libbpf: Check if pin_path was set even map fd exist

Say a user reuse map fd after creating a map manually and set the
pin_path, then load the object via libbpf.

In libbpf bpf_object__create_maps(), bpf_object__reuse_map() will
return 0 if there is no pinned map in map->pin_path. Then after
checking if map fd exist, we should also check if pin_path was set
and do bpf_map__pin() instead of continue the loop.

Fix it by creating map if fd not exist and continue checking pin_path
after that.

Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201006021345.3817033-3-liuhangbin@gmail.com
This commit is contained in:
Hangbin Liu 2020-10-06 10:13:44 +08:00 committed by Alexei Starovoitov
parent a0f2b7acb4
commit 2c193d32ca

View File

@ -4256,29 +4256,28 @@ bpf_object__create_maps(struct bpf_object *obj)
if (map->fd >= 0) {
pr_debug("map '%s': skipping creation (preset fd=%d)\n",
map->name, map->fd);
continue;
}
err = bpf_object__create_map(obj, map);
if (err)
goto err_out;
pr_debug("map '%s': created successfully, fd=%d\n", map->name,
map->fd);
if (bpf_map__is_internal(map)) {
err = bpf_object__populate_internal_map(obj, map);
if (err < 0) {
zclose(map->fd);
} else {
err = bpf_object__create_map(obj, map);
if (err)
goto err_out;
pr_debug("map '%s': created successfully, fd=%d\n",
map->name, map->fd);
if (bpf_map__is_internal(map)) {
err = bpf_object__populate_internal_map(obj, map);
if (err < 0) {
zclose(map->fd);
goto err_out;
}
}
}
if (map->init_slots_sz) {
err = init_map_slots(map);
if (err < 0) {
zclose(map->fd);
goto err_out;
if (map->init_slots_sz) {
err = init_map_slots(map);
if (err < 0) {
zclose(map->fd);
goto err_out;
}
}
}