From e5043894b21f7d99d3db31ad06308d6c5726caa6 Mon Sep 17 00:00:00 2001 From: Hengqi Chen Date: Mon, 15 Nov 2021 09:24:36 +0800 Subject: [PATCH] bpftool: Use libbpf_get_error() to check error Currently, LIBBPF_STRICT_ALL mode is enabled by default for bpftool which means on error cases, some libbpf APIs would return NULL pointers. This makes IS_ERR check failed to detect such cases and result in segfault error. Use libbpf_get_error() instead like we do in libbpf itself. Signed-off-by: Hengqi Chen Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211115012436.3143318-1-hengqi.chen@gmail.com --- tools/bpf/bpftool/btf.c | 9 +++++---- tools/bpf/bpftool/gen.c | 10 ++++++---- tools/bpf/bpftool/iter.c | 7 ++++--- tools/bpf/bpftool/map.c | 10 +++++----- tools/bpf/bpftool/struct_ops.c | 14 +++++++------- 5 files changed, 27 insertions(+), 23 deletions(-) diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index c7e3b0b0029e..59833125ac0a 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -421,8 +421,9 @@ static int dump_btf_c(const struct btf *btf, int err = 0, i; d = btf_dump__new(btf, btf_dump_printf, NULL, NULL); - if (IS_ERR(d)) - return PTR_ERR(d); + err = libbpf_get_error(d); + if (err) + return err; printf("#ifndef __VMLINUX_H__\n"); printf("#define __VMLINUX_H__\n"); @@ -549,8 +550,8 @@ static int do_dump(int argc, char **argv) } btf = btf__parse_split(*argv, base ?: base_btf); - if (IS_ERR(btf)) { - err = -PTR_ERR(btf); + err = libbpf_get_error(btf); + if (err) { btf = NULL; p_err("failed to load BTF from %s: %s", *argv, strerror(err)); diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 89f0e828bbfa..997a2865e04a 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -219,8 +219,9 @@ static int codegen_datasecs(struct bpf_object *obj, const char *obj_name) int i, err = 0; d = btf_dump__new(btf, codegen_btf_dump_printf, NULL, NULL); - if (IS_ERR(d)) - return PTR_ERR(d); + err = libbpf_get_error(d); + if (err) + return err; bpf_object__for_each_map(map, obj) { /* only generate definitions for memory-mapped internal maps */ @@ -719,10 +720,11 @@ static int do_skeleton(int argc, char **argv) get_obj_name(obj_name, file); opts.object_name = obj_name; obj = bpf_object__open_mem(obj_data, file_sz, &opts); - if (IS_ERR(obj)) { + err = libbpf_get_error(obj); + if (err) { char err_buf[256]; - libbpf_strerror(PTR_ERR(obj), err_buf, sizeof(err_buf)); + libbpf_strerror(err, err_buf, sizeof(err_buf)); p_err("failed to open BPF object file: %s", err_buf); obj = NULL; goto out; diff --git a/tools/bpf/bpftool/iter.c b/tools/bpf/bpftool/iter.c index 6c0de647b8ad..f88fdc820d23 100644 --- a/tools/bpf/bpftool/iter.c +++ b/tools/bpf/bpftool/iter.c @@ -46,7 +46,8 @@ static int do_pin(int argc, char **argv) } obj = bpf_object__open(objfile); - if (IS_ERR(obj)) { + err = libbpf_get_error(obj); + if (err) { p_err("can't open objfile %s", objfile); goto close_map_fd; } @@ -64,8 +65,8 @@ static int do_pin(int argc, char **argv) } link = bpf_program__attach_iter(prog, &iter_opts); - if (IS_ERR(link)) { - err = PTR_ERR(link); + err = libbpf_get_error(link); + if (err) { p_err("attach_iter failed for program %s", bpf_program__name(prog)); goto close_obj; diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index 68cb121e65c4..25b258804f11 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -812,7 +812,7 @@ static struct btf *get_map_kv_btf(const struct bpf_map_info *info) if (info->btf_vmlinux_value_type_id) { if (!btf_vmlinux) { btf_vmlinux = libbpf_find_kernel_btf(); - if (IS_ERR(btf_vmlinux)) + if (libbpf_get_error(btf_vmlinux)) p_err("failed to get kernel btf"); } return btf_vmlinux; @@ -832,13 +832,13 @@ static struct btf *get_map_kv_btf(const struct bpf_map_info *info) static void free_map_kv_btf(struct btf *btf) { - if (!IS_ERR(btf) && btf != btf_vmlinux) + if (!libbpf_get_error(btf) && btf != btf_vmlinux) btf__free(btf); } static void free_btf_vmlinux(void) { - if (!IS_ERR(btf_vmlinux)) + if (!libbpf_get_error(btf_vmlinux)) btf__free(btf_vmlinux); } @@ -863,8 +863,8 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr, if (wtr) { btf = get_map_kv_btf(info); - if (IS_ERR(btf)) { - err = PTR_ERR(btf); + err = libbpf_get_error(btf); + if (err) { goto exit_free; } diff --git a/tools/bpf/bpftool/struct_ops.c b/tools/bpf/bpftool/struct_ops.c index 20f803dce2e4..cbdca37a53f0 100644 --- a/tools/bpf/bpftool/struct_ops.c +++ b/tools/bpf/bpftool/struct_ops.c @@ -32,7 +32,7 @@ static const struct btf *get_btf_vmlinux(void) return btf_vmlinux; btf_vmlinux = libbpf_find_kernel_btf(); - if (IS_ERR(btf_vmlinux)) + if (libbpf_get_error(btf_vmlinux)) p_err("struct_ops requires kernel CONFIG_DEBUG_INFO_BTF=y"); return btf_vmlinux; @@ -45,7 +45,7 @@ static const char *get_kern_struct_ops_name(const struct bpf_map_info *info) const char *st_ops_name; kern_btf = get_btf_vmlinux(); - if (IS_ERR(kern_btf)) + if (libbpf_get_error(kern_btf)) return ""; t = btf__type_by_id(kern_btf, info->btf_vmlinux_value_type_id); @@ -63,7 +63,7 @@ static __s32 get_map_info_type_id(void) return map_info_type_id; kern_btf = get_btf_vmlinux(); - if (IS_ERR(kern_btf)) { + if (libbpf_get_error(kern_btf)) { map_info_type_id = PTR_ERR(kern_btf); return map_info_type_id; } @@ -415,7 +415,7 @@ static int do_dump(int argc, char **argv) } kern_btf = get_btf_vmlinux(); - if (IS_ERR(kern_btf)) + if (libbpf_get_error(kern_btf)) return -1; if (!json_output) { @@ -495,7 +495,7 @@ static int do_register(int argc, char **argv) file = GET_ARG(); obj = bpf_object__open(file); - if (IS_ERR_OR_NULL(obj)) + if (libbpf_get_error(obj)) return -1; set_max_rlimit(); @@ -516,7 +516,7 @@ static int do_register(int argc, char **argv) continue; link = bpf_map__attach_struct_ops(map); - if (IS_ERR(link)) { + if (libbpf_get_error(link)) { p_err("can't register struct_ops %s: %s", bpf_map__name(map), strerror(-PTR_ERR(link))); @@ -596,7 +596,7 @@ int do_struct_ops(int argc, char **argv) err = cmd_select(cmds, argc, argv, do_help); - if (!IS_ERR(btf_vmlinux)) + if (!libbpf_get_error(btf_vmlinux)) btf__free(btf_vmlinux); return err; -- 2.25.1