@@ -162,6 +162,17 @@ static inline void amd64_rewrite_rip_symbol(amd64_asm_operand_t *operand) {
162162 operand -> value = r ;
163163}
164164
165+ static inline void amd64_rewrite_fs_offset_symbol (amd64_asm_operand_t * operand ) {
166+ operand -> type = AMD64_ASM_OPERAND_TYPE_SEG_OFFSET ;
167+ operand -> size = operand -> size ;
168+
169+ asm_seg_offset_t * s = NEW (asm_seg_offset_t );
170+ s -> name = "fs" ;
171+ s -> offset = 0 ;
172+ operand -> value = s ;
173+ }
174+
175+
165176static inline amd64_asm_operand_t * extract_symbol_operand (amd64_asm_inst_t * operation ) {
166177 for (int i = 0 ; i < operation -> count ; ++ i ) {
167178 amd64_asm_operand_t * operand = operation -> operands [i ];
@@ -192,11 +203,13 @@ static inline int amd64_gotplt_entry_type(uint64_t relocate_type) {
192203 case R_X86_64_JUMP_SLOT :
193204 case R_X86_64_COPY :
194205 case R_X86_64_RELATIVE :
206+ case R_X86_64_TPOFF32 :
207+ case R_X86_64_TPOFF64 :
195208 return NO_GOTPLT_ENTRY ;
196209
197- /* The following relocs wouldn't normally need GOT or PLT
198- slots, but we need them for simplicity in the link
199- editor part. See our caller for comments. */
210+ /* The following relocs wouldn't normally need GOT or PLT
211+ slots, but we need them for simplicity in the link
212+ editor part. See our caller for comments. */
200213 case R_X86_64_32 :
201214 case R_X86_64_32S :
202215 case R_X86_64_64 :
@@ -217,9 +230,9 @@ static inline int amd64_gotplt_entry_type(uint64_t relocate_type) {
217230 case R_X86_64_TLSGD :
218231 case R_X86_64_TLSLD :
219232 case R_X86_64_DTPOFF32 :
220- case R_X86_64_TPOFF32 :
233+ // case R_X86_64_TPOFF32:
221234 case R_X86_64_DTPOFF64 :
222- case R_X86_64_TPOFF64 :
235+ // case R_X86_64_TPOFF64:
223236 case R_X86_64_REX_GOTPCRELX :
224237 case R_X86_64_PLT32 :
225238 case R_X86_64_PLTOFF64 :
@@ -277,11 +290,12 @@ static inline int8_t amd64_is_code_relocate(uint64_t relocate_type) {
277290 case R_X86_64_TLSGD :
278291 case R_X86_64_TLSLD :
279292 case R_X86_64_DTPOFF32 :
280- case R_X86_64_TPOFF32 :
293+ // case R_X86_64_TPOFF32:
281294 case R_X86_64_DTPOFF64 :
282295 case R_X86_64_TPOFF64 :
283296 return 0 ;
284297
298+ // case R_X86_64_TPOFF32:
285299 case R_X86_64_PC32 :
286300 case R_X86_64_PC64 :
287301 case R_X86_64_PLT32 :
@@ -311,7 +325,8 @@ elf_amd64_relocate(elf_context_t *ctx, Elf64_Rela *rel, int type, uint8_t *ptr,
311325 case R_X86_64_PLT32 :
312326 /* fallthrough: val already holds the PLT slot address */
313327
314- plt32pc32 : {
328+ plt32pc32 :
329+ {
315330 // 相对地址计算，
316331 // addr 保存了符号的使用位置（加载到虚拟内存中的位置）
317332 // val 保存了符号的定义的位置（加载到虚拟内存中的位置）
@@ -323,7 +338,8 @@ elf_amd64_relocate(elf_context_t *ctx, Elf64_Rela *rel, int type, uint8_t *ptr,
323338 }
324339 // 小端写入
325340 add32le (ptr , diff );
326- } break ;
341+ }
342+ break ;
327343
328344 case R_X86_64_COPY :
329345 break ;
@@ -345,7 +361,7 @@ elf_amd64_relocate(elf_context_t *ctx, Elf64_Rela *rel, int type, uint8_t *ptr,
345361 case R_X86_64_GOTPCRELX :
346362 case R_X86_64_REX_GOTPCRELX :
347363 add32le (ptr , ctx -> got -> sh_addr - addr +
348- elf_get_sym_attr (ctx , sym_index , 0 )-> got_offset - 4 );
364+ elf_get_sym_attr (ctx , sym_index , 0 )-> got_offset - 4 );
349365 break ;
350366 case R_X86_64_GOTPC32 :
351367 add32le (ptr , ctx -> got -> sh_addr - addr + rel -> r_addend );
@@ -420,9 +436,11 @@ elf_amd64_relocate(elf_context_t *ctx, Elf64_Rela *rel, int type, uint8_t *ptr,
420436 case R_X86_64_TPOFF32 : {
421437 Elf64_Sym * sym = & ((Elf64_Sym * ) ctx -> symtab_section -> data )[sym_index ];
422438 section_t * s = SEC_TACK (sym -> st_shndx );
423- int32_t x ;
424439
425- x = val - s -> sh_addr - s -> data_count ;
440+ int32_t x = - val ;
441+ log_debug ("[elf_amd64_relocate] R_X86_64_TPOFF32, val=%ld, s->sh_addr=%ld, s->data_count=%ld, x=%lx" , val ,
442+ s -> sh_addr , s -> data_count , (uint32_t )x );
443+
426444 add32le (ptr , x );
427445 break ;
428446 }
@@ -517,6 +535,11 @@ static inline void elf_amd64_operation_encodings(elf_context_t *ctx, slice_t *cl
517535 temp -> rel_symbol = symbol_operand -> name ;
518536 }
519537 } else {
538+ int st_type = STT_OBJECT ;
539+ if (symbol_operand -> is_tls ) {
540+ st_type = STT_TLS ;
541+ }
542+
520543 // 其他指令(可能是 mov 等,对数据段符号的引用)引用了符号，由于不用考虑指令重写的问题,所以直接写入 0(%rip),让重定位阶段去找改符号进行重定位即可
521544 // 完全不用考虑是标签符号还是数据符号
522545 // 添加到重定位表(.rela.text)
@@ -527,15 +550,21 @@ static inline void elf_amd64_operation_encodings(elf_context_t *ctx, slice_t *cl
527550 Elf64_Sym sym = {
528551 .st_shndx = 0 ,
529552 .st_size = 0 ,
530- .st_info = ELF64_ST_INFO (STB_GLOBAL , STT_FUNC ),
553+ .st_info = ELF64_ST_INFO (STB_GLOBAL , st_type ),
531554 .st_other = 0 ,
532555 .st_value = 0 ,
533556 };
534557 sym_index = elf_put_sym (ctx -> symtab_section , ctx -> symtab_hash , & sym , symbol_operand -> name );
535558 }
536559
537- // rewrite symbol TODO 可能有其他的重定位方式
538- amd64_rewrite_rip_symbol (rel_operand );
560+ int reloc_type = 0 ;
561+ if (symbol_operand -> is_tls ) {
562+ amd64_rewrite_fs_offset_symbol (rel_operand );
563+ reloc_type = R_X86_64_TPOFF32 ;
564+ } else {
565+ amd64_rewrite_rip_symbol (rel_operand );
566+ reloc_type = R_X86_64_PC32 ;
567+ }
539568
540569 // 编码
541570 temp -> inst = amd64_asm_inst_encoding (* operation , temp -> data , & temp -> data_count , c );
@@ -544,12 +573,18 @@ static inline void elf_amd64_operation_encodings(elf_context_t *ctx, slice_t *cl
544573
545574 // 将符号和 sym_index 关联,rel 记录了符号的使用位置， sym_index 记录的符号的信息(包括 linker 完成后的绝对虚拟地址)
546575 // 计算重定位的起点信息
576+ // rip_offset 和 seg_offset 都是最后 4 个字节
547577 uint64_t rel_offset = * temp -> offset + rip_offset (temp -> data_count , temp -> operation );
548- int64_t addend = (int64_t ) (* temp -> offset + temp -> data_count ) - (int64_t ) rel_offset ;
578+ int64_t addend = 0 ;
579+ if (symbol_operand -> is_tls ) {
580+ addend = 0 ;
581+ } else {
582+ addend = (int64_t ) (* temp -> offset + temp -> data_count ) - (int64_t ) rel_offset ;
583+ }
549584
550585 // addend = 下一条指令的起始位置 - rel_offset
551586 temp -> rel = elf_put_relocate (ctx , ctx -> symtab_section , ctx -> text_section ,
552- rel_offset , R_X86_64_PC32 , (int ) sym_index , - addend );
587+ rel_offset , reloc_type , (int ) sym_index , - addend );
553588
554589 continue ;
555590 }
@@ -679,7 +714,9 @@ static void mach_amd64_operation_encodings(mach_context_t *ctx, slice_t *closure
679714 if (!s -> is_local ) {
680715 n_type |= N_EXT ;
681716 }
682- uint64_t sym_index = mach_put_sym (ctx -> symtab_command , & (struct nlist_64 ){.n_sect = ctx -> text_section -> sh_index , .n_value = * temp -> offset , .n_type = n_type }, s -> name );
717+ uint64_t sym_index = mach_put_sym (ctx -> symtab_command ,
718+ & (struct nlist_64 ) {.n_sect = ctx -> text_section -> sh_index , .n_value = * temp -> offset , .n_type = n_type },
719+ s -> name );
683720 temp -> sym_index = sym_index ;
684721
685722 assert (s -> name );
@@ -722,7 +759,11 @@ static void mach_amd64_operation_encodings(mach_context_t *ctx, slice_t *closure
722759 uint64_t sym_index = (uint64_t ) table_get (symtab_hash , symbol_operand -> name );
723760 if (sym_index == 0 ) {
724761 // 可重定位符号注册
725- sym_index = mach_put_sym (ctx -> symtab_command , & (struct nlist_64 ){.n_sect = NO_SECT , .n_value = 0 , .n_type = N_UNDF | N_EXT }, symbol_operand -> name );
762+ sym_index = mach_put_sym (ctx -> symtab_command , & (struct nlist_64 ) {
763+ .n_sect = NO_SECT ,
764+ .n_value = 0 ,
765+ .n_type = N_UNDF | N_EXT
766+ }, symbol_operand -> name );
726767 }
727768
728769 // rewrite symbol
@@ -738,8 +779,14 @@ static void mach_amd64_operation_encodings(mach_context_t *ctx, slice_t *closure
738779 uint64_t rel_offset = * temp -> offset + rip_offset (temp -> data_count , temp -> operation );
739780 int64_t addend = (int64_t ) (* temp -> offset + temp -> data_count ) - (int64_t ) rel_offset ; // 下一条指令的其实位置
740781
782+ bool is_tls = symbol_operand -> is_tls ;
783+ int reloc_type = X86_64_RELOC_BRANCH ;
784+ if (is_tls ) {
785+ reloc_type = X86_64_RELOC_TLV ;
786+ }
787+
741788 // addend = 下一条指令的起始位置 - rel_offset, 这是一条 branch 类型的数据
742- temp -> rel = mach_put_relocate (ctx , ctx -> text_section , rel_offset , X86_64_RELOC_BRANCH , sym_index );
789+ temp -> rel = mach_put_relocate (ctx , ctx -> text_section , rel_offset , reloc_type , sym_index );
743790 continue ;
744791 }
745792 }
@@ -786,7 +833,9 @@ static void mach_amd64_operation_encodings(mach_context_t *ctx, slice_t *closure
786833 if (sym_index == 0 ) {
787834 // 如果遍历没有找到符号则会添加一条 UND 符号信息到符号表中
788835 // 10: 0000000000000000 0 FUNC GLOBAL DEFAULT UND string_new
789- sym_index = mach_put_sym (ctx -> symtab_command , & (struct nlist_64 ){.n_sect = NO_SECT , .n_value = 0 , .n_type = N_UNDF | N_EXT }, temp -> rel_symbol );
836+ sym_index = mach_put_sym (ctx -> symtab_command ,
837+ & (struct nlist_64 ) {.n_sect = NO_SECT , .n_value = 0 , .n_type = N_UNDF | N_EXT },
838+ temp -> rel_symbol );
790839 }
791840
792841 // sym->st_value 表示符号定义的位置，基于符号所在的 section(.section)
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