[PATCH bpf 1/2] libbpf: Fix btf object leak in load_module_btfs

[Jiri Olsa <jolsa@kernel.org>]

Sashiko found leak in the load_module_btfs error path [1],
which happens when libbpf_ensure_mem fails, then the btf
object is leaked.

Adding missing btf__free object and making sure each iteration
starts with NULL-ed btf pointer.

[1] https://sashiko.dev/#/patchset/20260324081846.2334094-1-jolsa%40kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/lib/bpf/libbpf.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 0be7017800fe..b60ac8094a9e 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -5752,7 +5752,6 @@ static int load_module_btfs(struct bpf_object *obj)
 {
 	struct bpf_btf_info info;
 	struct module_btf *mod_btf;
-	struct btf *btf;
 	char name[64];
 	__u32 id = 0, len;
 	int err, fd;
@@ -5771,6 +5770,8 @@ static int load_module_btfs(struct bpf_object *obj)
 		return 0;
 
 	while (true) {
+		struct btf *btf = NULL;
+
 		err = bpf_btf_get_next_id(id, &id);
 		if (err && errno == ENOENT)
 			return 0;
@@ -5837,6 +5838,7 @@ static int load_module_btfs(struct bpf_object *obj)
 		continue;
 
 err_out:
+		btf__free(btf);
 		close(fd);
 		return err;
 	}
-- 
2.53.0