Re: [PATCH bpf-next] libbpf: reject static entry-point BPF programs
From: Song Liu <song@kernel.org>
Date: 2021-05-14 20:52:16
Also in:
bpf
On Fri, May 14, 2021 at 1:33 PM Andrii Nakryiko [off-list ref] wrote:
Detect use of static entry-point BPF programs (those with SEC() markings) and
emit error message. This is similar to
c1cccec9c636 ("libbpf: Reject static maps") but for BPF programs.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>Acked-by: Song Liu <redacted>
quoted hunk ↗ jump to hunk
--- tools/lib/bpf/libbpf.c | 5 +++++ 1 file changed, 5 insertions(+)diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 182bd3d3f728..e58f51b24574 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c@@ -677,6 +677,11 @@ bpf_object__add_programs(struct bpf_object *obj, Elf_Data *sec_data, return -LIBBPF_ERRNO__FORMAT; } + if (sec_idx != obj->efile.text_shndx && GELF_ST_BIND(sym.st_info) == STB_LOCAL) { + pr_warn("sec '%s': program '%s' is static and not supported\n", sec_name, name); + return -ENOTSUP; + } + pr_debug("sec '%s': found program '%s' at insn offset %zu (%zu bytes), code size %zu insns (%zu bytes)\n", sec_name, name, sec_off / BPF_INSN_SZ, sec_off, prog_sz / BPF_INSN_SZ, prog_sz); --2.30.2