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btf.c
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btf.c
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// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
/* Copyright (c) 2018 Facebook */
#include <endian.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <sys/utsname.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/btf.h>
#include <gelf.h>
#include "btf.h"
#include "bpf.h"
#include "libbpf.h"
#include "libbpf_internal.h"
#include "hashmap.h"
/* make sure libbpf doesn't use kernel-only integer typedefs */
#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
#define BTF_MAX_NR_TYPES 0x7fffffffU
#define BTF_MAX_STR_OFFSET 0x7fffffffU
static struct btf_type btf_void;
struct btf {
union {
struct btf_header *hdr;
void *data;
};
struct btf_type **types;
const char *strings;
void *nohdr_data;
__u32 nr_types;
__u32 types_size;
__u32 data_size;
int fd;
};
static inline __u64 ptr_to_u64(const void *ptr)
{
return (__u64) (unsigned long) ptr;
}
static int btf_add_type(struct btf *btf, struct btf_type *t)
{
if (btf->types_size - btf->nr_types < 2) {
struct btf_type **new_types;
__u32 expand_by, new_size;
if (btf->types_size == BTF_MAX_NR_TYPES)
return -E2BIG;
expand_by = max(btf->types_size >> 2, 16U);
new_size = min(BTF_MAX_NR_TYPES, btf->types_size + expand_by);
new_types = realloc(btf->types, sizeof(*new_types) * new_size);
if (!new_types)
return -ENOMEM;
if (btf->nr_types == 0)
new_types[0] = &btf_void;
btf->types = new_types;
btf->types_size = new_size;
}
btf->types[++(btf->nr_types)] = t;
return 0;
}
static int btf_parse_hdr(struct btf *btf)
{
const struct btf_header *hdr = btf->hdr;
__u32 meta_left;
if (btf->data_size < sizeof(struct btf_header)) {
pr_debug("BTF header not found\n");
return -EINVAL;
}
if (hdr->magic != BTF_MAGIC) {
pr_debug("Invalid BTF magic:%x\n", hdr->magic);
return -EINVAL;
}
if (hdr->version != BTF_VERSION) {
pr_debug("Unsupported BTF version:%u\n", hdr->version);
return -ENOTSUP;
}
if (hdr->flags) {
pr_debug("Unsupported BTF flags:%x\n", hdr->flags);
return -ENOTSUP;
}
meta_left = btf->data_size - sizeof(*hdr);
if (!meta_left) {
pr_debug("BTF has no data\n");
return -EINVAL;
}
if (meta_left < hdr->type_off) {
pr_debug("Invalid BTF type section offset:%u\n", hdr->type_off);
return -EINVAL;
}
if (meta_left < hdr->str_off) {
pr_debug("Invalid BTF string section offset:%u\n", hdr->str_off);
return -EINVAL;
}
if (hdr->type_off >= hdr->str_off) {
pr_debug("BTF type section offset >= string section offset. No type?\n");
return -EINVAL;
}
if (hdr->type_off & 0x02) {
pr_debug("BTF type section is not aligned to 4 bytes\n");
return -EINVAL;
}
btf->nohdr_data = btf->hdr + 1;
return 0;
}
static int btf_parse_str_sec(struct btf *btf)
{
const struct btf_header *hdr = btf->hdr;
const char *start = btf->nohdr_data + hdr->str_off;
const char *end = start + btf->hdr->str_len;
if (!hdr->str_len || hdr->str_len - 1 > BTF_MAX_STR_OFFSET ||
start[0] || end[-1]) {
pr_debug("Invalid BTF string section\n");
return -EINVAL;
}
btf->strings = start;
return 0;
}
static int btf_type_size(struct btf_type *t)
{
int base_size = sizeof(struct btf_type);
__u16 vlen = btf_vlen(t);
switch (btf_kind(t)) {
case BTF_KIND_FWD:
case BTF_KIND_CONST:
case BTF_KIND_VOLATILE:
case BTF_KIND_RESTRICT:
case BTF_KIND_PTR:
case BTF_KIND_TYPEDEF:
case BTF_KIND_FUNC:
return base_size;
case BTF_KIND_INT:
return base_size + sizeof(__u32);
case BTF_KIND_ENUM:
return base_size + vlen * sizeof(struct btf_enum);
case BTF_KIND_ARRAY:
return base_size + sizeof(struct btf_array);
case BTF_KIND_STRUCT:
case BTF_KIND_UNION:
return base_size + vlen * sizeof(struct btf_member);
case BTF_KIND_FUNC_PROTO:
return base_size + vlen * sizeof(struct btf_param);
case BTF_KIND_VAR:
return base_size + sizeof(struct btf_var);
case BTF_KIND_DATASEC:
return base_size + vlen * sizeof(struct btf_var_secinfo);
default:
pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t));
return -EINVAL;
}
}
static int btf_parse_type_sec(struct btf *btf)
{
struct btf_header *hdr = btf->hdr;
void *nohdr_data = btf->nohdr_data;
void *next_type = nohdr_data + hdr->type_off;
void *end_type = nohdr_data + hdr->str_off;
while (next_type < end_type) {
struct btf_type *t = next_type;
int type_size;
int err;
type_size = btf_type_size(t);
if (type_size < 0)
return type_size;
next_type += type_size;
err = btf_add_type(btf, t);
if (err)
return err;
}
return 0;
}
__u32 btf__get_nr_types(const struct btf *btf)
{
return btf->nr_types;
}
const struct btf_type *btf__type_by_id(const struct btf *btf, __u32 type_id)
{
if (type_id > btf->nr_types)
return NULL;
return btf->types[type_id];
}
static bool btf_type_is_void(const struct btf_type *t)
{
return t == &btf_void || btf_is_fwd(t);
}
static bool btf_type_is_void_or_null(const struct btf_type *t)
{
return !t || btf_type_is_void(t);
}
#define MAX_RESOLVE_DEPTH 32
__s64 btf__resolve_size(const struct btf *btf, __u32 type_id)
{
const struct btf_array *array;
const struct btf_type *t;
__u32 nelems = 1;
__s64 size = -1;
int i;
t = btf__type_by_id(btf, type_id);
for (i = 0; i < MAX_RESOLVE_DEPTH && !btf_type_is_void_or_null(t);
i++) {
switch (btf_kind(t)) {
case BTF_KIND_INT:
case BTF_KIND_STRUCT:
case BTF_KIND_UNION:
case BTF_KIND_ENUM:
case BTF_KIND_DATASEC:
size = t->size;
goto done;
case BTF_KIND_PTR:
size = sizeof(void *);
goto done;
case BTF_KIND_TYPEDEF:
case BTF_KIND_VOLATILE:
case BTF_KIND_CONST:
case BTF_KIND_RESTRICT:
case BTF_KIND_VAR:
type_id = t->type;
break;
case BTF_KIND_ARRAY:
array = btf_array(t);
if (nelems && array->nelems > UINT32_MAX / nelems)
return -E2BIG;
nelems *= array->nelems;
type_id = array->type;
break;
default:
return -EINVAL;
}
t = btf__type_by_id(btf, type_id);
}
done:
if (size < 0)
return -EINVAL;
if (nelems && size > UINT32_MAX / nelems)
return -E2BIG;
return nelems * size;
}
int btf__align_of(const struct btf *btf, __u32 id)
{
const struct btf_type *t = btf__type_by_id(btf, id);
__u16 kind = btf_kind(t);
switch (kind) {
case BTF_KIND_INT:
case BTF_KIND_ENUM:
return min(sizeof(void *), (size_t)t->size);
case BTF_KIND_PTR:
return sizeof(void *);
case BTF_KIND_TYPEDEF:
case BTF_KIND_VOLATILE:
case BTF_KIND_CONST:
case BTF_KIND_RESTRICT:
return btf__align_of(btf, t->type);
case BTF_KIND_ARRAY:
return btf__align_of(btf, btf_array(t)->type);
case BTF_KIND_STRUCT:
case BTF_KIND_UNION: {
const struct btf_member *m = btf_members(t);
__u16 vlen = btf_vlen(t);
int i, max_align = 1, align;
for (i = 0; i < vlen; i++, m++) {
align = btf__align_of(btf, m->type);
if (align <= 0)
return align;
max_align = max(max_align, align);
}
return max_align;
}
default:
pr_warn("unsupported BTF_KIND:%u\n", btf_kind(t));
return 0;
}
}
int btf__resolve_type(const struct btf *btf, __u32 type_id)
{
const struct btf_type *t;
int depth = 0;
t = btf__type_by_id(btf, type_id);
while (depth < MAX_RESOLVE_DEPTH &&
!btf_type_is_void_or_null(t) &&
(btf_is_mod(t) || btf_is_typedef(t) || btf_is_var(t))) {
type_id = t->type;
t = btf__type_by_id(btf, type_id);
depth++;
}
if (depth == MAX_RESOLVE_DEPTH || btf_type_is_void_or_null(t))
return -EINVAL;
return type_id;
}
__s32 btf__find_by_name(const struct btf *btf, const char *type_name)
{
__u32 i;
if (!strcmp(type_name, "void"))
return 0;
for (i = 1; i <= btf->nr_types; i++) {
const struct btf_type *t = btf->types[i];
const char *name = btf__name_by_offset(btf, t->name_off);
if (name && !strcmp(type_name, name))
return i;
}
return -ENOENT;
}
__s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name,
__u32 kind)
{
__u32 i;
if (kind == BTF_KIND_UNKN || !strcmp(type_name, "void"))
return 0;
for (i = 1; i <= btf->nr_types; i++) {
const struct btf_type *t = btf->types[i];
const char *name;
if (btf_kind(t) != kind)
continue;
name = btf__name_by_offset(btf, t->name_off);
if (name && !strcmp(type_name, name))
return i;
}
return -ENOENT;
}
void btf__free(struct btf *btf)
{
if (!btf)
return;
if (btf->fd != -1)
close(btf->fd);
free(btf->data);
free(btf->types);
free(btf);
}
struct btf *btf__new(__u8 *data, __u32 size)
{
struct btf *btf;
int err;
btf = calloc(1, sizeof(struct btf));
if (!btf)
return ERR_PTR(-ENOMEM);
btf->fd = -1;
btf->data = malloc(size);
if (!btf->data) {
err = -ENOMEM;
goto done;
}
memcpy(btf->data, data, size);
btf->data_size = size;
err = btf_parse_hdr(btf);
if (err)
goto done;
err = btf_parse_str_sec(btf);
if (err)
goto done;
err = btf_parse_type_sec(btf);
done:
if (err) {
btf__free(btf);
return ERR_PTR(err);
}
return btf;
}
static bool btf_check_endianness(const GElf_Ehdr *ehdr)
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
return ehdr->e_ident[EI_DATA] == ELFDATA2LSB;
#elif __BYTE_ORDER == __BIG_ENDIAN
return ehdr->e_ident[EI_DATA] == ELFDATA2MSB;
#else
# error "Unrecognized __BYTE_ORDER__"
#endif
}
struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext)
{
Elf_Data *btf_data = NULL, *btf_ext_data = NULL;
int err = 0, fd = -1, idx = 0;
struct btf *btf = NULL;
Elf_Scn *scn = NULL;
Elf *elf = NULL;
GElf_Ehdr ehdr;
if (elf_version(EV_CURRENT) == EV_NONE) {
pr_warn("failed to init libelf for %s\n", path);
return ERR_PTR(-LIBBPF_ERRNO__LIBELF);
}
fd = open(path, O_RDONLY);
if (fd < 0) {
err = -errno;
pr_warn("failed to open %s: %s\n", path, strerror(errno));
return ERR_PTR(err);
}
err = -LIBBPF_ERRNO__FORMAT;
elf = elf_begin(fd, ELF_C_READ, NULL);
if (!elf) {
pr_warn("failed to open %s as ELF file\n", path);
goto done;
}
if (!gelf_getehdr(elf, &ehdr)) {
pr_warn("failed to get EHDR from %s\n", path);
goto done;
}
if (!btf_check_endianness(&ehdr)) {
pr_warn("non-native ELF endianness is not supported\n");
goto done;
}
if (!elf_rawdata(elf_getscn(elf, ehdr.e_shstrndx), NULL)) {
pr_warn("failed to get e_shstrndx from %s\n", path);
goto done;
}
while ((scn = elf_nextscn(elf, scn)) != NULL) {
GElf_Shdr sh;
char *name;
idx++;
if (gelf_getshdr(scn, &sh) != &sh) {
pr_warn("failed to get section(%d) header from %s\n",
idx, path);
goto done;
}
name = elf_strptr(elf, ehdr.e_shstrndx, sh.sh_name);
if (!name) {
pr_warn("failed to get section(%d) name from %s\n",
idx, path);
goto done;
}
if (strcmp(name, BTF_ELF_SEC) == 0) {
btf_data = elf_getdata(scn, 0);
if (!btf_data) {
pr_warn("failed to get section(%d, %s) data from %s\n",
idx, name, path);
goto done;
}
continue;
} else if (btf_ext && strcmp(name, BTF_EXT_ELF_SEC) == 0) {
btf_ext_data = elf_getdata(scn, 0);
if (!btf_ext_data) {
pr_warn("failed to get section(%d, %s) data from %s\n",
idx, name, path);
goto done;
}
continue;
}
}
err = 0;
if (!btf_data) {
err = -ENOENT;
goto done;
}
btf = btf__new(btf_data->d_buf, btf_data->d_size);
if (IS_ERR(btf))
goto done;
if (btf_ext && btf_ext_data) {
*btf_ext = btf_ext__new(btf_ext_data->d_buf,
btf_ext_data->d_size);
if (IS_ERR(*btf_ext))
goto done;
} else if (btf_ext) {
*btf_ext = NULL;
}
done:
if (elf)
elf_end(elf);
close(fd);
if (err)
return ERR_PTR(err);
/*
* btf is always parsed before btf_ext, so no need to clean up
* btf_ext, if btf loading failed
*/
if (IS_ERR(btf))
return btf;
if (btf_ext && IS_ERR(*btf_ext)) {
btf__free(btf);
err = PTR_ERR(*btf_ext);
return ERR_PTR(err);
}
return btf;
}
static int compare_vsi_off(const void *_a, const void *_b)
{
const struct btf_var_secinfo *a = _a;
const struct btf_var_secinfo *b = _b;
return a->offset - b->offset;
}
static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
struct btf_type *t)
{
__u32 size = 0, off = 0, i, vars = btf_vlen(t);
const char *name = btf__name_by_offset(btf, t->name_off);
const struct btf_type *t_var;
struct btf_var_secinfo *vsi;
const struct btf_var *var;
int ret;
if (!name) {
pr_debug("No name found in string section for DATASEC kind.\n");
return -ENOENT;
}
/* .extern datasec size and var offsets were set correctly during
* extern collection step, so just skip straight to sorting variables
*/
if (t->size)
goto sort_vars;
ret = bpf_object__section_size(obj, name, &size);
if (ret || !size || (t->size && t->size != size)) {
pr_debug("Invalid size for section %s: %u bytes\n", name, size);
return -ENOENT;
}
t->size = size;
for (i = 0, vsi = btf_var_secinfos(t); i < vars; i++, vsi++) {
t_var = btf__type_by_id(btf, vsi->type);
var = btf_var(t_var);
if (!btf_is_var(t_var)) {
pr_debug("Non-VAR type seen in section %s\n", name);
return -EINVAL;
}
if (var->linkage == BTF_VAR_STATIC)
continue;
name = btf__name_by_offset(btf, t_var->name_off);
if (!name) {
pr_debug("No name found in string section for VAR kind\n");
return -ENOENT;
}
ret = bpf_object__variable_offset(obj, name, &off);
if (ret) {
pr_debug("No offset found in symbol table for VAR %s\n",
name);
return -ENOENT;
}
vsi->offset = off;
}
sort_vars:
qsort(btf_var_secinfos(t), vars, sizeof(*vsi), compare_vsi_off);
return 0;
}
int btf__finalize_data(struct bpf_object *obj, struct btf *btf)
{
int err = 0;
__u32 i;
for (i = 1; i <= btf->nr_types; i++) {
struct btf_type *t = btf->types[i];
/* Loader needs to fix up some of the things compiler
* couldn't get its hands on while emitting BTF. This
* is section size and global variable offset. We use
* the info from the ELF itself for this purpose.
*/
if (btf_is_datasec(t)) {
err = btf_fixup_datasec(obj, btf, t);
if (err)
break;
}
}
return err;
}
int btf__load(struct btf *btf)
{
__u32 log_buf_size = 0;
char *log_buf = NULL;
int err = 0;
if (btf->fd >= 0)
return -EEXIST;
retry_load:
if (log_buf_size) {
log_buf = malloc(log_buf_size);
if (!log_buf)
return -ENOMEM;
*log_buf = 0;
}
btf->fd = bpf_load_btf(btf->data, btf->data_size,
log_buf, log_buf_size, false);
if (btf->fd < 0) {
if (!log_buf || errno == ENOSPC) {
log_buf_size = max((__u32)BPF_LOG_BUF_SIZE,
log_buf_size << 1);
free(log_buf);
goto retry_load;
}
err = -errno;
pr_warn("Error loading BTF: %s(%d)\n", strerror(errno), errno);
if (*log_buf)
pr_warn("%s\n", log_buf);
goto done;
}
done:
free(log_buf);
return err;
}
int btf__fd(const struct btf *btf)
{
return btf->fd;
}
const void *btf__get_raw_data(const struct btf *btf, __u32 *size)
{
*size = btf->data_size;
return btf->data;
}
const char *btf__name_by_offset(const struct btf *btf, __u32 offset)
{
if (offset < btf->hdr->str_len)
return &btf->strings[offset];
else
return NULL;
}
int btf__get_from_id(__u32 id, struct btf **btf)
{
struct bpf_btf_info btf_info = { 0 };
__u32 len = sizeof(btf_info);
__u32 last_size;
int btf_fd;
void *ptr;
int err;
err = 0;
*btf = NULL;
btf_fd = bpf_btf_get_fd_by_id(id);
if (btf_fd < 0)
return 0;
/* we won't know btf_size until we call bpf_obj_get_info_by_fd(). so
* let's start with a sane default - 4KiB here - and resize it only if
* bpf_obj_get_info_by_fd() needs a bigger buffer.
*/
btf_info.btf_size = 4096;
last_size = btf_info.btf_size;
ptr = malloc(last_size);
if (!ptr) {
err = -ENOMEM;
goto exit_free;
}
memset(ptr, 0, last_size);
btf_info.btf = ptr_to_u64(ptr);
err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
if (!err && btf_info.btf_size > last_size) {
void *temp_ptr;
last_size = btf_info.btf_size;
temp_ptr = realloc(ptr, last_size);
if (!temp_ptr) {
err = -ENOMEM;
goto exit_free;
}
ptr = temp_ptr;
memset(ptr, 0, last_size);
btf_info.btf = ptr_to_u64(ptr);
err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
}
if (err || btf_info.btf_size > last_size) {
err = errno;
goto exit_free;
}
*btf = btf__new((__u8 *)(long)btf_info.btf, btf_info.btf_size);
if (IS_ERR(*btf)) {
err = PTR_ERR(*btf);
*btf = NULL;
}
exit_free:
close(btf_fd);
free(ptr);
return err;
}
int btf__get_map_kv_tids(const struct btf *btf, const char *map_name,
__u32 expected_key_size, __u32 expected_value_size,
__u32 *key_type_id, __u32 *value_type_id)
{
const struct btf_type *container_type;
const struct btf_member *key, *value;
const size_t max_name = 256;
char container_name[max_name];
__s64 key_size, value_size;
__s32 container_id;
if (snprintf(container_name, max_name, "____btf_map_%s", map_name) ==
max_name) {
pr_warn("map:%s length of '____btf_map_%s' is too long\n",
map_name, map_name);
return -EINVAL;
}
container_id = btf__find_by_name(btf, container_name);
if (container_id < 0) {
pr_debug("map:%s container_name:%s cannot be found in BTF. Missing BPF_ANNOTATE_KV_PAIR?\n",
map_name, container_name);
return container_id;
}
container_type = btf__type_by_id(btf, container_id);
if (!container_type) {
pr_warn("map:%s cannot find BTF type for container_id:%u\n",
map_name, container_id);
return -EINVAL;
}
if (!btf_is_struct(container_type) || btf_vlen(container_type) < 2) {
pr_warn("map:%s container_name:%s is an invalid container struct\n",
map_name, container_name);
return -EINVAL;
}
key = btf_members(container_type);
value = key + 1;
key_size = btf__resolve_size(btf, key->type);
if (key_size < 0) {
pr_warn("map:%s invalid BTF key_type_size\n", map_name);
return key_size;
}
if (expected_key_size != key_size) {
pr_warn("map:%s btf_key_type_size:%u != map_def_key_size:%u\n",
map_name, (__u32)key_size, expected_key_size);
return -EINVAL;
}
value_size = btf__resolve_size(btf, value->type);
if (value_size < 0) {
pr_warn("map:%s invalid BTF value_type_size\n", map_name);
return value_size;
}
if (expected_value_size != value_size) {
pr_warn("map:%s btf_value_type_size:%u != map_def_value_size:%u\n",
map_name, (__u32)value_size, expected_value_size);
return -EINVAL;
}
*key_type_id = key->type;
*value_type_id = value->type;
return 0;
}
struct btf_ext_sec_setup_param {
__u32 off;
__u32 len;
__u32 min_rec_size;
struct btf_ext_info *ext_info;
const char *desc;
};
static int btf_ext_setup_info(struct btf_ext *btf_ext,
struct btf_ext_sec_setup_param *ext_sec)
{
const struct btf_ext_info_sec *sinfo;
struct btf_ext_info *ext_info;
__u32 info_left, record_size;
/* The start of the info sec (including the __u32 record_size). */
void *info;
if (ext_sec->len == 0)
return 0;
if (ext_sec->off & 0x03) {
pr_debug(".BTF.ext %s section is not aligned to 4 bytes\n",
ext_sec->desc);
return -EINVAL;
}
info = btf_ext->data + btf_ext->hdr->hdr_len + ext_sec->off;
info_left = ext_sec->len;
if (btf_ext->data + btf_ext->data_size < info + ext_sec->len) {
pr_debug("%s section (off:%u len:%u) is beyond the end of the ELF section .BTF.ext\n",
ext_sec->desc, ext_sec->off, ext_sec->len);
return -EINVAL;
}
/* At least a record size */
if (info_left < sizeof(__u32)) {
pr_debug(".BTF.ext %s record size not found\n", ext_sec->desc);
return -EINVAL;
}
/* The record size needs to meet the minimum standard */
record_size = *(__u32 *)info;
if (record_size < ext_sec->min_rec_size ||
record_size & 0x03) {
pr_debug("%s section in .BTF.ext has invalid record size %u\n",
ext_sec->desc, record_size);
return -EINVAL;
}
sinfo = info + sizeof(__u32);
info_left -= sizeof(__u32);
/* If no records, return failure now so .BTF.ext won't be used. */
if (!info_left) {
pr_debug("%s section in .BTF.ext has no records", ext_sec->desc);
return -EINVAL;
}
while (info_left) {
unsigned int sec_hdrlen = sizeof(struct btf_ext_info_sec);
__u64 total_record_size;
__u32 num_records;
if (info_left < sec_hdrlen) {
pr_debug("%s section header is not found in .BTF.ext\n",
ext_sec->desc);
return -EINVAL;
}
num_records = sinfo->num_info;
if (num_records == 0) {
pr_debug("%s section has incorrect num_records in .BTF.ext\n",
ext_sec->desc);
return -EINVAL;
}
total_record_size = sec_hdrlen +
(__u64)num_records * record_size;
if (info_left < total_record_size) {
pr_debug("%s section has incorrect num_records in .BTF.ext\n",
ext_sec->desc);
return -EINVAL;
}
info_left -= total_record_size;
sinfo = (void *)sinfo + total_record_size;
}
ext_info = ext_sec->ext_info;
ext_info->len = ext_sec->len - sizeof(__u32);
ext_info->rec_size = record_size;
ext_info->info = info + sizeof(__u32);
return 0;
}
static int btf_ext_setup_func_info(struct btf_ext *btf_ext)
{
struct btf_ext_sec_setup_param param = {
.off = btf_ext->hdr->func_info_off,
.len = btf_ext->hdr->func_info_len,
.min_rec_size = sizeof(struct bpf_func_info_min),
.ext_info = &btf_ext->func_info,
.desc = "func_info"
};
return btf_ext_setup_info(btf_ext, ¶m);
}
static int btf_ext_setup_line_info(struct btf_ext *btf_ext)
{
struct btf_ext_sec_setup_param param = {
.off = btf_ext->hdr->line_info_off,
.len = btf_ext->hdr->line_info_len,
.min_rec_size = sizeof(struct bpf_line_info_min),
.ext_info = &btf_ext->line_info,
.desc = "line_info",
};
return btf_ext_setup_info(btf_ext, ¶m);
}
static int btf_ext_setup_field_reloc(struct btf_ext *btf_ext)
{
struct btf_ext_sec_setup_param param = {
.off = btf_ext->hdr->field_reloc_off,
.len = btf_ext->hdr->field_reloc_len,
.min_rec_size = sizeof(struct bpf_field_reloc),
.ext_info = &btf_ext->field_reloc_info,
.desc = "field_reloc",
};
return btf_ext_setup_info(btf_ext, ¶m);
}
static int btf_ext_parse_hdr(__u8 *data, __u32 data_size)
{
const struct btf_ext_header *hdr = (struct btf_ext_header *)data;
if (data_size < offsetofend(struct btf_ext_header, hdr_len) ||
data_size < hdr->hdr_len) {
pr_debug("BTF.ext header not found");
return -EINVAL;
}
if (hdr->magic != BTF_MAGIC) {
pr_debug("Invalid BTF.ext magic:%x\n", hdr->magic);
return -EINVAL;