1 /*- 2 * Copyright (c) 2014, 2015 The FreeBSD Foundation. 3 * Copyright (c) 2014 Andrew Turner. 4 * All rights reserved. 5 * 6 * This software was developed by Andrew Turner under 7 * sponsorship from the FreeBSD Foundation. 8 * 9 * Portions of this software were developed by Konstantin Belousov 10 * under sponsorship from the FreeBSD Foundation. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/kernel.h> 39 #include <sys/systm.h> 40 #include <sys/exec.h> 41 #include <sys/imgact.h> 42 #include <sys/linker.h> 43 #include <sys/proc.h> 44 #include <sys/reg.h> 45 #include <sys/sysent.h> 46 #include <sys/imgact_elf.h> 47 #include <sys/syscall.h> 48 #include <sys/signalvar.h> 49 #include <sys/vnode.h> 50 51 #include <vm/vm.h> 52 #include <vm/vm_param.h> 53 54 #include <machine/elf.h> 55 #include <machine/md_var.h> 56 57 #include "linker_if.h" 58 59 u_long __read_frequently elf_hwcap; 60 u_long __read_frequently elf_hwcap2; 61 62 struct arm64_addr_mask elf64_addr_mask; 63 64 static struct sysentvec elf64_freebsd_sysvec = { 65 .sv_size = SYS_MAXSYSCALL, 66 .sv_table = sysent, 67 .sv_transtrap = NULL, 68 .sv_fixup = __elfN(freebsd_fixup), 69 .sv_sendsig = sendsig, 70 .sv_sigcode = sigcode, 71 .sv_szsigcode = &szsigcode, 72 .sv_name = "FreeBSD ELF64", 73 .sv_coredump = __elfN(coredump), 74 .sv_elf_core_osabi = ELFOSABI_FREEBSD, 75 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR, 76 .sv_elf_core_prepare_notes = __elfN(prepare_notes), 77 .sv_imgact_try = NULL, 78 .sv_minsigstksz = MINSIGSTKSZ, 79 .sv_minuser = VM_MIN_ADDRESS, 80 .sv_maxuser = VM_MAXUSER_ADDRESS, 81 .sv_usrstack = USRSTACK, 82 .sv_psstrings = PS_STRINGS, 83 .sv_psstringssz = sizeof(struct ps_strings), 84 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE, 85 .sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs), 86 .sv_copyout_strings = exec_copyout_strings, 87 .sv_setregs = exec_setregs, 88 .sv_fixlimit = NULL, 89 .sv_maxssiz = NULL, 90 .sv_flags = SV_SHP | SV_TIMEKEEP | SV_ABI_FREEBSD | SV_LP64 | 91 SV_ASLR | SV_RNG_SEED_VER, 92 .sv_set_syscall_retval = cpu_set_syscall_retval, 93 .sv_fetch_syscall_args = cpu_fetch_syscall_args, 94 .sv_syscallnames = syscallnames, 95 .sv_shared_page_base = SHAREDPAGE, 96 .sv_shared_page_len = PAGE_SIZE, 97 .sv_schedtail = NULL, 98 .sv_thread_detach = NULL, 99 .sv_trap = NULL, 100 .sv_hwcap = &elf_hwcap, 101 .sv_hwcap2 = &elf_hwcap2, 102 .sv_onexec_old = exec_onexec_old, 103 .sv_onexit = exit_onexit, 104 .sv_regset_begin = SET_BEGIN(__elfN(regset)), 105 .sv_regset_end = SET_LIMIT(__elfN(regset)), 106 }; 107 INIT_SYSENTVEC(elf64_sysvec, &elf64_freebsd_sysvec); 108 109 static Elf64_Brandinfo freebsd_brand_info = { 110 .brand = ELFOSABI_FREEBSD, 111 .machine = EM_AARCH64, 112 .compat_3_brand = "FreeBSD", 113 .emul_path = NULL, 114 .interp_path = "/libexec/ld-elf.so.1", 115 .sysvec = &elf64_freebsd_sysvec, 116 .interp_newpath = NULL, 117 .brand_note = &elf64_freebsd_brandnote, 118 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 119 }; 120 121 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST, 122 (sysinit_cfunc_t)elf64_insert_brand_entry, &freebsd_brand_info); 123 124 static bool 125 get_arm64_addr_mask(struct regset *rs, struct thread *td, void *buf, 126 size_t *sizep) 127 { 128 if (buf != NULL) { 129 KASSERT(*sizep == sizeof(elf64_addr_mask), 130 ("%s: invalid size", __func__)); 131 memcpy(buf, &elf64_addr_mask, sizeof(elf64_addr_mask)); 132 } 133 *sizep = sizeof(elf64_addr_mask); 134 135 return (true); 136 } 137 138 static struct regset regset_arm64_addr_mask = { 139 .note = NT_ARM_ADDR_MASK, 140 .size = sizeof(struct arm64_addr_mask), 141 .get = get_arm64_addr_mask, 142 }; 143 ELF_REGSET(regset_arm64_addr_mask); 144 145 void 146 elf64_dump_thread(struct thread *td, void *dst, size_t *off) 147 { 148 struct arm64_addr_mask addr_mask; 149 size_t len, mask_size; 150 151 len = 0; 152 if (dst != NULL) { 153 mask_size = sizeof(addr_mask); 154 get_arm64_addr_mask(®set_arm64_addr_mask, td, &addr_mask, 155 &mask_size); 156 157 len += elf64_populate_note(NT_ARM_ADDR_MASK, &addr_mask, dst, 158 sizeof(addr_mask), NULL); 159 } else { 160 len += elf64_populate_note(NT_ARM_ADDR_MASK, NULL, NULL, 161 sizeof(addr_mask), NULL); 162 } 163 164 *off += len; 165 } 166 167 bool 168 elf_is_ifunc_reloc(Elf_Size r_info __unused) 169 { 170 171 return (ELF_R_TYPE(r_info) == R_AARCH64_IRELATIVE); 172 } 173 174 static int 175 reloc_instr_imm(Elf32_Addr *where, Elf_Addr val, u_int msb, u_int lsb) 176 { 177 178 /* Check bounds: upper bits must be all ones or all zeros. */ 179 if ((uint64_t)((int64_t)val >> (msb + 1)) + 1 > 1) 180 return (-1); 181 val >>= lsb; 182 val &= (1 << (msb - lsb + 1)) - 1; 183 *where |= (Elf32_Addr)val; 184 return (0); 185 } 186 187 /* 188 * Process a relocation. Support for some static relocations is required 189 * in order for the -zifunc-noplt optimization to work. 190 */ 191 static int 192 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 193 int type, int flags, elf_lookup_fn lookup) 194 { 195 #define ARM64_ELF_RELOC_LOCAL (1 << 0) 196 #define ARM64_ELF_RELOC_LATE_IFUNC (1 << 1) 197 Elf_Addr *where, addr, addend, val; 198 Elf_Word rtype, symidx; 199 const Elf_Rel *rel; 200 const Elf_Rela *rela; 201 int error; 202 203 switch (type) { 204 case ELF_RELOC_REL: 205 rel = (const Elf_Rel *)data; 206 where = (Elf_Addr *) (relocbase + rel->r_offset); 207 addend = *where; 208 rtype = ELF_R_TYPE(rel->r_info); 209 symidx = ELF_R_SYM(rel->r_info); 210 break; 211 case ELF_RELOC_RELA: 212 rela = (const Elf_Rela *)data; 213 where = (Elf_Addr *) (relocbase + rela->r_offset); 214 addend = rela->r_addend; 215 rtype = ELF_R_TYPE(rela->r_info); 216 symidx = ELF_R_SYM(rela->r_info); 217 break; 218 default: 219 panic("unknown reloc type %d\n", type); 220 } 221 222 if ((flags & ARM64_ELF_RELOC_LATE_IFUNC) != 0) { 223 KASSERT(type == ELF_RELOC_RELA, 224 ("Only RELA ifunc relocations are supported")); 225 if (rtype != R_AARCH64_IRELATIVE) 226 return (0); 227 } 228 229 if ((flags & ARM64_ELF_RELOC_LOCAL) != 0) { 230 if (rtype == R_AARCH64_RELATIVE) 231 *where = elf_relocaddr(lf, relocbase + addend); 232 return (0); 233 } 234 235 error = 0; 236 switch (rtype) { 237 case R_AARCH64_NONE: 238 case R_AARCH64_RELATIVE: 239 break; 240 case R_AARCH64_TSTBR14: 241 error = lookup(lf, symidx, 1, &addr); 242 if (error != 0) 243 return (-1); 244 error = reloc_instr_imm((Elf32_Addr *)where, 245 addr + addend - (Elf_Addr)where, 15, 2); 246 break; 247 case R_AARCH64_CONDBR19: 248 error = lookup(lf, symidx, 1, &addr); 249 if (error != 0) 250 return (-1); 251 error = reloc_instr_imm((Elf32_Addr *)where, 252 addr + addend - (Elf_Addr)where, 20, 2); 253 break; 254 case R_AARCH64_JUMP26: 255 case R_AARCH64_CALL26: 256 error = lookup(lf, symidx, 1, &addr); 257 if (error != 0) 258 return (-1); 259 error = reloc_instr_imm((Elf32_Addr *)where, 260 addr + addend - (Elf_Addr)where, 27, 2); 261 break; 262 case R_AARCH64_ABS64: 263 case R_AARCH64_GLOB_DAT: 264 case R_AARCH64_JUMP_SLOT: 265 error = lookup(lf, symidx, 1, &addr); 266 if (error != 0) 267 return (-1); 268 *where = addr + addend; 269 break; 270 case R_AARCH64_IRELATIVE: 271 addr = relocbase + addend; 272 val = ((Elf64_Addr (*)(void))addr)(); 273 if (*where != val) 274 *where = val; 275 break; 276 default: 277 printf("kldload: unexpected relocation type %d, " 278 "symbol index %d\n", rtype, symidx); 279 return (-1); 280 } 281 return (error); 282 } 283 284 int 285 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 286 int type, elf_lookup_fn lookup) 287 { 288 289 return (elf_reloc_internal(lf, relocbase, data, type, 290 ARM64_ELF_RELOC_LOCAL, lookup)); 291 } 292 293 /* Process one elf relocation with addend. */ 294 int 295 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 296 elf_lookup_fn lookup) 297 { 298 299 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 300 } 301 302 int 303 elf_reloc_late(linker_file_t lf, Elf_Addr relocbase, const void *data, 304 int type, elf_lookup_fn lookup) 305 { 306 307 return (elf_reloc_internal(lf, relocbase, data, type, 308 ARM64_ELF_RELOC_LATE_IFUNC, lookup)); 309 } 310 311 int 312 elf_cpu_load_file(linker_file_t lf) 313 { 314 315 if (lf->id != 1) 316 cpu_icache_sync_range((vm_offset_t)lf->address, lf->size); 317 return (0); 318 } 319 320 int 321 elf_cpu_unload_file(linker_file_t lf __unused) 322 { 323 324 return (0); 325 } 326 327 int 328 elf_cpu_parse_dynamic(caddr_t loadbase __unused, Elf_Dyn *dynamic __unused) 329 { 330 331 return (0); 332 } 333