!131 回合补丁，修复bpf_program__set_attach_target与bpf_object__close不匹配导致的内存泄露问题

From: @jinzig 
Reviewed-by: @chenyuan0, @wonleing 
Signed-off-by: @chenyuan0, @wonleing

backport-libbpf-Free-btf_vmlinux-when-closing-bpf_object.patch

@@ -0,0 +1,36 @@
+From a687461867589b82a1cd4ee261aa374a687584b2 Mon Sep 17 00:00:00 2001
+From: Hao Luo <haoluo@google.com>
+Date: Tue, 22 Aug 2023 12:38:40 -0700
+Subject: [PATCH 1/1] 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
+---
+ src/libbpf.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/src/libbpf.c b/src/libbpf.c
+index b8afe2f..4c3967d 100644
+--- a/src/libbpf.c
++++ b/src/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++)
+-- 
+2.27.0
+

libbpf.spec

@@ -4,7 +4,7 @@
 
 Name:           %{githubname}
 Version:        %{githubver}
-Release:        2
+Release:        3
 Summary:        Libbpf library
 
 License:        LGPLv2 or BSD
@@ -17,6 +17,7 @@ Patch0000:      backport-libbpf-Ensure-FD-3-during-bpf_map__reuse_fd.patch
 Patch0001:      backport-libbpf-Ensure-libbpf-always-opens-files-with-O_CLOEX.patch
 Patch0002:      backport-libbpf-Set-close-on-exec-flag-on-gzopen.patch
 Patch0003:      backport-libbpf-Fix-NULL-pointer-dereference-in_bpf_object__c.patch
+Patch0004:	backport-libbpf-Free-btf_vmlinux-when-closing-bpf_object.patch
 
 # This package supersedes libbpf from kernel-tools,
 # which has default Epoch: 0. By having Epoch: 1
@@ -69,6 +70,10 @@ developing applications that use %{name}
 %{_libdir}/libbpf.a
 
 %changelog
+* Fri May 10 2024 jinzhiguang <jinzhiguang@kylinos.cn> 2:1.2.2-3
+- backport patch from upstream:
+  backport-libbpf-Free-btf_vmlinux-when-closing-bpf_object.patch
+
 * Mon Apr 15 2024 zhangmingyi <zhangmingyi5@huawei.com> 2:1.2.2-2
 - backport patches from upstream:
   backport-libbpf-Fix-NULL-pointer-dereference-in_bpf_object__c.patch