From c3e8c44a90631d2479fec6ecc6ba37e3188f487d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>
Date: Mon, 27 Sep 2021 22:58:10 +0200
Subject: [PATCH] libbpf: Ignore STT_SECTION symbols in 'maps' section
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When parsing legacy map definitions, libbpf would error out when
encountering an STT_SECTION symbol. This becomes a problem because some
versions of binutils will produce SECTION symbols for every section when
processing an ELF file, so BPF files run through 'strip' will end up with
such symbols, making libbpf refuse to load them.
There's not really any reason why erroring out is strictly necessary, so
change libbpf to just ignore SECTION symbols when parsing the ELF.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210927205810.715656-1-toke@redhat.com
---
tools/lib/bpf/libbpf.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index ef5db34bf9139..453148fe8b4b9 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1869,6 +1869,8 @@ static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict)
continue;
if (sym.st_shndx != obj->efile.maps_shndx)
continue;
+ if (GELF_ST_TYPE(sym.st_info) == STT_SECTION)
+ continue;
map = bpf_object__add_map(obj);
if (IS_ERR(map))
@@ -1881,8 +1883,7 @@ static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict)
return -LIBBPF_ERRNO__FORMAT;
}
- if (GELF_ST_TYPE(sym.st_info) == STT_SECTION
- || GELF_ST_BIND(sym.st_info) == STB_LOCAL) {
+ if (GELF_ST_BIND(sym.st_info) == STB_LOCAL) {
pr_warn("map '%s' (legacy): static maps are not supported\n", map_name);
return -ENOTSUP;
}