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 #include <vm/pmap.h> 56 #include <vm/vm_map.h> 57 58 #include <machine/altivec.h> 59 #include <machine/cpu.h> 60 #include <machine/fpu.h> 61 #include <machine/elf.h> 62 #include <machine/md_var.h> 63 64 #include <powerpc/powerpc/elf_common.c> 65 66 #ifdef __powerpc64__ 67 #include <compat/freebsd32/freebsd32_proto.h> 68 #include <compat/freebsd32/freebsd32_util.h> 69 70 extern const char *freebsd32_syscallnames[]; 71 static void ppc32_fixlimit(struct rlimit *rl, int which); 72 73 static SYSCTL_NODE(_compat, OID_AUTO, ppc32, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 74 "32-bit mode"); 75 76 #define PPC32_MAXDSIZ (1024*1024*1024) 77 static u_long ppc32_maxdsiz = PPC32_MAXDSIZ; 78 SYSCTL_ULONG(_compat_ppc32, OID_AUTO, maxdsiz, CTLFLAG_RWTUN, &ppc32_maxdsiz, 79 0, ""); 80 #define PPC32_MAXSSIZ (64*1024*1024) 81 u_long ppc32_maxssiz = PPC32_MAXSSIZ; 82 SYSCTL_ULONG(_compat_ppc32, OID_AUTO, maxssiz, CTLFLAG_RWTUN, &ppc32_maxssiz, 83 0, ""); 84 #else 85 static void ppc32_runtime_resolve(void); 86 #endif 87 88 struct sysentvec elf32_freebsd_sysvec = { 89 .sv_size = SYS_MAXSYSCALL, 90 #ifdef __powerpc64__ 91 .sv_table = freebsd32_sysent, 92 #else 93 .sv_table = sysent, 94 #endif 95 .sv_fixup = __elfN(freebsd_fixup), 96 .sv_copyout_auxargs = __elfN(powerpc_copyout_auxargs), 97 .sv_sendsig = sendsig, 98 .sv_sigcode = sigcode32, 99 .sv_szsigcode = &szsigcode32, 100 .sv_name = "FreeBSD ELF32", 101 .sv_coredump = __elfN(coredump), 102 .sv_elf_core_osabi = ELFOSABI_FREEBSD, 103 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR, 104 .sv_elf_core_prepare_notes = __elfN(prepare_notes), 105 .sv_imgact_try = NULL, 106 .sv_minsigstksz = MINSIGSTKSZ, 107 .sv_minuser = VM_MIN_ADDRESS, 108 .sv_stackprot = VM_PROT_ALL, 109 #ifdef __powerpc64__ 110 .sv_maxuser = VM_MAXUSER_ADDRESS32, 111 .sv_usrstack = FREEBSD32_USRSTACK, 112 .sv_psstrings = FREEBSD32_PS_STRINGS, 113 .sv_psstringssz = sizeof(struct freebsd32_ps_strings), 114 .sv_copyout_strings = freebsd32_copyout_strings, 115 .sv_setregs = ppc32_setregs, 116 .sv_syscallnames = freebsd32_syscallnames, 117 .sv_fixlimit = ppc32_fixlimit, 118 #else 119 .sv_maxuser = VM_MAXUSER_ADDRESS, 120 .sv_usrstack = USRSTACK, 121 .sv_psstrings = PS_STRINGS, 122 .sv_psstringssz = sizeof(struct ps_strings), 123 .sv_copyout_strings = exec_copyout_strings, 124 .sv_setregs = exec_setregs, 125 .sv_syscallnames = syscallnames, 126 .sv_fixlimit = NULL, 127 #endif 128 .sv_maxssiz = NULL, 129 .sv_flags = SV_ABI_FREEBSD | SV_ILP32 | SV_SHP | SV_ASLR | 130 SV_TIMEKEEP | SV_RNG_SEED_VER, 131 .sv_set_syscall_retval = cpu_set_syscall_retval, 132 .sv_fetch_syscall_args = cpu_fetch_syscall_args, 133 .sv_shared_page_base = FREEBSD32_SHAREDPAGE, 134 .sv_shared_page_len = PAGE_SIZE, 135 .sv_schedtail = NULL, 136 .sv_thread_detach = NULL, 137 .sv_trap = NULL, 138 .sv_hwcap = &cpu_features, 139 .sv_hwcap2 = &cpu_features2, 140 .sv_onexec_old = exec_onexec_old, 141 .sv_onexit = exit_onexit, 142 .sv_regset_begin = SET_BEGIN(__elfN(regset)), 143 .sv_regset_end = SET_LIMIT(__elfN(regset)), 144 }; 145 INIT_SYSENTVEC(elf32_sysvec, &elf32_freebsd_sysvec); 146 147 static Elf32_Brandinfo freebsd_brand_info = { 148 .brand = ELFOSABI_FREEBSD, 149 .machine = EM_PPC, 150 .compat_3_brand = "FreeBSD", 151 .emul_path = NULL, 152 .interp_path = "/libexec/ld-elf.so.1", 153 .sysvec = &elf32_freebsd_sysvec, 154 #ifdef __powerpc64__ 155 .interp_newpath = "/libexec/ld-elf32.so.1", 156 #else 157 .interp_newpath = NULL, 158 #endif 159 .brand_note = &elf32_freebsd_brandnote, 160 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 161 }; 162 163 SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST, 164 (sysinit_cfunc_t) elf32_insert_brand_entry, 165 &freebsd_brand_info); 166 167 static Elf32_Brandinfo freebsd_brand_oinfo = { 168 .brand = ELFOSABI_FREEBSD, 169 .machine = EM_PPC, 170 .compat_3_brand = "FreeBSD", 171 .emul_path = NULL, 172 .interp_path = "/usr/libexec/ld-elf.so.1", 173 .sysvec = &elf32_freebsd_sysvec, 174 .interp_newpath = NULL, 175 .brand_note = &elf32_freebsd_brandnote, 176 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 177 }; 178 179 SYSINIT(oelf32, SI_SUB_EXEC, SI_ORDER_ANY, 180 (sysinit_cfunc_t) elf32_insert_brand_entry, 181 &freebsd_brand_oinfo); 182 183 void elf_reloc_self(Elf_Dyn *dynp, Elf_Addr relocbase); 184 185 void 186 elf32_dump_thread(struct thread *td, void *dst, size_t *off) 187 { 188 size_t len; 189 struct pcb *pcb; 190 uint64_t vshr[32]; 191 uint64_t *vsr_dw1; 192 int vsr_idx; 193 194 len = 0; 195 pcb = td->td_pcb; 196 197 if (pcb->pcb_flags & PCB_VEC) { 198 save_vec_nodrop(td); 199 if (dst != NULL) { 200 len += elf32_populate_note(NT_PPC_VMX, 201 &pcb->pcb_vec, (char *)dst + len, 202 sizeof(pcb->pcb_vec), NULL); 203 } else 204 len += elf32_populate_note(NT_PPC_VMX, NULL, NULL, 205 sizeof(pcb->pcb_vec), NULL); 206 } 207 208 if (pcb->pcb_flags & PCB_VSX) { 209 save_fpu_nodrop(td); 210 if (dst != NULL) { 211 /* 212 * Doubleword 0 of VSR0-VSR31 overlap with FPR0-FPR31 and 213 * VSR32-VSR63 overlap with VR0-VR31, so we only copy 214 * the non-overlapping data, which is doubleword 1 of VSR0-VSR31. 215 */ 216 for (vsr_idx = 0; vsr_idx < nitems(vshr); vsr_idx++) { 217 vsr_dw1 = (uint64_t *)&pcb->pcb_fpu.fpr[vsr_idx].vsr[2]; 218 vshr[vsr_idx] = *vsr_dw1; 219 } 220 len += elf32_populate_note(NT_PPC_VSX, 221 vshr, (char *)dst + len, 222 sizeof(vshr), NULL); 223 } else 224 len += elf32_populate_note(NT_PPC_VSX, NULL, NULL, 225 sizeof(vshr), NULL); 226 } 227 228 *off = len; 229 } 230 231 #ifndef __powerpc64__ 232 bool 233 elf_is_ifunc_reloc(Elf_Size r_info) 234 { 235 236 return (ELF_R_TYPE(r_info) == R_PPC_IRELATIVE); 237 } 238 239 /* Process one elf relocation with addend. */ 240 static int 241 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 242 int type, int local, elf_lookup_fn lookup) 243 { 244 Elf_Addr *where; 245 Elf_Half *hwhere; 246 Elf_Addr addr; 247 Elf_Addr addend, val; 248 Elf_Word rtype, symidx; 249 const Elf_Rela *rela; 250 int error; 251 252 switch (type) { 253 case ELF_RELOC_REL: 254 panic("PPC only supports RELA relocations"); 255 break; 256 case ELF_RELOC_RELA: 257 rela = (const Elf_Rela *)data; 258 where = (Elf_Addr *) ((uintptr_t)relocbase + rela->r_offset); 259 hwhere = (Elf_Half *) ((uintptr_t)relocbase + rela->r_offset); 260 addend = rela->r_addend; 261 rtype = ELF_R_TYPE(rela->r_info); 262 symidx = ELF_R_SYM(rela->r_info); 263 break; 264 default: 265 panic("elf_reloc: unknown relocation mode %d\n", type); 266 } 267 268 switch (rtype) { 269 case R_PPC_NONE: 270 break; 271 272 case R_PPC_ADDR32: /* word32 S + A */ 273 error = lookup(lf, symidx, 1, &addr); 274 if (error != 0) 275 return (-1); 276 *where = elf_relocaddr(lf, addr + addend); 277 break; 278 279 case R_PPC_ADDR16_LO: /* #lo(S) */ 280 error = lookup(lf, symidx, 1, &addr); 281 if (error != 0) 282 return (-1); 283 /* 284 * addend values are sometimes relative to sections 285 * (i.e. .rodata) in rela, where in reality they 286 * are relative to relocbase. Detect this condition. 287 */ 288 if (addr > relocbase && addr <= (relocbase + addend)) 289 addr = relocbase; 290 addr = elf_relocaddr(lf, addr + addend); 291 *hwhere = addr & 0xffff; 292 break; 293 294 case R_PPC_ADDR16_HA: /* #ha(S) */ 295 error = lookup(lf, symidx, 1, &addr); 296 if (error != 0) 297 return (-1); 298 /* 299 * addend values are sometimes relative to sections 300 * (i.e. .rodata) in rela, where in reality they 301 * are relative to relocbase. Detect this condition. 302 */ 303 if (addr > relocbase && addr <= (relocbase + addend)) 304 addr = relocbase; 305 addr = elf_relocaddr(lf, addr + addend); 306 *hwhere = ((addr >> 16) + ((addr & 0x8000) ? 1 : 0)) 307 & 0xffff; 308 break; 309 310 case R_PPC_RELATIVE: /* word32 B + A */ 311 *where = elf_relocaddr(lf, relocbase + addend); 312 break; 313 314 case R_PPC_JMP_SLOT: /* PLT jump slot entry */ 315 /* 316 * We currently only support Secure-PLT jump slots. 317 * Given that we reject BSS-PLT modules during load, we 318 * don't need to check again. 319 * The method we are using here is equivilent to 320 * LD_BIND_NOW. 321 */ 322 error = lookup(lf, symidx, 1, &addr); 323 if (error != 0) 324 return (-1); 325 *where = elf_relocaddr(lf, addr + addend); 326 break; 327 328 case R_PPC_IRELATIVE: 329 addr = relocbase + addend; 330 val = ((Elf32_Addr (*)(void))addr)(); 331 if (*where != val) 332 *where = val; 333 break; 334 335 default: 336 printf("kldload: unexpected relocation type %d, " 337 "symbol index %d\n", (int)rtype, symidx); 338 return (-1); 339 } 340 return (0); 341 } 342 343 void 344 elf_reloc_self(Elf_Dyn *dynp, Elf_Addr relocbase) 345 { 346 Elf_Rela *rela = NULL, *relalim; 347 Elf_Addr relasz = 0; 348 Elf_Addr *where; 349 350 /* 351 * Extract the rela/relasz values from the dynamic section 352 */ 353 for (; dynp->d_tag != DT_NULL; dynp++) { 354 switch (dynp->d_tag) { 355 case DT_RELA: 356 rela = (Elf_Rela *)(relocbase+dynp->d_un.d_ptr); 357 break; 358 case DT_RELASZ: 359 relasz = dynp->d_un.d_val; 360 break; 361 } 362 } 363 364 /* 365 * Relocate these values 366 */ 367 relalim = (Elf_Rela *)((caddr_t)rela + relasz); 368 for (; rela < relalim; rela++) { 369 if (ELF_R_TYPE(rela->r_info) != R_PPC_RELATIVE) 370 continue; 371 where = (Elf_Addr *)(relocbase + rela->r_offset); 372 *where = (Elf_Addr)(relocbase + rela->r_addend); 373 } 374 } 375 376 int 377 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 378 elf_lookup_fn lookup) 379 { 380 381 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 382 } 383 384 int 385 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 386 int type, elf_lookup_fn lookup) 387 { 388 389 return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup)); 390 } 391 392 int 393 elf_cpu_load_file(linker_file_t lf) 394 { 395 396 /* Only sync the cache for non-kernel modules */ 397 if (lf->id != 1) 398 __syncicache(lf->address, lf->size); 399 return (0); 400 } 401 402 int 403 elf_cpu_unload_file(linker_file_t lf __unused) 404 { 405 406 return (0); 407 } 408 409 static void 410 ppc32_runtime_resolve() 411 { 412 413 /* 414 * Since we don't support lazy binding, panic immediately if anyone 415 * manages to call the runtime resolver. 416 */ 417 panic("kldload: Runtime resolver was called unexpectedly!"); 418 } 419 420 int 421 elf_cpu_parse_dynamic(caddr_t loadbase, Elf_Dyn *dynamic) 422 { 423 Elf_Dyn *dp; 424 bool has_plt = false; 425 bool secure_plt = false; 426 Elf_Addr *got; 427 428 for (dp = dynamic; dp->d_tag != DT_NULL; dp++) { 429 switch (dp->d_tag) { 430 case DT_PPC_GOT: 431 secure_plt = true; 432 got = (Elf_Addr *)(loadbase + dp->d_un.d_ptr); 433 /* Install runtime resolver canary. */ 434 got[1] = (Elf_Addr)ppc32_runtime_resolve; 435 got[2] = (Elf_Addr)0; 436 break; 437 case DT_PLTGOT: 438 has_plt = true; 439 break; 440 } 441 } 442 443 if (has_plt && !secure_plt) { 444 printf("kldload: BSS-PLT modules are not supported.\n"); 445 return (-1); 446 } 447 return (0); 448 } 449 #endif 450 451 #ifdef __powerpc64__ 452 static void 453 ppc32_fixlimit(struct rlimit *rl, int which) 454 { 455 switch (which) { 456 case RLIMIT_DATA: 457 if (ppc32_maxdsiz != 0) { 458 if (rl->rlim_cur > ppc32_maxdsiz) 459 rl->rlim_cur = ppc32_maxdsiz; 460 if (rl->rlim_max > ppc32_maxdsiz) 461 rl->rlim_max = ppc32_maxdsiz; 462 } 463 break; 464 case RLIMIT_STACK: 465 if (ppc32_maxssiz != 0) { 466 if (rl->rlim_cur > ppc32_maxssiz) 467 rl->rlim_cur = ppc32_maxssiz; 468 if (rl->rlim_max > ppc32_maxssiz) 469 rl->rlim_max = ppc32_maxssiz; 470 } 471 break; 472 } 473 } 474 #endif 475