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/param.h> 35 #include <sys/kernel.h> 36 #include <sys/systm.h> 37 #include <sys/exec.h> 38 #include <sys/imgact.h> 39 #include <sys/linker.h> 40 #include <sys/proc.h> 41 #include <sys/reg.h> 42 #include <sys/sysent.h> 43 #include <sys/imgact_elf.h> 44 #include <sys/syscall.h> 45 #include <sys/signalvar.h> 46 #include <sys/vnode.h> 47 48 #include <vm/vm.h> 49 #include <vm/vm_param.h> 50 51 #include <machine/elf.h> 52 #include <machine/md_var.h> 53 54 #include "linker_if.h" 55 56 u_long __read_frequently elf_hwcap; 57 u_long __read_frequently elf_hwcap2; 58 /* TODO: Move to a better location */ 59 u_long __read_frequently linux_elf_hwcap; 60 u_long __read_frequently linux_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_fixup = __elfN(freebsd_fixup), 68 .sv_sendsig = sendsig, 69 .sv_sigcode = sigcode, 70 .sv_szsigcode = &szsigcode, 71 .sv_name = "FreeBSD ELF64", 72 .sv_coredump = __elfN(coredump), 73 .sv_elf_core_osabi = ELFOSABI_FREEBSD, 74 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR, 75 .sv_elf_core_prepare_notes = __elfN(prepare_notes), 76 .sv_minsigstksz = MINSIGSTKSZ, 77 .sv_minuser = VM_MIN_ADDRESS, 78 .sv_maxuser = VM_MAXUSER_ADDRESS, 79 .sv_usrstack = USRSTACK, 80 .sv_psstrings = PS_STRINGS, 81 .sv_psstringssz = sizeof(struct ps_strings), 82 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE, 83 .sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs), 84 .sv_copyout_strings = exec_copyout_strings, 85 .sv_setregs = exec_setregs, 86 .sv_fixlimit = NULL, 87 .sv_maxssiz = NULL, 88 .sv_flags = SV_SHP | SV_TIMEKEEP | SV_ABI_FREEBSD | SV_LP64 | 89 SV_ASLR | SV_RNG_SEED_VER | SV_SIGSYS, 90 .sv_set_syscall_retval = cpu_set_syscall_retval, 91 .sv_fetch_syscall_args = cpu_fetch_syscall_args, 92 .sv_syscallnames = syscallnames, 93 .sv_shared_page_base = SHAREDPAGE, 94 .sv_shared_page_len = PAGE_SIZE, 95 .sv_schedtail = NULL, 96 .sv_thread_detach = NULL, 97 .sv_trap = NULL, 98 .sv_hwcap = &elf_hwcap, 99 .sv_hwcap2 = &elf_hwcap2, 100 .sv_onexec_old = exec_onexec_old, 101 .sv_onexit = exit_onexit, 102 .sv_regset_begin = SET_BEGIN(__elfN(regset)), 103 .sv_regset_end = SET_LIMIT(__elfN(regset)), 104 }; 105 INIT_SYSENTVEC(elf64_sysvec, &elf64_freebsd_sysvec); 106 107 static Elf64_Brandinfo freebsd_brand_info = { 108 .brand = ELFOSABI_FREEBSD, 109 .machine = EM_AARCH64, 110 .compat_3_brand = "FreeBSD", 111 .interp_path = "/libexec/ld-elf.so.1", 112 .sysvec = &elf64_freebsd_sysvec, 113 .interp_newpath = NULL, 114 .brand_note = &elf64_freebsd_brandnote, 115 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 116 }; 117 118 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST, 119 (sysinit_cfunc_t)elf64_insert_brand_entry, &freebsd_brand_info); 120 121 static bool 122 get_arm64_addr_mask(struct regset *rs, struct thread *td, void *buf, 123 size_t *sizep) 124 { 125 if (buf != NULL) { 126 KASSERT(*sizep == sizeof(elf64_addr_mask), 127 ("%s: invalid size", __func__)); 128 memcpy(buf, &elf64_addr_mask, sizeof(elf64_addr_mask)); 129 } 130 *sizep = sizeof(elf64_addr_mask); 131 132 return (true); 133 } 134 135 static struct regset regset_arm64_addr_mask = { 136 .note = NT_ARM_ADDR_MASK, 137 .size = sizeof(struct arm64_addr_mask), 138 .get = get_arm64_addr_mask, 139 }; 140 ELF_REGSET(regset_arm64_addr_mask); 141 142 void 143 elf64_dump_thread(struct thread *td __unused, void *dst __unused, 144 size_t *off __unused) 145 { 146 } 147 148 bool 149 elf_is_ifunc_reloc(Elf_Size r_info __unused) 150 { 151 152 return (ELF_R_TYPE(r_info) == R_AARCH64_IRELATIVE); 153 } 154 155 static int 156 reloc_instr_imm(Elf32_Addr *where, Elf_Addr val, u_int msb, u_int lsb) 157 { 158 159 /* Check bounds: upper bits must be all ones or all zeros. */ 160 if ((uint64_t)((int64_t)val >> (msb + 1)) + 1 > 1) 161 return (-1); 162 val >>= lsb; 163 val &= (1 << (msb - lsb + 1)) - 1; 164 *where |= (Elf32_Addr)val; 165 return (0); 166 } 167 168 /* 169 * Process a relocation. Support for some static relocations is required 170 * in order for the -zifunc-noplt optimization to work. 171 */ 172 static int 173 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 174 int type, int flags, elf_lookup_fn lookup) 175 { 176 #define ARM64_ELF_RELOC_LOCAL (1 << 0) 177 #define ARM64_ELF_RELOC_LATE_IFUNC (1 << 1) 178 Elf_Addr *where, addr, addend, val; 179 Elf_Word rtype, symidx; 180 const Elf_Rel *rel; 181 const Elf_Rela *rela; 182 int error; 183 184 switch (type) { 185 case ELF_RELOC_REL: 186 rel = (const Elf_Rel *)data; 187 where = (Elf_Addr *) (relocbase + rel->r_offset); 188 addend = *where; 189 rtype = ELF_R_TYPE(rel->r_info); 190 symidx = ELF_R_SYM(rel->r_info); 191 break; 192 case ELF_RELOC_RELA: 193 rela = (const Elf_Rela *)data; 194 where = (Elf_Addr *) (relocbase + rela->r_offset); 195 addend = rela->r_addend; 196 rtype = ELF_R_TYPE(rela->r_info); 197 symidx = ELF_R_SYM(rela->r_info); 198 break; 199 default: 200 panic("unknown reloc type %d\n", type); 201 } 202 203 if ((flags & ARM64_ELF_RELOC_LATE_IFUNC) != 0) { 204 KASSERT(type == ELF_RELOC_RELA, 205 ("Only RELA ifunc relocations are supported")); 206 if (rtype != R_AARCH64_IRELATIVE) 207 return (0); 208 } 209 210 if ((flags & ARM64_ELF_RELOC_LOCAL) != 0) { 211 if (rtype == R_AARCH64_RELATIVE) 212 *where = elf_relocaddr(lf, relocbase + addend); 213 return (0); 214 } 215 216 error = 0; 217 switch (rtype) { 218 case R_AARCH64_NONE: 219 case R_AARCH64_RELATIVE: 220 break; 221 case R_AARCH64_TSTBR14: 222 error = lookup(lf, symidx, 1, &addr); 223 if (error != 0) 224 return (-1); 225 error = reloc_instr_imm((Elf32_Addr *)where, 226 addr + addend - (Elf_Addr)where, 15, 2); 227 break; 228 case R_AARCH64_CONDBR19: 229 error = lookup(lf, symidx, 1, &addr); 230 if (error != 0) 231 return (-1); 232 error = reloc_instr_imm((Elf32_Addr *)where, 233 addr + addend - (Elf_Addr)where, 20, 2); 234 break; 235 case R_AARCH64_JUMP26: 236 case R_AARCH64_CALL26: 237 error = lookup(lf, symidx, 1, &addr); 238 if (error != 0) 239 return (-1); 240 error = reloc_instr_imm((Elf32_Addr *)where, 241 addr + addend - (Elf_Addr)where, 27, 2); 242 break; 243 case R_AARCH64_ABS64: 244 case R_AARCH64_GLOB_DAT: 245 case R_AARCH64_JUMP_SLOT: 246 error = lookup(lf, symidx, 1, &addr); 247 if (error != 0) 248 return (-1); 249 *where = addr + addend; 250 break; 251 case R_AARCH64_IRELATIVE: 252 addr = relocbase + addend; 253 val = ((Elf64_Addr (*)(void))addr)(); 254 if (*where != val) 255 *where = val; 256 break; 257 default: 258 printf("kldload: unexpected relocation type %d, " 259 "symbol index %d\n", rtype, symidx); 260 return (-1); 261 } 262 return (error); 263 } 264 265 int 266 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 267 int type, elf_lookup_fn lookup) 268 { 269 270 return (elf_reloc_internal(lf, relocbase, data, type, 271 ARM64_ELF_RELOC_LOCAL, lookup)); 272 } 273 274 /* Process one elf relocation with addend. */ 275 int 276 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 277 elf_lookup_fn lookup) 278 { 279 280 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 281 } 282 283 int 284 elf_reloc_late(linker_file_t lf, Elf_Addr relocbase, const void *data, 285 int type, elf_lookup_fn lookup) 286 { 287 288 return (elf_reloc_internal(lf, relocbase, data, type, 289 ARM64_ELF_RELOC_LATE_IFUNC, lookup)); 290 } 291 292 int 293 elf_cpu_load_file(linker_file_t lf) 294 { 295 296 if (lf->id != 1) 297 cpu_icache_sync_range((vm_offset_t)lf->address, lf->size); 298 return (0); 299 } 300 301 int 302 elf_cpu_unload_file(linker_file_t lf __unused) 303 { 304 305 return (0); 306 } 307 308 int 309 elf_cpu_parse_dynamic(caddr_t loadbase __unused, Elf_Dyn *dynamic __unused) 310 { 311 312 return (0); 313 } 314