From: Hao Luo <haoluo@google.com>
Date: Tue, 22 Aug 2023 19:38:40 +0000 (-0700)
Subject: libbpf: Free btf_vmlinux when closing bpf_object
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=29d67fdebc42af6466d1909c60fdd1ef4f3e5240;p=linux.git

libbpf: Free btf_vmlinux when closing bpf_object

I hit a memory leak when testing bpf_program__set_attach_target().
Basically, set_attach_target() may allocate btf_vmlinux, for example,
when setting attach target for bpf_iter programs. But btf_vmlinux
is freed only in bpf_object_load(), which means if we only open
bpf object but not load it, setting attach target may leak
btf_vmlinux.

So let's free btf_vmlinux in bpf_object__close() anyway.

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230822193840.1509809-1-haoluo@google.com
---

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index b8afe2f5bc934..4c3967d94b6d3 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -8423,6 +8423,7 @@ void bpf_object__close(struct bpf_object *obj)
 	bpf_object__elf_finish(obj);
 	bpf_object_unload(obj);
 	btf__free(obj->btf);
+	btf__free(obj->btf_vmlinux);
 	btf_ext__free(obj->btf_ext);
 
 	for (i = 0; i < obj->nr_maps; i++)