1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright 1996-1998 John D. Polstra. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30 #include <sys/param.h> 31 #include <sys/kernel.h> 32 #include <sys/systm.h> 33 34 #define __ELF_WORD_SIZE 32 35 36 #include <sys/exec.h> 37 #include <sys/imgact.h> 38 #include <sys/malloc.h> 39 #include <sys/proc.h> 40 #include <sys/namei.h> 41 #include <sys/fcntl.h> 42 #include <sys/sysent.h> 43 #include <sys/imgact_elf.h> 44 #include <sys/jail.h> 45 #include <sys/reg.h> 46 #include <sys/smp.h> 47 #include <sys/syscall.h> 48 #include <sys/sysctl.h> 49 #include <sys/signalvar.h> 50 #include <sys/vnode.h> 51 #include <sys/linker.h> 52 53 #include <vm/vm.h> 54 #include <vm/vm_param.h> 55 56 #include <machine/altivec.h> 57 #include <machine/cpu.h> 58 #include <machine/fpu.h> 59 #include <machine/elf.h> 60 #include <machine/md_var.h> 61 62 #include <powerpc/powerpc/elf_common.c> 63 64 #ifdef __powerpc64__ 65 #include <compat/freebsd32/freebsd32_proto.h> 66 #include <compat/freebsd32/freebsd32_util.h> 67 68 extern const char *freebsd32_syscallnames[]; 69 static void ppc32_fixlimit(struct rlimit *rl, int which); 70 71 static SYSCTL_NODE(_compat, OID_AUTO, ppc32, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 72 "32-bit mode"); 73 74 #define PPC32_MAXDSIZ (1024*1024*1024) 75 static u_long ppc32_maxdsiz = PPC32_MAXDSIZ; 76 SYSCTL_ULONG(_compat_ppc32, OID_AUTO, maxdsiz, CTLFLAG_RWTUN, &ppc32_maxdsiz, 77 0, ""); 78 #define PPC32_MAXSSIZ (64*1024*1024) 79 u_long ppc32_maxssiz = PPC32_MAXSSIZ; 80 SYSCTL_ULONG(_compat_ppc32, OID_AUTO, maxssiz, CTLFLAG_RWTUN, &ppc32_maxssiz, 81 0, ""); 82 #else 83 static void ppc32_runtime_resolve(void); 84 #endif 85 86 struct sysentvec elf32_freebsd_sysvec = { 87 .sv_size = SYS_MAXSYSCALL, 88 #ifdef __powerpc64__ 89 .sv_table = freebsd32_sysent, 90 #else 91 .sv_table = sysent, 92 #endif 93 .sv_fixup = __elfN(freebsd_fixup), 94 .sv_copyout_auxargs = __elfN(powerpc_copyout_auxargs), 95 .sv_sendsig = sendsig, 96 .sv_sigcode = sigcode32, 97 .sv_szsigcode = &szsigcode32, 98 .sv_name = "FreeBSD ELF32", 99 .sv_coredump = __elfN(coredump), 100 .sv_elf_core_osabi = ELFOSABI_FREEBSD, 101 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR, 102 .sv_elf_core_prepare_notes = __elfN(prepare_notes), 103 .sv_imgact_try = NULL, 104 .sv_minsigstksz = MINSIGSTKSZ, 105 .sv_minuser = VM_MIN_ADDRESS, 106 .sv_stackprot = VM_PROT_ALL, 107 #ifdef __powerpc64__ 108 .sv_maxuser = VM_MAXUSER_ADDRESS32, 109 .sv_usrstack = FREEBSD32_USRSTACK, 110 .sv_psstrings = FREEBSD32_PS_STRINGS, 111 .sv_psstringssz = sizeof(struct freebsd32_ps_strings), 112 .sv_copyout_strings = freebsd32_copyout_strings, 113 .sv_setregs = ppc32_setregs, 114 .sv_syscallnames = freebsd32_syscallnames, 115 .sv_fixlimit = ppc32_fixlimit, 116 #else 117 .sv_maxuser = VM_MAXUSER_ADDRESS, 118 .sv_usrstack = USRSTACK, 119 .sv_psstrings = PS_STRINGS, 120 .sv_psstringssz = sizeof(struct ps_strings), 121 .sv_copyout_strings = exec_copyout_strings, 122 .sv_setregs = exec_setregs, 123 .sv_syscallnames = syscallnames, 124 .sv_fixlimit = NULL, 125 #endif 126 .sv_maxssiz = NULL, 127 .sv_flags = SV_ABI_FREEBSD | SV_ILP32 | SV_SHP | SV_ASLR | 128 SV_TIMEKEEP | SV_RNG_SEED_VER, 129 .sv_set_syscall_retval = cpu_set_syscall_retval, 130 .sv_fetch_syscall_args = cpu_fetch_syscall_args, 131 .sv_shared_page_base = FREEBSD32_SHAREDPAGE, 132 .sv_shared_page_len = PAGE_SIZE, 133 .sv_schedtail = NULL, 134 .sv_thread_detach = NULL, 135 .sv_trap = NULL, 136 .sv_hwcap = &cpu_features, 137 .sv_hwcap2 = &cpu_features2, 138 .sv_onexec_old = exec_onexec_old, 139 .sv_onexit = exit_onexit, 140 .sv_regset_begin = SET_BEGIN(__elfN(regset)), 141 .sv_regset_end = SET_LIMIT(__elfN(regset)), 142 }; 143 INIT_SYSENTVEC(elf32_sysvec, &elf32_freebsd_sysvec); 144 145 static Elf32_Brandinfo freebsd_brand_info = { 146 .brand = ELFOSABI_FREEBSD, 147 .machine = EM_PPC, 148 .compat_3_brand = "FreeBSD", 149 .emul_path = NULL, 150 .interp_path = "/libexec/ld-elf.so.1", 151 .sysvec = &elf32_freebsd_sysvec, 152 #ifdef __powerpc64__ 153 .interp_newpath = "/libexec/ld-elf32.so.1", 154 #else 155 .interp_newpath = NULL, 156 #endif 157 .brand_note = &elf32_freebsd_brandnote, 158 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 159 }; 160 161 SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST, 162 (sysinit_cfunc_t) elf32_insert_brand_entry, 163 &freebsd_brand_info); 164 165 static Elf32_Brandinfo freebsd_brand_oinfo = { 166 .brand = ELFOSABI_FREEBSD, 167 .machine = EM_PPC, 168 .compat_3_brand = "FreeBSD", 169 .emul_path = NULL, 170 .interp_path = "/usr/libexec/ld-elf.so.1", 171 .sysvec = &elf32_freebsd_sysvec, 172 .interp_newpath = NULL, 173 .brand_note = &elf32_freebsd_brandnote, 174 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 175 }; 176 177 SYSINIT(oelf32, SI_SUB_EXEC, SI_ORDER_ANY, 178 (sysinit_cfunc_t) elf32_insert_brand_entry, 179 &freebsd_brand_oinfo); 180 181 void elf_reloc_self(Elf_Dyn *dynp, Elf_Addr relocbase); 182 183 void 184 elf32_dump_thread(struct thread *td, void *dst, size_t *off) 185 { 186 size_t len; 187 struct pcb *pcb; 188 uint64_t vshr[32]; 189 uint64_t *vsr_dw1; 190 int vsr_idx; 191 192 len = 0; 193 pcb = td->td_pcb; 194 195 if (pcb->pcb_flags & PCB_VEC) { 196 save_vec_nodrop(td); 197 if (dst != NULL) { 198 len += elf32_populate_note(NT_PPC_VMX, 199 &pcb->pcb_vec, (char *)dst + len, 200 sizeof(pcb->pcb_vec), NULL); 201 } else 202 len += elf32_populate_note(NT_PPC_VMX, NULL, NULL, 203 sizeof(pcb->pcb_vec), NULL); 204 } 205 206 if (pcb->pcb_flags & PCB_VSX) { 207 save_fpu_nodrop(td); 208 if (dst != NULL) { 209 /* 210 * Doubleword 0 of VSR0-VSR31 overlap with FPR0-FPR31 and 211 * VSR32-VSR63 overlap with VR0-VR31, so we only copy 212 * the non-overlapping data, which is doubleword 1 of VSR0-VSR31. 213 */ 214 for (vsr_idx = 0; vsr_idx < nitems(vshr); vsr_idx++) { 215 vsr_dw1 = (uint64_t *)&pcb->pcb_fpu.fpr[vsr_idx].vsr[2]; 216 vshr[vsr_idx] = *vsr_dw1; 217 } 218 len += elf32_populate_note(NT_PPC_VSX, 219 vshr, (char *)dst + len, 220 sizeof(vshr), NULL); 221 } else 222 len += elf32_populate_note(NT_PPC_VSX, NULL, NULL, 223 sizeof(vshr), NULL); 224 } 225 226 *off = len; 227 } 228 229 #ifndef __powerpc64__ 230 bool 231 elf_is_ifunc_reloc(Elf_Size r_info) 232 { 233 234 return (ELF_R_TYPE(r_info) == R_PPC_IRELATIVE); 235 } 236 237 /* Process one elf relocation with addend. */ 238 static int 239 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 240 int type, int local, elf_lookup_fn lookup) 241 { 242 Elf_Addr *where; 243 Elf_Half *hwhere; 244 Elf_Addr addr; 245 Elf_Addr addend, val; 246 Elf_Word rtype, symidx; 247 const Elf_Rela *rela; 248 int error; 249 250 switch (type) { 251 case ELF_RELOC_REL: 252 panic("PPC only supports RELA relocations"); 253 break; 254 case ELF_RELOC_RELA: 255 rela = (const Elf_Rela *)data; 256 where = (Elf_Addr *) ((uintptr_t)relocbase + rela->r_offset); 257 hwhere = (Elf_Half *) ((uintptr_t)relocbase + rela->r_offset); 258 addend = rela->r_addend; 259 rtype = ELF_R_TYPE(rela->r_info); 260 symidx = ELF_R_SYM(rela->r_info); 261 break; 262 default: 263 panic("elf_reloc: unknown relocation mode %d\n", type); 264 } 265 266 switch (rtype) { 267 case R_PPC_NONE: 268 break; 269 270 case R_PPC_ADDR32: /* word32 S + A */ 271 error = lookup(lf, symidx, 1, &addr); 272 if (error != 0) 273 return (-1); 274 *where = elf_relocaddr(lf, addr + addend); 275 break; 276 277 case R_PPC_ADDR16_LO: /* #lo(S) */ 278 error = lookup(lf, symidx, 1, &addr); 279 if (error != 0) 280 return (-1); 281 /* 282 * addend values are sometimes relative to sections 283 * (i.e. .rodata) in rela, where in reality they 284 * are relative to relocbase. Detect this condition. 285 */ 286 if (addr > relocbase && addr <= (relocbase + addend)) 287 addr = relocbase; 288 addr = elf_relocaddr(lf, addr + addend); 289 *hwhere = addr & 0xffff; 290 break; 291 292 case R_PPC_ADDR16_HA: /* #ha(S) */ 293 error = lookup(lf, symidx, 1, &addr); 294 if (error != 0) 295 return (-1); 296 /* 297 * addend values are sometimes relative to sections 298 * (i.e. .rodata) in rela, where in reality they 299 * are relative to relocbase. Detect this condition. 300 */ 301 if (addr > relocbase && addr <= (relocbase + addend)) 302 addr = relocbase; 303 addr = elf_relocaddr(lf, addr + addend); 304 *hwhere = ((addr >> 16) + ((addr & 0x8000) ? 1 : 0)) 305 & 0xffff; 306 break; 307 308 case R_PPC_RELATIVE: /* word32 B + A */ 309 *where = elf_relocaddr(lf, relocbase + addend); 310 break; 311 312 case R_PPC_JMP_SLOT: /* PLT jump slot entry */ 313 /* 314 * We currently only support Secure-PLT jump slots. 315 * Given that we reject BSS-PLT modules during load, we 316 * don't need to check again. 317 * The method we are using here is equivilent to 318 * LD_BIND_NOW. 319 */ 320 error = lookup(lf, symidx, 1, &addr); 321 if (error != 0) 322 return (-1); 323 *where = elf_relocaddr(lf, addr + addend); 324 break; 325 326 case R_PPC_IRELATIVE: 327 addr = relocbase + addend; 328 val = ((Elf32_Addr (*)(void))addr)(); 329 if (*where != val) 330 *where = val; 331 break; 332 333 default: 334 printf("kldload: unexpected relocation type %d, " 335 "symbol index %d\n", (int)rtype, symidx); 336 return (-1); 337 } 338 return (0); 339 } 340 341 void 342 elf_reloc_self(Elf_Dyn *dynp, Elf_Addr relocbase) 343 { 344 Elf_Rela *rela = NULL, *relalim; 345 Elf_Addr relasz = 0; 346 Elf_Addr *where; 347 348 /* 349 * Extract the rela/relasz values from the dynamic section 350 */ 351 for (; dynp->d_tag != DT_NULL; dynp++) { 352 switch (dynp->d_tag) { 353 case DT_RELA: 354 rela = (Elf_Rela *)(relocbase+dynp->d_un.d_ptr); 355 break; 356 case DT_RELASZ: 357 relasz = dynp->d_un.d_val; 358 break; 359 } 360 } 361 362 /* 363 * Relocate these values 364 */ 365 relalim = (Elf_Rela *)((caddr_t)rela + relasz); 366 for (; rela < relalim; rela++) { 367 if (ELF_R_TYPE(rela->r_info) != R_PPC_RELATIVE) 368 continue; 369 where = (Elf_Addr *)(relocbase + rela->r_offset); 370 *where = (Elf_Addr)(relocbase + rela->r_addend); 371 } 372 } 373 374 int 375 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 376 elf_lookup_fn lookup) 377 { 378 379 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 380 } 381 382 int 383 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 384 int type, elf_lookup_fn lookup) 385 { 386 387 return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup)); 388 } 389 390 int 391 elf_cpu_load_file(linker_file_t lf) 392 { 393 394 /* Only sync the cache for non-kernel modules */ 395 if (lf->id != 1) 396 __syncicache(lf->address, lf->size); 397 return (0); 398 } 399 400 int 401 elf_cpu_unload_file(linker_file_t lf __unused) 402 { 403 404 return (0); 405 } 406 407 static void 408 ppc32_runtime_resolve() 409 { 410 411 /* 412 * Since we don't support lazy binding, panic immediately if anyone 413 * manages to call the runtime resolver. 414 */ 415 panic("kldload: Runtime resolver was called unexpectedly!"); 416 } 417 418 int 419 elf_cpu_parse_dynamic(caddr_t loadbase, Elf_Dyn *dynamic) 420 { 421 Elf_Dyn *dp; 422 bool has_plt = false; 423 bool secure_plt = false; 424 Elf_Addr *got; 425 426 for (dp = dynamic; dp->d_tag != DT_NULL; dp++) { 427 switch (dp->d_tag) { 428 case DT_PPC_GOT: 429 secure_plt = true; 430 got = (Elf_Addr *)(loadbase + dp->d_un.d_ptr); 431 /* Install runtime resolver canary. */ 432 got[1] = (Elf_Addr)ppc32_runtime_resolve; 433 got[2] = (Elf_Addr)0; 434 break; 435 case DT_PLTGOT: 436 has_plt = true; 437 break; 438 } 439 } 440 441 if (has_plt && !secure_plt) { 442 printf("kldload: BSS-PLT modules are not supported.\n"); 443 return (-1); 444 } 445 return (0); 446 } 447 #endif 448 449 #ifdef __powerpc64__ 450 static void 451 ppc32_fixlimit(struct rlimit *rl, int which) 452 { 453 switch (which) { 454 case RLIMIT_DATA: 455 if (ppc32_maxdsiz != 0) { 456 if (rl->rlim_cur > ppc32_maxdsiz) 457 rl->rlim_cur = ppc32_maxdsiz; 458 if (rl->rlim_max > ppc32_maxdsiz) 459 rl->rlim_max = ppc32_maxdsiz; 460 } 461 break; 462 case RLIMIT_STACK: 463 if (ppc32_maxssiz != 0) { 464 if (rl->rlim_cur > ppc32_maxssiz) 465 rl->rlim_cur = ppc32_maxssiz; 466 if (rl->rlim_max > ppc32_maxssiz) 467 rl->rlim_max = ppc32_maxssiz; 468 } 469 break; 470 } 471 } 472 #endif 473