lib/bpf/linker.c

26 struct src_sec {
62 	struct src_sec *secs;
164 static int linker_sanity_check_elf_symtab(struct src_obj *obj, struct src_sec *sec);
165 static int linker_sanity_check_elf_relos(struct src_obj *obj, struct src_sec *sec);
479 static bool is_ignored_sec(struct src_sec *sec)
516 static struct src_sec *add_src_sec(struct src_obj *obj, const char *sec_name)
518 	struct src_sec *secs = obj->secs, *sec;
554 	struct src_sec *sec;
702 	struct src_sec *sec;
782 static int linker_sanity_check_elf_symtab(struct src_obj *obj, struct src_sec *sec)
784 	struct src_sec *link_sec;
856 static int linker_sanity_check_elf_relos(struct src_obj *obj, struct src_sec *sec)
858 	struct src_sec *link_sec, *sym_sec;
997 static int init_sec(struct bpf_linker *linker, struct dst_sec *dst_sec, struct src_sec *src_sec)
1006 	dst_sec->ephemeral = src_sec->ephemeral;
1009 	if (src_sec->ephemeral)
1027 	name_off = strset__add_str(linker->strtab_strs, src_sec->sec_name);
1032 	shdr->sh_type = src_sec->shdr->sh_type;
1033 	shdr->sh_flags = src_sec->shdr->sh_flags;
1041 	shdr->sh_addralign = src_sec->shdr->sh_addralign;
1042 	shdr->sh_entsize = src_sec->shdr->sh_entsize;
1044 	data->d_type = src_sec->data->d_type;
1047 	data->d_align = src_sec->data->d_align;
1068 static bool secs_match(struct dst_sec *dst, struct src_sec *src)
1089 static bool sec_content_is_same(struct dst_sec *dst_sec, struct src_sec *src_sec)
1091 	if (dst_sec->sec_sz != src_sec->shdr->sh_size)
1093 	if (memcmp(dst_sec->raw_data, src_sec->data->d_buf, dst_sec->sec_sz) != 0)
1098 static int extend_sec(struct bpf_linker *linker, struct dst_sec *dst, struct src_sec *src)
1171 static bool is_data_sec(struct src_sec *sec)
1181 static bool is_relo_sec(struct src_sec *sec)
1193 		struct src_sec *src_sec;
1196 		src_sec = &obj->secs[i];
1197 		if (!is_data_sec(src_sec))
1200 		dst_sec = find_dst_sec_by_name(linker, src_sec->sec_name);
1202 			dst_sec = add_dst_sec(linker, src_sec->sec_name);
1205 			err = init_sec(linker, dst_sec, src_sec);
1207 				pr_warn("failed to init section '%s'\n", src_sec->sec_name);
1211 			if (!secs_match(dst_sec, src_sec)) {
1212 				pr_warn("ELF sections %s are incompatible\n", src_sec->sec_name);
1217 			if (strcmp(src_sec->sec_name, "license") == 0
1218 			    || strcmp(src_sec->sec_name, "version") == 0) {
1219 				if (!sec_content_is_same(dst_sec, src_sec)) {
1220 					pr_warn("non-identical contents of section '%s' are not supported\n", src_sec->sec_name);
1223 				src_sec->skipped = true;
1224 				src_sec->dst_id = dst_sec->id;
1230 		src_sec->dst_id = dst_sec->id;
1232 		err = extend_sec(linker, dst_sec, src_sec);
1242 	struct src_sec *symtab = &obj->secs[obj->symtab_sec_idx];
1746 static struct src_sec *find_src_sec_by_name(struct src_obj *obj, const char *sec_name)
1748 	struct src_sec *sec;
1833 	struct src_sec *src_sec = NULL;
1853 		src_sec = &obj->secs[sym->st_shndx];
1854 		if (src_sec->skipped)
1856 		dst_sec = &linker->secs[src_sec->dst_id];
1884 		 * Those don't have associated src_sec/dst_sec.
1887 			src_sec = find_src_sec_by_name(obj, sec_name);
1888 			if (!src_sec) {
1892 			dst_sec = &linker->secs[src_sec->dst_id];
1964 		dst_sym->st_value = src_sec->dst_off + sym->st_value;
1995 	dst_sym->st_value = (src_sec ? src_sec->dst_off : 0) + sym->st_value;
2030 	struct src_sec *src_symtab = &obj->secs[obj->symtab_sec_idx];
2034 		struct src_sec *src_sec, *src_linked_sec;
2039 		src_sec = &obj->secs[i];
2040 		if (!is_relo_sec(src_sec))
2044 		src_linked_sec = &obj->secs[src_sec->shdr->sh_info];
2048 		dst_sec = find_dst_sec_by_name(linker, src_sec->sec_name);
2050 			dst_sec = add_dst_sec(linker, src_sec->sec_name);
2053 			err = init_sec(linker, dst_sec, src_sec);
2055 				pr_warn("failed to init section '%s'\n", src_sec->sec_name);
2058 		} else if (!secs_match(dst_sec, src_sec)) {
2059 			pr_warn("sections %s are not compatible\n", src_sec->sec_name);
2070 		src_sec->dst_id = dst_sec->id;
2071 		err = extend_sec(linker, dst_sec, src_sec);
2075 		src_rel = src_sec->data->d_buf;
2076 		dst_rel = dst_sec->raw_data + src_sec->dst_off;
2077 		n = src_sec->shdr->sh_size / src_sec->shdr->sh_entsize;
2091 				struct src_sec *sec = &obj->secs[src_sym->st_shndx];
2124 	struct src_sec *symtab = &obj->secs[obj->symtab_sec_idx];
2152 	struct src_sec *sec;
2350 		struct src_sec *src_sec;
2355 		src_sec = &obj->secs[i];
2356 		if (!src_sec->sec_type_id || src_sec->skipped)
2358 		dst_sec = &linker->secs[src_sec->dst_id];
2370 		t = btf__type_by_id(obj->btf, src_sec->sec_type_id);
2424 			dst_var->offset = src_sec->dst_off + src_var->offset;
2455 	struct src_sec *src_sec;
2467 		src_sec = find_src_sec_by_name(obj, sec_name);
2468 		if (!src_sec) {
2472 		dst_sec = &linker->secs[src_sec->dst_id];
2486 			dst_rec->insn_off += src_sec->dst_off;
2496 		src_sec = find_src_sec_by_name(obj, sec_name);
2497 		if (!src_sec) {
2501 		dst_sec = &linker->secs[src_sec->dst_id];
2515 			dst_rec->insn_off += src_sec->dst_off;
2538 		src_sec = find_src_sec_by_name(obj, sec_name);
2539 		if (!src_sec) {
2543 		dst_sec = &linker->secs[src_sec->dst_id];
2557 			dst_rec->insn_off += src_sec->dst_off;