[ Upstream commit90ae54b4c7] ERR_get_error_all()[1] is a openssl v3 API, so to make code compatible with openssl v1 utilize ERR_get_err_line_data instead. Since openssl is already a build requirement for the kernel (minimum requirement openssl 1.0.0), this will allow bpftool to compile where opensslv3 is not available. Signing-related BPF selftests pass with openssl v1. [1] https://docs.openssl.org/3.4/man3/ERR_get_error/ Fixes:40863f4d6e("bpftool: Add support for signing BPF programs") Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Song Liu <song@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20251120084754.640405-2-alan.maguire@oracle.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>