[PATCH bpf-next] bpftool: Fix pretty print dump for maps without BTF loaded
From: Jiri Olsa <jolsa@kernel.org>
Date: 2022-02-16 09:21:09
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [tooling] (bpftool), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Quentin Monnet, Linus Torvalds
The commit e5043894b21f ("bpftool: Use libbpf_get_error() to check error")
fails to dump map without BTF loaded in pretty mode (-p option).
Fixing this by making sure get_map_kv_btf won't fail in case there's
no BTF available for the map.
Cc: Yinjun Zhang <redacted>
Fixes: e5043894b21f ("bpftool: Use libbpf_get_error() to check error")
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/bpf/bpftool/map.c | 29 +++++++++++++----------------
1 file changed, 13 insertions(+), 16 deletions(-)
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 7a341a472ea4..8562add7417d 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c@@ -805,29 +805,28 @@ static int maps_have_btf(int *fds, int nb_fds) static struct btf *btf_vmlinux; -static struct btf *get_map_kv_btf(const struct bpf_map_info *info) +static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf) { - struct btf *btf = NULL; + int err = 0; if (info->btf_vmlinux_value_type_id) { if (!btf_vmlinux) { btf_vmlinux = libbpf_find_kernel_btf(); - if (libbpf_get_error(btf_vmlinux)) + err = libbpf_get_error(btf_vmlinux); + if (err) { p_err("failed to get kernel btf"); + return err; + } } - return btf_vmlinux; + *btf = btf_vmlinux; } else if (info->btf_value_type_id) { - int err; - - btf = btf__load_from_kernel_by_id(info->btf_id); - err = libbpf_get_error(btf); - if (err) { + *btf = btf__load_from_kernel_by_id(info->btf_id); + err = libbpf_get_error(*btf); + if (err) p_err("failed to get btf"); - btf = ERR_PTR(err); - } } - return btf; + return err; } static void free_map_kv_btf(struct btf *btf)
@@ -862,8 +861,7 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr, prev_key = NULL; if (wtr) { - btf = get_map_kv_btf(info); - err = libbpf_get_error(btf); + err = get_map_kv_btf(info, &btf); if (err) { goto exit_free; }
@@ -1054,8 +1052,7 @@ static void print_key_value(struct bpf_map_info *info, void *key, json_writer_t *btf_wtr; struct btf *btf; - btf = get_map_kv_btf(info); - if (libbpf_get_error(btf)) + if (get_map_kv_btf(info, &btf)) return; if (json_output) {
--
2.35.1