libbpf: Free up resources used by inner map definition

It's not enough to just free(map->inner_map), as inner_map itself can
have extra memory allocated, like map name.

Fixes: 646f02ffdd49 ("libbpf: Add BTF-defined map-in-map support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Hengqi Chen <hengqi.chen@gmail.com>
Link: https://lore.kernel.org/bpf/20211107165521.9240-3-andrii@kernel.org

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index dfd15cc..d869ebe 100644 (file)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -9009,7 +9009,10 @@ int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd)
                pr_warn("error: inner_map_fd already specified\n");
                return libbpf_err(-EINVAL);
        }
-       zfree(&map->inner_map);
+       if (map->inner_map) {
+               bpf_map__destroy(map->inner_map);
+               zfree(&map->inner_map);
+       }
        map->inner_map_fd = fd;
        return 0;
 }