* [PATCH bpf-next 1/2] selftests/bpf: validate skeleton gen handles skipped fields @ 2021-05-13 22:55 Andrii Nakryiko 2021-05-13 22:55 ` [PATCH bpf-next 2/2] libbpf: reject static maps Andrii Nakryiko 0 siblings, 1 reply; 2+ messages in thread From: Andrii Nakryiko @ 2021-05-13 22:55 UTC (permalink / raw) To: bpf, netdev, ast, daniel; +Cc: andrii, kernel-team Adjust static_linked selftests to test a mix of global and static variables and their handling of bpftool's skeleton generation code. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> --- tools/testing/selftests/bpf/prog_tests/static_linked.c | 4 ++-- tools/testing/selftests/bpf/progs/linked_maps1.c | 2 +- tools/testing/selftests/bpf/progs/test_static_linked1.c | 2 +- tools/testing/selftests/bpf/progs/test_static_linked2.c | 2 +- 4 files changed, 5 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/static_linked.c b/tools/testing/selftests/bpf/prog_tests/static_linked.c index ab6acbaf9d8c..5c4e3014e063 100644 --- a/tools/testing/selftests/bpf/prog_tests/static_linked.c +++ b/tools/testing/selftests/bpf/prog_tests/static_linked.c @@ -27,8 +27,8 @@ void test_static_linked(void) /* trigger */ usleep(1); - ASSERT_EQ(skel->bss->var1, 1 * 2 + 2 + 3, "var1"); - ASSERT_EQ(skel->bss->var2, 4 * 3 + 5 + 6, "var2"); + ASSERT_EQ(skel->data->var1, 1 * 2 + 2 + 3, "var1"); + ASSERT_EQ(skel->data->var2, 4 * 3 + 5 + 6, "var2"); cleanup: test_static_linked__destroy(skel); diff --git a/tools/testing/selftests/bpf/progs/linked_maps1.c b/tools/testing/selftests/bpf/progs/linked_maps1.c index 52291515cc72..00bf1ca95986 100644 --- a/tools/testing/selftests/bpf/progs/linked_maps1.c +++ b/tools/testing/selftests/bpf/progs/linked_maps1.c @@ -75,7 +75,7 @@ int BPF_PROG(handler_exit1) val = bpf_map_lookup_elem(&map_weak, &key); if (val) output_weak1 = *val; - + return 0; } diff --git a/tools/testing/selftests/bpf/progs/test_static_linked1.c b/tools/testing/selftests/bpf/progs/test_static_linked1.c index cae304045d9c..4f0b612e1661 100644 --- a/tools/testing/selftests/bpf/progs/test_static_linked1.c +++ b/tools/testing/selftests/bpf/progs/test_static_linked1.c @@ -7,7 +7,7 @@ /* 8-byte aligned .data */ static volatile long static_var1 = 2; static volatile int static_var2 = 3; -int var1 = 0; +int var1 = -1; /* 4-byte aligned .rodata */ const volatile int rovar1; diff --git a/tools/testing/selftests/bpf/progs/test_static_linked2.c b/tools/testing/selftests/bpf/progs/test_static_linked2.c index c54c4e865ed8..766ebd502a60 100644 --- a/tools/testing/selftests/bpf/progs/test_static_linked2.c +++ b/tools/testing/selftests/bpf/progs/test_static_linked2.c @@ -7,7 +7,7 @@ /* 4-byte aligned .data */ static volatile int static_var1 = 5; static volatile int static_var2 = 6; -int var2 = 0; +int var2 = -1; /* 8-byte aligned .rodata */ const volatile long rovar2; -- 2.30.2 ^ permalink raw reply related [flat|nested] 2+ messages in thread
* [PATCH bpf-next 2/2] libbpf: reject static maps 2021-05-13 22:55 [PATCH bpf-next 1/2] selftests/bpf: validate skeleton gen handles skipped fields Andrii Nakryiko @ 2021-05-13 22:55 ` Andrii Nakryiko 0 siblings, 0 replies; 2+ messages in thread From: Andrii Nakryiko @ 2021-05-13 22:55 UTC (permalink / raw) To: bpf, netdev, ast, daniel; +Cc: andrii, kernel-team Static maps never really worked with libbpf, because all such maps were always silently resolved to the very first map. Detect static maps (both legacy and BTF-defined) and report user-friendly error. Tested locally by switching few maps (legacy and BTF-defined) in selftests to static ones and verifying that now libbpf rejects them loudly. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> --- tools/lib/bpf/libbpf.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b8cf93fa1b4d..ac5ab903d42b 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1795,7 +1795,6 @@ static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) if (!symbols) return -EINVAL; - scn = elf_sec_by_idx(obj, obj->efile.maps_shndx); data = elf_sec_data(obj, scn); if (!scn || !data) { @@ -1848,6 +1847,7 @@ static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) if (IS_ERR(map)) return PTR_ERR(map); + map_name = elf_sym_str(obj, sym.st_name); if (!map_name) { pr_warn("failed to get map #%d name sym string for obj %s\n", @@ -1855,6 +1855,12 @@ 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) { + pr_warn("map '%s' (legacy): static maps are not supported\n", map_name); + return -ENOTSUP; + } + map->libbpf_type = LIBBPF_MAP_UNSPEC; map->sec_idx = sym.st_shndx; map->sec_offset = sym.st_value; @@ -2262,6 +2268,16 @@ static void fill_map_from_def(struct bpf_map *map, const struct btf_map_def *def pr_debug("map '%s': found inner map definition.\n", map->name); } +static const char *btf_var_linkage_str(__u32 linkage) +{ + switch (linkage) { + case BTF_VAR_STATIC: return "static"; + case BTF_VAR_GLOBAL_ALLOCATED: return "global"; + case BTF_VAR_GLOBAL_EXTERN: return "extern"; + default: return "unknown"; + } +} + static int bpf_object__init_user_btf_map(struct bpf_object *obj, const struct btf_type *sec, int var_idx, int sec_idx, @@ -2294,10 +2310,9 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, map_name, btf_kind_str(var)); return -EINVAL; } - if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED && - var_extra->linkage != BTF_VAR_STATIC) { - pr_warn("map '%s': unsupported var linkage %u.\n", - map_name, var_extra->linkage); + if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED) { + pr_warn("map '%s': unsupported map linkage %s.\n", + map_name, btf_var_linkage_str(var_extra->linkage)); return -EOPNOTSUPP; } -- 2.30.2 ^ permalink raw reply related [flat|nested] 2+ messages in thread
end of thread, other threads:[~2021-05-13 23:05 UTC | newest] Thread overview: 2+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2021-05-13 22:55 [PATCH bpf-next 1/2] selftests/bpf: validate skeleton gen handles skipped fields Andrii Nakryiko 2021-05-13 22:55 ` [PATCH bpf-next 2/2] libbpf: reject static maps Andrii Nakryiko
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