From: Andrii Nakryiko andrii@kernel.org
mainline inclusion from mainline-5.16-rc1 commit 8654b4d35e6c915ef456c14320ec8720383e81a7 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
-------------------------------------------------
Remove the assumption about only single instance of each of .rodata and .data internal maps. Nothing changes for '.rodata' and '.data' maps, but new '.rodata.something' map will get 'rodata_something' section in BPF skeleton for them (as well as having struct bpf_map * field in maps section with the same field name).
Signed-off-by: Andrii Nakryiko andrii@kernel.org Signed-off-by: Alexei Starovoitov ast@kernel.org Acked-by: Song Liu songliubraving@fb.com Link: https://lore.kernel.org/bpf/20211021014404.2635234-6-andrii@kernel.org (cherry picked from commit 8654b4d35e6c915ef456c14320ec8720383e81a7) Signed-off-by: Wang Yufen wangyufen@huawei.com --- tools/bpf/bpftool/gen.c | 107 ++++++++++++++++++++++------------------ 1 file changed, 60 insertions(+), 47 deletions(-)
diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index f795907b4061..58b4ddb5545f 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -33,6 +33,11 @@ static void sanitize_identifier(char *name) name[i] = '_'; }
+static bool str_has_prefix(const char *str, const char *prefix) +{ + return strncmp(str, prefix, strlen(prefix)) == 0; +} + static bool str_has_suffix(const char *str, const char *suffix) { size_t i, n1 = strlen(str), n2 = strlen(suffix); @@ -67,23 +72,47 @@ static void get_header_guard(char *guard, const char *obj_name) guard[i] = toupper(guard[i]); }
-static const char *get_map_ident(const struct bpf_map *map) +static bool get_map_ident(const struct bpf_map *map, char *buf, size_t buf_sz) { + static const char *sfxs[] = { ".data", ".rodata", ".bss", ".kconfig" }; const char *name = bpf_map__name(map); + int i, n; + + if (!bpf_map__is_internal(map)) { + snprintf(buf, buf_sz, "%s", name); + return true; + } + + for (i = 0, n = ARRAY_SIZE(sfxs); i < n; i++) { + const char *sfx = sfxs[i], *p; + + p = strstr(name, sfx); + if (p) { + snprintf(buf, buf_sz, "%s", p + 1); + sanitize_identifier(buf); + return true; + } + }
- if (!bpf_map__is_internal(map)) - return name; - - if (str_has_suffix(name, ".data")) - return "data"; - else if (str_has_suffix(name, ".rodata")) - return "rodata"; - else if (str_has_suffix(name, ".bss")) - return "bss"; - else if (str_has_suffix(name, ".kconfig")) - return "kconfig"; - else - return NULL; + return false; +} + +static bool get_datasec_ident(const char *sec_name, char *buf, size_t buf_sz) +{ + static const char *pfxs[] = { ".data", ".rodata", ".bss", ".kconfig" }; + int i, n; + + for (i = 0, n = ARRAY_SIZE(pfxs); i < n; i++) { + const char *pfx = pfxs[i]; + + if (str_has_prefix(sec_name, pfx)) { + snprintf(buf, buf_sz, "%s", sec_name + 1); + sanitize_identifier(buf); + return true; + } + } + + return false; }
static void codegen_btf_dump_printf(void *ctx, const char *fmt, va_list args) @@ -100,24 +129,14 @@ static int codegen_datasec_def(struct bpf_object *obj, const char *sec_name = btf__name_by_offset(btf, sec->name_off); const struct btf_var_secinfo *sec_var = btf_var_secinfos(sec); int i, err, off = 0, pad_cnt = 0, vlen = btf_vlen(sec); - const char *sec_ident; - char var_ident[256]; + char var_ident[256], sec_ident[256]; bool strip_mods = false;
- if (strcmp(sec_name, ".data") == 0) { - sec_ident = "data"; - strip_mods = true; - } else if (strcmp(sec_name, ".bss") == 0) { - sec_ident = "bss"; - strip_mods = true; - } else if (strcmp(sec_name, ".rodata") == 0) { - sec_ident = "rodata"; - strip_mods = true; - } else if (strcmp(sec_name, ".kconfig") == 0) { - sec_ident = "kconfig"; - } else { + if (!get_datasec_ident(sec_name, sec_ident, sizeof(sec_ident))) return 0; - } + + if (strcmp(sec_name, ".kconfig") != 0) + strip_mods = true;
printf(" struct %s__%s {\n", obj_name, sec_ident); for (i = 0; i < vlen; i++, sec_var++) { @@ -385,6 +404,7 @@ static void codegen_destroy(struct bpf_object *obj, const char *obj_name) { struct bpf_program *prog; struct bpf_map *map; + char ident[256];
codegen("\ \n\ @@ -405,10 +425,7 @@ static void codegen_destroy(struct bpf_object *obj, const char *obj_name) }
bpf_object__for_each_map(map, obj) { - const char *ident; - - ident = get_map_ident(map); - if (!ident) + if (!get_map_ident(map, ident, sizeof(ident))) continue; if (bpf_map__is_internal(map) && (bpf_map__def(map)->map_flags & BPF_F_MMAPABLE)) @@ -432,6 +449,7 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h struct bpf_object_load_attr load_attr = {}; DECLARE_LIBBPF_OPTS(gen_loader_opts, opts); struct bpf_map *map; + char ident[256]; int err = 0;
err = bpf_object__gen_loader(obj, &opts); @@ -477,12 +495,10 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h ", obj_name, opts.data_sz); bpf_object__for_each_map(map, obj) { - const char *ident; const void *mmap_data = NULL; size_t mmap_size = 0;
- ident = get_map_ident(map); - if (!ident) + if (!get_map_ident(map, ident, sizeof(ident))) continue;
if (!bpf_map__is_internal(map) || @@ -544,15 +560,15 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h return err; \n\ ", obj_name); bpf_object__for_each_map(map, obj) { - const char *ident, *mmap_flags; + const char *mmap_flags;
- ident = get_map_ident(map); - if (!ident) + if (!get_map_ident(map, ident, sizeof(ident))) continue;
if (!bpf_map__is_internal(map) || !(bpf_map__def(map)->map_flags & BPF_F_MMAPABLE)) continue; + if (bpf_map__def(map)->map_flags & BPF_F_RDONLY_PROG) mmap_flags = "PROT_READ"; else @@ -602,7 +618,8 @@ static int do_skeleton(int argc, char **argv) DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts); char obj_name[MAX_OBJ_NAME_LEN] = "", *obj_data; struct bpf_object *obj = NULL; - const char *file, *ident; + const char *file; + char ident[256]; struct bpf_program *prog; int fd, err = -1; struct bpf_map *map; @@ -673,8 +690,7 @@ static int do_skeleton(int argc, char **argv) }
bpf_object__for_each_map(map, obj) { - ident = get_map_ident(map); - if (!ident) { + if (!get_map_ident(map, ident, sizeof(ident))) { p_err("ignoring unrecognized internal map '%s'...", bpf_map__name(map)); continue; @@ -727,8 +743,7 @@ static int do_skeleton(int argc, char **argv) if (map_cnt) { printf("\tstruct {\n"); bpf_object__for_each_map(map, obj) { - ident = get_map_ident(map); - if (!ident) + if (!get_map_ident(map, ident, sizeof(ident))) continue; if (use_loader) printf("\t\tstruct bpf_map_desc %s;\n", ident); @@ -894,9 +909,7 @@ static int do_skeleton(int argc, char **argv) ); i = 0; bpf_object__for_each_map(map, obj) { - ident = get_map_ident(map); - - if (!ident) + if (!get_map_ident(map, ident, sizeof(ident))) continue;
codegen("\