Commit de91e631 authored by Alan Maguire's avatar Alan Maguire Committed by Andrii Nakryiko
Browse files

libbpf: bpf__find_by_name[_kind] should use btf__get_nr_types() 



When operating on split BTF, btf__find_by_name[_kind] will not
iterate over all types since they use btf->nr_types to show
the number of types to iterate over. For split BTF this is
the number of types _on top of base BTF_, so it will
underestimate the number of types to iterate over, especially
for vmlinux + module BTF, where the latter is much smaller.

Use btf__get_nr_types() instead.

Fixes: ba451366 ("libbpf: Implement basic split BTF support")
Signed-off-by: default avatarAlan Maguire <alan.maguire@oracle.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1605437195-2175-1-git-send-email-alan.maguire@oracle.com
parent b93ef089

tools/lib/bpf/btf.c

+4 −4
Original line number Diff line number Diff line
@@ -674,12 +674,12 @@ int btf__resolve_type(const struct btf *btf, __u32 type_id) 


__s32 btf__find_by_name(const struct btf *btf, const char *type_name)

{

	__u32 i;

	__u32 i, nr_types = btf__get_nr_types(btf);



	if (!strcmp(type_name, "void"))

		return 0;



	for (i = 1; i <= btf->nr_types; i++) {

	for (i = 1; i <= nr_types; i++) {

		const struct btf_type *t = btf__type_by_id(btf, i);

		const char *name = btf__name_by_offset(btf, t->name_off);
@@ -693,12 +693,12 @@ __s32 btf__find_by_name(const struct btf *btf, const char *type_name) 
__s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name,

			     __u32 kind)

{

	__u32 i;

	__u32 i, nr_types = btf__get_nr_types(btf);



	if (kind == BTF_KIND_UNKN || !strcmp(type_name, "void"))

		return 0;



	for (i = 1; i <= btf->nr_types; i++) {

	for (i = 1; i <= nr_types; i++) {

		const struct btf_type *t = btf__type_by_id(btf, i);

		const char *name;