_level level, const char *format, va_list args) { - if (level == LIBBPF_DEBUG) + const char *env_var = "LIBBPF_LOG_LEVEL"; + static enum libbpf_print_level min_level = LIBBPF_INFO; + static bool initialized; + + if (!initialized) { + char *verbosity; + + initialized = true; + verbosity = getenv(env_var); + if (verbosity) { + if (strcasecmp(verbosity, "warn") == 0) + min_level = LIBBPF_WARN; + else if (strcasecmp(verbosity, "debug") == 0) + min_level = LIBBPF_DEBUG; + else if (strcasecmp(verbosity, "info") == 0) + min_level = LIBBPF_INFO; + else + fprintf(stderr, "libbpf: unrecognized '%s' envvar value: '%s', should be one of 'warn', 'debug', or 'info'.\n", + env_var, verbosity); + } + } + + /* if too verbose, skip logging */ + if (level > min_level) return 0; return vfprintf(stderr, format, args); @@ -260,7 +286,7 @@ void libbpf_print(enum libbpf_print_level level, const char *format, ...) old_errno = errno; va_start(args, format); - __libbpf_pr(level, format, args); + print_fn(level, format, args); va_end(args); errno = old_errno; @@ -473,8 +499,6 @@ struct bpf_program { }; struct bpf_struct_ops { - const char *tname; - const struct btf_type *type; struct bpf_program **progs; __u32 *kern_func_off; /* e.g. struct tcp_congestion_ops in bpf_prog's btf format */ @@ -549,6 +573,7 @@ struct bpf_map { bool pinned; bool reused; bool autocreate; + bool autoattach; __u64 map_extra; }; @@ -647,11 +672,18 @@ struct elf_state { struct usdt_manager; +enum bpf_object_state { + OBJ_OPEN, + OBJ_PREPARED, + OBJ_LOADED, +}; + struct bpf_object { char name[BPF_OBJ_NAME_LEN]; char license[64]; __u32 kern_version; + enum bpf_object_state state; struct bpf_program *programs; size_t nr_programs; struct bpf_map *maps; @@ -663,7 +695,6 @@ struct bpf_object { int nr_extern; int kconfig_map_idx; - bool loaded; bool has_subcalls; bool has_rodata; @@ -672,6 +703,8 @@ struct bpf_object { /* Information when doing ELF related work. Only valid if efile.elf is not NULL */ struct elf_state efile; + unsigned char byteorder; + struct btf *btf; struct btf_ext *btf_ext; @@ -865,7 +898,7 @@ bpf_object__add_programs(struct bpf_object *obj, Elf_Data *sec_data, return -LIBBPF_ERRNO__FORMAT; } - if (sec_off + prog_sz > sec_sz) { + if (sec_off + prog_sz > sec_sz || sec_off + prog_sz < sec_off) { pr_warn("sec '%s': program at offset %zu crosses section boundary\n", sec_name, sec_off); return -LIBBPF_ERRNO__FORMAT; @@ -918,6 +951,20 @@ bpf_object__add_programs(struct bpf_object *obj, Elf_Data *sec_data, return 0; } +static void bpf_object_bswap_progs(struct bpf_object *obj) +{ + struct bpf_program *prog = obj->programs; + struct bpf_insn *insn; + int p, i; + + for (p = 0; p < obj->nr_programs; p++, prog++) { + insn = prog->insns; + for (i = 0; i < prog->insns_cnt; i++, insn++) + bpf_insn_bswap(insn); + } + pr_debug("converted %zu BPF programs to native byte order\n", obj->nr_programs); +} + static const struct btf_member * find_member_by_offset(const struct btf_type *t, __u32 bit_offset) { @@ -964,7 +1011,7 @@ find_struct_ops_kern_types(struct bpf_object *obj, const char *tname_raw, { const struct btf_type *kern_type, *kern_vtype; const struct btf_member *kern_data_member; - struct btf *btf; + struct btf *btf = NULL; __s32 kern_vtype_id, kern_type_id; char tname[256]; __u32 i; @@ -1059,11 +1106,14 @@ static int bpf_object_adjust_struct_ops_autoload(struct bpf_object *obj) continue; for (j = 0; j < obj->nr_maps; ++j) { + const struct btf_type *type; + map = &obj->maps[j]; if (!bpf_map__is_struct_ops(map)) continue; - vlen = btf_vlen(map->st_ops->type); + type = btf__type_by_id(obj->btf, map->st_ops->type_id); + vlen = btf_vlen(type); for (k = 0; k < vlen; ++k) { slot_prog = map->st_ops->progs[k]; if (prog != slot_prog) @@ -1091,14 +1141,14 @@ static int bpf_map__init_kern_struct_ops(struct bpf_map *map) const struct btf *btf = obj->btf; struct bpf_struct_ops *st_ops; const struct btf *kern_btf; - struct module_btf *mod_btf; + struct module_btf *mod_btf = NULL; void *data, *kern_data; const char *tname; int err; st_ops = map->st_ops; - type = st_ops->type; - tname = st_ops->tname; + type = btf__type_by_id(btf, st_ops->type_id); + tname = btf__name_by_offset(btf, type->name_off); err = find_struct_ops_kern_types(obj, tname, &mod_btf, &kern_type, &kern_type_id, &kern_vtype, &kern_vtype_id, @@ -1377,6 +1427,7 @@ static int init_struct_ops_maps(struct bpf_object *obj, const char *sec_name, map->def.value_size = type->size; map->def.max_entries = 1; map->def.map_flags = strcmp(sec_name, STRUCT_OPS_LINK_SEC) == 0 ? BPF_F_LINK : 0; + map->autoattach = true; map->st_ops = calloc(1, sizeof(*map->st_ops)); if (!map->st_ops) @@ -1398,8 +1449,6 @@ static int init_struct_ops_maps(struct bpf_object *obj, const char *sec_name, memcpy(st_ops->data, data->d_buf + vsi->offset, type->size); - st_ops->tname = tname; - st_ops->type = type; st_ops->type_id = type_id; pr_debug("struct_ops init: struct %s(type_id=%u) %s found at offset %u\n", @@ -1470,7 +1519,7 @@ static struct bpf_object *bpf_object__new(const char *path, obj->kconfig_map_idx = -1; obj->kern_version = get_kernel_version(); - obj->loaded = false; + obj->state = OBJ_OPEN; return obj; } @@ -1482,6 +1531,7 @@ static void bpf_object__elf_finish(struct bpf_object *obj) elf_end(obj->efile.elf); obj->efile.elf = NULL; + obj->efile.ehdr = NULL; obj->efile.symbols = NULL; obj->efile.arena_data = NULL; @@ -1509,11 +1559,8 @@ static int bpf_object__elf_init(struct bpf_object *obj) } else { obj->efile.fd = open(obj->path, O_RDONLY | O_CLOEXEC); if (obj->efile.fd < 0) { - char errmsg[STRERR_BUFSIZE], *cp; - err = -errno; - cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); - pr_warn("elf: failed to open %s: %s\n", obj->path, cp); + pr_warn("elf: failed to open %s: %s\n", obj->path, errstr(err)); return err; } @@ -1547,6 +1594,16 @@ static int bpf_object__elf_init(struct bpf_object *obj) goto errout; } + /* Validate ELF object endianness... */ + if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB && + ehdr->e_ident[EI_DATA] != ELFDATA2MSB) { + err = -LIBBPF_ERRNO__ENDIAN; + pr_warn("elf: '%s' has unknown byte order\n", obj->path); + goto errout; + } + /* and save after bpf_object_open() frees ELF data */ + obj->byteorder = ehdr->e_ident[EI_DATA]; + if (elf_getshdrstrndx(elf, &obj->efile.shstrndx)) { pr_warn("elf: failed to get section names section index for %s: %s\n", obj->path, elf_errmsg(-1)); @@ -1575,19 +1632,15 @@ errout: return err; } -static int bpf_object__check_endianness(struct bpf_object *obj) +static bool is_native_endianness(struct bpf_object *obj) { #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ - if (obj->efile.ehdr->e_ident[EI_DATA] == ELFDATA2LSB) - return 0; + return obj->byteorder == ELFDATA2LSB; #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ - if (obj->efile.ehdr->e_ident[EI_DATA] == ELFDATA2MSB) - return 0; + return obj->byteorder == ELFDATA2MSB; #else # error "Unrecognized __BYTE_ORDER__" #endif - pr_warn("elf: endianness mismatch in %s.\n", obj->path); - return -LIBBPF_ERRNO__ENDIAN; } static int @@ -1674,24 +1727,27 @@ static Elf64_Sym *find_elf_var_sym(const struct bpf_object *obj, const char *nam return ERR_PTR(-ENOENT); } -/* Some versions of Android don't provide memfd_create() in their libc - * implementation, so avoid complications and just go straight to Linux - * syscall. - */ -static int sys_memfd_create(const char *name, unsigned flags) -{ - return syscall(__NR_memfd_create, name, flags); -} - #ifndef MFD_CLOEXEC #define MFD_CLOEXEC 0x0001U #endif +#ifndef MFD_NOEXEC_SEAL +#define MFD_NOEXEC_SEAL 0x0008U +#endif static int create_placeholder_fd(void) { + unsigned int flags = MFD_CLOEXEC | MFD_NOEXEC_SEAL; + const char *name = "libbpf-placeholder-fd"; int fd; - fd = ensure_good_fd(sys_memfd_create("libbpf-placeholder-fd", MFD_CLOEXEC)); + fd = ensure_good_fd(sys_memfd_create(name, flags)); + if (fd >= 0) + return fd; + else if (errno != EINVAL) + return -errno; + + /* Possibly running on kernel without MFD_NOEXEC_SEAL */ + fd = ensure_good_fd(sys_memfd_create(name, flags & ~MFD_NOEXEC_SEAL)); if (fd < 0) return -errno; return fd; @@ -1824,7 +1880,7 @@ static char *internal_map_name(struct bpf_object *obj, const char *real_name) snprintf(map_name, sizeof(map_name), "%.*s%.*s", pfx_len, obj->name, sfx_len, real_name); - /* sanitise map name to characters allowed by kernel */ + /* sanities map name to characters allowed by kernel */ for (p = map_name; *p && p < map_name + sizeof(map_name); p++) if (!isalnum(*p) && *p != '_' && *p != '.') *p = '_'; @@ -1913,8 +1969,7 @@ bpf_object__init_internal_map(struct bpf_object *obj, enum libbpf_map_type type, if (map->mmaped == MAP_FAILED) { err = -errno; map->mmaped = NULL; - pr_warn("failed to alloc map '%s' content buffer: %d\n", - map->name, err); + pr_warn("failed to alloc map '%s' content buffer: %s\n", map->name, errstr(err)); zfree(&map->real_name); zfree(&map->name); return err; @@ -2050,7 +2105,7 @@ static int set_kcfg_value_str(struct extern_desc *ext, char *ext_val, } len = strlen(value); - if (value[len - 1] != '"') { + if (len < 2 || value[len - 1] != '"') { pr_warn("extern (kcfg) '%s': invalid string config '%s'\n", ext->name, value); return -EINVAL; @@ -2078,7 +2133,7 @@ static int parse_u64(const char *value, __u64 *res) *res = strtoull(value, &value_end, 0); if (errno) { err = -errno; - pr_warn("failed to parse '%s' as integer: %d\n", value, err); + pr_warn("failed to parse '%s': %s\n", value, errstr(err)); return err; } if (*value_end) { @@ -2244,8 +2299,8 @@ static int bpf_object__read_kconfig_file(struct bpf_object *obj, void *data) while (gzgets(file, buf, sizeof(buf))) { err = bpf_object__process_kconfig_line(obj, buf, data); if (err) { - pr_warn("error parsing system Kconfig line '%s': %d\n", - buf, err); + pr_warn("error parsing system Kconfig line '%s': %s\n", + buf, errstr(err)); goto out; } } @@ -2265,15 +2320,15 @@ static int bpf_object__read_kconfig_mem(struct bpf_object *obj, file = fmemopen((void *)config, strlen(config), "r"); if (!file) { err = -errno; - pr_warn("failed to open in-memory Kconfig: %d\n", err); + pr_warn("failed to open in-memory Kconfig: %s\n", errstr(err)); return err; } while (fgets(buf, sizeof(buf), file)) { err = bpf_object__process_kconfig_line(obj, buf, data); if (err) { - pr_warn("error parsing in-memory Kconfig line '%s': %d\n", - buf, err); + pr_warn("error parsing in-memory Kconfig line '%s': %s\n", + buf, errstr(err)); break; } } @@ -3188,7 +3243,7 @@ static int bpf_object__init_btf(struct bpf_object *obj, err = libbpf_get_error(obj->btf); if (err) { obj->btf = NULL; - pr_warn("Error loading ELF section %s: %d.\n", BTF_ELF_SEC, err); + pr_warn("Error loading ELF section %s: %s.\n", BTF_ELF_SEC, errstr(err)); goto out; } /* enforce 8-byte pointers for BPF-targeted BTFs */ @@ -3206,8 +3261,8 @@ static int bpf_object__init_btf(struct bpf_object *obj, obj->btf_ext = btf_ext__new(btf_ext_data->d_buf, btf_ext_data->d_size); err = libbpf_get_error(obj->btf_ext); if (err) { - pr_warn("Error loading ELF section %s: %d. Ignored and continue.\n", - BTF_EXT_ELF_SEC, err); + pr_warn("Error loading ELF section %s: %s. Ignored and continue.\n", + BTF_EXT_ELF_SEC, errstr(err)); obj->btf_ext = NULL; goto out; } @@ -3299,8 +3354,8 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf, if (t->size == 0) { err = find_elf_sec_sz(obj, sec_name, &size); if (err || !size) { - pr_debug("sec '%s': failed to determine size from ELF: size %u, err %d\n", - sec_name, size, err); + pr_debug("sec '%s': failed to determine size from ELF: size %u, err %s\n", + sec_name, size, errstr(err)); return -ENOENT; } @@ -3454,7 +3509,7 @@ static int bpf_object__load_vmlinux_btf(struct bpf_object *obj, bool force) obj->btf_vmlinux = btf__load_vmlinux_btf(); err = libbpf_get_error(obj->btf_vmlinux); if (err) { - pr_warn("Error loading vmlinux BTF: %d\n", err); + pr_warn("Error loading vmlinux BTF: %s\n", errstr(err)); obj->btf_vmlinux = NULL; return err; } @@ -3557,11 +3612,14 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) report: if (err) { btf_mandatory = kernel_needs_btf(obj); - pr_warn("Error loading .BTF into kernel: %d. %s\n", err, - btf_mandatory ? "BTF is mandatory, can't proceed." - : "BTF is optional, ignoring."); - if (!btf_mandatory) + if (btf_mandatory) { + pr_warn("Error loading .BTF into kernel: %s. BTF is mandatory, can't proceed.\n", + errstr(err)); + } else { + pr_info("Error loading .BTF into kernel: %s. BTF is optional, ignoring.\n", + errstr(err)); err = 0; + } } return err; } @@ -3929,6 +3987,10 @@ static int bpf_object__elf_collect(struct bpf_object *obj) return -LIBBPF_ERRNO__FORMAT; } + /* change BPF program insns to native endianness for introspection */ + if (!is_native_endianness(obj)) + bpf_object_bswap_progs(obj); + /* sort BPF programs by section name and in-section instruction offset * for faster search */ @@ -3961,7 +4023,7 @@ static bool sym_is_subprog(const Elf64_Sym *sym, int text_shndx) return true; /* global function */ - return bind == STB_GLOBAL && type == STT_FUNC; + return (bind == STB_GLOBAL || bind == STB_WEAK) && type == STT_FUNC; } static int find_extern_btf_id(const struct btf *btf, const char *ext_name) @@ -4365,7 +4427,7 @@ static int bpf_object__collect_externs(struct bpf_object *obj) static bool prog_is_subprog(const struct bpf_object *obj, const struct bpf_program *prog) { - return prog->sec_idx == obj->efile.text_shndx && obj->nr_programs > 1; + return prog->sec_idx == obj->efile.text_shndx; } struct bpf_program * @@ -4759,8 +4821,8 @@ static int bpf_get_map_info_from_fdinfo(int fd, struct bpf_map_info *info) fp = fopen(file, "re"); if (!fp) { err = -errno; - pr_warn("failed to open %s: %d. No procfs support?\n", file, - err); + pr_warn("failed to open %s: %s. No procfs support?\n", file, + errstr(err)); return err; } @@ -4782,6 +4844,11 @@ static int bpf_get_map_info_from_fdinfo(int fd, struct bpf_map_info *info) return 0; } +static bool map_is_created(const struct bpf_map *map) +{ + return map->obj->state >= OBJ_PREPARED || map->reused; +} + bool bpf_map__autocreate(const struct bpf_map *map) { return map->autocreate; @@ -4789,13 +4856,27 @@ bool bpf_map__autocreate(const struct bpf_map *map) int bpf_map__set_autocreate(struct bpf_map *map, bool autocreate) { - if (map->obj->loaded) + if (map_is_created(map)) return libbpf_err(-EBUSY); map->autocreate = autocreate; return 0; } +int bpf_map__set_autoattach(struct bpf_map *map, bool autoattach) +{ + if (!bpf_map__is_struct_ops(map)) + return libbpf_err(-EINVAL); + + map->autoattach = autoattach; + return 0; +} + +bool bpf_map__autoattach(const struct bpf_map *map) +{ + return map->autoattach; +} + int bpf_map__reuse_fd(struct bpf_map *map, int fd) { struct bpf_map_info info; @@ -4869,7 +4950,7 @@ struct bpf_map *bpf_map__inner_map(struct bpf_map *map) int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries) { - if (map->obj->loaded) + if (map_is_created(map)) return libbpf_err(-EBUSY); map->def.max_entries = max_entries; @@ -4901,8 +4982,8 @@ static int bpf_object_prepare_token(struct bpf_object *obj) bpffs_fd = open(bpffs_path, O_DIRECTORY, O_RDWR); if (bpffs_fd < 0) { err = -errno; - __pr(level, "object '%s': failed (%d) to open BPF FS mount at '%s'%s\n", - obj->name, err, bpffs_path, + __pr(level, "object '%s': failed (%s) to open BPF FS mount at '%s'%s\n", + obj->name, errstr(err), bpffs_path, mandatory ? "" : ", skipping optional step..."); return mandatory ? err : 0; } @@ -4936,7 +5017,6 @@ static int bpf_object_prepare_token(struct bpf_object *obj) static int bpf_object__probe_loading(struct bpf_object *obj) { - char *cp, errmsg[STRERR_BUFSIZE]; struct bpf_insn insns[] = { BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), @@ -4952,7 +5032,8 @@ bpf_object__probe_loading(struct bpf_object *obj) ret = bump_rlimit_memlock(); if (ret) - pr_warn("Failed to bump RLIMIT_MEMLOCK (err = %d), you might need to do it explicitly!\n", ret); + pr_warn("Failed to bump RLIMIT_MEMLOCK (err = %s), you might need to do it explicitly!\n", + errstr(ret)); /* make sure basic loading works */ ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, &opts); @@ -4960,11 +5041,8 @@ bpf_object__probe_loading(struct bpf_object *obj) ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, &opts); if (ret < 0) { ret = errno; - cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); - pr_warn("Error in %s():%s(%d). Couldn't load trivial BPF " - "program. Make sure your kernel supports BPF " - "(CONFIG_BPF_SYSCALL=y) and/or that RLIMIT_MEMLOCK is " - "set to big enough value.\n", __func__, cp, ret); + pr_warn("Error in %s(): %s. Couldn't load trivial BPF program. Make sure your kernel supports BPF (CONFIG_BPF_SYSCALL=y) and/or that RLIMIT_MEMLOCK is set to big enough value.\n", + __func__, errstr(ret)); return -ret; } close(ret); @@ -4989,7 +5067,6 @@ bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id) static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd) { struct bpf_map_info map_info; - char msg[STRERR_BUFSIZE]; __u32 map_info_len = sizeof(map_info); int err; @@ -4999,7 +5076,7 @@ static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd) err = bpf_get_map_info_from_fdinfo(map_fd, &map_info); if (err) { pr_warn("failed to get map info for map FD %d: %s\n", map_fd, - libbpf_strerror_r(errno, msg, sizeof(msg))); + errstr(err)); return false; } @@ -5014,7 +5091,6 @@ static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd) static int bpf_object__reuse_map(struct bpf_map *map) { - char *cp, errmsg[STRERR_BUFSIZE]; int err, pin_fd; pin_fd = bpf_obj_get(map->pin_path); @@ -5026,9 +5102,8 @@ bpf_object__reuse_map(struct bpf_map *map) return 0; } - cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); pr_warn("couldn't retrieve pinned map '%s': %s\n", - map->pin_path, cp); + map->pin_path, errstr(err)); return err; } @@ -5054,8 +5129,8 @@ static int bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) { enum libbpf_map_type map_type = map->libbpf_type; - char *cp, errmsg[STRERR_BUFSIZE]; int err, zero = 0; + size_t mmap_sz; if (obj->gen_loader) { bpf_gen__map_update_elem(obj->gen_loader, map - obj->maps, @@ -5068,9 +5143,8 @@ bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) err = bpf_map_update_elem(map->fd, &zero, map->mmaped, 0); if (err) { err = -errno; - cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); - pr_warn("Error setting initial map(%s) contents: %s\n", - map->name, cp); + pr_warn("map '%s': failed to set initial contents: %s\n", + bpf_map__name(map), errstr(err)); return err; } @@ -5079,22 +5153,48 @@ bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) err = bpf_map_freeze(map->fd); if (err) { err = -errno; - cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); - pr_warn("Error freezing map(%s) as read-only: %s\n", - map->name, cp); + pr_warn("map '%s': failed to freeze as read-only: %s\n", + bpf_map__name(map), errstr(err)); + return err; + } + } + + /* Remap anonymous mmap()-ed "map initialization image" as + * a BPF map-backed mmap()-ed memory, but preserving the same + * memory address. This will cause kernel to change process' + * page table to point to a different piece of kernel memory, + * but from userspace point of view memory address (and its + * contents, being identical at this point) will stay the + * same. This mapping will be released by bpf_object__close() + * as per normal clean up procedure. + */ + mmap_sz = bpf_map_mmap_sz(map); + if (map->def.map_flags & BPF_F_MMAPABLE) { + void *mmaped; + int prot; + + if (map->def.map_flags & BPF_F_RDONLY_PROG) + prot = PROT_READ; + else + prot = PROT_READ | PROT_WRITE; + mmaped = mmap(map->mmaped, mmap_sz, prot, MAP_SHARED | MAP_FIXED, map->fd, 0); + if (mmaped == MAP_FAILED) { + err = -errno; + pr_warn("map '%s': failed to re-mmap() contents: %s\n", + bpf_map__name(map), errstr(err)); return err; } + map->mmaped = mmaped; + } else if (map->mmaped) { + munmap(map->mmaped, mmap_sz); + map->mmaped = NULL; } + return 0; } static void bpf_map__destroy(struct bpf_map *map); -static bool map_is_created(const struct bpf_map *map) -{ - return map->obj->loaded || map->reused; -} - static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, bool is_inner) { LIBBPF_OPTS(bpf_map_create_opts, create_attr); @@ -5133,8 +5233,8 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b return err; err = bpf_object__create_map(obj, map->inner_map, true); if (err) { - pr_warn("map '%s': failed to create inner map: %d\n", - map->name, err); + pr_warn("map '%s': failed to create inner map: %s\n", + map->name, errstr(err)); return err; } map->inner_map_fd = map->inner_map->fd; @@ -5188,12 +5288,9 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b def->max_entries, &create_attr); } if (map_fd < 0 && (create_attr.btf_key_type_id || create_attr.btf_value_type_id)) { - char *cp, errmsg[STRERR_BUFSIZE]; - err = -errno; - cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); - pr_warn("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n", - map->name, cp, err); + pr_warn("Error in bpf_create_map_xattr(%s): %s. Retrying without BTF.\n", + map->name, errstr(err)); create_attr.btf_fd = 0; create_attr.btf_key_type_id = 0; create_attr.btf_value_type_id = 0; @@ -5248,8 +5345,8 @@ static int init_map_in_map_slots(struct bpf_object *obj, struct bpf_map *map) } if (err) { err = -errno; - pr_warn("map '%s': failed to initialize slot [%d] to map '%s' fd=%d: %d\n", - map->name, i, targ_map->name, fd, err); + pr_warn("map '%s': failed to initialize slot [%d] to map '%s' fd=%d: %s\n", + map->name, i, targ_map->name, fd, errstr(err)); return err; } pr_debug("map '%s': slot [%d] set to map '%s' fd=%d\n", @@ -5281,8 +5378,8 @@ static int init_prog_array_slots(struct bpf_object *obj, struct bpf_map *map) err = bpf_map_update_elem(map->fd, &i, &fd, 0); if (err) { err = -errno; - pr_warn("map '%s': failed to initialize slot [%d] to prog '%s' fd=%d: %d\n", - map->name, i, targ_prog->name, fd, err); + pr_warn("map '%s': failed to initialize slot [%d] to prog '%s' fd=%d: %s\n", + map->name, i, targ_prog->name, fd, errstr(err)); return err; } pr_debug("map '%s': slot [%d] set to prog '%s' fd=%d\n", @@ -5335,7 +5432,6 @@ static int bpf_object__create_maps(struct bpf_object *obj) { struct bpf_map *map; - char *cp, errmsg[STRERR_BUFSIZE]; unsigned int i, j; int err; bool retried; @@ -5401,8 +5497,7 @@ retry: err = bpf_object__populate_internal_map(obj, map); if (err < 0) goto err_out; - } - if (map->def.type == BPF_MAP_TYPE_ARENA) { + } else if (map->def.type == BPF_MAP_TYPE_ARENA) { map->mmaped = mmap((void *)(long)map->map_extra, bpf_map_mmap_sz(map), PROT_READ | PROT_WRITE, map->map_extra ? MAP_SHARED | MAP_FIXED : MAP_SHARED, @@ -5410,8 +5505,8 @@ retry: if (map->mmaped == MAP_FAILED) { err = -errno; map->mmaped = NULL; - pr_warn("map '%s': failed to mmap arena: %d\n", - map->name, err); + pr_warn("map '%s': failed to mmap arena: %s\n", + map->name, errstr(err)); return err; } if (obj->arena_data) { @@ -5433,8 +5528,8 @@ retry: retried = true; goto retry; } - pr_warn("map '%s': failed to auto-pin at '%s': %d\n", - map->name, map->pin_path, err); + pr_warn("map '%s': failed to auto-pin at '%s': %s\n", + map->name, map->pin_path, errstr(err)); goto err_out; } } @@ -5443,8 +5538,7 @@ retry: return 0; err_out: - cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); - pr_warn("map '%s': failed to create: %s(%d)\n", map->name, cp, err); + pr_warn("map '%s': failed to create: %s\n", map->name, errstr(err)); pr_perm_msg(err); for (j = 0; j < i; j++) zclose(obj->maps[j].fd); @@ -5568,7 +5662,7 @@ static int load_module_btfs(struct bpf_object *obj) } if (err) { err = -errno; - pr_warn("failed to iterate BTF objects: %d\n", err); + pr_warn("failed to iterate BTF objects: %s\n", errstr(err)); return err; } @@ -5577,7 +5671,7 @@ static int load_module_btfs(struct bpf_object *obj) if (errno == ENOENT) continue; /* expected race: BTF was unloaded */ err = -errno; - pr_warn("failed to get BTF object #%d FD: %d\n", id, err); + pr_warn("failed to get BTF object #%d FD: %s\n", id, errstr(err)); return err; } @@ -5589,7 +5683,7 @@ static int load_module_btfs(struct bpf_object *obj) err = bpf_btf_get_info_by_fd(fd, &info, &len); if (err) { err = -errno; - pr_warn("failed to get BTF object #%d info: %d\n", id, err); + pr_warn("failed to get BTF object #%d info: %s\n", id, errstr(err)); goto err_out; } @@ -5602,8 +5696,8 @@ static int load_module_btfs(struct bpf_object *obj) btf = btf_get_from_fd(fd, obj->btf_vmlinux); err = libbpf_get_error(btf); if (err) { - pr_warn("failed to load module [%s]'s BTF object #%d: %d\n", - name, id, err); + pr_warn("failed to load module [%s]'s BTF object #%d: %s\n", + name, id, errstr(err)); goto err_out; } @@ -5832,7 +5926,7 @@ bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path) obj->btf_vmlinux_override = btf__parse(targ_btf_path, NULL); err = libbpf_get_error(obj->btf_vmlinux_override); if (err) { - pr_warn("failed to parse target BTF: %d\n", err); + pr_warn("failed to parse target BTF: %s\n", errstr(err)); return err; } } @@ -5892,8 +5986,8 @@ bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path) err = record_relo_core(prog, rec, insn_idx); if (err) { - pr_warn("prog '%s': relo #%d: failed to record relocation: %d\n", - prog->name, i, err); + pr_warn("prog '%s': relo #%d: failed to record relocation: %s\n", + prog->name, i, errstr(err)); goto out; } @@ -5902,15 +5996,15 @@ bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path) err = bpf_core_resolve_relo(prog, rec, i, obj->btf, cand_cache, &targ_res); if (err) { - pr_warn("prog '%s': relo #%d: failed to relocate: %d\n", - prog->name, i, err); + pr_warn("prog '%s': relo #%d: failed to relocate: %s\n", + prog->name, i, errstr(err)); goto out; } err = bpf_core_patch_insn(prog->name, insn, insn_idx, rec, i, &targ_res); if (err) { - pr_warn("prog '%s': relo #%d: failed to patch insn #%u: %d\n", - prog->name, i, insn_idx, err); + pr_warn("prog '%s': relo #%d: failed to patch insn #%u: %s\n", + prog->name, i, insn_idx, errstr(err)); goto out; } } @@ -6178,8 +6272,8 @@ reloc_prog_func_and_line_info(const struct bpf_object *obj, &main_prog->func_info_rec_size); if (err) { if (err != -ENOENT) { - pr_warn("prog '%s': error relocating .BTF.ext function info: %d\n", - prog->name, err); + pr_warn("prog '%s': error relocating .BTF.ext function info: %s\n", + prog->name, errstr(err)); return err; } if (main_prog->func_info) { @@ -6206,8 +6300,8 @@ line_info: &main_prog->line_info_rec_size); if (err) { if (err != -ENOENT) { - pr_warn("prog '%s': error relocating .BTF.ext line info: %d\n", - prog->name, err); + pr_warn("prog '%s': error relocating .BTF.ext line info: %s\n", + prog->name, errstr(err)); return err; } if (main_prog->line_info) { @@ -6971,8 +7065,8 @@ static int bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_pat if (obj->btf_ext) { err = bpf_object__relocate_core(obj, targ_btf_path); if (err) { - pr_warn("failed to perform CO-RE relocations: %d\n", - err); + pr_warn("failed to perform CO-RE relocations: %s\n", + errstr(err)); return err; } bpf_object__sort_relos(obj); @@ -7016,8 +7110,8 @@ static int bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_pat err = bpf_object__relocate_calls(obj, prog); if (err) { - pr_warn("prog '%s': failed to relocate calls: %d\n", - prog->name, err); + pr_warn("prog '%s': failed to relocate calls: %s\n", + prog->name, errstr(err)); return err; } @@ -7053,16 +7147,16 @@ static int bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_pat /* Process data relos for main programs */ err = bpf_object__relocate_data(obj, prog); if (err) { - pr_warn("prog '%s': failed to relocate data references: %d\n", - prog->name, err); + pr_warn("prog '%s': failed to relocate data references: %s\n", + prog->name, errstr(err)); return err; } /* Fix up .BTF.ext information, if necessary */ err = bpf_program_fixup_func_info(obj, prog); if (err) { - pr_warn("prog '%s': failed to perform .BTF.ext fix ups: %d\n", - prog->name, err); + pr_warn("prog '%s': failed to perform .BTF.ext fix ups: %s\n", + prog->name, errstr(err)); return err; } } @@ -7314,8 +7408,14 @@ static int libbpf_prepare_prog_load(struct bpf_program *prog, opts->prog_flags |= BPF_F_XDP_HAS_FRAGS; /* special check for usdt to use uprobe_multi link */ - if ((def & SEC_USDT) && kernel_supports(prog->obj, FEAT_UPROBE_MULTI_LINK)) + if ((def & SEC_USDT) && kernel_supports(prog->obj, FEAT_UPROBE_MULTI_LINK)) { + /* for BPF_TRACE_UPROBE_MULTI, user might want to query expected_attach_type + * in prog, and expected_attach_type we set in kernel is from opts, so we + * update both. + */ prog->expected_attach_type = BPF_TRACE_UPROBE_MULTI; + opts->expected_attach_type = BPF_TRACE_UPROBE_MULTI; + } if ((def & SEC_ATTACH_BTF) && !prog->attach_btf_id) { int btf_obj_fd = 0, btf_type_id = 0, err; @@ -7365,7 +7465,6 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog { LIBBPF_OPTS(bpf_prog_load_opts, load_attr); const char *prog_name = NULL; - char *cp, errmsg[STRERR_BUFSIZE]; size_t log_buf_size = 0; char *log_buf = NULL, *tmp; bool own_log_buf = true; @@ -7405,6 +7504,7 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog load_attr.attach_btf_id = prog->attach_btf_id; load_attr.kern_version = kern_version; load_attr.prog_ifindex = prog->prog_ifindex; + load_attr.expected_attach_type = prog->expected_attach_type; /* specify func_info/line_info only if kernel supports them */ if (obj->btf && btf__fd(obj->btf) >= 0 && kernel_supports(obj, FEAT_BTF_FUNC)) { @@ -7428,17 +7528,14 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog if (prog->sec_def && prog->sec_def->prog_prepare_load_fn) { err = prog->sec_def->prog_prepare_load_fn(prog, &load_attr, prog->sec_def->cookie); if (err < 0) { - pr_warn("prog '%s': failed to prepare load attributes: %d\n", - prog->name, err); + pr_warn("prog '%s': failed to prepare load attributes: %s\n", + prog->name, errstr(err)); return err; } insns = prog->insns; insns_cnt = prog->insns_cnt; } - /* allow prog_prepare_load_fn to change expected_attach_type */ - load_attr.expected_attach_type = prog->expected_attach_type; - if (obj->gen_loader) { bpf_gen__prog_load(obj->gen_loader, prog->type, prog->name, license, insns, insns_cnt, &load_attr, @@ -7496,9 +7593,8 @@ retry_load: continue; if (bpf_prog_bind_map(ret, map->fd, NULL)) { - cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); pr_warn("prog '%s': failed to bind map '%s': %s\n", - prog->name, map->real_name, cp); + prog->name, map->real_name, errstr(errno)); /* Don't fail hard if can't bind rodata. */ } } @@ -7528,8 +7624,7 @@ retry_load: /* post-process verifier log to improve error descriptions */ fixup_verifier_log(prog, log_buf, log_buf_size); - cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); - pr_warn("prog '%s': BPF program load failed: %s\n", prog->name, cp); + pr_warn("prog '%s': BPF program load failed: %s\n", prog->name, errstr(errno)); pr_perm_msg(ret); if (own_log_buf && log_buf && log_buf[0] != '\0') { @@ -7801,13 +7896,6 @@ bpf_object__load_progs(struct bpf_object *obj, int log_level) for (i = 0; i < obj->nr_programs; i++) { prog = &obj->programs[i]; - err = bpf_object__sanitize_prog(obj, prog); - if (err) - return err; - } - - for (i = 0; i < obj->nr_programs; i++) { - prog = &obj->programs[i]; if (prog_is_subprog(obj, prog)) continue; if (!prog->autoload) { @@ -7822,7 +7910,7 @@ bpf_object__load_progs(struct bpf_object *obj, int log_level) err = bpf_object_load_prog(obj, prog, prog->insns, prog->insns_cnt, obj->license, obj->kern_version, &prog->fd); if (err) { - pr_warn("prog '%s': failed to load: %d\n", prog->name, err); + pr_warn("prog '%s': failed to load: %s\n", prog->name, errstr(err)); return err; } } @@ -7831,6 +7919,21 @@ bpf_object__load_progs(struct bpf_object *obj, int log_level) return 0; } +static int bpf_object_prepare_progs(struct bpf_object *obj) +{ + struct bpf_program *prog; + size_t i; + int err; + + for (i = 0; i < obj->nr_programs; i++) { + prog = &obj->programs[i]; + err = bpf_object__sanitize_prog(obj, prog); + if (err) + return err; + } + return 0; +} + static const struct bpf_sec_def *find_sec_def(const char *sec_name); static int bpf_object_init_progs(struct bpf_object *obj, const struct bpf_object_open_opts *opts) @@ -7856,8 +7959,8 @@ static int bpf_object_init_progs(struct bpf_object *obj, const struct bpf_object if (prog->sec_def->prog_setup_fn) { err = prog->sec_def->prog_setup_fn(prog, prog->sec_def->cookie); if (err < 0) { - pr_warn("prog '%s': failed to initialize: %d\n", - prog->name, err); + pr_warn("prog '%s': failed to initialize: %s\n", + prog->name, errstr(err)); return err; } } @@ -7867,16 +7970,19 @@ static int bpf_object_init_progs(struct bpf_object *obj, const struct bpf_object } static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf, size_t obj_buf_sz, + const char *obj_name, const struct bpf_object_open_opts *opts) { - const char *obj_name, *kconfig, *btf_tmp_path, *token_path; + const char *kconfig, *btf_tmp_path, *token_path; struct bpf_object *obj; - char tmp_name[64]; int err; char *log_buf; size_t log_size; __u32 log_level; + if (obj_buf && !obj_name) + return ERR_PTR(-EINVAL); + if (elf_version(EV_CURRENT) == EV_NONE) { pr_warn("failed to init libelf for %s\n", path ? : "(mem buf)"); @@ -7886,16 +7992,12 @@ static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf, if (!OPTS_VALID(opts, bpf_object_open_opts)) return ERR_PTR(-EINVAL); - obj_name = OPTS_GET(opts, object_name, NULL); + obj_name = OPTS_GET(opts, object_name, NULL) ?: obj_name; if (obj_buf) { - if (!obj_name) { - snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx", - (unsigned long)obj_buf, - (unsigned long)obj_buf_sz); - obj_name = tmp_name; - } path = obj_name; pr_debug("loading object '%s' from buffer\n", obj_name); + } else { + pr_debug("loading object from %s\n", path); } log_buf = OPTS_GET(opts, kernel_log_buf, NULL); @@ -7955,7 +8057,6 @@ static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf, } err = bpf_object__elf_init(obj); - err = err ? : bpf_object__check_endianness(obj); err = err ? : bpf_object__elf_collect(obj); err = err ? : bpf_object__collect_externs(obj); err = err ? : bpf_object_fixup_btf(obj); @@ -7979,9 +8080,7 @@ bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts) if (!path) return libbpf_err_ptr(-EINVAL); - pr_debug("loading %s\n", path); - - return libbpf_ptr(bpf_object_open(path, NULL, 0, opts)); + return libbpf_ptr(bpf_object_open(path, NULL, 0, NULL, opts)); } struct bpf_object *bpf_object__open(const char *path) @@ -7993,10 +8092,15 @@ struct bpf_object * bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz, const struct bpf_object_open_opts *opts) { + char tmp_name[64]; + if (!obj_buf || obj_buf_sz == 0) return libbpf_err_ptr(-EINVAL); - return libbpf_ptr(bpf_object_open(NULL, obj_buf, obj_buf_sz, opts)); + /* create a (quite useless) default "name" for this memory buffer object */ + snprintf(tmp_name, sizeof(tmp_name), "%lx-%zx", (unsigned long)obj_buf, obj_buf_sz); + + return libbpf_ptr(bpf_object_open(NULL, obj_buf, obj_buf_sz, tmp_name, opts)); } static int bpf_object_unload(struct bpf_object *obj) @@ -8045,7 +8149,7 @@ static int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *ctx) f = fopen("/proc/kallsyms", "re"); if (!f) { err = -errno; - pr_warn("failed to open /proc/kallsyms: %d\n", err); + pr_warn("failed to open /proc/kallsyms: %s\n", errstr(err)); return err; } @@ -8406,11 +8510,13 @@ static int bpf_object__resolve_externs(struct bpf_object *obj, static void bpf_map_prepare_vdata(const struct bpf_map *map) { + const struct btf_type *type; struct bpf_struct_ops *st_ops; __u32 i; st_ops = map->st_ops; - for (i = 0; i < btf_vlen(st_ops->type); i++) { + type = btf__type_by_id(map->obj->btf, st_ops->type_id); + for (i = 0; i < btf_vlen(type); i++) { struct bpf_program *prog = st_ops->progs[i]; void *kern_data; int prog_fd; @@ -8444,20 +8550,45 @@ static int bpf_object_prepare_struct_ops(struct bpf_object *obj) return 0; } -static int bpf_object_load(struct bpf_object *obj, int extra_log_level, const char *target_btf_path) +static void bpf_object_unpin(struct bpf_object *obj) { - int err, i; + int i; - if (!obj) - return libbpf_err(-EINVAL); + /* unpin any maps that were auto-pinned during load */ + for (i = 0; i < obj->nr_maps; i++) + if (obj->maps[i].pinned && !obj->maps[i].reused) + bpf_map__unpin(&obj->maps[i], NULL); +} - if (obj->loaded) { - pr_warn("object '%s': load can't be attempted twice\n", obj->name); - return libbpf_err(-EINVAL); +static void bpf_object_post_load_cleanup(struct bpf_object *obj) +{ + int i; + + /* clean up fd_array */ + zfree(&obj->fd_array); + + /* clean up module BTFs */ + for (i = 0; i < obj->btf_module_cnt; i++) { + close(obj->btf_modules[i].fd); + btf__free(obj->btf_modules[i].btf); + free(obj->btf_modules[i].name); } + obj->btf_module_cnt = 0; + zfree(&obj->btf_modules); - if (obj->gen_loader) - bpf_gen__init(obj->gen_loader, extra_log_level, obj->nr_programs, obj->nr_maps); + /* clean up vmlinux BTF */ + btf__free(obj->btf_vmlinux); + obj->btf_vmlinux = NULL; +} + +static int bpf_object_prepare(struct bpf_object *obj, const char *target_btf_path) +{ + int err; + + if (obj->state >= OBJ_PREPARED) { + pr_warn("object '%s': prepare loading can't be attempted twice\n", obj->name); + return -EINVAL; + } err = bpf_object_prepare_token(obj); err = err ? : bpf_object__probe_loading(obj); @@ -8469,7 +8600,47 @@ static int bpf_object_load(struct bpf_object *obj, int extra_log_level, const ch err = err ? : bpf_object__relocate(obj, obj->btf_custom_path ? : target_btf_path); err = err ? : bpf_object__sanitize_and_load_btf(obj); err = err ? : bpf_object__create_maps(obj); - err = err ? : bpf_object__load_progs(obj, extra_log_level); + err = err ? : bpf_object_prepare_progs(obj); + + if (err) { + bpf_object_unpin(obj); + bpf_object_unload(obj); + obj->state = OBJ_LOADED; + return err; + } + + obj->state = OBJ_PREPARED; + return 0; +} + +static int bpf_object_load(struct bpf_object *obj, int extra_log_level, const char *target_btf_path) +{ + int err; + + if (!obj) + return libbpf_err(-EINVAL); + + if (obj->state >= OBJ_LOADED) { + pr_warn("object '%s': load can't be attempted twice\n", obj->name); + return libbpf_err(-EINVAL); + } + + /* Disallow kernel loading programs of non-native endianness but + * permit cross-endian creation of "light skeleton". + */ + if (obj->gen_loader) { + bpf_gen__init(obj->gen_loader, extra_log_level, obj->nr_programs, obj->nr_maps); + } else if (!is_native_endianness(obj)) { + pr_warn("object '%s': loading non-native endianness is unsupported\n", obj->name); + return libbpf_err(-LIBBPF_ERRNO__ENDIAN); + } + + if (obj->state < OBJ_PREPARED) { + err = bpf_object_prepare(obj, target_btf_path); + if (err) + return libbpf_err(err); + } + err = bpf_object__load_progs(obj, extra_log_level); err = err ? : bpf_object_init_prog_arrays(obj); err = err ? : bpf_object_prepare_struct_ops(obj); @@ -8481,36 +8652,22 @@ static int bpf_object_load(struct bpf_object *obj, int extra_log_level, const ch err = bpf_gen__finish(obj->gen_loader, obj->nr_programs, obj->nr_maps); } - /* clean up fd_array */ - zfree(&obj->fd_array); + bpf_object_post_load_cleanup(obj); + obj->state = OBJ_LOADED; /* doesn't matter if successfully or not */ - /* clean up module BTFs */ - for (i = 0; i < obj->btf_module_cnt; i++) { - close(obj->btf_modules[i].fd); - btf__free(obj->btf_modules[i].btf); - free(obj->btf_modules[i].name); + if (err) { + bpf_object_unpin(obj); + bpf_object_unload(obj); + pr_warn("failed to load object '%s'\n", obj->path); + return libbpf_err(err); } - free(obj->btf_modules); - - /* clean up vmlinux BTF */ - btf__free(obj->btf_vmlinux); - obj->btf_vmlinux = NULL; - - obj->loaded = true; /* doesn't matter if successfully or not */ - - if (err) - goto out; return 0; -out: - /* unpin any maps that were auto-pinned during load */ - for (i = 0; i < obj->nr_maps; i++) - if (obj->maps[i].pinned && !obj->maps[i].reused) - bpf_map__unpin(&obj->maps[i], NULL); +} - bpf_object_unload(obj); - pr_warn("failed to load object '%s'\n", obj->path); - return libbpf_err(err); +int bpf_object__prepare(struct bpf_object *obj) +{ + return libbpf_err(bpf_object_prepare(obj, NULL)); } int bpf_object__load(struct bpf_object *obj) @@ -8520,7 +8677,6 @@ int bpf_object__load(struct bpf_object *obj) static int make_parent_dir(const char *path) { - char *cp, errmsg[STRERR_BUFSIZE]; char *dname, *dir; int err = 0; @@ -8534,15 +8690,13 @@ static int make_parent_dir(const char *path) free(dname); if (err) { - cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); - pr_warn("failed to mkdir %s: %s\n", path, cp); + pr_warn("failed to mkdir %s: %s\n", path, errstr(err)); } return err; } static int check_path(const char *path) { - char *cp, errmsg[STRERR_BUFSIZE]; struct statfs st_fs; char *dname, *dir; int err = 0; @@ -8556,8 +8710,7 @@ static int check_path(const char *path) dir = dirname(dname); if (statfs(dir, &st_fs)) { - cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); - pr_warn("failed to statfs %s: %s\n", dir, cp); + pr_warn("failed to statfs %s: %s\n", dir, errstr(errno)); err = -errno; } free(dname); @@ -8572,7 +8725,6 @@ static int check_path(const char *path) int bpf_program__pin(struct bpf_program *prog, const char *path) { - char *cp, errmsg[STRERR_BUFSIZE]; int err; if (prog->fd < 0) { @@ -8590,8 +8742,7 @@ int bpf_program__pin(struct bpf_program *prog, const char *path) if (bpf_obj_pin(prog->fd, path)) { err = -errno; - cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); - pr_warn("prog '%s': failed to pin at '%s': %s\n", prog->name, path, cp); + pr_warn("prog '%s': failed to pin at '%s': %s\n", prog->name, path, errstr(err)); return libbpf_err(err); } @@ -8622,7 +8773,6 @@ int bpf_program__unpin(struct bpf_program *prog, const char *path) int bpf_map__pin(struct bpf_map *map, const char *path) { - char *cp, errmsg[STRERR_BUFSIZE]; int err; if (map == NULL) { @@ -8681,8 +8831,7 @@ int bpf_map__pin(struct bpf_map *map, const char *path) return 0; out_err: - cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); - pr_warn("failed to pin map: %s\n", cp); + pr_warn("failed to pin map: %s\n", errstr(err)); return libbpf_err(err); } @@ -8768,7 +8917,7 @@ int bpf_object__pin_maps(struct bpf_object *obj, const char *path) if (!obj) return libbpf_err(-ENOENT); - if (!obj->loaded) { + if (obj->state < OBJ_PREPARED) { pr_warn("object not yet loaded; load it first\n"); return libbpf_err(-ENOENT); } @@ -8847,7 +8996,7 @@ int bpf_object__pin_programs(struct bpf_object *obj, const char *path) if (!obj) return libbpf_err(-ENOENT); - if (!obj->loaded) { + if (obj->state < OBJ_LOADED) { pr_warn("object not yet loaded; load it first\n"); return libbpf_err(-ENOENT); } @@ -8966,6 +9115,13 @@ void bpf_object__close(struct bpf_object *obj) if (IS_ERR_OR_NULL(obj)) return; + /* + * if user called bpf_object__prepare() without ever getting to + * bpf_object__load(), we need to clean up stuff that is normally + * cleaned up at the end of loading step + */ + bpf_object_post_load_cleanup(obj); + usdt_manager_free(obj->usdt_man); obj->usdt_man = NULL; @@ -9017,6 +9173,11 @@ unsigned int bpf_object__kversion(const struct bpf_object *obj) return obj ? obj->kern_version : 0; } +int bpf_object__token_fd(const struct bpf_object *obj) +{ + return obj->token_fd ?: -1; +} + struct btf *bpf_object__btf(const struct bpf_object *obj) { return obj ? obj->btf : NULL; @@ -9029,7 +9190,7 @@ int bpf_object__btf_fd(const struct bpf_object *obj) int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version) { - if (obj->loaded) + if (obj->state >= OBJ_LOADED) return libbpf_err(-EINVAL); obj->kern_version = kern_version; @@ -9042,13 +9203,14 @@ int bpf_object__gen_loader(struct bpf_object *obj, struct gen_loader_opts *opts) struct bpf_gen *gen; if (!opts) - return -EFAULT; + return libbpf_err(-EFAULT); if (!OPTS_VALID(opts, gen_loader_opts)) - return -EINVAL; + return libbpf_err(-EINVAL); gen = calloc(sizeof(*gen), 1); if (!gen) - return -ENOMEM; + return libbpf_err(-ENOMEM); gen->opts = opts; + gen->swapped_endian = !is_native_endianness(obj); obj->gen_loader = gen; return 0; } @@ -9125,7 +9287,7 @@ bool bpf_program__autoload(const struct bpf_program *prog) int bpf_program__set_autoload(struct bpf_program *prog, bool autoload) { - if (prog->obj->loaded) + if (prog->obj->state >= OBJ_LOADED) return libbpf_err(-EINVAL); prog->autoload = autoload; @@ -9157,14 +9319,14 @@ int bpf_program__set_insns(struct bpf_program *prog, { struct bpf_insn *insns; - if (prog->obj->loaded) - return -EBUSY; + if (prog->obj->state >= OBJ_LOADED) + return libbpf_err(-EBUSY); insns = libbpf_reallocarray(prog->insns, new_insn_cnt, sizeof(*insns)); /* NULL is a valid return from reallocarray if the new count is zero */ if (!insns && new_insn_cnt) { pr_warn("prog '%s': failed to realloc prog code\n", prog->name); - return -ENOMEM; + return libbpf_err(-ENOMEM); } memcpy(insns, new_insns, new_insn_cnt * sizeof(*insns)); @@ -9200,7 +9362,7 @@ static int last_custom_sec_def_handler_id; int bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type) { - if (prog->obj->loaded) + if (prog->obj->state >= OBJ_LOADED) return libbpf_err(-EBUSY); /* if type is not changed, do nothing */ @@ -9231,7 +9393,7 @@ enum bpf_attach_type bpf_program__expected_attach_type(const struct bpf_program int bpf_program__set_expected_attach_type(struct bpf_program *prog, enum bpf_attach_type type) { - if (prog->obj->loaded) + if (prog->obj->state >= OBJ_LOADED) return libbpf_err(-EBUSY); prog->expected_attach_type = type; @@ -9245,7 +9407,7 @@ __u32 bpf_program__flags(const struct bpf_program *prog) int bpf_program__set_flags(struct bpf_program *prog, __u32 flags) { - if (prog->obj->loaded) + if (prog->obj->state >= OBJ_LOADED) return libbpf_err(-EBUSY); prog->prog_flags = flags; @@ -9259,7 +9421,7 @@ __u32 bpf_program__log_level(const struct bpf_program *prog) int bpf_program__set_log_level(struct bpf_program *prog, __u32 log_level) { - if (prog->obj->loaded) + if (prog->obj->state >= OBJ_LOADED) return libbpf_err(-EBUSY); prog->log_level = log_level; @@ -9275,17 +9437,41 @@ const char *bpf_program__log_buf(const struct bpf_program *prog, size_t *log_siz int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log_size) { if (log_size && !log_buf) - return -EINVAL; + return libbpf_err(-EINVAL); if (prog->log_size > UINT_MAX) - return -EINVAL; - if (prog->obj->loaded) - return -EBUSY; + return libbpf_err(-EINVAL); + if (prog->obj->state >= OBJ_LOADED) + return libbpf_err(-EBUSY); prog->log_buf = log_buf; prog->log_size = log_size; return 0; } +struct bpf_func_info *bpf_program__func_info(const struct bpf_program *prog) +{ + if (prog->func_info_rec_size != sizeof(struct bpf_func_info)) + return libbpf_err_ptr(-EOPNOTSUPP); + return prog->func_info; +} + +__u32 bpf_program__func_info_cnt(const struct bpf_program *prog) +{ + return prog->func_info_cnt; +} + +struct bpf_line_info *bpf_program__line_info(const struct bpf_program *prog) +{ + if (prog->line_info_rec_size != sizeof(struct bpf_line_info)) + return libbpf_err_ptr(-EOPNOTSUPP); + return prog->line_info; +} + +__u32 bpf_program__line_info_cnt(const struct bpf_program *prog) +{ + return prog->line_info_cnt; +} + #define SEC_DEF(sec_pfx, ptype, atype, flags, ...) { \ .sec = (char *)sec_pfx, \ .prog_type = BPF_PROG_TYPE_##ptype, \ @@ -9323,8 +9509,10 @@ static const struct bpf_sec_def section_defs[] = { SEC_DEF("kprobe.session+", KPROBE, BPF_TRACE_KPROBE_SESSION, SEC_NONE, attach_kprobe_session), SEC_DEF("uprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), SEC_DEF("uretprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), + SEC_DEF("uprobe.session+", KPROBE, BPF_TRACE_UPROBE_SESSION, SEC_NONE, attach_uprobe_multi), SEC_DEF("uprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi), SEC_DEF("uretprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi), + SEC_DEF("uprobe.session.s+", KPROBE, BPF_TRACE_UPROBE_SESSION, SEC_SLEEPABLE, attach_uprobe_multi), SEC_DEF("ksyscall+", KPROBE, 0, SEC_NONE, attach_ksyscall), SEC_DEF("kretsyscall+", KPROBE, 0, SEC_NONE, attach_ksyscall), SEC_DEF("usdt+", KPROBE, 0, SEC_USDT, attach_usdt), @@ -9673,6 +9861,7 @@ static struct bpf_map *find_struct_ops_map_by_offset(struct bpf_object *obj, static int bpf_object__collect_st_ops_relos(struct bpf_object *obj, Elf64_Shdr *shdr, Elf_Data *data) { + const struct btf_type *type; const struct btf_member *member; struct bpf_struct_ops *st_ops; struct bpf_program *prog; @@ -9732,13 +9921,14 @@ static int bpf_object__collect_st_ops_relos(struct bpf_object *obj, } insn_idx = sym->st_value / BPF_INSN_SZ; - member = find_member_by_offset(st_ops->type, moff * 8); + type = btf__type_by_id(btf, st_ops->type_id); + member = find_member_by_offset(type, moff * 8); if (!member) { pr_warn("struct_ops reloc %s: cannot find member at moff %u\n", map->name, moff); return -EINVAL; } - member_idx = member - btf_members(st_ops->type); + member_idx = member - btf_members(type); name = btf__name_by_offset(btf, member->name_off); if (!resolve_func_ptr(btf, member->type, NULL)) { @@ -9851,7 +10041,7 @@ int libbpf_find_vmlinux_btf_id(const char *name, return libbpf_err(err); } -static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd) +static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd, int token_fd) { struct bpf_prog_info info; __u32 info_len = sizeof(info); @@ -9861,8 +10051,8 @@ static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd) memset(&info, 0, info_len); err = bpf_prog_get_info_by_fd(attach_prog_fd, &info, &info_len); if (err) { - pr_warn("failed bpf_prog_get_info_by_fd for FD %d: %d\n", - attach_prog_fd, err); + pr_warn("failed bpf_prog_get_info_by_fd for FD %d: %s\n", + attach_prog_fd, errstr(err)); return err; } @@ -9871,10 +10061,10 @@ static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd) pr_warn("The target program doesn't have BTF\n"); goto out; } - btf = btf__load_from_kernel_by_id(info.btf_id); + btf = btf_load_from_kernel(info.btf_id, NULL, token_fd); err = libbpf_get_error(btf); if (err) { - pr_warn("Failed to get BTF %d of the program: %d\n", info.btf_id, err); + pr_warn("Failed to get BTF %d of the program: %s\n", info.btf_id, errstr(err)); goto out; } err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); @@ -9954,10 +10144,10 @@ static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attac pr_warn("prog '%s': attach program FD is not set\n", prog->name); return -EINVAL; } - err = libbpf_find_prog_btf_id(attach_name, attach_prog_fd); + err = libbpf_find_prog_btf_id(attach_name, attach_prog_fd, prog->obj->token_fd); if (err < 0) { - pr_warn("prog '%s': failed to find BPF program (FD %d) BTF ID for '%s': %d\n", - prog->name, attach_prog_fd, attach_name, err); + pr_warn("prog '%s': failed to find BPF program (FD %d) BTF ID for '%s': %s\n", + prog->name, attach_prog_fd, attach_name, errstr(err)); return err; } *btf_obj_fd = 0; @@ -9976,8 +10166,8 @@ static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attac btf_type_id); } if (err) { - pr_warn("prog '%s': failed to find kernel BTF type ID of '%s': %d\n", - prog->name, attach_name, err); + pr_warn("prog '%s': failed to find kernel BTF type ID of '%s': %s\n", + prog->name, attach_name, errstr(err)); return err; } return 0; @@ -10191,7 +10381,7 @@ static int map_btf_datasec_resize(struct bpf_map *map, __u32 size) int bpf_map__set_value_size(struct bpf_map *map, __u32 size) { - if (map->obj->loaded || map->reused) + if (map_is_created(map)) return libbpf_err(-EBUSY); if (map->mmaped) { @@ -10199,20 +10389,20 @@ int bpf_map__set_value_size(struct bpf_map *map, __u32 size) int err; if (map->def.type != BPF_MAP_TYPE_ARRAY) - return -EOPNOTSUPP; + return libbpf_err(-EOPNOTSUPP); mmap_old_sz = bpf_map_mmap_sz(map); mmap_new_sz = array_map_mmap_sz(size, map->def.max_entries); err = bpf_map_mmap_resize(map, mmap_old_sz, mmap_new_sz); if (err) { - pr_warn("map '%s': failed to resize memory-mapped region: %d\n", - bpf_map__name(map), err); - return err; + pr_warn("map '%s': failed to resize memory-mapped region: %s\n", + bpf_map__name(map), errstr(err)); + return libbpf_err(err); } err = map_btf_datasec_resize(map, size); if (err && err != -ENOENT) { - pr_warn("map '%s': failed to adjust resized BTF, clearing BTF key/value info: %d\n", - bpf_map__name(map), err); + pr_warn("map '%s': failed to adjust resized BTF, clearing BTF key/value info: %s\n", + bpf_map__name(map), errstr(err)); map->btf_value_type_id = 0; map->btf_key_type_id = 0; } @@ -10237,7 +10427,7 @@ int bpf_map__set_initial_value(struct bpf_map *map, { size_t actual_sz; - if (map->obj->loaded || map->reused) + if (map_is_created(map)) return libbpf_err(-EBUSY); if (!map->mmaped || map->libbpf_type == LIBBPF_MAP_KCONFIG) @@ -10336,7 +10526,7 @@ __bpf_map__iter(const struct bpf_map *m, const struct bpf_object *obj, int i) struct bpf_map * bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *prev) { - if (prev == NULL) + if (prev == NULL && obj != NULL) return obj->maps; return __bpf_map__iter(prev, obj, 1); @@ -10345,7 +10535,7 @@ bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *prev) struct bpf_map * bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *next) { - if (next == NULL) { + if (next == NULL && obj != NULL) { if (!obj->nr_maps) return NULL; return obj->maps + obj->nr_maps - 1; @@ -10703,7 +10893,6 @@ static void bpf_link_perf_dealloc(struct bpf_link *link) struct bpf_link *bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd, const struct bpf_perf_event_opts *opts) { - char errmsg[STRERR_BUFSIZE]; struct bpf_link_perf *link; int prog_fd, link_fd = -1, err; bool force_ioctl_attach; @@ -10738,9 +10927,8 @@ struct bpf_link *bpf_program__attach_perf_event_opts(const struct bpf_program *p link_fd = bpf_link_create(prog_fd, pfd, BPF_PERF_EVENT, &link_opts); if (link_fd < 0) { err = -errno; - pr_warn("prog '%s': failed to create BPF link for perf_event FD %d: %d (%s)\n", - prog->name, pfd, - err, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + pr_warn("prog '%s': failed to create BPF link for perf_event FD %d: %s\n", + prog->name, pfd, errstr(err)); goto err_out; } link->link.fd = link_fd; @@ -10754,7 +10942,7 @@ struct bpf_link *bpf_program__attach_perf_event_opts(const struct bpf_program *p if (ioctl(pfd, PERF_EVENT_IOC_SET_BPF, prog_fd) < 0) { err = -errno; pr_warn("prog '%s': failed to attach to perf_event FD %d: %s\n", - prog->name, pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + prog->name, pfd, errstr(err)); if (err == -EPROTO) pr_warn("prog '%s': try add PERF_SAMPLE_CALLCHAIN to or remove exclude_callchain_[kernel|user] from pfd %d\n", prog->name, pfd); @@ -10765,7 +10953,7 @@ struct bpf_link *bpf_program__attach_perf_event_opts(const struct bpf_program *p if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { err = -errno; pr_warn("prog '%s': failed to enable perf_event FD %d: %s\n", - prog->name, pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + prog->name, pfd, errstr(err)); goto err_out; } @@ -10789,22 +10977,19 @@ struct bpf_link *bpf_program__attach_perf_event(const struct bpf_program *prog, */ static int parse_uint_from_file(const char *file, const char *fmt) { - char buf[STRERR_BUFSIZE]; int err, ret; FILE *f; f = fopen(file, "re"); if (!f) { err = -errno; - pr_debug("failed to open '%s': %s\n", file, - libbpf_strerror_r(err, buf, sizeof(buf))); + pr_debug("failed to open '%s': %s\n", file, errstr(err)); return err; } err = fscanf(f, fmt, &ret); if (err != 1) { err = err == EOF ? -EIO : -errno; - pr_debug("failed to parse '%s': %s\n", file, - libbpf_strerror_r(err, buf, sizeof(buf))); + pr_debug("failed to parse '%s': %s\n", file, errstr(err)); fclose(f); return err; } @@ -10848,7 +11033,6 @@ static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, { const size_t attr_sz = sizeof(struct perf_event_attr); struct perf_event_attr attr; - char errmsg[STRERR_BUFSIZE]; int type, pfd; if ((__u64)ref_ctr_off >= (1ULL << PERF_UPROBE_REF_CTR_OFFSET_BITS)) @@ -10861,7 +11045,7 @@ static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, if (type < 0) { pr_warn("failed to determine %s perf type: %s\n", uprobe ? "uprobe" : "kprobe", - libbpf_strerror_r(type, errmsg, sizeof(errmsg))); + errstr(type)); return type; } if (retprobe) { @@ -10871,7 +11055,7 @@ static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, if (bit < 0) { pr_warn("failed to determine %s retprobe bit: %s\n", uprobe ? "uprobe" : "kprobe", - libbpf_strerror_r(bit, errmsg, sizeof(errmsg))); + errstr(bit)); return bit; } attr.config |= 1 << bit; @@ -10954,16 +11138,16 @@ static const char *tracefs_available_filter_functions_addrs(void) : TRACEFS"/available_filter_functions_addrs"; } -static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz, - const char *kfunc_name, size_t offset) +static void gen_probe_legacy_event_name(char *buf, size_t buf_sz, + const char *name, size_t offset) { static int index = 0; int i; - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset, - __sync_fetch_and_add(&index, 1)); + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), + __sync_fetch_and_add(&index, 1), name, offset); - /* sanitize binary_path in the probe name */ + /* sanitize name in the probe name */ for (i = 0; buf[i]; i++) { if (!isalnum(buf[i])) buf[i] = '_'; @@ -11000,14 +11184,13 @@ static int perf_event_kprobe_open_legacy(const char *probe_name, bool retprobe, { const size_t attr_sz = sizeof(struct perf_event_attr); struct perf_event_attr attr; - char errmsg[STRERR_BUFSIZE]; int type, pfd, err; err = add_kprobe_event_legacy(probe_name, retprobe, kfunc_name, offset); if (err < 0) { pr_warn("failed to add legacy kprobe event for '%s+0x%zx': %s\n", kfunc_name, offset, - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); return err; } type = determine_kprobe_perf_type_legacy(probe_name, retprobe); @@ -11015,7 +11198,7 @@ static int perf_event_kprobe_open_legacy(const char *probe_name, bool retprobe, err = type; pr_warn("failed to determine legacy kprobe event id for '%s+0x%zx': %s\n", kfunc_name, offset, - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); goto err_clean_legacy; } @@ -11031,7 +11214,7 @@ static int perf_event_kprobe_open_legacy(const char *probe_name, bool retprobe, if (pfd < 0) { err = -errno; pr_warn("legacy kprobe perf_event_open() failed: %s\n", - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); goto err_clean_legacy; } return pfd; @@ -11089,9 +11272,9 @@ int probe_kern_syscall_wrapper(int token_fd) return pfd >= 0 ? 1 : 0; } else { /* legacy mode */ - char probe_name[128]; + char probe_name[MAX_EVENT_NAME_LEN]; - gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); + gen_probe_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); if (add_kprobe_event_legacy(probe_name, false, syscall_name, 0) < 0) return 0; @@ -11107,7 +11290,6 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, { DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, pe_opts); enum probe_attach_mode attach_mode; - char errmsg[STRERR_BUFSIZE]; char *legacy_probe = NULL; struct bpf_link *link; size_t offset; @@ -11148,10 +11330,10 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, func_name, offset, -1 /* pid */, 0 /* ref_ctr_off */); } else { - char probe_name[256]; + char probe_name[MAX_EVENT_NAME_LEN]; - gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), - func_name, offset); + gen_probe_legacy_event_name(probe_name, sizeof(probe_name), + func_name, offset); legacy_probe = strdup(probe_name); if (!legacy_probe) @@ -11165,7 +11347,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, pr_warn("prog '%s': failed to create %s '%s+0x%zx' perf event: %s\n", prog->name, retprobe ? "kretprobe" : "kprobe", func_name, offset, - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); goto err_out; } link = bpf_program__attach_perf_event_opts(prog, pfd, &pe_opts); @@ -11175,7 +11357,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, pr_warn("prog '%s': failed to attach to %s '%s+0x%zx': %s\n", prog->name, retprobe ? "kretprobe" : "kprobe", func_name, offset, - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); goto err_clean_legacy; } if (legacy) { @@ -11287,9 +11469,33 @@ static int avail_kallsyms_cb(unsigned long long sym_addr, char sym_type, struct kprobe_multi_resolve *res = data->res; int err; - if (!bsearch(&sym_name, data->syms, data->cnt, sizeof(*data->syms), avail_func_cmp)) + if (!glob_match(sym_name, res->pattern)) return 0; + if (!bsearch(&sym_name, data->syms, data->cnt, sizeof(*data->syms), avail_func_cmp)) { + /* Some versions of kernel strip out .llvm.<hash> suffix from + * function names reported in available_filter_functions, but + * don't do so for kallsyms. While this is clearly a kernel + * bug (fixed by [0]) we try to accommodate that in libbpf to + * make multi-kprobe usability a bit better: if no match is + * found, we will strip .llvm. suffix and try one more time. + * + * [0] fb6a421fb615 ("kallsyms: Match symbols exactly with CONFIG_LTO_CLANG") + */ + char sym_trim[256], *psym_trim = sym_trim, *sym_sfx; + + if (!(sym_sfx = strstr(sym_name, ".llvm."))) + return 0; + + /* psym_trim vs sym_trim dance is done to avoid pointer vs array + * coercion differences and get proper `const char **` pointer + * which avail_func_cmp() expects + */ + snprintf(sym_trim, sizeof(sym_trim), "%.*s", (int)(sym_sfx - sym_name), sym_name); + if (!bsearch(&psym_trim, data->syms, data->cnt, sizeof(*data->syms), avail_func_cmp)) + return 0; + } + err = libbpf_ensure_mem((void **)&res->addrs, &res->cap, sizeof(*res->addrs), res->cnt + 1); if (err) return err; @@ -11311,7 +11517,7 @@ static int libbpf_available_kallsyms_parse(struct kprobe_multi_resolve *res) f = fopen(available_functions_file, "re"); if (!f) { err = -errno; - pr_warn("failed to open %s: %d\n", available_functions_file, err); + pr_warn("failed to open %s: %s\n", available_functions_file, errstr(err)); return err; } @@ -11386,7 +11592,7 @@ static int libbpf_available_kprobes_parse(struct kprobe_multi_resolve *res) f = fopen(available_path, "re"); if (!f) { err = -errno; - pr_warn("failed to open %s: %d\n", available_path, err); + pr_warn("failed to open %s: %s\n", available_path, errstr(err)); return err; } @@ -11432,10 +11638,9 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, }; enum bpf_attach_type attach_type; struct bpf_link *link = NULL; - char errmsg[STRERR_BUFSIZE]; const unsigned long *addrs; int err, link_fd, prog_fd; - bool retprobe, session; + bool retprobe, session, unique_match; const __u64 *cookies; const char **syms; size_t cnt; @@ -11454,6 +11659,7 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, addrs = OPTS_GET(opts, addrs, false); cnt = OPTS_GET(opts, cnt, false); cookies = OPTS_GET(opts, cookies, false); + unique_match = OPTS_GET(opts, unique_match, false); if (!pattern && !addrs && !syms) return libbpf_err_ptr(-EINVAL); @@ -11461,6 +11667,8 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, return libbpf_err_ptr(-EINVAL); if (!pattern && !cnt) return libbpf_err_ptr(-EINVAL); + if (!pattern && unique_match) + return libbpf_err_ptr(-EINVAL); if (addrs && syms) return libbpf_err_ptr(-EINVAL); @@ -11471,6 +11679,14 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, err = libbpf_available_kallsyms_parse(&res); if (err) goto error; + + if (unique_match && res.cnt != 1) { + pr_warn("prog '%s': failed to find a unique match for '%s' (%zu matches)\n", + prog->name, pattern, res.cnt); + err = -EINVAL; + goto error; + } + addrs = res.addrs; cnt = res.cnt; } @@ -11500,7 +11716,7 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, if (link_fd < 0) { err = -errno; pr_warn("prog '%s': failed to attach: %s\n", - prog->name, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + prog->name, errstr(err)); goto error; } link->fd = link_fd; @@ -11644,7 +11860,9 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru ret = 0; break; case 3: - opts.retprobe = strcmp(probe_type, "uretprobe.multi") == 0; + opts.session = str_has_pfx(probe_type, "uprobe.session"); + opts.retprobe = str_has_pfx(probe_type, "uretprobe.multi"); + *link = bpf_program__attach_uprobe_multi(prog, -1, binary_path, func_name, &opts); ret = libbpf_get_error(*link); break; @@ -11659,20 +11877,6 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru return ret; } -static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz, - const char *binary_path, uint64_t offset) -{ - int i; - - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), binary_path, (size_t)offset); - - /* sanitize binary_path in the probe name */ - for (i = 0; buf[i]; i++) { - if (!isalnum(buf[i])) - buf[i] = '_'; - } -} - static inline int add_uprobe_event_legacy(const char *probe_name, bool retprobe, const char *binary_path, size_t offset) { @@ -11707,15 +11911,15 @@ static int perf_event_uprobe_open_legacy(const char *probe_name, bool retprobe, err = add_uprobe_event_legacy(probe_name, retprobe, binary_path, offset); if (err < 0) { - pr_warn("failed to add legacy uprobe event for %s:0x%zx: %d\n", - binary_path, (size_t)offset, err); + pr_warn("failed to add legacy uprobe event for %s:0x%zx: %s\n", + binary_path, (size_t)offset, errstr(err)); return err; } type = determine_uprobe_perf_type_legacy(probe_name, retprobe); if (type < 0) { err = type; - pr_warn("failed to determine legacy uprobe event id for %s:0x%zx: %d\n", - binary_path, offset, err); + pr_warn("failed to determine legacy uprobe event id for %s:0x%zx: %s\n", + binary_path, offset, errstr(err)); goto err_clean_legacy; } @@ -11730,7 +11934,7 @@ static int perf_event_uprobe_open_legacy(const char *probe_name, bool retprobe, -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); if (pfd < 0) { err = -errno; - pr_warn("legacy uprobe perf_event_open() failed: %d\n", err); + pr_warn("legacy uprobe perf_event_open() failed: %s\n", errstr(err)); goto err_clean_legacy; } return pfd; @@ -11893,10 +12097,11 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, const unsigned long *ref_ctr_offsets = NULL, *offsets = NULL; LIBBPF_OPTS(bpf_link_create_opts, lopts); unsigned long *resolved_offsets = NULL; + enum bpf_attach_type attach_type; int err = 0, link_fd, prog_fd; struct bpf_link *link = NULL; - char errmsg[STRERR_BUFSIZE]; char full_path[PATH_MAX]; + bool retprobe, session; const __u64 *cookies; const char **syms; size_t cnt; @@ -11916,6 +12121,8 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, ref_ctr_offsets = OPTS_GET(opts, ref_ctr_offsets, NULL); cookies = OPTS_GET(opts, cookies, NULL); cnt = OPTS_GET(opts, cnt, 0); + retprobe = OPTS_GET(opts, retprobe, false); + session = OPTS_GET(opts, session, false); /* * User can specify 2 mutually exclusive set of inputs: @@ -11944,12 +12151,15 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, return libbpf_err_ptr(-EINVAL); } + if (retprobe && session) + return libbpf_err_ptr(-EINVAL); + if (func_pattern) { if (!strchr(path, '/')) { err = resolve_full_path(path, full_path, sizeof(full_path)); if (err) { - pr_warn("prog '%s': failed to resolve full path for '%s': %d\n", - prog->name, path, err); + pr_warn("prog '%s': failed to resolve full path for '%s': %s\n", + prog->name, path, errstr(err)); return libbpf_err_ptr(err); } path = full_path; @@ -11967,12 +12177,14 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, offsets = resolved_offsets; } + attach_type = session ? BPF_TRACE_UPROBE_SESSION : BPF_TRACE_UPROBE_MULTI; + lopts.uprobe_multi.path = path; lopts.uprobe_multi.offsets = offsets; lopts.uprobe_multi.ref_ctr_offsets = ref_ctr_offsets; lopts.uprobe_multi.cookies = cookies; lopts.uprobe_multi.cnt = cnt; - lopts.uprobe_multi.flags = OPTS_GET(opts, retprobe, false) ? BPF_F_UPROBE_MULTI_RETURN : 0; + lopts.uprobe_multi.flags = retprobe ? BPF_F_UPROBE_MULTI_RETURN : 0; if (pid == 0) pid = getpid(); @@ -11986,11 +12198,11 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, } link->detach = &bpf_link__detach_fd; - link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_UPROBE_MULTI, &lopts); + link_fd = bpf_link_create(prog_fd, 0, attach_type, &lopts); if (link_fd < 0) { err = -errno; pr_warn("prog '%s': failed to attach multi-uprobe: %s\n", - prog->name, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + prog->name, errstr(err)); goto error; } link->fd = link_fd; @@ -12009,7 +12221,7 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, const struct bpf_uprobe_opts *opts) { const char *archive_path = NULL, *archive_sep = NULL; - char errmsg[STRERR_BUFSIZE], *legacy_probe = NULL; + char *legacy_probe = NULL; DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, pe_opts); enum probe_attach_mode attach_mode; char full_path[PATH_MAX]; @@ -12041,8 +12253,8 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, } else if (!strchr(binary_path, '/')) { err = resolve_full_path(binary_path, full_path, sizeof(full_path)); if (err) { - pr_warn("prog '%s': failed to resolve full path for '%s': %d\n", - prog->name, binary_path, err); + pr_warn("prog '%s': failed to resolve full path for '%s': %s\n", + prog->name, binary_path, errstr(err)); return libbpf_err_ptr(err); } binary_path = full_path; @@ -12088,13 +12300,14 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, pfd = perf_event_open_probe(true /* uprobe */, retprobe, binary_path, func_offset, pid, ref_ctr_off); } else { - char probe_name[PATH_MAX + 64]; + char probe_name[MAX_EVENT_NAME_LEN]; if (ref_ctr_off) return libbpf_err_ptr(-EINVAL); - gen_uprobe_legacy_event_name(probe_name, sizeof(probe_name), - binary_path, func_offset); + gen_probe_legacy_event_name(probe_name, sizeof(probe_name), + strrchr(binary_path, '/') ? : binary_path, + func_offset); legacy_probe = strdup(probe_name); if (!legacy_probe) @@ -12108,7 +12321,7 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, pr_warn("prog '%s': failed to create %s '%s:0x%zx' perf event: %s\n", prog->name, retprobe ? "uretprobe" : "uprobe", binary_path, func_offset, - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); goto err_out; } @@ -12119,7 +12332,7 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, pr_warn("prog '%s': failed to attach to %s '%s:0x%zx': %s\n", prog->name, retprobe ? "uretprobe" : "uprobe", binary_path, func_offset, - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); goto err_clean_legacy; } if (legacy) { @@ -12240,8 +12453,8 @@ struct bpf_link *bpf_program__attach_usdt(const struct bpf_program *prog, if (!strchr(binary_path, '/')) { err = resolve_full_path(binary_path, resolved_path, sizeof(resolved_path)); if (err) { - pr_warn("prog '%s': failed to resolve full path for '%s': %d\n", - prog->name, binary_path, err); + pr_warn("prog '%s': failed to resolve full path for '%s': %s\n", + prog->name, binary_path, errstr(err)); return libbpf_err_ptr(err); } binary_path = resolved_path; @@ -12319,14 +12532,13 @@ static int perf_event_open_tracepoint(const char *tp_category, { const size_t attr_sz = sizeof(struct perf_event_attr); struct perf_event_attr attr; - char errmsg[STRERR_BUFSIZE]; int tp_id, pfd, err; tp_id = determine_tracepoint_id(tp_category, tp_name); if (tp_id < 0) { pr_warn("failed to determine tracepoint '%s/%s' perf event ID: %s\n", tp_category, tp_name, - libbpf_strerror_r(tp_id, errmsg, sizeof(errmsg))); + errstr(tp_id)); return tp_id; } @@ -12341,7 +12553,7 @@ static int perf_event_open_tracepoint(const char *tp_category, err = -errno; pr_warn("tracepoint '%s/%s' perf_event_open() failed: %s\n", tp_category, tp_name, - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); return err; } return pfd; @@ -12353,7 +12565,6 @@ struct bpf_link *bpf_program__attach_tracepoint_opts(const struct bpf_program *p const struct bpf_tracepoint_opts *opts) { DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, pe_opts); - char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; int pfd, err; @@ -12366,7 +12577,7 @@ struct bpf_link *bpf_program__attach_tracepoint_opts(const struct bpf_program *p if (pfd < 0) { pr_warn("prog '%s': failed to create tracepoint '%s/%s' perf event: %s\n", prog->name, tp_category, tp_name, - libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); + errstr(pfd)); return libbpf_err_ptr(pfd); } link = bpf_program__attach_perf_event_opts(prog, pfd, &pe_opts); @@ -12375,7 +12586,7 @@ struct bpf_link *bpf_program__attach_tracepoint_opts(const struct bpf_program *p close(pfd); pr_warn("prog '%s': failed to attach to tracepoint '%s/%s': %s\n", prog->name, tp_category, tp_name, - libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + errstr(err)); return libbpf_err_ptr(err); } return link; @@ -12426,7 +12637,6 @@ bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog, struct bpf_raw_tracepoint_opts *opts) { LIBBPF_OPTS(bpf_raw_tp_opts, raw_opts); - char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; int prog_fd, pfd; @@ -12451,7 +12661,7 @@ bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog, pfd = -errno; free(link); pr_warn("prog '%s': failed to attach to raw tracepoint '%s': %s\n", - prog->name, tp_name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); + prog->name, tp_name, errstr(pfd)); return libbpf_err_ptr(pfd); } link->fd = pfd; @@ -12510,7 +12720,6 @@ static struct bpf_link *bpf_program__attach_btf_id(const struct bpf_program *pro const struct bpf_trace_opts *opts) { LIBBPF_OPTS(bpf_link_create_opts, link_opts); - char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; int prog_fd, pfd; @@ -12535,7 +12744,7 @@ static struct bpf_link *bpf_program__attach_btf_id(const struct bpf_program *pro pfd = -errno; free(link); pr_warn("prog '%s': failed to attach: %s\n", - prog->name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); + prog->name, errstr(pfd)); return libbpf_err_ptr(pfd); } link->fd = pfd; @@ -12576,7 +12785,6 @@ bpf_program_attach_fd(const struct bpf_program *prog, const struct bpf_link_create_opts *opts) { enum bpf_attach_type attach_type; - char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; int prog_fd, link_fd; @@ -12598,7 +12806,7 @@ bpf_program_attach_fd(const struct bpf_program *prog, free(link); pr_warn("prog '%s': failed to attach to %s: %s\n", prog->name, target_name, - libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); + errstr(link_fd)); return libbpf_err_ptr(link_fd); } link->fd = link_fd; @@ -12711,7 +12919,7 @@ struct bpf_link *bpf_program__attach_freplace(const struct bpf_program *prog, } if (prog->type != BPF_PROG_TYPE_EXT) { - pr_warn("prog '%s': only BPF_PROG_TYPE_EXT can attach as freplace", + pr_warn("prog '%s': only BPF_PROG_TYPE_EXT can attach as freplace\n", prog->name); return libbpf_err_ptr(-EINVAL); } @@ -12719,7 +12927,7 @@ struct bpf_link *bpf_program__attach_freplace(const struct bpf_program *prog, if (target_fd) { LIBBPF_OPTS(bpf_link_create_opts, target_opts); - btf_id = libbpf_find_prog_btf_id(attach_func_name, target_fd); + btf_id = libbpf_find_prog_btf_id(attach_func_name, target_fd, prog->obj->token_fd); if (btf_id < 0) return libbpf_err_ptr(btf_id); @@ -12740,7 +12948,6 @@ bpf_program__attach_iter(const struct bpf_program *prog, const struct bpf_iter_attach_opts *opts) { DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_create_opts); - char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; int prog_fd, link_fd; __u32 target_fd = 0; @@ -12768,7 +12975,7 @@ bpf_program__attach_iter(const struct bpf_program *prog, link_fd = -errno; free(link); pr_warn("prog '%s': failed to attach to iterator: %s\n", - prog->name, libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); + prog->name, errstr(link_fd)); return libbpf_err_ptr(link_fd); } link->fd = link_fd; @@ -12810,12 +13017,10 @@ struct bpf_link *bpf_program__attach_netfilter(const struct bpf_program *prog, link_fd = bpf_link_create(prog_fd, 0, BPF_NETFILTER, &lopts); if (link_fd < 0) { - char errmsg[STRERR_BUFSIZE]; - link_fd = -errno; free(link); pr_warn("prog '%s': failed to attach to netfilter: %s\n", - prog->name, libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); + prog->name, errstr(link_fd)); return libbpf_err_ptr(link_fd); } link->fd = link_fd; @@ -12877,8 +13082,10 @@ struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) __u32 zero = 0; int err, fd; - if (!bpf_map__is_struct_ops(map)) + if (!bpf_map__is_struct_ops(map)) { + pr_warn("map '%s': can't attach non-struct_ops map\n", map->name); return libbpf_err_ptr(-EINVAL); + } if (map->fd < 0) { pr_warn("map '%s': can't attach BPF map without FD (was it created?)\n", map->name); @@ -12932,17 +13139,17 @@ int bpf_link__update_map(struct bpf_link *link, const struct bpf_map *map) int err; if (!bpf_map__is_struct_ops(map)) - return -EINVAL; + return libbpf_err(-EINVAL); if (map->fd < 0) { pr_warn("map '%s': can't use BPF map without FD (was it created?)\n", map->name); - return -EINVAL; + return libbpf_err(-EINVAL); } st_ops_link = container_of(link, struct bpf_link_struct_ops, link); /* Ensure the type of a link is correct */ if (st_ops_link->map_fd < 0) - return -EINVAL; + return libbpf_err(-EINVAL); err = bpf_map_update_elem(map->fd, &zero, map->st_ops->kern_vdata, 0); /* It can be EBUSY if the map has been used to create or @@ -13098,7 +13305,6 @@ perf_buffer__open_cpu_buf(struct perf_buffer *pb, struct perf_event_attr *attr, int cpu, int map_key) { struct perf_cpu_buf *cpu_buf; - char msg[STRERR_BUFSIZE]; int err; cpu_buf = calloc(1, sizeof(*cpu_buf)); @@ -13114,7 +13320,7 @@ perf_buffer__open_cpu_buf(struct perf_buffer *pb, struct perf_event_attr *attr, if (cpu_buf->fd < 0) { err = -errno; pr_warn("failed to open perf buffer event on cpu #%d: %s\n", - cpu, libbpf_strerror_r(err, msg, sizeof(msg))); + cpu, errstr(err)); goto error; } @@ -13125,14 +13331,14 @@ perf_buffer__open_cpu_buf(struct perf_buffer *pb, struct perf_event_attr *attr, cpu_buf->base = NULL; err = -errno; pr_warn("failed to mmap perf buffer on cpu #%d: %s\n", - cpu, libbpf_strerror_r(err, msg, sizeof(msg))); + cpu, errstr(err)); goto error; } if (ioctl(cpu_buf->fd, PERF_EVENT_IOC_ENABLE, 0) < 0) { err = -errno; pr_warn("failed to enable perf buffer event on cpu #%d: %s\n", - cpu, libbpf_strerror_r(err, msg, sizeof(msg))); + cpu, errstr(err)); goto error; } @@ -13169,7 +13375,6 @@ struct perf_buffer *perf_buffer__new(int map_fd, size_t page_cnt, attr.config = PERF_COUNT_SW_BPF_OUTPUT; attr.type = PERF_TYPE_SOFTWARE; attr.sample_type = PERF_SAMPLE_RAW; - attr.sample_period = sample_period; attr.wakeup_events = sample_period; p.attr = &attr; @@ -13208,7 +13413,6 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, { const char *online_cpus_file = "/sys/devices/system/cpu/online"; struct bpf_map_info map; - char msg[STRERR_BUFSIZE]; struct perf_buffer *pb; bool *online = NULL; __u32 map_info_len; @@ -13231,7 +13435,7 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, */ if (err != -EINVAL) { pr_warn("failed to get map info for map FD %d: %s\n", - map_fd, libbpf_strerror_r(err, msg, sizeof(msg))); + map_fd, errstr(err)); return ERR_PTR(err); } pr_debug("failed to get map info for FD %d; API not supported? Ignoring...\n", @@ -13261,7 +13465,7 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, if (pb->epoll_fd < 0) { err = -errno; pr_warn("failed to create epoll instance: %s\n", - libbpf_strerror_r(err, msg, sizeof(msg))); + errstr(err)); goto error; } @@ -13292,7 +13496,7 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, err = parse_cpu_mask_file(online_cpus_file, &online, &n); if (err) { - pr_warn("failed to get online CPU mask: %d\n", err); + pr_warn("failed to get online CPU mask: %s\n", errstr(err)); goto error; } @@ -13323,7 +13527,7 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, err = -errno; pr_warn("failed to set cpu #%d, key %d -> perf FD %d: %s\n", cpu, map_key, cpu_buf->fd, - libbpf_strerror_r(err, msg, sizeof(msg))); + errstr(err)); goto error; } @@ -13334,7 +13538,7 @@ static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, err = -errno; pr_warn("failed to epoll_ctl cpu #%d perf FD %d: %s\n", cpu, cpu_buf->fd, - libbpf_strerror_r(err, msg, sizeof(msg))); + errstr(err)); goto error; } j++; @@ -13429,7 +13633,7 @@ int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms) err = perf_buffer__process_records(pb, cpu_buf); if (err) { - pr_warn("error while processing records: %d\n", err); + pr_warn("error while processing records: %s\n", errstr(err)); return libbpf_err(err); } } @@ -13513,7 +13717,8 @@ int perf_buffer__consume(struct perf_buffer *pb) err = perf_buffer__process_records(pb, cpu_buf); if (err) { - pr_warn("perf_buffer: failed to process records in buffer #%d: %d\n", i, err); + pr_warn("perf_buffer: failed to process records in buffer #%d: %s\n", + i, errstr(err)); return libbpf_err(err); } } @@ -13529,7 +13734,7 @@ int bpf_program__set_attach_target(struct bpf_program *prog, if (!prog || attach_prog_fd < 0) return libbpf_err(-EINVAL); - if (prog->obj->loaded) + if (prog->obj->state >= OBJ_LOADED) return libbpf_err(-EINVAL); if (attach_prog_fd && !attach_func_name) { @@ -13542,7 +13747,7 @@ int bpf_program__set_attach_target(struct bpf_program *prog, if (attach_prog_fd) { btf_id = libbpf_find_prog_btf_id(attach_func_name, - attach_prog_fd); + attach_prog_fd, prog->obj->token_fd); if (btf_id < 0) return libbpf_err(btf_id); } else { @@ -13624,14 +13829,14 @@ int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz) fd = open(fcpu, O_RDONLY | O_CLOEXEC); if (fd < 0) { err = -errno; - pr_warn("Failed to open cpu mask file %s: %d\n", fcpu, err); + pr_warn("Failed to open cpu mask file %s: %s\n", fcpu, errstr(err)); return err; } len = read(fd, buf, sizeof(buf)); close(fd); if (len <= 0) { err = len ? -errno : -EINVAL; - pr_warn("Failed to read cpu mask from %s: %d\n", fcpu, err); + pr_warn("Failed to read cpu mask from %s: %s\n", fcpu, errstr(err)); return err; } if (len >= sizeof(buf)) { @@ -13671,14 +13876,15 @@ int libbpf_num_possible_cpus(void) static int populate_skeleton_maps(const struct bpf_object *obj, struct bpf_map_skeleton *maps, - size_t map_cnt) + size_t map_cnt, size_t map_skel_sz) { int i; for (i = 0; i < map_cnt; i++) { - struct bpf_map **map = maps[i].map; - const char *name = maps[i].name; - void **mmaped = maps[i].mmaped; + struct bpf_map_skeleton *map_skel = (void *)maps + i * map_skel_sz; + struct bpf_map **map = map_skel->map; + const char *name = map_skel->name; + void **mmaped = map_skel->mmaped; *map = bpf_object__find_map_by_name(obj, name); if (!*map) { @@ -13695,13 +13901,14 @@ static int populate_skeleton_maps(const struct bpf_object *obj, static int populate_skeleton_progs(const struct bpf_object *obj, struct bpf_prog_skeleton *progs, - size_t prog_cnt) + size_t prog_cnt, size_t prog_skel_sz) { int i; for (i = 0; i < prog_cnt; i++) { - struct bpf_program **prog = progs[i].prog; - const char *name = progs[i].name; + struct bpf_prog_skeleton *prog_skel = (void *)progs + i * prog_skel_sz; + struct bpf_program **prog = prog_skel->prog; + const char *name = prog_skel->name; *prog = bpf_object__find_program_by_name(obj, name); if (!*prog) { @@ -13715,42 +13922,27 @@ static int populate_skeleton_progs(const struct bpf_object *obj, int bpf_object__open_skeleton(struct bpf_object_skeleton *s, const struct bpf_object_open_opts *opts) { - DECLARE_LIBBPF_OPTS(bpf_object_open_opts, skel_opts, - .object_name = s->name, - ); struct bpf_object *obj; int err; - /* Attempt to preserve opts->object_name, unless overriden by user - * explicitly. Overwriting object name for skeletons is discouraged, - * as it breaks global data maps, because they contain object name - * prefix as their own map name prefix. When skeleton is generated, - * bpftool is making an assumption that this name will stay the same. - */ - if (opts) { - memcpy(&skel_opts, opts, sizeof(*opts)); - if (!opts->object_name) - skel_opts.object_name = s->name; - } - - obj = bpf_object__open_mem(s->data, s->data_sz, &skel_opts); - err = libbpf_get_error(obj); - if (err) { - pr_warn("failed to initialize skeleton BPF object '%s': %d\n", - s->name, err); + obj = bpf_object_open(NULL, s->data, s->data_sz, s->name, opts); + if (IS_ERR(obj)) { + err = PTR_ERR(obj); + pr_warn("failed to initialize skeleton BPF object '%s': %s\n", + s->name, errstr(err)); return libbpf_err(err); } *s->obj = obj; - err = populate_skeleton_maps(obj, s->maps, s->map_cnt); + err = populate_skeleton_maps(obj, s->maps, s->map_cnt, s->map_skel_sz); if (err) { - pr_warn("failed to populate skeleton maps for '%s': %d\n", s->name, err); + pr_warn("failed to populate skeleton maps for '%s': %s\n", s->name, errstr(err)); return libbpf_err(err); } - err = populate_skeleton_progs(obj, s->progs, s->prog_cnt); + err = populate_skeleton_progs(obj, s->progs, s->prog_cnt, s->prog_skel_sz); if (err) { - pr_warn("failed to populate skeleton progs for '%s': %d\n", s->name, err); + pr_warn("failed to populate skeleton progs for '%s': %s\n", s->name, errstr(err)); return libbpf_err(err); } @@ -13778,26 +13970,26 @@ int bpf_object__open_subskeleton(struct bpf_object_subskeleton *s) return libbpf_err(-errno); } - err = populate_skeleton_maps(s->obj, s->maps, s->map_cnt); + err = populate_skeleton_maps(s->obj, s->maps, s->map_cnt, s->map_skel_sz); if (err) { - pr_warn("failed to populate subskeleton maps: %d\n", err); + pr_warn("failed to populate subskeleton maps: %s\n", errstr(err)); return libbpf_err(err); } - err = populate_skeleton_progs(s->obj, s->progs, s->prog_cnt); + err = populate_skeleton_progs(s->obj, s->progs, s->prog_cnt, s->prog_skel_sz); if (err) { - pr_warn("failed to populate subskeleton maps: %d\n", err); + pr_warn("failed to populate subskeleton maps: %s\n", errstr(err)); return libbpf_err(err); } for (var_idx = 0; var_idx < s->var_cnt; var_idx++) { - var_skel = &s->vars[var_idx]; + var_skel = (void *)s->vars + var_idx * s->var_skel_sz; map = *var_skel->map; map_type_id = bpf_map__btf_value_type_id(map); map_type = btf__type_by_id(btf, map_type_id); if (!btf_is_datasec(map_type)) { - pr_warn("type for map '%1$s' is not a datasec: %2$s", + pr_warn("type for map '%1$s' is not a datasec: %2$s\n", bpf_map__name(map), __btf_kind_str(btf_kind(map_type))); return libbpf_err(-EINVAL); @@ -13833,52 +14025,18 @@ int bpf_object__load_skeleton(struct bpf_object_skeleton *s) err = bpf_object__load(*s->obj); if (err) { - pr_warn("failed to load BPF skeleton '%s': %d\n", s->name, err); + pr_warn("failed to load BPF skeleton '%s': %s\n", s->name, errstr(err)); return libbpf_err(err); } for (i = 0; i < s->map_cnt; i++) { - struct bpf_map *map = *s->maps[i].map; - size_t mmap_sz = bpf_map_mmap_sz(map); - int prot, map_fd = map->fd; - void **mmaped = s->maps[i].mmaped; + struct bpf_map_skeleton *map_skel = (void *)s->maps + i * s->map_skel_sz; + struct bpf_map *map = *map_skel->map; - if (!mmaped) + if (!map_skel->mmaped) continue; - if (!(map->def.map_flags & BPF_F_MMAPABLE)) { - *mmaped = NULL; - continue; - } - - if (map->def.type == BPF_MAP_TYPE_ARENA) { - *mmaped = map->mmaped; - continue; - } - - if (map->def.map_flags & BPF_F_RDONLY_PROG) - prot = PROT_READ; - else - prot = PROT_READ | PROT_WRITE; - - /* Remap anonymous mmap()-ed "map initialization image" as - * a BPF map-backed mmap()-ed memory, but preserving the same - * memory address. This will cause kernel to change process' - * page table to point to a different piece of kernel memory, - * but from userspace point of view memory address (and its - * contents, being identical at this point) will stay the - * same. This mapping will be released by bpf_object__close() - * as per normal clean up procedure, so we don't need to worry - * about it from skeleton's clean up perspective. - */ - *mmaped = mmap(map->mmaped, mmap_sz, prot, MAP_SHARED | MAP_FIXED, map_fd, 0); - if (*mmaped == MAP_FAILED) { - err = -errno; - *mmaped = NULL; - pr_warn("failed to re-mmap() map '%s': %d\n", - bpf_map__name(map), err); - return libbpf_err(err); - } + *map_skel->mmaped = map->mmaped; } return 0; @@ -13889,8 +14047,9 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) int i, err; for (i = 0; i < s->prog_cnt; i++) { - struct bpf_program *prog = *s->progs[i].prog; - struct bpf_link **link = s->progs[i].link; + struct bpf_prog_skeleton *prog_skel = (void *)s->progs + i * s->prog_skel_sz; + struct bpf_program *prog = *prog_skel->prog; + struct bpf_link **link = prog_skel->link; if (!prog->autoload || !prog->autoattach) continue; @@ -13905,8 +14064,8 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) err = prog->sec_def->prog_attach_fn(prog, prog->sec_def->cookie, link); if (err) { - pr_warn("prog '%s': failed to auto-attach: %d\n", - bpf_program__name(prog), err); + pr_warn("prog '%s': failed to auto-attach: %s\n", + bpf_program__name(prog), errstr(err)); return libbpf_err(err); } @@ -13922,6 +14081,45 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) */ } + + for (i = 0; i < s->map_cnt; i++) { + struct bpf_map_skeleton *map_skel = (void *)s->maps + i * s->map_skel_sz; + struct bpf_map *map = *map_skel->map; + struct bpf_link **link; + + if (!map->autocreate || !map->autoattach) + continue; + + /* only struct_ops maps can be attached */ + if (!bpf_map__is_struct_ops(map)) + continue; + + /* skeleton is created with earlier version of bpftool, notify user */ + if (s->map_skel_sz < offsetofend(struct bpf_map_skeleton, link)) { + pr_warn("map '%s': BPF skeleton version is old, skipping map auto-attachment...\n", + bpf_map__name(map)); + continue; + } + + link = map_skel->link; + if (!link) { + pr_warn("map '%s': BPF map skeleton link is uninitialized\n", + bpf_map__name(map)); + continue; + } + + if (*link) + continue; + + *link = bpf_map__attach_struct_ops(map); + if (!*link) { + err = -errno; + pr_warn("map '%s': failed to auto-attach: %s\n", + bpf_map__name(map), errstr(err)); + return libbpf_err(err); + } + } + return 0; } @@ -13930,11 +14128,25 @@ void bpf_object__detach_skeleton(struct bpf_object_skeleton *s) int i; for (i = 0; i < s->prog_cnt; i++) { - struct bpf_link **link = s->progs[i].link; + struct bpf_prog_skeleton *prog_skel = (void *)s->progs + i * s->prog_skel_sz; + struct bpf_link **link = prog_skel->link; bpf_link__destroy(*link); *link = NULL; } + + if (s->map_skel_sz < sizeof(struct bpf_map_skeleton)) + return; + + for (i = 0; i < s->map_cnt; i++) { + struct bpf_map_skeleton *map_skel = (void *)s->maps + i * s->map_skel_sz; + struct bpf_link **link = map_skel->link; + + if (link) { + bpf_link__destroy(*link); + *link = NULL; + } + } } void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s) @@ -13942,8 +14154,7 @@ void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s) if (!s) return; - if (s->progs) - bpf_object__detach_skeleton(s); + bpf_object__detach_skeleton(s); if (s->obj) bpf_object__close(*s->obj); free(s->maps); |