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Diffstat (limited to 'tools/lib/bpf/libbpf.c')
-rw-r--r--tools/lib/bpf/libbpf.c438
1 files changed, 341 insertions, 97 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 7469c7dcc15e..8f480e29a6b0 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -178,6 +178,8 @@ struct bpf_capabilities {
__u32 array_mmap:1;
/* BTF_FUNC_GLOBAL is supported */
__u32 btf_func_global:1;
+ /* kernel support for expected_attach_type in BPF_PROG_LOAD */
+ __u32 exp_attach_type:1;
};
enum reloc_type {
@@ -194,6 +196,22 @@ struct reloc_desc {
int sym_off;
};
+struct bpf_sec_def;
+
+typedef struct bpf_link *(*attach_fn_t)(const struct bpf_sec_def *sec,
+ struct bpf_program *prog);
+
+struct bpf_sec_def {
+ const char *sec;
+ size_t len;
+ enum bpf_prog_type prog_type;
+ enum bpf_attach_type expected_attach_type;
+ bool is_exp_attach_type_optional;
+ bool is_attachable;
+ bool is_attach_btf;
+ attach_fn_t attach_fn;
+};
+
/*
* bpf_prog should be a better name but it has been used in
* linux/filter.h.
@@ -204,6 +222,7 @@ struct bpf_program {
char *name;
int prog_ifindex;
char *section_name;
+ const struct bpf_sec_def *sec_def;
/* section_name with / replaced by _; makes recursive pinning
* in bpf_object__pin_programs easier
*/
@@ -1845,7 +1864,6 @@ resolve_func_ptr(const struct btf *btf, __u32 id, __u32 *res_id)
* type definition, while using only sizeof(void *) space in ELF data section.
*/
static bool get_map_field_int(const char *map_name, const struct btf *btf,
- const struct btf_type *def,
const struct btf_member *m, __u32 *res)
{
const struct btf_type *t = skip_mods_and_typedefs(btf, m->type, NULL);
@@ -1972,19 +1990,19 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
return -EINVAL;
}
if (strcmp(name, "type") == 0) {
- if (!get_map_field_int(map_name, obj->btf, def, m,
+ if (!get_map_field_int(map_name, obj->btf, m,
&map->def.type))
return -EINVAL;
pr_debug("map '%s': found type = %u.\n",
map_name, map->def.type);
} else if (strcmp(name, "max_entries") == 0) {
- if (!get_map_field_int(map_name, obj->btf, def, m,
+ if (!get_map_field_int(map_name, obj->btf, m,
&map->def.max_entries))
return -EINVAL;
pr_debug("map '%s': found max_entries = %u.\n",
map_name, map->def.max_entries);
} else if (strcmp(name, "map_flags") == 0) {
- if (!get_map_field_int(map_name, obj->btf, def, m,
+ if (!get_map_field_int(map_name, obj->btf, m,
&map->def.map_flags))
return -EINVAL;
pr_debug("map '%s': found map_flags = %u.\n",
@@ -1992,8 +2010,7 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
} else if (strcmp(name, "key_size") == 0) {
__u32 sz;
- if (!get_map_field_int(map_name, obj->btf, def, m,
- &sz))
+ if (!get_map_field_int(map_name, obj->btf, m, &sz))
return -EINVAL;
pr_debug("map '%s': found key_size = %u.\n",
map_name, sz);
@@ -2035,8 +2052,7 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
} else if (strcmp(name, "value_size") == 0) {
__u32 sz;
- if (!get_map_field_int(map_name, obj->btf, def, m,
- &sz))
+ if (!get_map_field_int(map_name, obj->btf, m, &sz))
return -EINVAL;
pr_debug("map '%s': found value_size = %u.\n",
map_name, sz);
@@ -2079,8 +2095,7 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
__u32 val;
int err;
- if (!get_map_field_int(map_name, obj->btf, def, m,
- &val))
+ if (!get_map_field_int(map_name, obj->btf, m, &val))
return -EINVAL;
pr_debug("map '%s': found pinning = %u.\n",
map_name, val);
@@ -2284,11 +2299,16 @@ static void bpf_object__sanitize_btf_ext(struct bpf_object *obj)
}
}
-static bool bpf_object__is_btf_mandatory(const struct bpf_object *obj)
+static bool libbpf_needs_btf(const struct bpf_object *obj)
{
return obj->efile.btf_maps_shndx >= 0 ||
- obj->efile.st_ops_shndx >= 0 ||
- obj->nr_extern > 0;
+ obj->efile.st_ops_shndx >= 0 ||
+ obj->nr_extern > 0;
+}
+
+static bool kernel_needs_btf(const struct bpf_object *obj)
+{
+ return obj->efile.st_ops_shndx >= 0;
}
static int bpf_object__init_btf(struct bpf_object *obj,
@@ -2324,7 +2344,7 @@ static int bpf_object__init_btf(struct bpf_object *obj,
}
}
out:
- if (err && bpf_object__is_btf_mandatory(obj)) {
+ if (err && libbpf_needs_btf(obj)) {
pr_warn("BTF is required, but is missing or corrupted.\n");
return err;
}
@@ -2348,7 +2368,7 @@ static int bpf_object__finalize_btf(struct bpf_object *obj)
btf_ext__free(obj->btf_ext);
obj->btf_ext = NULL;
- if (bpf_object__is_btf_mandatory(obj)) {
+ if (libbpf_needs_btf(obj)) {
pr_warn("BTF is required, but is missing or corrupted.\n");
return -ENOENT;
}
@@ -2357,7 +2377,8 @@ static int bpf_object__finalize_btf(struct bpf_object *obj)
static inline bool libbpf_prog_needs_vmlinux_btf(struct bpf_program *prog)
{
- if (prog->type == BPF_PROG_TYPE_STRUCT_OPS)
+ if (prog->type == BPF_PROG_TYPE_STRUCT_OPS ||
+ prog->type == BPF_PROG_TYPE_LSM)
return true;
/* BPF_PROG_TYPE_TRACING programs which do not attach to other programs
@@ -2412,7 +2433,7 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj)
obj->btf_ext = NULL;
}
- if (bpf_object__is_btf_mandatory(obj))
+ if (kernel_needs_btf(obj))
return err;
}
return 0;
@@ -3314,6 +3335,37 @@ static int bpf_object__probe_array_mmap(struct bpf_object *obj)
}
static int
+bpf_object__probe_exp_attach_type(struct bpf_object *obj)
+{
+ struct bpf_load_program_attr attr;
+ struct bpf_insn insns[] = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ };
+ int fd;
+
+ memset(&attr, 0, sizeof(attr));
+ /* use any valid combination of program type and (optional)
+ * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS)
+ * to see if kernel supports expected_attach_type field for
+ * BPF_PROG_LOAD command
+ */
+ attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK;
+ attr.expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE;
+ attr.insns = insns;
+ attr.insns_cnt = ARRAY_SIZE(insns);
+ attr.license = "GPL";
+
+ fd = bpf_load_program_xattr(&attr, NULL, 0);
+ if (fd >= 0) {
+ obj->caps.exp_attach_type = 1;
+ close(fd);
+ return 1;
+ }
+ return 0;
+}
+
+static int
bpf_object__probe_caps(struct bpf_object *obj)
{
int (*probe_fn[])(struct bpf_object *obj) = {
@@ -3323,6 +3375,7 @@ bpf_object__probe_caps(struct bpf_object *obj)
bpf_object__probe_btf_func_global,
bpf_object__probe_btf_datasec,
bpf_object__probe_array_mmap,
+ bpf_object__probe_exp_attach_type,
};
int i, ret;
@@ -3868,6 +3921,10 @@ static struct ids_vec *bpf_core_find_cands(const struct btf *local_btf,
if (str_is_empty(targ_name))
continue;
+ t = skip_mods_and_typedefs(targ_btf, i, NULL);
+ if (!btf_is_composite(t) && !btf_is_array(t))
+ continue;
+
targ_essent_len = bpf_core_essential_name_len(targ_name);
if (targ_essent_len != local_essent_len)
continue;
@@ -4846,8 +4903,8 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
{
struct bpf_load_program_attr load_attr;
char *cp, errmsg[STRERR_BUFSIZE];
- int log_buf_size = BPF_LOG_BUF_SIZE;
- char *log_buf;
+ size_t log_buf_size = 0;
+ char *log_buf = NULL;
int btf_fd, ret;
if (!insns || !insns_cnt)
@@ -4855,13 +4912,19 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
load_attr.prog_type = prog->type;
- load_attr.expected_attach_type = prog->expected_attach_type;
+ /* old kernels might not support specifying expected_attach_type */
+ if (!prog->caps->exp_attach_type && prog->sec_def &&
+ prog->sec_def->is_exp_attach_type_optional)
+ load_attr.expected_attach_type = 0;
+ else
+ load_attr.expected_attach_type = prog->expected_attach_type;
if (prog->caps->name)
load_attr.name = prog->name;
load_attr.insns = insns;
load_attr.insns_cnt = insns_cnt;
load_attr.license = license;
- if (prog->type == BPF_PROG_TYPE_STRUCT_OPS) {
+ if (prog->type == BPF_PROG_TYPE_STRUCT_OPS ||
+ prog->type == BPF_PROG_TYPE_LSM) {
load_attr.attach_btf_id = prog->attach_btf_id;
} else if (prog->type == BPF_PROG_TYPE_TRACING ||
prog->type == BPF_PROG_TYPE_EXT) {
@@ -4887,22 +4950,28 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
load_attr.prog_flags = prog->prog_flags;
retry_load:
- log_buf = malloc(log_buf_size);
- if (!log_buf)
- pr_warn("Alloc log buffer for bpf loader error, continue without log\n");
+ if (log_buf_size) {
+ log_buf = malloc(log_buf_size);
+ if (!log_buf)
+ return -ENOMEM;
+
+ *log_buf = 0;
+ }
ret = bpf_load_program_xattr(&load_attr, log_buf, log_buf_size);
if (ret >= 0) {
- if (load_attr.log_level)
+ if (log_buf && load_attr.log_level)
pr_debug("verifier log:\n%s", log_buf);
*pfd = ret;
ret = 0;
goto out;
}
- if (errno == ENOSPC) {
- log_buf_size <<= 1;
+ if (!log_buf || errno == ENOSPC) {
+ log_buf_size = max((size_t)BPF_LOG_BUF_SIZE,
+ log_buf_size << 1);
+
free(log_buf);
goto retry_load;
}
@@ -4945,8 +5014,9 @@ int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_ver)
{
int err = 0, fd, i, btf_id;
- if (prog->type == BPF_PROG_TYPE_TRACING ||
- prog->type == BPF_PROG_TYPE_EXT) {
+ if ((prog->type == BPF_PROG_TYPE_TRACING ||
+ prog->type == BPF_PROG_TYPE_LSM ||
+ prog->type == BPF_PROG_TYPE_EXT) && !prog->attach_btf_id) {
btf_id = libbpf_find_attach_btf_id(prog);
if (btf_id <= 0)
return btf_id;
@@ -5048,6 +5118,8 @@ bpf_object__load_progs(struct bpf_object *obj, int log_level)
return 0;
}
+static const struct bpf_sec_def *find_sec_def(const char *sec_name);
+
static struct bpf_object *
__bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
const struct bpf_object_open_opts *opts)
@@ -5103,24 +5175,17 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
bpf_object__elf_finish(obj);
bpf_object__for_each_program(prog, obj) {
- enum bpf_prog_type prog_type;
- enum bpf_attach_type attach_type;
-
- if (prog->type != BPF_PROG_TYPE_UNSPEC)
- continue;
-
- err = libbpf_prog_type_by_name(prog->section_name, &prog_type,
- &attach_type);
- if (err == -ESRCH)
+ prog->sec_def = find_sec_def(prog->section_name);
+ if (!prog->sec_def)
/* couldn't guess, but user might manually specify */
continue;
- if (err)
- goto out;
- bpf_program__set_type(prog, prog_type);
- bpf_program__set_expected_attach_type(prog, attach_type);
- if (prog_type == BPF_PROG_TYPE_TRACING ||
- prog_type == BPF_PROG_TYPE_EXT)
+ bpf_program__set_type(prog, prog->sec_def->prog_type);
+ bpf_program__set_expected_attach_type(prog,
+ prog->sec_def->expected_attach_type);
+
+ if (prog->sec_def->prog_type == BPF_PROG_TYPE_TRACING ||
+ prog->sec_def->prog_type == BPF_PROG_TYPE_EXT)
prog->attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0);
}
@@ -6185,6 +6250,7 @@ bool bpf_program__is_##NAME(const struct bpf_program *prog) \
} \
BPF_PROG_TYPE_FNS(socket_filter, BPF_PROG_TYPE_SOCKET_FILTER);
+BPF_PROG_TYPE_FNS(lsm, BPF_PROG_TYPE_LSM);
BPF_PROG_TYPE_FNS(kprobe, BPF_PROG_TYPE_KPROBE);
BPF_PROG_TYPE_FNS(sched_cls, BPF_PROG_TYPE_SCHED_CLS);
BPF_PROG_TYPE_FNS(sched_act, BPF_PROG_TYPE_SCHED_ACT);
@@ -6208,23 +6274,32 @@ void bpf_program__set_expected_attach_type(struct bpf_program *prog,
prog->expected_attach_type = type;
}
-#define BPF_PROG_SEC_IMPL(string, ptype, eatype, is_attachable, btf, atype) \
- { string, sizeof(string) - 1, ptype, eatype, is_attachable, btf, atype }
+#define BPF_PROG_SEC_IMPL(string, ptype, eatype, eatype_optional, \
+ attachable, attach_btf) \
+ { \
+ .sec = string, \
+ .len = sizeof(string) - 1, \
+ .prog_type = ptype, \
+ .expected_attach_type = eatype, \
+ .is_exp_attach_type_optional = eatype_optional, \
+ .is_attachable = attachable, \
+ .is_attach_btf = attach_btf, \
+ }
/* Programs that can NOT be attached. */
#define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, 0, 0, 0)
/* Programs that can be attached. */
#define BPF_APROG_SEC(string, ptype, atype) \
- BPF_PROG_SEC_IMPL(string, ptype, 0, 1, 0, atype)
+ BPF_PROG_SEC_IMPL(string, ptype, atype, true, 1, 0)
/* Programs that must specify expected attach type at load time. */
#define BPF_EAPROG_SEC(string, ptype, eatype) \
- BPF_PROG_SEC_IMPL(string, ptype, eatype, 1, 0, eatype)
+ BPF_PROG_SEC_IMPL(string, ptype, eatype, false, 1, 0)
/* Programs that use BTF to identify attach point */
#define BPF_PROG_BTF(string, ptype, eatype) \
- BPF_PROG_SEC_IMPL(string, ptype, eatype, 0, 1, 0)
+ BPF_PROG_SEC_IMPL(string, ptype, eatype, false, 0, 1)
/* Programs that can be attached but attach type can't be identified by section
* name. Kept for backward compatibility.
@@ -6238,11 +6313,6 @@ void bpf_program__set_expected_attach_type(struct bpf_program *prog,
__VA_ARGS__ \
}
-struct bpf_sec_def;
-
-typedef struct bpf_link *(*attach_fn_t)(const struct bpf_sec_def *sec,
- struct bpf_program *prog);
-
static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec,
struct bpf_program *prog);
static struct bpf_link *attach_tp(const struct bpf_sec_def *sec,
@@ -6251,17 +6321,8 @@ static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec,
struct bpf_program *prog);
static struct bpf_link *attach_trace(const struct bpf_sec_def *sec,
struct bpf_program *prog);
-
-struct bpf_sec_def {
- const char *sec;
- size_t len;
- enum bpf_prog_type prog_type;
- enum bpf_attach_type expected_attach_type;
- bool is_attachable;
- bool is_attach_btf;
- enum bpf_attach_type attach_type;
- attach_fn_t attach_fn;
-};
+static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec,
+ struct bpf_program *prog);
static const struct bpf_sec_def section_defs[] = {
BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER),
@@ -6290,6 +6351,10 @@ static const struct bpf_sec_def section_defs[] = {
.expected_attach_type = BPF_TRACE_FENTRY,
.is_attach_btf = true,
.attach_fn = attach_trace),
+ SEC_DEF("fmod_ret/", TRACING,
+ .expected_attach_type = BPF_MODIFY_RETURN,
+ .is_attach_btf = true,
+ .attach_fn = attach_trace),
SEC_DEF("fexit/", TRACING,
.expected_attach_type = BPF_TRACE_FEXIT,
.is_attach_btf = true,
@@ -6297,6 +6362,10 @@ static const struct bpf_sec_def section_defs[] = {
SEC_DEF("freplace/", EXT,
.is_attach_btf = true,
.attach_fn = attach_trace),
+ SEC_DEF("lsm/", LSM,
+ .is_attach_btf = true,
+ .expected_attach_type = BPF_LSM_MAC,
+ .attach_fn = attach_lsm),
BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP),
BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT),
BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN),
@@ -6559,6 +6628,7 @@ invalid_prog:
}
#define BTF_TRACE_PREFIX "btf_trace_"
+#define BTF_LSM_PREFIX "bpf_lsm_"
#define BTF_MAX_NAME_SIZE 128
static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix,
@@ -6586,9 +6656,15 @@ static inline int __find_vmlinux_btf_id(struct btf *btf, const char *name,
if (attach_type == BPF_TRACE_RAW_TP)
err = find_btf_by_prefix_kind(btf, BTF_TRACE_PREFIX, name,
BTF_KIND_TYPEDEF);
+ else if (attach_type == BPF_LSM_MAC)
+ err = find_btf_by_prefix_kind(btf, BTF_LSM_PREFIX, name,
+ BTF_KIND_FUNC);
else
err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC);
+ if (err <= 0)
+ pr_warn("%s is not found in vmlinux BTF\n", name);
+
return err;
}
@@ -6661,8 +6737,6 @@ static int libbpf_find_attach_btf_id(struct bpf_program *prog)
err = __find_vmlinux_btf_id(prog->obj->btf_vmlinux,
name + section_defs[i].len,
attach_type);
- if (err <= 0)
- pr_warn("%s is not found in vmlinux BTF\n", name);
return err;
}
pr_warn("failed to identify btf_id based on ELF section name '%s'\n", name);
@@ -6683,7 +6757,7 @@ int libbpf_attach_type_by_name(const char *name,
continue;
if (!section_defs[i].is_attachable)
return -EINVAL;
- *attach_type = section_defs[i].attach_type;
+ *attach_type = section_defs[i].expected_attach_type;
return 0;
}
pr_debug("failed to guess attach type based on ELF section name '%s'\n", name);
@@ -6742,6 +6816,17 @@ void *bpf_map__priv(const struct bpf_map *map)
return map ? map->priv : ERR_PTR(-EINVAL);
}
+int bpf_map__set_initial_value(struct bpf_map *map,
+ const void *data, size_t size)
+{
+ if (!map->mmaped || map->libbpf_type == LIBBPF_MAP_KCONFIG ||
+ size != map->def.value_size || map->fd >= 0)
+ return -EINVAL;
+
+ memcpy(map->mmaped, data, size);
+ return 0;
+}
+
bool bpf_map__is_offload_neutral(const struct bpf_map *map)
{
return map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY;
@@ -6932,9 +7017,17 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
struct bpf_link {
int (*detach)(struct bpf_link *link);
int (*destroy)(struct bpf_link *link);
+ char *pin_path; /* NULL, if not pinned */
+ int fd; /* hook FD, -1 if not applicable */
bool disconnected;
};
+/* Replace link's underlying BPF program with the new one */
+int bpf_link__update_program(struct bpf_link *link, struct bpf_program *prog)
+{
+ return bpf_link_update(bpf_link__fd(link), bpf_program__fd(prog), NULL);
+}
+
/* Release "ownership" of underlying BPF resource (typically, BPF program
* attached to some BPF hook, e.g., tracepoint, kprobe, etc). Disconnected
* link, when destructed through bpf_link__destroy() call won't attempt to
@@ -6961,26 +7054,109 @@ int bpf_link__destroy(struct bpf_link *link)
err = link->detach(link);
if (link->destroy)
link->destroy(link);
+ if (link->pin_path)
+ free(link->pin_path);
free(link);
return err;
}
-struct bpf_link_fd {
- struct bpf_link link; /* has to be at the top of struct */
- int fd; /* hook FD */
-};
+int bpf_link__fd(const struct bpf_link *link)
+{
+ return link->fd;
+}
+
+const char *bpf_link__pin_path(const struct bpf_link *link)
+{
+ return link->pin_path;
+}
+
+static int bpf_link__detach_fd(struct bpf_link *link)
+{
+ return close(link->fd);
+}
+
+struct bpf_link *bpf_link__open(const char *path)
+{
+ struct bpf_link *link;
+ int fd;
+
+ fd = bpf_obj_get(path);
+ if (fd < 0) {
+ fd = -errno;
+ pr_warn("failed to open link at %s: %d\n", path, fd);
+ return ERR_PTR(fd);
+ }
+
+ link = calloc(1, sizeof(*link));
+ if (!link) {
+ close(fd);
+ return ERR_PTR(-ENOMEM);
+ }
+ link->detach = &bpf_link__detach_fd;
+ link->fd = fd;
+
+ link->pin_path = strdup(path);
+ if (!link->pin_path) {
+ bpf_link__destroy(link);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return link;
+}
+
+int bpf_link__pin(struct bpf_link *link, const char *path)
+{
+ int err;
+
+ if (link->pin_path)
+ return -EBUSY;
+ err = make_parent_dir(path);
+ if (err)
+ return err;
+ err = check_path(path);
+ if (err)
+ return err;
+
+ link->pin_path = strdup(path);
+ if (!link->pin_path)
+ return -ENOMEM;
+
+ if (bpf_obj_pin(link->fd, link->pin_path)) {
+ err = -errno;
+ zfree(&link->pin_path);
+ return err;
+ }
+
+ pr_debug("link fd=%d: pinned at %s\n", link->fd, link->pin_path);
+ return 0;
+}
+
+int bpf_link__unpin(struct bpf_link *link)
+{
+ int err;
+
+ if (!link->pin_path)
+ return -EINVAL;
+
+ err = unlink(link->pin_path);
+ if (err != 0)
+ return -errno;
+
+ pr_debug("link fd=%d: unpinned from %s\n", link->fd, link->pin_path);
+ zfree(&link->pin_path);
+ return 0;
+}
static int bpf_link__detach_perf_event(struct bpf_link *link)
{
- struct bpf_link_fd *l = (void *)link;
int err;
- err = ioctl(l->fd, PERF_EVENT_IOC_DISABLE, 0);
+ err = ioctl(link->fd, PERF_EVENT_IOC_DISABLE, 0);
if (err)
err = -errno;
- close(l->fd);
+ close(link->fd);
return err;
}
@@ -6988,7 +7164,7 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog,
int pfd)
{
char errmsg[STRERR_BUFSIZE];
- struct bpf_link_fd *link;
+ struct bpf_link *link;
int prog_fd, err;
if (pfd < 0) {
@@ -7006,7 +7182,7 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog,
link = calloc(1, sizeof(*link));
if (!link)
return ERR_PTR(-ENOMEM);
- link->link.detach = &bpf_link__detach_perf_event;
+ link->detach = &bpf_link__detach_perf_event;
link->fd = pfd;
if (ioctl(pfd, PERF_EVENT_IOC_SET_BPF, prog_fd) < 0) {
@@ -7025,7 +7201,7 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog,
libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
return ERR_PTR(err);
}
- return (struct bpf_link *)link;
+ return link;
}
/*
@@ -7313,18 +7489,11 @@ out:
return link;
}
-static int bpf_link__detach_fd(struct bpf_link *link)
-{
- struct bpf_link_fd *l = (void *)link;
-
- return close(l->fd);
-}
-
struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
const char *tp_name)
{
char errmsg[STRERR_BUFSIZE];
- struct bpf_link_fd *link;
+ struct bpf_link *link;
int prog_fd, pfd;
prog_fd = bpf_program__fd(prog);
@@ -7337,7 +7506,7 @@ struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
link = calloc(1, sizeof(*link));
if (!link)
return ERR_PTR(-ENOMEM);
- link->link.detach = &bpf_link__detach_fd;
+ link->detach = &bpf_link__detach_fd;
pfd = bpf_raw_tracepoint_open(tp_name, prog_fd);
if (pfd < 0) {
@@ -7349,7 +7518,7 @@ struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
return ERR_PTR(pfd);
}
link->fd = pfd;
- return (struct bpf_link *)link;
+ return link;
}
static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec,
@@ -7360,10 +7529,11 @@ static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec,
return bpf_program__attach_raw_tracepoint(prog, tp_name);
}
-struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog)
+/* Common logic for all BPF program types that attach to a btf_id */
+static struct bpf_link *bpf_program__attach_btf_id(struct bpf_program *prog)
{
char errmsg[STRERR_BUFSIZE];
- struct bpf_link_fd *link;
+ struct bpf_link *link;
int prog_fd, pfd;
prog_fd = bpf_program__fd(prog);
@@ -7376,13 +7546,13 @@ struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog)
link = calloc(1, sizeof(*link));
if (!link)
return ERR_PTR(-ENOMEM);
- link->link.detach = &bpf_link__detach_fd;
+ link->detach = &bpf_link__detach_fd;
pfd = bpf_raw_tracepoint_open(NULL, prog_fd);
if (pfd < 0) {
pfd = -errno;
free(link);
- pr_warn("program '%s': failed to attach to trace: %s\n",
+ pr_warn("program '%s': failed to attach: %s\n",
bpf_program__title(prog, false),
libbpf_strerror_r(pfd, errmsg, sizeof(errmsg)));
return ERR_PTR(pfd);
@@ -7391,12 +7561,62 @@ struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog)
return (struct bpf_link *)link;
}
+struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog)
+{
+ return bpf_program__attach_btf_id(prog);
+}
+
+struct bpf_link *bpf_program__attach_lsm(struct bpf_program *prog)
+{
+ return bpf_program__attach_btf_id(prog);
+}
+
static struct bpf_link *attach_trace(const struct bpf_sec_def *sec,
struct bpf_program *prog)
{
return bpf_program__attach_trace(prog);
}
+static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec,
+ struct bpf_program *prog)
+{
+ return bpf_program__attach_lsm(prog);
+}
+
+struct bpf_link *
+bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd)
+{
+ enum bpf_attach_type attach_type;
+ char errmsg[STRERR_BUFSIZE];
+ struct bpf_link *link;
+ int prog_fd, link_fd;
+
+ prog_fd = bpf_program__fd(prog);
+ if (prog_fd < 0) {
+ pr_warn("program '%s': can't attach before loaded\n",
+ bpf_program__title(prog, false));
+ return ERR_PTR(-EINVAL);
+ }
+
+ link = calloc(1, sizeof(*link));
+ if (!link)
+ return ERR_PTR(-ENOMEM);
+ link->detach = &bpf_link__detach_fd;
+
+ attach_type = bpf_program__get_expected_attach_type(prog);
+ link_fd = bpf_link_create(prog_fd, cgroup_fd, attach_type, NULL);
+ if (link_fd < 0) {
+ link_fd = -errno;
+ free(link);
+ pr_warn("program '%s': failed to attach to cgroup: %s\n",
+ bpf_program__title(prog, false),
+ libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg)));
+ return ERR_PTR(link_fd);
+ }
+ link->fd = link_fd;
+ return link;
+}
+
struct bpf_link *bpf_program__attach(struct bpf_program *prog)
{
const struct bpf_sec_def *sec_def;
@@ -7410,10 +7630,9 @@ struct bpf_link *bpf_program__attach(struct bpf_program *prog)
static int bpf_link__detach_struct_ops(struct bpf_link *link)
{
- struct bpf_link_fd *l = (void *)link;
__u32 zero = 0;
- if (bpf_map_delete_elem(l->fd, &zero))
+ if (bpf_map_delete_elem(link->fd, &zero))
return -errno;
return 0;
@@ -7422,7 +7641,7 @@ static int bpf_link__detach_struct_ops(struct bpf_link *link)
struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map)
{
struct bpf_struct_ops *st_ops;
- struct bpf_link_fd *link;
+ struct bpf_link *link;
__u32 i, zero = 0;
int err;
@@ -7454,10 +7673,10 @@ struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map)
return ERR_PTR(err);
}
- link->link.detach = bpf_link__detach_struct_ops;
+ link->detach = bpf_link__detach_struct_ops;
link->fd = map->fd;
- return (struct bpf_link *)link;
+ return link;
}
enum bpf_perf_event_ret
@@ -8138,6 +8357,31 @@ void bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear)
}
}
+int bpf_program__set_attach_target(struct bpf_program *prog,
+ int attach_prog_fd,
+ const char *attach_func_name)
+{
+ int btf_id;
+
+ if (!prog || attach_prog_fd < 0 || !attach_func_name)
+ return -EINVAL;
+
+ if (attach_prog_fd)
+ btf_id = libbpf_find_prog_btf_id(attach_func_name,
+ attach_prog_fd);
+ else
+ btf_id = __find_vmlinux_btf_id(prog->obj->btf_vmlinux,
+ attach_func_name,
+ prog->expected_attach_type);
+
+ if (btf_id < 0)
+ return btf_id;
+
+ prog->attach_btf_id = btf_id;
+ prog->attach_prog_fd = attach_prog_fd;
+ return 0;
+}
+
int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz)
{
int err = 0, n, len, start, end = -1;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.