libbpf: fix signedness determination in CO-RE relo handling logic

Extracting btf_int_encoding() is only meaningful for BTF_KIND_INT, so we
need to check that first before inferring signedness.

Closes: https://github.com/libbpf/libbpf/issues/704
Reported-by: Lorenz Bauer <lmb@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230824000016.2658017-2-andrii@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
This commit is contained in:
Andrii Nakryiko 2023-08-23 17:00:16 -07:00 committed by Martin KaFai Lau
parent a182e64147
commit f3bdb54f09
1 changed files with 1 additions and 1 deletions

View File

@ -776,7 +776,7 @@ static int bpf_core_calc_field_relo(const char *prog_name,
break;
case BPF_CORE_FIELD_SIGNED:
*val = (btf_is_any_enum(mt) && BTF_INFO_KFLAG(mt->info)) ||
(btf_int_encoding(mt) & BTF_INT_SIGNED);
(btf_is_int(mt) && (btf_int_encoding(mt) & BTF_INT_SIGNED));
if (validate)
*validate = true; /* signedness is never ambiguous */
break;