Commit 8a3aaf9e authored by Geliang Tang's avatar Geliang Tang
Browse files

bpf, btf: Add check_btf_kconfigs helper 

mainline inclusion
from mainline-v6.9-rc1
commit 9e60b0e02550aaf5f2301e49353641a5e3701674
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I9VYQ9
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=9e60b0e02550aaf5f2301e49353641a5e3701674



--------------------------------

This patch extracts duplicate code on error path when btf_get_module_btf()
returns NULL from the functions __register_btf_kfunc_id_set() and
register_btf_id_dtor_kfuncs() into a new helper named check_btf_kconfigs()
to check CONFIG_DEBUG_INFO_BTF and CONFIG_DEBUG_INFO_BTF_MODULES in it.

Signed-off-by: default avatarGeliang Tang <tanggeliang@kylinos.cn>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/fa5537fc55f1e4d0bfd686598c81b7ab9dbd82b7.1707373307.git.tanggeliang@kylinos.cn


Signed-off-by: default avatarMartin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: default avatarJackie Liu <liuyun01@kylinos.cn>
Signed-off-by: default avatarGeliang Tang <tanggeliang@kylinos.cn>
parent 34f05df3

kernel/bpf/btf.c

+15 −18
Original line number Diff line number Diff line
@@ -7531,6 +7531,17 @@ static struct btf *btf_get_module_btf(const struct module *module) 
	return btf;

}



static int check_btf_kconfigs(const struct module *module, const char *feature)

{

	if (!module && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) {

		pr_err("missing vmlinux BTF, cannot register %s\n", feature);

		return -ENOENT;

	}

	if (module && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))

		pr_warn("missing module BTF, cannot register %s\n", feature);

	return 0;

}



BPF_CALL_4(bpf_btf_find_by_name_kind, char *, name, int, name_sz, u32, kind, int, flags)

{

	struct btf *btf = NULL;
@@ -7891,15 +7902,8 @@ static int __register_btf_kfunc_id_set(enum btf_kfunc_hook hook, 
	int ret, i;



	btf = btf_get_module_btf(kset->owner);

	if (!btf) {

		if (!kset->owner && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) {

			pr_err("missing vmlinux BTF, cannot register kfuncs\n");

			return -ENOENT;

		}

		if (kset->owner && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))

			pr_warn("missing module BTF, cannot register kfuncs\n");

		return 0;

	}

	if (!btf)

		return check_btf_kconfigs(kset->owner, "kfunc");

	if (IS_ERR(btf))

		return PTR_ERR(btf);
@@ -7999,15 +8003,8 @@ int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_c 
	int ret;



	btf = btf_get_module_btf(owner);

	if (!btf) {

		if (!owner && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) {

			pr_err("missing vmlinux BTF, cannot register dtor kfuncs\n");

			return -ENOENT;

		}

		if (owner && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))

			pr_warn("missing module BTF, cannot register dtor kfuncs\n");

		return 0;

	}

	if (!btf)

		return check_btf_kconfigs(owner, "dtor kfuncs");

	if (IS_ERR(btf))

		return PTR_ERR(btf);