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Diffstat (limited to 'tools/lib/bpf/libbpf.c')
-rw-r--r--tools/lib/bpf/libbpf.c179
1 files changed, 124 insertions, 55 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 35f6dfcdc565..5aa45f89da93 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -171,6 +171,7 @@ int libbpf_strerror(int err, char *buf, size_t size)
struct bpf_program {
/* Index in elf obj file, for relocation use. */
int idx;
+ char *name;
char *section_name;
struct bpf_insn *insns;
size_t insns_cnt;
@@ -283,6 +284,7 @@ static void bpf_program__exit(struct bpf_program *prog)
prog->clear_priv = NULL;
bpf_program__unload(prog);
+ zfree(&prog->name);
zfree(&prog->section_name);
zfree(&prog->insns);
zfree(&prog->reloc_desc);
@@ -293,26 +295,27 @@ static void bpf_program__exit(struct bpf_program *prog)
}
static int
-bpf_program__init(void *data, size_t size, char *name, int idx,
- struct bpf_program *prog)
+bpf_program__init(void *data, size_t size, char *section_name, int idx,
+ struct bpf_program *prog)
{
if (size < sizeof(struct bpf_insn)) {
- pr_warning("corrupted section '%s'\n", name);
+ pr_warning("corrupted section '%s'\n", section_name);
return -EINVAL;
}
bzero(prog, sizeof(*prog));
- prog->section_name = strdup(name);
+ prog->section_name = strdup(section_name);
if (!prog->section_name) {
- pr_warning("failed to alloc name for prog %s\n",
- name);
+ pr_warning("failed to alloc name for prog under section %s\n",
+ section_name);
goto errout;
}
prog->insns = malloc(size);
if (!prog->insns) {
- pr_warning("failed to alloc insns for %s\n", name);
+ pr_warning("failed to alloc insns for prog under section %s\n",
+ section_name);
goto errout;
}
prog->insns_cnt = size / sizeof(struct bpf_insn);
@@ -331,12 +334,12 @@ errout:
static int
bpf_object__add_program(struct bpf_object *obj, void *data, size_t size,
- char *name, int idx)
+ char *section_name, int idx)
{
struct bpf_program prog, *progs;
int nr_progs, err;
- err = bpf_program__init(data, size, name, idx, &prog);
+ err = bpf_program__init(data, size, section_name, idx, &prog);
if (err)
return err;
@@ -350,8 +353,8 @@ bpf_object__add_program(struct bpf_object *obj, void *data, size_t size,
* is still valid, so don't need special treat for
* bpf_close_object().
*/
- pr_warning("failed to alloc a new program '%s'\n",
- name);
+ pr_warning("failed to alloc a new program under section '%s'\n",
+ section_name);
bpf_program__exit(&prog);
return -ENOMEM;
}
@@ -364,6 +367,54 @@ bpf_object__add_program(struct bpf_object *obj, void *data, size_t size,
return 0;
}
+static int
+bpf_object__init_prog_names(struct bpf_object *obj)
+{
+ Elf_Data *symbols = obj->efile.symbols;
+ struct bpf_program *prog;
+ size_t pi, si;
+
+ for (pi = 0; pi < obj->nr_programs; pi++) {
+ char *name = NULL;
+
+ prog = &obj->programs[pi];
+
+ for (si = 0; si < symbols->d_size / sizeof(GElf_Sym) && !name;
+ si++) {
+ GElf_Sym sym;
+
+ if (!gelf_getsym(symbols, si, &sym))
+ continue;
+ if (sym.st_shndx != prog->idx)
+ continue;
+
+ name = elf_strptr(obj->efile.elf,
+ obj->efile.strtabidx,
+ sym.st_name);
+ if (!name) {
+ pr_warning("failed to get sym name string for prog %s\n",
+ prog->section_name);
+ return -LIBBPF_ERRNO__LIBELF;
+ }
+ }
+
+ if (!name) {
+ pr_warning("failed to find sym for prog %s\n",
+ prog->section_name);
+ return -EINVAL;
+ }
+
+ prog->name = strdup(name);
+ if (!prog->name) {
+ pr_warning("failed to allocate memory for prog sym %s\n",
+ name);
+ return -ENOMEM;
+ }
+ }
+
+ return 0;
+}
+
static struct bpf_object *bpf_object__new(const char *path,
void *obj_buf,
size_t obj_buf_sz)
@@ -528,31 +579,6 @@ bpf_object__init_kversion(struct bpf_object *obj,
return 0;
}
-static int
-bpf_object__validate_maps(struct bpf_object *obj)
-{
- int i;
-
- /*
- * If there's only 1 map, the only error case should have been
- * catched in bpf_object__init_maps().
- */
- if (!obj->maps || !obj->nr_maps || (obj->nr_maps == 1))
- return 0;
-
- for (i = 1; i < obj->nr_maps; i++) {
- const struct bpf_map *a = &obj->maps[i - 1];
- const struct bpf_map *b = &obj->maps[i];
-
- if (b->offset - a->offset < sizeof(struct bpf_map_def)) {
- pr_warning("corrupted map section in %s: map \"%s\" too small\n",
- obj->path, a->name);
- return -EINVAL;
- }
- }
- return 0;
-}
-
static int compare_bpf_map(const void *_a, const void *_b)
{
const struct bpf_map *a = _a;
@@ -564,7 +590,7 @@ static int compare_bpf_map(const void *_a, const void *_b)
static int
bpf_object__init_maps(struct bpf_object *obj)
{
- int i, map_idx, nr_maps = 0;
+ int i, map_idx, map_def_sz, nr_maps = 0;
Elf_Scn *scn;
Elf_Data *data;
Elf_Data *symbols = obj->efile.symbols;
@@ -607,6 +633,15 @@ bpf_object__init_maps(struct bpf_object *obj)
if (!nr_maps)
return 0;
+ /* Assume equally sized map definitions */
+ map_def_sz = data->d_size / nr_maps;
+ if (!data->d_size || (data->d_size % nr_maps) != 0) {
+ pr_warning("unable to determine map definition size "
+ "section %s, %d maps in %zd bytes\n",
+ obj->path, nr_maps, data->d_size);
+ return -EINVAL;
+ }
+
obj->maps = calloc(nr_maps, sizeof(obj->maps[0]));
if (!obj->maps) {
pr_warning("alloc maps for object failed\n");
@@ -639,7 +674,7 @@ bpf_object__init_maps(struct bpf_object *obj)
obj->efile.strtabidx,
sym.st_name);
obj->maps[map_idx].offset = sym.st_value;
- if (sym.st_value + sizeof(struct bpf_map_def) > data->d_size) {
+ if (sym.st_value + map_def_sz > data->d_size) {
pr_warning("corrupted maps section in %s: last map \"%s\" too small\n",
obj->path, map_name);
return -EINVAL;
@@ -653,12 +688,40 @@ bpf_object__init_maps(struct bpf_object *obj)
pr_debug("map %d is \"%s\"\n", map_idx,
obj->maps[map_idx].name);
def = (struct bpf_map_def *)(data->d_buf + sym.st_value);
- obj->maps[map_idx].def = *def;
+ /*
+ * If the definition of the map in the object file fits in
+ * bpf_map_def, copy it. Any extra fields in our version
+ * of bpf_map_def will default to zero as a result of the
+ * calloc above.
+ */
+ if (map_def_sz <= sizeof(struct bpf_map_def)) {
+ memcpy(&obj->maps[map_idx].def, def, map_def_sz);
+ } else {
+ /*
+ * Here the map structure being read is bigger than what
+ * we expect, truncate if the excess bits are all zero.
+ * If they are not zero, reject this map as
+ * incompatible.
+ */
+ char *b;
+ for (b = ((char *)def) + sizeof(struct bpf_map_def);
+ b < ((char *)def) + map_def_sz; b++) {
+ if (*b != 0) {
+ pr_warning("maps section in %s: \"%s\" "
+ "has unrecognized, non-zero "
+ "options\n",
+ obj->path, map_name);
+ return -EINVAL;
+ }
+ }
+ memcpy(&obj->maps[map_idx].def, def,
+ sizeof(struct bpf_map_def));
+ }
map_idx++;
}
qsort(obj->maps, obj->nr_maps, sizeof(obj->maps[0]), compare_bpf_map);
- return bpf_object__validate_maps(obj);
+ return 0;
}
static int bpf_object__elf_collect(struct bpf_object *obj)
@@ -766,8 +829,12 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
pr_warning("Corrupted ELF file: index of strtab invalid\n");
return LIBBPF_ERRNO__FORMAT;
}
- if (obj->efile.maps_shndx >= 0)
+ if (obj->efile.maps_shndx >= 0) {
err = bpf_object__init_maps(obj);
+ if (err)
+ goto out;
+ }
+ err = bpf_object__init_prog_names(obj);
out:
return err;
}
@@ -870,11 +937,12 @@ bpf_object__create_maps(struct bpf_object *obj)
struct bpf_map_def *def = &obj->maps[i].def;
int *pfd = &obj->maps[i].fd;
- *pfd = bpf_create_map(def->type,
- def->key_size,
- def->value_size,
- def->max_entries,
- 0);
+ *pfd = bpf_create_map_name(def->type,
+ obj->maps[i].name,
+ def->key_size,
+ def->value_size,
+ def->max_entries,
+ def->map_flags);
if (*pfd < 0) {
size_t j;
int err = *pfd;
@@ -982,7 +1050,7 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
}
static int
-load_program(enum bpf_prog_type type, struct bpf_insn *insns,
+load_program(enum bpf_prog_type type, const char *name, struct bpf_insn *insns,
int insns_cnt, char *license, u32 kern_version, int *pfd)
{
int ret;
@@ -995,8 +1063,8 @@ load_program(enum bpf_prog_type type, struct bpf_insn *insns,
if (!log_buf)
pr_warning("Alloc log buffer for bpf loader error, continue without log\n");
- ret = bpf_load_program(type, insns, insns_cnt, license,
- kern_version, log_buf, BPF_LOG_BUF_SIZE);
+ ret = bpf_load_program_name(type, name, insns, insns_cnt, license,
+ kern_version, log_buf, BPF_LOG_BUF_SIZE);
if (ret >= 0) {
*pfd = ret;
@@ -1021,9 +1089,9 @@ load_program(enum bpf_prog_type type, struct bpf_insn *insns,
if (type != BPF_PROG_TYPE_KPROBE) {
int fd;
- fd = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
- insns_cnt, license, kern_version,
- NULL, 0);
+ fd = bpf_load_program_name(BPF_PROG_TYPE_KPROBE, name,
+ insns, insns_cnt, license,
+ kern_version, NULL, 0);
if (fd >= 0) {
close(fd);
ret = -LIBBPF_ERRNO__PROGTYPE;
@@ -1067,8 +1135,8 @@ bpf_program__load(struct bpf_program *prog,
pr_warning("Program '%s' is inconsistent: nr(%d) != 1\n",
prog->section_name, prog->instances.nr);
}
- err = load_program(prog->type, prog->insns, prog->insns_cnt,
- license, kern_version, &fd);
+ err = load_program(prog->type, prog->name, prog->insns,
+ prog->insns_cnt, license, kern_version, &fd);
if (!err)
prog->instances.fds[0] = fd;
goto out;
@@ -1096,7 +1164,8 @@ bpf_program__load(struct bpf_program *prog,
continue;
}
- err = load_program(prog->type, result.new_insn_ptr,
+ err = load_program(prog->type, prog->name,
+ result.new_insn_ptr,
result.new_insn_cnt,
license, kern_version, &fd);