From: Andrey Ignatov <rdna@fb.com>
Date: Wed, 31 Oct 2018 12:57:18 -0700
Subject: libbpf: Fix compile error in libbpf_attach_type_by_name
Patch-mainline: v4.20-rc1
Git-commit: 3615353218744bb60f55170c620ce4dce1a008c7
References: bsc#1109837
Arnaldo Carvalho de Melo reported build error in libbpf when clang
version 3.8.1-24 (tags/RELEASE_381/final) is used:
libbpf.c:2201:36: error: comparison of constant -22 with expression of
type 'const enum bpf_attach_type' is always false
[-Werror,-Wtautological-constant-out-of-range-compare]
if (section_names[i].attach_type == -EINVAL)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~
1 error generated.
Fix the error by keeping "is_attachable" property of a program in a
separate struct field instead of trying to use attach_type itself.
Fixes: 956b620fcf0b ("libbpf: Introduce libbpf_attach_type_by_name")
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
tools/lib/bpf/libbpf.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -2080,19 +2080,19 @@ void bpf_program__set_expected_attach_ty
prog->expected_attach_type = type;
}
-#define BPF_PROG_SEC_IMPL(string, ptype, eatype, atype) \
- { string, sizeof(string) - 1, ptype, eatype, atype }
+#define BPF_PROG_SEC_IMPL(string, ptype, eatype, is_attachable, atype) \
+ { string, sizeof(string) - 1, ptype, eatype, is_attachable, atype }
/* Programs that can NOT be attached. */
-#define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, -EINVAL)
+#define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, 0, 0)
/* Programs that can be attached. */
#define BPF_APROG_SEC(string, ptype, atype) \
- BPF_PROG_SEC_IMPL(string, ptype, 0, atype)
+ BPF_PROG_SEC_IMPL(string, ptype, 0, 1, atype)
/* Programs that must specify expected attach type at load time. */
#define BPF_EAPROG_SEC(string, ptype, eatype) \
- BPF_PROG_SEC_IMPL(string, ptype, eatype, eatype)
+ BPF_PROG_SEC_IMPL(string, ptype, eatype, 1, eatype)
/* Programs that can be attached but attach type can't be identified by section
* name. Kept for backward compatibility.
@@ -2104,6 +2104,7 @@ static const struct {
size_t len;
enum bpf_prog_type prog_type;
enum bpf_attach_type expected_attach_type;
+ int is_attachable;
enum bpf_attach_type attach_type;
} section_names[] = {
BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER),
@@ -2189,7 +2190,7 @@ int libbpf_attach_type_by_name(const cha
for (i = 0; i < ARRAY_SIZE(section_names); i++) {
if (strncmp(name, section_names[i].sec, section_names[i].len))
continue;
- if (section_names[i].attach_type == -EINVAL)
+ if (!section_names[i].is_attachable)
return -EINVAL;
*attach_type = section_names[i].attach_type;
return 0;