selftests/bpf: Fix memory leaks in btf_type_c_dump() helper

Free up memory and resources used by temporary allocated memstream and
btf_dump instance.

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/20211107165521.9240-4-andrii@kernel.org

diff --git a/tools/testing/selftests/bpf/btf_helpers.c b/tools/testing/selftests/bpf/btf_helpers.c
index b5b6b01..3d1a748 100644 (file)
--- a/tools/testing/selftests/bpf/btf_helpers.c
+++ b/tools/testing/selftests/bpf/btf_helpers.c
@@ -251,18 +251,23 @@ const char *btf_type_c_dump(const struct btf *btf)
        d = btf_dump__new(btf, NULL, &opts, btf_dump_printf);
        if (libbpf_get_error(d)) {
                fprintf(stderr, "Failed to create btf_dump instance: %ld\n", libbpf_get_error(d));
-               return NULL;
+               goto err_out;
        }
 
        for (i = 1; i < btf__type_cnt(btf); i++) {
                err = btf_dump__dump_type(d, i);
                if (err) {
                        fprintf(stderr, "Failed to dump type [%d]: %d\n", i, err);
-                       return NULL;
+                       goto err_out;
                }
        }
 
+       btf_dump__free(d);
        fflush(buf_file);
        fclose(buf_file);
        return buf;
+err_out:
+       btf_dump__free(d);
+       fclose(buf_file);
+       return NULL;
 }