elf_machdep.c revision 279211
1/*- 2 * Copyright 1996-1998 John D. Polstra. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include <sys/cdefs.h> 27__FBSDID("$FreeBSD: stable/10/sys/amd64/amd64/elf_machdep.c 279211 2015-02-23 18:38:41Z jhb $"); 28 29#include <sys/param.h> 30#include <sys/kernel.h> 31#include <sys/systm.h> 32#include <sys/exec.h> 33#include <sys/imgact.h> 34#include <sys/linker.h> 35#include <sys/proc.h> 36#include <sys/sysent.h> 37#include <sys/imgact_elf.h> 38#include <sys/syscall.h> 39#include <sys/signalvar.h> 40#include <sys/vnode.h> 41 42#include <vm/vm.h> 43#include <vm/pmap.h> 44#include <vm/vm_param.h> 45 46#include <machine/elf.h> 47#include <machine/fpu.h> 48#include <machine/md_var.h> 49 50struct sysentvec elf64_freebsd_sysvec = { 51 .sv_size = SYS_MAXSYSCALL, 52 .sv_table = sysent, 53 .sv_mask = 0, 54 .sv_sigsize = 0, 55 .sv_sigtbl = NULL, 56 .sv_errsize = 0, 57 .sv_errtbl = NULL, 58 .sv_transtrap = NULL, 59 .sv_fixup = __elfN(freebsd_fixup), 60 .sv_sendsig = sendsig, 61 .sv_sigcode = sigcode, 62 .sv_szsigcode = &szsigcode, 63 .sv_prepsyscall = NULL, 64 .sv_name = "FreeBSD ELF64", 65 .sv_coredump = __elfN(coredump), 66 .sv_imgact_try = NULL, 67 .sv_minsigstksz = MINSIGSTKSZ, 68 .sv_pagesize = PAGE_SIZE, 69 .sv_minuser = VM_MIN_ADDRESS, 70 .sv_maxuser = VM_MAXUSER_ADDRESS, 71 .sv_usrstack = USRSTACK, 72 .sv_psstrings = PS_STRINGS, 73 .sv_stackprot = VM_PROT_ALL, 74 .sv_copyout_strings = exec_copyout_strings, 75 .sv_setregs = exec_setregs, 76 .sv_fixlimit = NULL, 77 .sv_maxssiz = NULL, 78 .sv_flags = SV_ABI_FREEBSD | SV_LP64 | SV_SHP, 79 .sv_set_syscall_retval = cpu_set_syscall_retval, 80 .sv_fetch_syscall_args = cpu_fetch_syscall_args, 81 .sv_syscallnames = syscallnames, 82 .sv_shared_page_base = SHAREDPAGE, 83 .sv_shared_page_len = PAGE_SIZE, 84 .sv_schedtail = NULL, 85}; 86INIT_SYSENTVEC(elf64_sysvec, &elf64_freebsd_sysvec); 87 88static Elf64_Brandinfo freebsd_brand_info = { 89 .brand = ELFOSABI_FREEBSD, 90 .machine = EM_X86_64, 91 .compat_3_brand = "FreeBSD", 92 .emul_path = NULL, 93 .interp_path = "/libexec/ld-elf.so.1", 94 .sysvec = &elf64_freebsd_sysvec, 95 .interp_newpath = NULL, 96 .brand_note = &elf64_freebsd_brandnote, 97 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 98}; 99 100SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST, 101 (sysinit_cfunc_t) elf64_insert_brand_entry, 102 &freebsd_brand_info); 103 104static Elf64_Brandinfo freebsd_brand_oinfo = { 105 .brand = ELFOSABI_FREEBSD, 106 .machine = EM_X86_64, 107 .compat_3_brand = "FreeBSD", 108 .emul_path = NULL, 109 .interp_path = "/usr/libexec/ld-elf.so.1", 110 .sysvec = &elf64_freebsd_sysvec, 111 .interp_newpath = NULL, 112 .brand_note = &elf64_freebsd_brandnote, 113 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 114}; 115 116SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY, 117 (sysinit_cfunc_t) elf64_insert_brand_entry, 118 &freebsd_brand_oinfo); 119 120static Elf64_Brandinfo kfreebsd_brand_info = { 121 .brand = ELFOSABI_FREEBSD, 122 .machine = EM_X86_64, 123 .compat_3_brand = "FreeBSD", 124 .emul_path = NULL, 125 .interp_path = "/lib/ld-kfreebsd-x86-64.so.1", 126 .sysvec = &elf64_freebsd_sysvec, 127 .interp_newpath = NULL, 128 .brand_note = &elf64_kfreebsd_brandnote, 129 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE_MANDATORY 130}; 131 132SYSINIT(kelf64, SI_SUB_EXEC, SI_ORDER_ANY, 133 (sysinit_cfunc_t) elf64_insert_brand_entry, 134 &kfreebsd_brand_info); 135 136void 137elf64_dump_thread(struct thread *td, void *dst, size_t *off) 138{ 139 void *buf; 140 size_t len; 141 142 len = 0; 143 if (use_xsave) { 144 if (dst != NULL) { 145 fpugetregs(td); 146 len += elf64_populate_note(NT_X86_XSTATE, 147 get_pcb_user_save_td(td), dst, 148 cpu_max_ext_state_size, &buf); 149 *(uint64_t *)((char *)buf + X86_XSTATE_XCR0_OFFSET) = 150 xsave_mask; 151 } else 152 len += elf64_populate_note(NT_X86_XSTATE, NULL, NULL, 153 cpu_max_ext_state_size, NULL); 154 } 155 *off = len; 156} 157 158/* Process one elf relocation with addend. */ 159static int 160elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 161 int type, int local, elf_lookup_fn lookup) 162{ 163 Elf64_Addr *where, val; 164 Elf32_Addr *where32, val32; 165 Elf_Addr addr; 166 Elf_Addr addend; 167 Elf_Size rtype, symidx; 168 const Elf_Rel *rel; 169 const Elf_Rela *rela; 170 171 switch (type) { 172 case ELF_RELOC_REL: 173 rel = (const Elf_Rel *)data; 174 where = (Elf_Addr *) (relocbase + rel->r_offset); 175 rtype = ELF_R_TYPE(rel->r_info); 176 symidx = ELF_R_SYM(rel->r_info); 177 /* Addend is 32 bit on 32 bit relocs */ 178 switch (rtype) { 179 case R_X86_64_PC32: 180 case R_X86_64_32S: 181 addend = *(Elf32_Addr *)where; 182 break; 183 default: 184 addend = *where; 185 break; 186 } 187 break; 188 case ELF_RELOC_RELA: 189 rela = (const Elf_Rela *)data; 190 where = (Elf_Addr *) (relocbase + rela->r_offset); 191 addend = rela->r_addend; 192 rtype = ELF_R_TYPE(rela->r_info); 193 symidx = ELF_R_SYM(rela->r_info); 194 break; 195 default: 196 panic("unknown reloc type %d\n", type); 197 } 198 199 switch (rtype) { 200 201 case R_X86_64_NONE: /* none */ 202 break; 203 204 case R_X86_64_64: /* S + A */ 205 addr = lookup(lf, symidx, 1); 206 val = addr + addend; 207 if (addr == 0) 208 return -1; 209 if (*where != val) 210 *where = val; 211 break; 212 213 case R_X86_64_PC32: /* S + A - P */ 214 addr = lookup(lf, symidx, 1); 215 where32 = (Elf32_Addr *)where; 216 val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where); 217 if (addr == 0) 218 return -1; 219 if (*where32 != val32) 220 *where32 = val32; 221 break; 222 223 case R_X86_64_32S: /* S + A sign extend */ 224 addr = lookup(lf, symidx, 1); 225 val32 = (Elf32_Addr)(addr + addend); 226 where32 = (Elf32_Addr *)where; 227 if (addr == 0) 228 return -1; 229 if (*where32 != val32) 230 *where32 = val32; 231 break; 232 233 case R_X86_64_COPY: /* none */ 234 /* 235 * There shouldn't be copy relocations in kernel 236 * objects. 237 */ 238 printf("kldload: unexpected R_COPY relocation\n"); 239 return -1; 240 break; 241 242 case R_X86_64_GLOB_DAT: /* S */ 243 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */ 244 addr = lookup(lf, symidx, 1); 245 if (addr == 0) 246 return -1; 247 if (*where != addr) 248 *where = addr; 249 break; 250 251 case R_X86_64_RELATIVE: /* B + A */ 252 addr = relocbase + addend; 253 val = addr; 254 if (*where != val) 255 *where = val; 256 break; 257 258 default: 259 printf("kldload: unexpected relocation type %ld\n", 260 rtype); 261 return -1; 262 } 263 return(0); 264} 265 266int 267elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 268 elf_lookup_fn lookup) 269{ 270 271 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 272} 273 274int 275elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 276 int type, elf_lookup_fn lookup) 277{ 278 279 return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup)); 280} 281 282int 283elf_cpu_load_file(linker_file_t lf __unused) 284{ 285 286 return (0); 287} 288 289int 290elf_cpu_unload_file(linker_file_t lf __unused) 291{ 292 293 return (0); 294} 295