libbpf: Fix huge memory leak in libbpf_find_vmlinux_btf_id()

BTF object wasn't freed.

Fixes: a6ed02cac690 ("libbpf: Load btf_vmlinux only once per object.")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20200429012111.277390-9-andriin@fb.com

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 445ee90..d86ff82 100644 (file)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -6934,6 +6934,7 @@ int libbpf_find_vmlinux_btf_id(const char *name,
                               enum bpf_attach_type attach_type)
 {
        struct btf *btf;
+       int err;
 
        btf = libbpf_find_kernel_btf();
        if (IS_ERR(btf)) {
@@ -6941,7 +6942,9 @@ int libbpf_find_vmlinux_btf_id(const char *name,
                return -EINVAL;
        }
 
-       return __find_vmlinux_btf_id(btf, name, attach_type);
+       err = __find_vmlinux_btf_id(btf, name, attach_type);
+       btf__free(btf);
+       return err;
 }
 
 static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd)