diff options
Diffstat (limited to 'sysdeps/aarch64/dl-machine.h')
| -rw-r--r-- | sysdeps/aarch64/dl-machine.h | 255 |
1 files changed, 137 insertions, 118 deletions
diff --git a/sysdeps/aarch64/dl-machine.h b/sysdeps/aarch64/dl-machine.h index 282805e396..4935aa7c54 100644 --- a/sysdeps/aarch64/dl-machine.h +++ b/sysdeps/aarch64/dl-machine.h @@ -1,4 +1,4 @@ -/* Copyright (C) 1995-2016 Free Software Foundation, Inc. +/* Copyright (C) 1995-2018 Free Software Foundation, Inc. This file is part of the GNU C Library. @@ -21,9 +21,11 @@ #define ELF_MACHINE_NAME "aarch64" +#include <sysdep.h> #include <tls.h> #include <dl-tlsdesc.h> #include <dl-irel.h> +#include <cpu-features.c> /* Return nonzero iff ELF header is compatible with the running host. */ static inline int __attribute__ ((unused)) @@ -49,26 +51,11 @@ elf_machine_load_address (void) /* To figure out the load address we use the definition that for any symbol: dynamic_addr(symbol) = static_addr(symbol) + load_addr - The choice of symbol is arbitrary. The static address we obtain - by constructing a non GOT reference to the symbol, the dynamic - address of the symbol we compute using adrp/add to compute the - symbol's address relative to the PC. - This depends on 32bit relocations being resolved at link time - and that the static address fits in the 32bits. */ - - ElfW(Addr) static_addr; - ElfW(Addr) dynamic_addr; - - asm (" \n" -" adrp %1, _dl_start; \n" -" add %1, %1, #:lo12:_dl_start \n" -" ldr %w0, 1f \n" -" b 2f \n" -"1: \n" -" .word _dl_start \n" -"2: \n" - : "=r" (static_addr), "=r" (dynamic_addr)); - return dynamic_addr - static_addr; + _DYNAMIC sysmbol is used here as its link-time address stored in + the special unrelocated first GOT entry. */ + + extern ElfW(Dyn) _DYNAMIC[] attribute_hidden; + return (ElfW(Addr)) &_DYNAMIC - elf_machine_dynamic (); } /* Set up the loaded object described by L so its unrelocated PLT @@ -115,97 +102,117 @@ elf_machine_runtime_setup (struct link_map *l, int lazy, int profile) } } - if (l->l_info[ADDRIDX (DT_TLSDESC_GOT)] && lazy) - *(ElfW(Addr)*)(D_PTR (l, l_info[ADDRIDX (DT_TLSDESC_GOT)]) + l->l_addr) - = (ElfW(Addr)) &_dl_tlsdesc_resolve_rela; - return lazy; } /* Initial entry point for the dynamic linker. The C function _dl_start is the real entry point, its return value is the user program's entry point */ +#ifdef __LP64__ +# define RTLD_START RTLD_START_1 ("x", "3", "sp") +#else +# define RTLD_START RTLD_START_1 ("w", "2", "wsp") +#endif -#define RTLD_START asm ("\ -.text \n\ -.globl _start \n\ -.type _start, %function \n\ -.globl _dl_start_user \n\ -.type _dl_start_user, %function \n\ -_start: \n\ - mov x0, sp \n\ - bl _dl_start \n\ - // returns user entry point in x0 \n\ - mov x21, x0 \n\ -_dl_start_user: \n\ - // get the original arg count \n\ - ldr x1, [sp] \n\ - // get the argv address \n\ - add x2, sp, #8 \n\ - // get _dl_skip_args to see if we were \n\ - // invoked as an executable \n\ - adrp x4, _dl_skip_args \n\ - ldr w4, [x4, #:lo12:_dl_skip_args] \n\ - // do we need to adjust argc/argv \n\ - cmp w4, 0 \n\ - beq .L_done_stack_adjust \n\ - // subtract _dl_skip_args from original arg count \n\ - sub x1, x1, x4 \n\ - // store adjusted argc back to stack \n\ - str x1, [sp] \n\ - // find the first unskipped argument \n\ - mov x3, x2 \n\ - add x4, x2, x4, lsl #3 \n\ - // shuffle argv down \n\ -1: ldr x5, [x4], #8 \n\ - str x5, [x3], #8 \n\ - cmp x5, #0 \n\ - bne 1b \n\ - // shuffle envp down \n\ -1: ldr x5, [x4], #8 \n\ - str x5, [x3], #8 \n\ - cmp x5, #0 \n\ - bne 1b \n\ - // shuffle auxv down \n\ -1: ldp x0, x5, [x4, #16]! \n\ - stp x0, x5, [x3], #16 \n\ - cmp x0, #0 \n\ - bne 1b \n\ - // Update _dl_argv \n\ - adrp x3, _dl_argv \n\ - str x2, [x3, #:lo12:_dl_argv] \n\ -.L_done_stack_adjust: \n\ - // compute envp \n\ - add x3, x2, x1, lsl #3 \n\ - add x3, x3, #8 \n\ - adrp x16, _rtld_local \n\ - add x16, x16, #:lo12:_rtld_local \n\ - ldr x0, [x16] \n\ - bl _dl_init \n\ - // load the finalizer function \n\ - adrp x0, _dl_fini \n\ - add x0, x0, #:lo12:_dl_fini \n\ - // jump to the user_s entry point \n\ - br x21 \n\ + +#define RTLD_START_1(PTR, PTR_SIZE_LOG, PTR_SP) asm ("\ +.text \n\ +.globl _start \n\ +.type _start, %function \n\ +.globl _dl_start_user \n\ +.type _dl_start_user, %function \n\ +_start: \n\ + mov " PTR "0, " PTR_SP " \n\ + bl _dl_start \n\ + // returns user entry point in x0 \n\ + mov x21, x0 \n\ +_dl_start_user: \n\ + // get the original arg count \n\ + ldr " PTR "1, [sp] \n\ + // get the argv address \n\ + add " PTR "2, " PTR_SP ", #(1<<" PTR_SIZE_LOG ") \n\ + // get _dl_skip_args to see if we were \n\ + // invoked as an executable \n\ + adrp x4, _dl_skip_args \n\ + ldr w4, [x4, #:lo12:_dl_skip_args] \n\ + // do we need to adjust argc/argv \n\ + cmp w4, 0 \n\ + beq .L_done_stack_adjust \n\ + // subtract _dl_skip_args from original arg count \n\ + sub " PTR "1, " PTR "1, " PTR "4 \n\ + // store adjusted argc back to stack \n\ + str " PTR "1, [sp] \n\ + // find the first unskipped argument \n\ + mov " PTR "3, " PTR "2 \n\ + add " PTR "4, " PTR "2, " PTR "4, lsl #" PTR_SIZE_LOG " \n\ + // shuffle argv down \n\ +1: ldr " PTR "5, [x4], #(1<<" PTR_SIZE_LOG ") \n\ + str " PTR "5, [x3], #(1<<" PTR_SIZE_LOG ") \n\ + cmp " PTR "5, #0 \n\ + bne 1b \n\ + // shuffle envp down \n\ +1: ldr " PTR "5, [x4], #(1<<" PTR_SIZE_LOG ") \n\ + str " PTR "5, [x3], #(1<<" PTR_SIZE_LOG ") \n\ + cmp " PTR "5, #0 \n\ + bne 1b \n\ + // shuffle auxv down \n\ +1: ldp " PTR "0, " PTR "5, [x4, #(2<<" PTR_SIZE_LOG ")]! \n\ + stp " PTR "0, " PTR "5, [x3], #(2<<" PTR_SIZE_LOG ") \n\ + cmp " PTR "0, #0 \n\ + bne 1b \n\ + // Update _dl_argv \n\ + adrp x3, __GI__dl_argv \n\ + str " PTR "2, [x3, #:lo12:__GI__dl_argv] \n\ +.L_done_stack_adjust: \n\ + // compute envp \n\ + add " PTR "3, " PTR "2, " PTR "1, lsl #" PTR_SIZE_LOG " \n\ + add " PTR "3, " PTR "3, #(1<<" PTR_SIZE_LOG ") \n\ + adrp x16, _rtld_local \n\ + add " PTR "16, " PTR "16, #:lo12:_rtld_local \n\ + ldr " PTR "0, [x16] \n\ + bl _dl_init \n\ + // load the finalizer function \n\ + adrp x0, _dl_fini \n\ + add " PTR "0, " PTR "0, #:lo12:_dl_fini \n\ + // jump to the user_s entry point \n\ + br x21 \n\ "); #define elf_machine_type_class(type) \ - ((((type) == R_AARCH64_JUMP_SLOT || \ - (type) == R_AARCH64_TLS_DTPMOD || \ - (type) == R_AARCH64_TLS_DTPREL || \ - (type) == R_AARCH64_TLS_TPREL || \ - (type) == R_AARCH64_TLSDESC) * ELF_RTYPE_CLASS_PLT) \ - | (((type) == R_AARCH64_COPY) * ELF_RTYPE_CLASS_COPY) \ - | (((type) == R_AARCH64_GLOB_DAT) * ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA)) + ((((type) == AARCH64_R(JUMP_SLOT) \ + || (type) == AARCH64_R(TLS_DTPMOD) \ + || (type) == AARCH64_R(TLS_DTPREL) \ + || (type) == AARCH64_R(TLS_TPREL) \ + || (type) == AARCH64_R(TLSDESC)) * ELF_RTYPE_CLASS_PLT) \ + | (((type) == AARCH64_R(COPY)) * ELF_RTYPE_CLASS_COPY) \ + | (((type) == AARCH64_R(GLOB_DAT)) * ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA)) -#define ELF_MACHINE_JMP_SLOT R_AARCH64_JUMP_SLOT +#define ELF_MACHINE_JMP_SLOT AARCH64_R(JUMP_SLOT) /* AArch64 uses RELA not REL */ #define ELF_MACHINE_NO_REL 1 #define ELF_MACHINE_NO_RELA 0 +#define DL_PLATFORM_INIT dl_platform_init () + +static inline void __attribute__ ((unused)) +dl_platform_init (void) +{ + if (GLRO(dl_platform) != NULL && *GLRO(dl_platform) == '\0') + /* Avoid an empty string which would disturb us. */ + GLRO(dl_platform) = NULL; + +#ifdef SHARED + /* init_cpu_features has been called early from __libc_start_main in + static executable. */ + init_cpu_features (&GLRO(dl_aarch64_cpu_features)); +#endif +} + + static inline ElfW(Addr) elf_machine_fixup_plt (struct link_map *map, lookup_t t, + const ElfW(Sym) *refsym, const ElfW(Sym) *sym, const ElfW(Rela) *reloc, ElfW(Addr) *reloc_addr, ElfW(Addr) value) @@ -237,9 +244,9 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, void *const reloc_addr_arg, int skip_ifunc) { ElfW(Addr) *const reloc_addr = reloc_addr_arg; - const unsigned int r_type = ELF64_R_TYPE (reloc->r_info); + const unsigned int r_type = ELFW (R_TYPE) (reloc->r_info); - if (__builtin_expect (r_type == R_AARCH64_RELATIVE, 0)) + if (__builtin_expect (r_type == AARCH64_R(RELATIVE), 0)) *reloc_addr = map->l_addr + reloc->r_addend; else if (__builtin_expect (r_type == R_AARCH64_NONE, 0)) return; @@ -247,7 +254,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, { const ElfW(Sym) *const refsym = sym; struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type); - ElfW(Addr) value = sym_map == NULL ? 0 : sym_map->l_addr + sym->st_value; + ElfW(Addr) value = SYMBOL_ADDRESS (sym_map, sym, true); if (sym != NULL && __glibc_unlikely (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC) @@ -257,7 +264,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, switch (r_type) { - case R_AARCH64_COPY: + case AARCH64_R(COPY): if (sym == NULL) break; @@ -272,18 +279,21 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, RTLD_PROGNAME, strtab + refsym->st_name); } memcpy (reloc_addr_arg, (void *) value, - MIN (sym->st_size, refsym->st_size)); + sym->st_size < refsym->st_size + ? sym->st_size : refsym->st_size); break; - case R_AARCH64_RELATIVE: - case R_AARCH64_GLOB_DAT: - case R_AARCH64_JUMP_SLOT: - case R_AARCH64_ABS32: - case R_AARCH64_ABS64: + case AARCH64_R(RELATIVE): + case AARCH64_R(GLOB_DAT): + case AARCH64_R(JUMP_SLOT): + case AARCH64_R(ABS32): +#ifdef __LP64__ + case AARCH64_R(ABS64): +#endif *reloc_addr = value + reloc->r_addend; break; - case R_AARCH64_TLSDESC: + case AARCH64_R(TLSDESC): { struct tlsdesc volatile *td = (struct tlsdesc volatile *)reloc_addr; @@ -318,7 +328,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, break; } - case R_AARCH64_TLS_DTPMOD: + case AARCH64_R(TLS_DTPMOD): #ifdef RTLD_BOOTSTRAP *reloc_addr = 1; #else @@ -329,12 +339,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, #endif break; - case R_AARCH64_TLS_DTPREL: + case AARCH64_R(TLS_DTPREL): if (sym) *reloc_addr = sym->st_value + reloc->r_addend; break; - case R_AARCH64_TLS_TPREL: + case AARCH64_R(TLS_TPREL): if (sym) { CHECK_STATIC_TLS (map, sym_map); @@ -343,7 +353,7 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, } break; - case R_AARCH64_IRELATIVE: + case AARCH64_R(IRELATIVE): value = map->l_addr + reloc->r_addend; value = elf_ifunc_invoke (value); *reloc_addr = value; @@ -374,25 +384,34 @@ elf_machine_lazy_rel (struct link_map *map, int skip_ifunc) { ElfW(Addr) *const reloc_addr = (void *) (l_addr + reloc->r_offset); - const unsigned int r_type = ELF64_R_TYPE (reloc->r_info); + const unsigned int r_type = ELFW (R_TYPE) (reloc->r_info); /* Check for unexpected PLT reloc type. */ - if (__builtin_expect (r_type == R_AARCH64_JUMP_SLOT, 1)) + if (__builtin_expect (r_type == AARCH64_R(JUMP_SLOT), 1)) { if (__builtin_expect (map->l_mach.plt, 0) == 0) *reloc_addr += l_addr; else *reloc_addr = map->l_mach.plt; } - else if (__builtin_expect (r_type == R_AARCH64_TLSDESC, 1)) + else if (__builtin_expect (r_type == AARCH64_R(TLSDESC), 1)) { - struct tlsdesc volatile *td = - (struct tlsdesc volatile *)reloc_addr; + const Elf_Symndx symndx = ELFW (R_SYM) (reloc->r_info); + const ElfW (Sym) *symtab = (const void *)D_PTR (map, l_info[DT_SYMTAB]); + const ElfW (Sym) *sym = &symtab[symndx]; + const struct r_found_version *version = NULL; + + if (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL) + { + const ElfW (Half) *vernum = + (const void *)D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]); + version = &map->l_versions[vernum[symndx] & 0x7fff]; + } - td->arg = (void*)reloc; - td->entry = (void*)(D_PTR (map, l_info[ADDRIDX (DT_TLSDESC_PLT)]) - + map->l_addr); + /* Always initialize TLS descriptors completely, because lazy + initialization requires synchronization at every TLS access. */ + elf_machine_rela (map, reloc, sym, version, reloc_addr, skip_ifunc); } - else if (__glibc_unlikely (r_type == R_AARCH64_IRELATIVE)) + else if (__glibc_unlikely (r_type == AARCH64_R(IRELATIVE))) { ElfW(Addr) value = map->l_addr + reloc->r_addend; if (__glibc_likely (!skip_ifunc)) |