From: Mykyta Yatsenko <yatsenko@xxxxxxxx>
BPF skeletons can be created by previous or newer versions of libbpf,
for which sizeof(bpf_map_skeleton) or bpf_prog_skeleton may differ.
Libbpf should not rely on array indexing, but instead use original
sizes via map_skel_sz/prog_skel_sz for iterating over the
arrays of maps/progs.
Signed-off-by: Mykyta Yatsenko <yatsenko@xxxxxxxx>
---
tools/lib/bpf/libbpf.c | 52 +++++++++++++++++++++++++++---------------
1 file changed, 33 insertions(+), 19 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4a28fac4908a..b46cf29d74b6 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -13712,14 +13712,16 @@ 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_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 = (struct bpf_map_skeleton *)
+ ((char *)maps + map_sz * i);
+ 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) {
@@ -13736,13 +13738,15 @@ 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_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 *cur_prog = (struct bpf_prog_skeleton *)
+ ((char *)progs + prog_sz * i);
+ struct bpf_program **prog = cur_prog->prog;
+ const char *name = cur_prog->name;
*prog = bpf_object__find_program_by_name(obj, name);
if (!*prog) {
@@ -13783,13 +13787,13 @@ int bpf_object__open_skeleton(struct bpf_object_skeleton *s,
}
*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);
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);
return libbpf_err(err);
@@ -13819,13 +13823,13 @@ 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);
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);
return libbpf_err(err);
@@ -13879,10 +13883,12 @@ int bpf_object__load_skeleton(struct bpf_object_skeleton *s)
}
for (i = 0; i < s->map_cnt; i++) {
- struct bpf_map *map = *s->maps[i].map;
+ struct bpf_map_skeleton *map_skel = (struct bpf_map_skeleton *)
+ ((char *)s->maps + s->map_skel_sz * i);
+ struct bpf_map *map = *map_skel->map;
size_t mmap_sz = bpf_map_mmap_sz(map);
int prot, map_fd = map->fd;
- void **mmaped = s->maps[i].mmaped;
+ void **mmaped = map_skel->mmaped;
if (!mmaped)
continue;
@@ -13930,8 +13936,10 @@ 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 = (struct bpf_prog_skeleton *)
+ ((char *)s->progs + s->prog_skel_sz * i);
+ struct bpf_program *prog = *prog_skel->prog;
+ struct bpf_link **link = prog_skel->link;
if (!prog->autoload || !prog->autoattach)
continue;
@@ -13970,8 +13978,10 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s)
return 0;
for (i = 0; i < s->map_cnt; i++) {
- struct bpf_map *map = *s->maps[i].map;
- struct bpf_link **link = s->maps[i].link;
+ struct bpf_map_skeleton *map_skel = (struct bpf_map_skeleton *)
+ ((char *)s->maps + s->map_skel_sz * i);
+ struct bpf_map *map = *map_skel->map;
+ struct bpf_link **link = map_skel->link;
if (!map->autocreate || !map->autoattach)
continue;
@@ -14000,7 +14010,9 @@ 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 = (struct bpf_prog_skeleton *)
+ ((char *)s->progs + s->prog_skel_sz * i);
+ struct bpf_link **link = prog_skel->link;
bpf_link__destroy(*link);
*link = NULL;
@@ -14010,7 +14022,9 @@ void bpf_object__detach_skeleton(struct bpf_object_skeleton *s)
return;
for (i = 0; i < s->map_cnt; i++) {
- struct bpf_link **link = s->maps[i].link;
+ struct bpf_map_skeleton *map_skel = (struct bpf_map_skeleton *)
+ ((char *)s->maps + s->map_skel_sz * i);
+ struct bpf_link **link = map_skel->link;
if (link) {
bpf_link__destroy(*link);
--
2.45.2
