elf_machdep.c revision 293490
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 293490 2016-01-09 14:53:08Z dchagin $"); 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 .sv_thread_detach = NULL, 86}; 87INIT_SYSENTVEC(elf64_sysvec, &elf64_freebsd_sysvec); 88 89static Elf64_Brandinfo freebsd_brand_info = { 90 .brand = ELFOSABI_FREEBSD, 91 .machine = EM_X86_64, 92 .compat_3_brand = "FreeBSD", 93 .emul_path = NULL, 94 .interp_path = "/libexec/ld-elf.so.1", 95 .sysvec = &elf64_freebsd_sysvec, 96 .interp_newpath = NULL, 97 .brand_note = &elf64_freebsd_brandnote, 98 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 99}; 100 101SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST, 102 (sysinit_cfunc_t) elf64_insert_brand_entry, 103 &freebsd_brand_info); 104 105static Elf64_Brandinfo freebsd_brand_oinfo = { 106 .brand = ELFOSABI_FREEBSD, 107 .machine = EM_X86_64, 108 .compat_3_brand = "FreeBSD", 109 .emul_path = NULL, 110 .interp_path = "/usr/libexec/ld-elf.so.1", 111 .sysvec = &elf64_freebsd_sysvec, 112 .interp_newpath = NULL, 113 .brand_note = &elf64_freebsd_brandnote, 114 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 115}; 116 117SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY, 118 (sysinit_cfunc_t) elf64_insert_brand_entry, 119 &freebsd_brand_oinfo); 120 121static Elf64_Brandinfo kfreebsd_brand_info = { 122 .brand = ELFOSABI_FREEBSD, 123 .machine = EM_X86_64, 124 .compat_3_brand = "FreeBSD", 125 .emul_path = NULL, 126 .interp_path = "/lib/ld-kfreebsd-x86-64.so.1", 127 .sysvec = &elf64_freebsd_sysvec, 128 .interp_newpath = NULL, 129 .brand_note = &elf64_kfreebsd_brandnote, 130 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE_MANDATORY 131}; 132 133SYSINIT(kelf64, SI_SUB_EXEC, SI_ORDER_ANY, 134 (sysinit_cfunc_t) elf64_insert_brand_entry, 135 &kfreebsd_brand_info); 136 137void 138elf64_dump_thread(struct thread *td, void *dst, size_t *off) 139{ 140 void *buf; 141 size_t len; 142 143 len = 0; 144 if (use_xsave) { 145 if (dst != NULL) { 146 fpugetregs(td); 147 len += elf64_populate_note(NT_X86_XSTATE, 148 get_pcb_user_save_td(td), dst, 149 cpu_max_ext_state_size, &buf); 150 *(uint64_t *)((char *)buf + X86_XSTATE_XCR0_OFFSET) = 151 xsave_mask; 152 } else 153 len += elf64_populate_note(NT_X86_XSTATE, NULL, NULL, 154 cpu_max_ext_state_size, NULL); 155 } 156 *off = len; 157} 158 159/* Process one elf relocation with addend. */ 160static int 161elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 162 int type, int local, elf_lookup_fn lookup) 163{ 164 Elf64_Addr *where, val; 165 Elf32_Addr *where32, val32; 166 Elf_Addr addr; 167 Elf_Addr addend; 168 Elf_Size rtype, symidx; 169 const Elf_Rel *rel; 170 const Elf_Rela *rela; 171 int error; 172 173 switch (type) { 174 case ELF_RELOC_REL: 175 rel = (const Elf_Rel *)data; 176 where = (Elf_Addr *) (relocbase + rel->r_offset); 177 rtype = ELF_R_TYPE(rel->r_info); 178 symidx = ELF_R_SYM(rel->r_info); 179 /* Addend is 32 bit on 32 bit relocs */ 180 switch (rtype) { 181 case R_X86_64_PC32: 182 case R_X86_64_32S: 183 addend = *(Elf32_Addr *)where; 184 break; 185 default: 186 addend = *where; 187 break; 188 } 189 break; 190 case ELF_RELOC_RELA: 191 rela = (const Elf_Rela *)data; 192 where = (Elf_Addr *) (relocbase + rela->r_offset); 193 addend = rela->r_addend; 194 rtype = ELF_R_TYPE(rela->r_info); 195 symidx = ELF_R_SYM(rela->r_info); 196 break; 197 default: 198 panic("unknown reloc type %d\n", type); 199 } 200 201 switch (rtype) { 202 203 case R_X86_64_NONE: /* none */ 204 break; 205 206 case R_X86_64_64: /* S + A */ 207 error = lookup(lf, symidx, 1, &addr); 208 val = addr + addend; 209 if (error != 0) 210 return -1; 211 if (*where != val) 212 *where = val; 213 break; 214 215 case R_X86_64_PC32: /* S + A - P */ 216 error = lookup(lf, symidx, 1, &addr); 217 where32 = (Elf32_Addr *)where; 218 val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where); 219 if (error != 0) 220 return -1; 221 if (*where32 != val32) 222 *where32 = val32; 223 break; 224 225 case R_X86_64_32S: /* S + A sign extend */ 226 error = lookup(lf, symidx, 1, &addr); 227 val32 = (Elf32_Addr)(addr + addend); 228 where32 = (Elf32_Addr *)where; 229 if (error != 0) 230 return -1; 231 if (*where32 != val32) 232 *where32 = val32; 233 break; 234 235 case R_X86_64_COPY: /* none */ 236 /* 237 * There shouldn't be copy relocations in kernel 238 * objects. 239 */ 240 printf("kldload: unexpected R_COPY relocation\n"); 241 return -1; 242 break; 243 244 case R_X86_64_GLOB_DAT: /* S */ 245 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */ 246 error = lookup(lf, symidx, 1, &addr); 247 if (error != 0) 248 return -1; 249 if (*where != addr) 250 *where = addr; 251 break; 252 253 case R_X86_64_RELATIVE: /* B + A */ 254 addr = relocbase + addend; 255 val = addr; 256 if (*where != val) 257 *where = val; 258 break; 259 260 default: 261 printf("kldload: unexpected relocation type %ld\n", 262 rtype); 263 return -1; 264 } 265 return(0); 266} 267 268int 269elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 270 elf_lookup_fn lookup) 271{ 272 273 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 274} 275 276int 277elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 278 int type, elf_lookup_fn lookup) 279{ 280 281 return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup)); 282} 283 284int 285elf_cpu_load_file(linker_file_t lf __unused) 286{ 287 288 return (0); 289} 290 291int 292elf_cpu_unload_file(linker_file_t lf __unused) 293{ 294 295 return (0); 296} 297