1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* binfmt_elf_fdpic.c: FDPIC ELF binary format 3 * 4 * Copyright (C) 2003, 2004, 2006 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 * Derived from binfmt_elf.c 7 */ 8 9 #include <linux/module.h> 10 11 #include <linux/fs.h> 12 #include <linux/stat.h> 13 #include <linux/sched.h> 14 #include <linux/sched/coredump.h> 15 #include <linux/sched/task_stack.h> 16 #include <linux/sched/cputime.h> 17 #include <linux/mm.h> 18 #include <linux/mman.h> 19 #include <linux/errno.h> 20 #include <linux/signal.h> 21 #include <linux/binfmts.h> 22 #include <linux/string.h> 23 #include <linux/file.h> 24 #include <linux/fcntl.h> 25 #include <linux/slab.h> 26 #include <linux/pagemap.h> 27 #include <linux/security.h> 28 #include <linux/highmem.h> 29 #include <linux/highuid.h> 30 #include <linux/personality.h> 31 #include <linux/ptrace.h> 32 #include <linux/init.h> 33 #include <linux/elf.h> 34 #include <linux/elf-fdpic.h> 35 #include <linux/elfcore.h> 36 #include <linux/coredump.h> 37 #include <linux/dax.h> 38 #include <linux/regset.h> 39 40 #include <linux/uaccess.h> 41 #include <asm/param.h> 42 43 typedef char *elf_caddr_t; 44 45 #if 0 46 #define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ ) 47 #else 48 #define kdebug(fmt, ...) do {} while(0) 49 #endif 50 51 #if 0 52 #define kdcore(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ ) 53 #else 54 #define kdcore(fmt, ...) do {} while(0) 55 #endif 56 57 MODULE_LICENSE("GPL"); 58 59 static int load_elf_fdpic_binary(struct linux_binprm *); 60 static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *, struct file *); 61 static int elf_fdpic_map_file(struct elf_fdpic_params *, struct file *, 62 struct mm_struct *, const char *); 63 64 static int create_elf_fdpic_tables(struct linux_binprm *, struct mm_struct *, 65 struct elf_fdpic_params *, 66 struct elf_fdpic_params *); 67 68 #ifndef CONFIG_MMU 69 static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *, 70 struct file *, 71 struct mm_struct *); 72 #endif 73 74 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *, 75 struct file *, struct mm_struct *); 76 77 #ifdef CONFIG_ELF_CORE 78 static int elf_fdpic_core_dump(struct coredump_params *cprm); 79 #endif 80 81 static struct linux_binfmt elf_fdpic_format = { 82 .module = THIS_MODULE, 83 .load_binary = load_elf_fdpic_binary, 84 #ifdef CONFIG_ELF_CORE 85 .core_dump = elf_fdpic_core_dump, 86 .min_coredump = ELF_EXEC_PAGESIZE, 87 #endif 88 }; 89 90 static int __init init_elf_fdpic_binfmt(void) 91 { 92 register_binfmt(&elf_fdpic_format); 93 return 0; 94 } 95 96 static void __exit exit_elf_fdpic_binfmt(void) 97 { 98 unregister_binfmt(&elf_fdpic_format); 99 } 100 101 core_initcall(init_elf_fdpic_binfmt); 102 module_exit(exit_elf_fdpic_binfmt); 103 104 static int is_elf(struct elfhdr *hdr, struct file *file) 105 { 106 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0) 107 return 0; 108 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) 109 return 0; 110 if (!elf_check_arch(hdr)) 111 return 0; 112 if (!file->f_op->mmap) 113 return 0; 114 return 1; 115 } 116 117 #ifndef elf_check_fdpic 118 #define elf_check_fdpic(x) 0 119 #endif 120 121 #ifndef elf_check_const_displacement 122 #define elf_check_const_displacement(x) 0 123 #endif 124 125 static int is_constdisp(struct elfhdr *hdr) 126 { 127 if (!elf_check_fdpic(hdr)) 128 return 1; 129 if (elf_check_const_displacement(hdr)) 130 return 1; 131 return 0; 132 } 133 134 /*****************************************************************************/ 135 /* 136 * read the program headers table into memory 137 */ 138 static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params, 139 struct file *file) 140 { 141 struct elf32_phdr *phdr; 142 unsigned long size; 143 int retval, loop; 144 loff_t pos = params->hdr.e_phoff; 145 146 if (params->hdr.e_phentsize != sizeof(struct elf_phdr)) 147 return -ENOMEM; 148 if (params->hdr.e_phnum > 65536U / sizeof(struct elf_phdr)) 149 return -ENOMEM; 150 151 size = params->hdr.e_phnum * sizeof(struct elf_phdr); 152 params->phdrs = kmalloc(size, GFP_KERNEL); 153 if (!params->phdrs) 154 return -ENOMEM; 155 156 retval = kernel_read(file, params->phdrs, size, &pos); 157 if (unlikely(retval != size)) 158 return retval < 0 ? retval : -ENOEXEC; 159 160 /* determine stack size for this binary */ 161 phdr = params->phdrs; 162 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 163 if (phdr->p_type != PT_GNU_STACK) 164 continue; 165 166 if (phdr->p_flags & PF_X) 167 params->flags |= ELF_FDPIC_FLAG_EXEC_STACK; 168 else 169 params->flags |= ELF_FDPIC_FLAG_NOEXEC_STACK; 170 171 params->stack_size = phdr->p_memsz; 172 break; 173 } 174 175 return 0; 176 } 177 178 /*****************************************************************************/ 179 /* 180 * load an fdpic binary into various bits of memory 181 */ 182 static int load_elf_fdpic_binary(struct linux_binprm *bprm) 183 { 184 struct elf_fdpic_params exec_params, interp_params; 185 struct pt_regs *regs = current_pt_regs(); 186 struct elf_phdr *phdr; 187 unsigned long stack_size, entryaddr; 188 #ifdef ELF_FDPIC_PLAT_INIT 189 unsigned long dynaddr; 190 #endif 191 #ifndef CONFIG_MMU 192 unsigned long stack_prot; 193 #endif 194 struct file *interpreter = NULL; /* to shut gcc up */ 195 char *interpreter_name = NULL; 196 int executable_stack; 197 int retval, i; 198 loff_t pos; 199 200 kdebug("____ LOAD %d ____", current->pid); 201 202 memset(&exec_params, 0, sizeof(exec_params)); 203 memset(&interp_params, 0, sizeof(interp_params)); 204 205 exec_params.hdr = *(struct elfhdr *) bprm->buf; 206 exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE; 207 208 /* check that this is a binary we know how to deal with */ 209 retval = -ENOEXEC; 210 if (!is_elf(&exec_params.hdr, bprm->file)) 211 goto error; 212 if (!elf_check_fdpic(&exec_params.hdr)) { 213 #ifdef CONFIG_MMU 214 /* binfmt_elf handles non-fdpic elf except on nommu */ 215 goto error; 216 #else 217 /* nommu can only load ET_DYN (PIE) ELF */ 218 if (exec_params.hdr.e_type != ET_DYN) 219 goto error; 220 #endif 221 } 222 223 /* read the program header table */ 224 retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file); 225 if (retval < 0) 226 goto error; 227 228 /* scan for a program header that specifies an interpreter */ 229 phdr = exec_params.phdrs; 230 231 for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) { 232 switch (phdr->p_type) { 233 case PT_INTERP: 234 retval = -ENOMEM; 235 if (phdr->p_filesz > PATH_MAX) 236 goto error; 237 retval = -ENOENT; 238 if (phdr->p_filesz < 2) 239 goto error; 240 241 /* read the name of the interpreter into memory */ 242 interpreter_name = kmalloc(phdr->p_filesz, GFP_KERNEL); 243 if (!interpreter_name) 244 goto error; 245 246 pos = phdr->p_offset; 247 retval = kernel_read(bprm->file, interpreter_name, 248 phdr->p_filesz, &pos); 249 if (unlikely(retval != phdr->p_filesz)) { 250 if (retval >= 0) 251 retval = -ENOEXEC; 252 goto error; 253 } 254 255 retval = -ENOENT; 256 if (interpreter_name[phdr->p_filesz - 1] != '\0') 257 goto error; 258 259 kdebug("Using ELF interpreter %s", interpreter_name); 260 261 /* replace the program with the interpreter */ 262 interpreter = open_exec(interpreter_name); 263 retval = PTR_ERR(interpreter); 264 if (IS_ERR(interpreter)) { 265 interpreter = NULL; 266 goto error; 267 } 268 269 /* 270 * If the binary is not readable then enforce 271 * mm->dumpable = 0 regardless of the interpreter's 272 * permissions. 273 */ 274 would_dump(bprm, interpreter); 275 276 pos = 0; 277 retval = kernel_read(interpreter, bprm->buf, 278 BINPRM_BUF_SIZE, &pos); 279 if (unlikely(retval != BINPRM_BUF_SIZE)) { 280 if (retval >= 0) 281 retval = -ENOEXEC; 282 goto error; 283 } 284 285 interp_params.hdr = *((struct elfhdr *) bprm->buf); 286 break; 287 288 case PT_LOAD: 289 #ifdef CONFIG_MMU 290 if (exec_params.load_addr == 0) 291 exec_params.load_addr = phdr->p_vaddr; 292 #endif 293 break; 294 } 295 296 } 297 298 if (is_constdisp(&exec_params.hdr)) 299 exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP; 300 301 /* perform insanity checks on the interpreter */ 302 if (interpreter_name) { 303 retval = -ELIBBAD; 304 if (!is_elf(&interp_params.hdr, interpreter)) 305 goto error; 306 307 interp_params.flags = ELF_FDPIC_FLAG_PRESENT; 308 309 /* read the interpreter's program header table */ 310 retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter); 311 if (retval < 0) 312 goto error; 313 } 314 315 stack_size = exec_params.stack_size; 316 if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK) 317 executable_stack = EXSTACK_ENABLE_X; 318 else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK) 319 executable_stack = EXSTACK_DISABLE_X; 320 else 321 executable_stack = EXSTACK_DEFAULT; 322 323 if (stack_size == 0) { 324 stack_size = interp_params.stack_size; 325 if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK) 326 executable_stack = EXSTACK_ENABLE_X; 327 else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK) 328 executable_stack = EXSTACK_DISABLE_X; 329 else 330 executable_stack = EXSTACK_DEFAULT; 331 } 332 333 retval = -ENOEXEC; 334 if (stack_size == 0) 335 stack_size = 131072UL; /* same as exec.c's default commit */ 336 337 if (is_constdisp(&interp_params.hdr)) 338 interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP; 339 340 /* flush all traces of the currently running executable */ 341 retval = begin_new_exec(bprm); 342 if (retval) 343 goto error; 344 345 /* there's now no turning back... the old userspace image is dead, 346 * defunct, deceased, etc. 347 */ 348 if (elf_check_fdpic(&exec_params.hdr)) 349 set_personality(PER_LINUX_FDPIC); 350 else 351 set_personality(PER_LINUX); 352 if (elf_read_implies_exec(&exec_params.hdr, executable_stack)) 353 current->personality |= READ_IMPLIES_EXEC; 354 355 setup_new_exec(bprm); 356 357 set_binfmt(&elf_fdpic_format); 358 359 current->mm->start_code = 0; 360 current->mm->end_code = 0; 361 current->mm->start_stack = 0; 362 current->mm->start_data = 0; 363 current->mm->end_data = 0; 364 current->mm->context.exec_fdpic_loadmap = 0; 365 current->mm->context.interp_fdpic_loadmap = 0; 366 367 #ifdef CONFIG_MMU 368 elf_fdpic_arch_lay_out_mm(&exec_params, 369 &interp_params, 370 ¤t->mm->start_stack, 371 ¤t->mm->start_brk); 372 373 retval = setup_arg_pages(bprm, current->mm->start_stack, 374 executable_stack); 375 if (retval < 0) 376 goto error; 377 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES 378 retval = arch_setup_additional_pages(bprm, !!interpreter_name); 379 if (retval < 0) 380 goto error; 381 #endif 382 #endif 383 384 /* load the executable and interpreter into memory */ 385 retval = elf_fdpic_map_file(&exec_params, bprm->file, current->mm, 386 "executable"); 387 if (retval < 0) 388 goto error; 389 390 if (interpreter_name) { 391 retval = elf_fdpic_map_file(&interp_params, interpreter, 392 current->mm, "interpreter"); 393 if (retval < 0) { 394 printk(KERN_ERR "Unable to load interpreter\n"); 395 goto error; 396 } 397 398 allow_write_access(interpreter); 399 fput(interpreter); 400 interpreter = NULL; 401 } 402 403 #ifdef CONFIG_MMU 404 if (!current->mm->start_brk) 405 current->mm->start_brk = current->mm->end_data; 406 407 current->mm->brk = current->mm->start_brk = 408 PAGE_ALIGN(current->mm->start_brk); 409 410 #else 411 /* create a stack area and zero-size brk area */ 412 stack_size = (stack_size + PAGE_SIZE - 1) & PAGE_MASK; 413 if (stack_size < PAGE_SIZE * 2) 414 stack_size = PAGE_SIZE * 2; 415 416 stack_prot = PROT_READ | PROT_WRITE; 417 if (executable_stack == EXSTACK_ENABLE_X || 418 (executable_stack == EXSTACK_DEFAULT && VM_STACK_FLAGS & VM_EXEC)) 419 stack_prot |= PROT_EXEC; 420 421 current->mm->start_brk = vm_mmap(NULL, 0, stack_size, stack_prot, 422 MAP_PRIVATE | MAP_ANONYMOUS | 423 MAP_UNINITIALIZED | MAP_GROWSDOWN, 424 0); 425 426 if (IS_ERR_VALUE(current->mm->start_brk)) { 427 retval = current->mm->start_brk; 428 current->mm->start_brk = 0; 429 goto error; 430 } 431 432 current->mm->brk = current->mm->start_brk; 433 current->mm->context.end_brk = current->mm->start_brk; 434 current->mm->start_stack = current->mm->start_brk + stack_size; 435 #endif 436 437 retval = create_elf_fdpic_tables(bprm, current->mm, &exec_params, 438 &interp_params); 439 if (retval < 0) 440 goto error; 441 442 kdebug("- start_code %lx", current->mm->start_code); 443 kdebug("- end_code %lx", current->mm->end_code); 444 kdebug("- start_data %lx", current->mm->start_data); 445 kdebug("- end_data %lx", current->mm->end_data); 446 kdebug("- start_brk %lx", current->mm->start_brk); 447 kdebug("- brk %lx", current->mm->brk); 448 kdebug("- start_stack %lx", current->mm->start_stack); 449 450 #ifdef ELF_FDPIC_PLAT_INIT 451 /* 452 * The ABI may specify that certain registers be set up in special 453 * ways (on i386 %edx is the address of a DT_FINI function, for 454 * example. This macro performs whatever initialization to 455 * the regs structure is required. 456 */ 457 dynaddr = interp_params.dynamic_addr ?: exec_params.dynamic_addr; 458 ELF_FDPIC_PLAT_INIT(regs, exec_params.map_addr, interp_params.map_addr, 459 dynaddr); 460 #endif 461 462 finalize_exec(bprm); 463 /* everything is now ready... get the userspace context ready to roll */ 464 entryaddr = interp_params.entry_addr ?: exec_params.entry_addr; 465 start_thread(regs, entryaddr, current->mm->start_stack); 466 467 retval = 0; 468 469 error: 470 if (interpreter) { 471 allow_write_access(interpreter); 472 fput(interpreter); 473 } 474 kfree(interpreter_name); 475 kfree(exec_params.phdrs); 476 kfree(exec_params.loadmap); 477 kfree(interp_params.phdrs); 478 kfree(interp_params.loadmap); 479 return retval; 480 } 481 482 /*****************************************************************************/ 483 484 #ifndef ELF_BASE_PLATFORM 485 /* 486 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture. 487 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value 488 * will be copied to the user stack in the same manner as AT_PLATFORM. 489 */ 490 #define ELF_BASE_PLATFORM NULL 491 #endif 492 493 /* 494 * present useful information to the program by shovelling it onto the new 495 * process's stack 496 */ 497 static int create_elf_fdpic_tables(struct linux_binprm *bprm, 498 struct mm_struct *mm, 499 struct elf_fdpic_params *exec_params, 500 struct elf_fdpic_params *interp_params) 501 { 502 const struct cred *cred = current_cred(); 503 unsigned long sp, csp, nitems; 504 elf_caddr_t __user *argv, *envp; 505 size_t platform_len = 0, len; 506 char *k_platform, *k_base_platform; 507 char __user *u_platform, *u_base_platform, *p; 508 int loop; 509 int nr; /* reset for each csp adjustment */ 510 unsigned long flags = 0; 511 512 #ifdef CONFIG_MMU 513 /* In some cases (e.g. Hyper-Threading), we want to avoid L1 evictions 514 * by the processes running on the same package. One thing we can do is 515 * to shuffle the initial stack for them, so we give the architecture 516 * an opportunity to do so here. 517 */ 518 sp = arch_align_stack(bprm->p); 519 #else 520 sp = mm->start_stack; 521 522 /* stack the program arguments and environment */ 523 if (transfer_args_to_stack(bprm, &sp) < 0) 524 return -EFAULT; 525 sp &= ~15; 526 #endif 527 528 /* 529 * If this architecture has a platform capability string, copy it 530 * to userspace. In some cases (Sparc), this info is impossible 531 * for userspace to get any other way, in others (i386) it is 532 * merely difficult. 533 */ 534 k_platform = ELF_PLATFORM; 535 u_platform = NULL; 536 537 if (k_platform) { 538 platform_len = strlen(k_platform) + 1; 539 sp -= platform_len; 540 u_platform = (char __user *) sp; 541 if (copy_to_user(u_platform, k_platform, platform_len) != 0) 542 return -EFAULT; 543 } 544 545 /* 546 * If this architecture has a "base" platform capability 547 * string, copy it to userspace. 548 */ 549 k_base_platform = ELF_BASE_PLATFORM; 550 u_base_platform = NULL; 551 552 if (k_base_platform) { 553 platform_len = strlen(k_base_platform) + 1; 554 sp -= platform_len; 555 u_base_platform = (char __user *) sp; 556 if (copy_to_user(u_base_platform, k_base_platform, platform_len) != 0) 557 return -EFAULT; 558 } 559 560 sp &= ~7UL; 561 562 /* stack the load map(s) */ 563 len = sizeof(struct elf32_fdpic_loadmap); 564 len += sizeof(struct elf32_fdpic_loadseg) * exec_params->loadmap->nsegs; 565 sp = (sp - len) & ~7UL; 566 exec_params->map_addr = sp; 567 568 if (copy_to_user((void __user *) sp, exec_params->loadmap, len) != 0) 569 return -EFAULT; 570 571 current->mm->context.exec_fdpic_loadmap = (unsigned long) sp; 572 573 if (interp_params->loadmap) { 574 len = sizeof(struct elf32_fdpic_loadmap); 575 len += sizeof(struct elf32_fdpic_loadseg) * 576 interp_params->loadmap->nsegs; 577 sp = (sp - len) & ~7UL; 578 interp_params->map_addr = sp; 579 580 if (copy_to_user((void __user *) sp, interp_params->loadmap, 581 len) != 0) 582 return -EFAULT; 583 584 current->mm->context.interp_fdpic_loadmap = (unsigned long) sp; 585 } 586 587 /* force 16 byte _final_ alignment here for generality */ 588 #define DLINFO_ITEMS 15 589 590 nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) + 591 (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH; 592 593 if (bprm->have_execfd) 594 nitems++; 595 596 csp = sp; 597 sp -= nitems * 2 * sizeof(unsigned long); 598 sp -= (bprm->envc + 1) * sizeof(char *); /* envv[] */ 599 sp -= (bprm->argc + 1) * sizeof(char *); /* argv[] */ 600 sp -= 1 * sizeof(unsigned long); /* argc */ 601 602 csp -= sp & 15UL; 603 sp -= sp & 15UL; 604 605 /* put the ELF interpreter info on the stack */ 606 #define NEW_AUX_ENT(id, val) \ 607 do { \ 608 struct { unsigned long _id, _val; } __user *ent, v; \ 609 \ 610 ent = (void __user *) csp; \ 611 v._id = (id); \ 612 v._val = (val); \ 613 if (copy_to_user(ent + nr, &v, sizeof(v))) \ 614 return -EFAULT; \ 615 nr++; \ 616 } while (0) 617 618 nr = 0; 619 csp -= 2 * sizeof(unsigned long); 620 NEW_AUX_ENT(AT_NULL, 0); 621 if (k_platform) { 622 nr = 0; 623 csp -= 2 * sizeof(unsigned long); 624 NEW_AUX_ENT(AT_PLATFORM, 625 (elf_addr_t) (unsigned long) u_platform); 626 } 627 628 if (k_base_platform) { 629 nr = 0; 630 csp -= 2 * sizeof(unsigned long); 631 NEW_AUX_ENT(AT_BASE_PLATFORM, 632 (elf_addr_t) (unsigned long) u_base_platform); 633 } 634 635 if (bprm->have_execfd) { 636 nr = 0; 637 csp -= 2 * sizeof(unsigned long); 638 NEW_AUX_ENT(AT_EXECFD, bprm->execfd); 639 } 640 641 nr = 0; 642 csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long); 643 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP); 644 #ifdef ELF_HWCAP2 645 NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2); 646 #endif 647 NEW_AUX_ENT(AT_PAGESZ, PAGE_SIZE); 648 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC); 649 NEW_AUX_ENT(AT_PHDR, exec_params->ph_addr); 650 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); 651 NEW_AUX_ENT(AT_PHNUM, exec_params->hdr.e_phnum); 652 NEW_AUX_ENT(AT_BASE, interp_params->elfhdr_addr); 653 if (bprm->interp_flags & BINPRM_FLAGS_PRESERVE_ARGV0) 654 flags |= AT_FLAGS_PRESERVE_ARGV0; 655 NEW_AUX_ENT(AT_FLAGS, flags); 656 NEW_AUX_ENT(AT_ENTRY, exec_params->entry_addr); 657 NEW_AUX_ENT(AT_UID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->uid)); 658 NEW_AUX_ENT(AT_EUID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->euid)); 659 NEW_AUX_ENT(AT_GID, (elf_addr_t) from_kgid_munged(cred->user_ns, cred->gid)); 660 NEW_AUX_ENT(AT_EGID, (elf_addr_t) from_kgid_munged(cred->user_ns, cred->egid)); 661 NEW_AUX_ENT(AT_SECURE, bprm->secureexec); 662 NEW_AUX_ENT(AT_EXECFN, bprm->exec); 663 664 #ifdef ARCH_DLINFO 665 nr = 0; 666 csp -= AT_VECTOR_SIZE_ARCH * 2 * sizeof(unsigned long); 667 668 /* ARCH_DLINFO must come last so platform specific code can enforce 669 * special alignment requirements on the AUXV if necessary (eg. PPC). 670 */ 671 ARCH_DLINFO; 672 #endif 673 #undef NEW_AUX_ENT 674 675 /* allocate room for argv[] and envv[] */ 676 csp -= (bprm->envc + 1) * sizeof(elf_caddr_t); 677 envp = (elf_caddr_t __user *) csp; 678 csp -= (bprm->argc + 1) * sizeof(elf_caddr_t); 679 argv = (elf_caddr_t __user *) csp; 680 681 /* stack argc */ 682 csp -= sizeof(unsigned long); 683 if (put_user(bprm->argc, (unsigned long __user *) csp)) 684 return -EFAULT; 685 686 BUG_ON(csp != sp); 687 688 /* fill in the argv[] array */ 689 #ifdef CONFIG_MMU 690 current->mm->arg_start = bprm->p; 691 #else 692 current->mm->arg_start = current->mm->start_stack - 693 (MAX_ARG_PAGES * PAGE_SIZE - bprm->p); 694 #endif 695 696 p = (char __user *) current->mm->arg_start; 697 for (loop = bprm->argc; loop > 0; loop--) { 698 if (put_user((elf_caddr_t) p, argv++)) 699 return -EFAULT; 700 len = strnlen_user(p, MAX_ARG_STRLEN); 701 if (!len || len > MAX_ARG_STRLEN) 702 return -EINVAL; 703 p += len; 704 } 705 if (put_user(NULL, argv)) 706 return -EFAULT; 707 current->mm->arg_end = (unsigned long) p; 708 709 /* fill in the envv[] array */ 710 current->mm->env_start = (unsigned long) p; 711 for (loop = bprm->envc; loop > 0; loop--) { 712 if (put_user((elf_caddr_t)(unsigned long) p, envp++)) 713 return -EFAULT; 714 len = strnlen_user(p, MAX_ARG_STRLEN); 715 if (!len || len > MAX_ARG_STRLEN) 716 return -EINVAL; 717 p += len; 718 } 719 if (put_user(NULL, envp)) 720 return -EFAULT; 721 current->mm->env_end = (unsigned long) p; 722 723 mm->start_stack = (unsigned long) sp; 724 return 0; 725 } 726 727 /*****************************************************************************/ 728 /* 729 * load the appropriate binary image (executable or interpreter) into memory 730 * - we assume no MMU is available 731 * - if no other PIC bits are set in params->hdr->e_flags 732 * - we assume that the LOADable segments in the binary are independently relocatable 733 * - we assume R/O executable segments are shareable 734 * - else 735 * - we assume the loadable parts of the image to require fixed displacement 736 * - the image is not shareable 737 */ 738 static int elf_fdpic_map_file(struct elf_fdpic_params *params, 739 struct file *file, 740 struct mm_struct *mm, 741 const char *what) 742 { 743 struct elf32_fdpic_loadmap *loadmap; 744 #ifdef CONFIG_MMU 745 struct elf32_fdpic_loadseg *mseg; 746 #endif 747 struct elf32_fdpic_loadseg *seg; 748 struct elf32_phdr *phdr; 749 unsigned long load_addr, stop; 750 unsigned nloads, tmp; 751 size_t size; 752 int loop, ret; 753 754 /* allocate a load map table */ 755 nloads = 0; 756 for (loop = 0; loop < params->hdr.e_phnum; loop++) 757 if (params->phdrs[loop].p_type == PT_LOAD) 758 nloads++; 759 760 if (nloads == 0) 761 return -ELIBBAD; 762 763 size = sizeof(*loadmap) + nloads * sizeof(*seg); 764 loadmap = kzalloc(size, GFP_KERNEL); 765 if (!loadmap) 766 return -ENOMEM; 767 768 params->loadmap = loadmap; 769 770 loadmap->version = ELF32_FDPIC_LOADMAP_VERSION; 771 loadmap->nsegs = nloads; 772 773 load_addr = params->load_addr; 774 seg = loadmap->segs; 775 776 /* map the requested LOADs into the memory space */ 777 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) { 778 case ELF_FDPIC_FLAG_CONSTDISP: 779 case ELF_FDPIC_FLAG_CONTIGUOUS: 780 #ifndef CONFIG_MMU 781 ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm); 782 if (ret < 0) 783 return ret; 784 break; 785 #endif 786 default: 787 ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm); 788 if (ret < 0) 789 return ret; 790 break; 791 } 792 793 /* map the entry point */ 794 if (params->hdr.e_entry) { 795 seg = loadmap->segs; 796 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) { 797 if (params->hdr.e_entry >= seg->p_vaddr && 798 params->hdr.e_entry < seg->p_vaddr + seg->p_memsz) { 799 params->entry_addr = 800 (params->hdr.e_entry - seg->p_vaddr) + 801 seg->addr; 802 break; 803 } 804 } 805 } 806 807 /* determine where the program header table has wound up if mapped */ 808 stop = params->hdr.e_phoff; 809 stop += params->hdr.e_phnum * sizeof (struct elf_phdr); 810 phdr = params->phdrs; 811 812 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 813 if (phdr->p_type != PT_LOAD) 814 continue; 815 816 if (phdr->p_offset > params->hdr.e_phoff || 817 phdr->p_offset + phdr->p_filesz < stop) 818 continue; 819 820 seg = loadmap->segs; 821 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) { 822 if (phdr->p_vaddr >= seg->p_vaddr && 823 phdr->p_vaddr + phdr->p_filesz <= 824 seg->p_vaddr + seg->p_memsz) { 825 params->ph_addr = 826 (phdr->p_vaddr - seg->p_vaddr) + 827 seg->addr + 828 params->hdr.e_phoff - phdr->p_offset; 829 break; 830 } 831 } 832 break; 833 } 834 835 /* determine where the dynamic section has wound up if there is one */ 836 phdr = params->phdrs; 837 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 838 if (phdr->p_type != PT_DYNAMIC) 839 continue; 840 841 seg = loadmap->segs; 842 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) { 843 if (phdr->p_vaddr >= seg->p_vaddr && 844 phdr->p_vaddr + phdr->p_memsz <= 845 seg->p_vaddr + seg->p_memsz) { 846 Elf32_Dyn __user *dyn; 847 Elf32_Sword d_tag; 848 849 params->dynamic_addr = 850 (phdr->p_vaddr - seg->p_vaddr) + 851 seg->addr; 852 853 /* check the dynamic section contains at least 854 * one item, and that the last item is a NULL 855 * entry */ 856 if (phdr->p_memsz == 0 || 857 phdr->p_memsz % sizeof(Elf32_Dyn) != 0) 858 goto dynamic_error; 859 860 tmp = phdr->p_memsz / sizeof(Elf32_Dyn); 861 dyn = (Elf32_Dyn __user *)params->dynamic_addr; 862 if (get_user(d_tag, &dyn[tmp - 1].d_tag) || 863 d_tag != 0) 864 goto dynamic_error; 865 break; 866 } 867 } 868 break; 869 } 870 871 /* now elide adjacent segments in the load map on MMU linux 872 * - on uClinux the holes between may actually be filled with system 873 * stuff or stuff from other processes 874 */ 875 #ifdef CONFIG_MMU 876 nloads = loadmap->nsegs; 877 mseg = loadmap->segs; 878 seg = mseg + 1; 879 for (loop = 1; loop < nloads; loop++) { 880 /* see if we have a candidate for merging */ 881 if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) { 882 load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz); 883 if (load_addr == (seg->addr & PAGE_MASK)) { 884 mseg->p_memsz += 885 load_addr - 886 (mseg->addr + mseg->p_memsz); 887 mseg->p_memsz += seg->addr & ~PAGE_MASK; 888 mseg->p_memsz += seg->p_memsz; 889 loadmap->nsegs--; 890 continue; 891 } 892 } 893 894 mseg++; 895 if (mseg != seg) 896 *mseg = *seg; 897 } 898 #endif 899 900 kdebug("Mapped Object [%s]:", what); 901 kdebug("- elfhdr : %lx", params->elfhdr_addr); 902 kdebug("- entry : %lx", params->entry_addr); 903 kdebug("- PHDR[] : %lx", params->ph_addr); 904 kdebug("- DYNAMIC[]: %lx", params->dynamic_addr); 905 seg = loadmap->segs; 906 for (loop = 0; loop < loadmap->nsegs; loop++, seg++) 907 kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]", 908 loop, 909 seg->addr, seg->addr + seg->p_memsz - 1, 910 seg->p_vaddr, seg->p_memsz); 911 912 return 0; 913 914 dynamic_error: 915 printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n", 916 what, file_inode(file)->i_ino); 917 return -ELIBBAD; 918 } 919 920 /*****************************************************************************/ 921 /* 922 * map a file with constant displacement under uClinux 923 */ 924 #ifndef CONFIG_MMU 925 static int elf_fdpic_map_file_constdisp_on_uclinux( 926 struct elf_fdpic_params *params, 927 struct file *file, 928 struct mm_struct *mm) 929 { 930 struct elf32_fdpic_loadseg *seg; 931 struct elf32_phdr *phdr; 932 unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0; 933 int loop, ret; 934 935 load_addr = params->load_addr; 936 seg = params->loadmap->segs; 937 938 /* determine the bounds of the contiguous overall allocation we must 939 * make */ 940 phdr = params->phdrs; 941 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 942 if (params->phdrs[loop].p_type != PT_LOAD) 943 continue; 944 945 if (base > phdr->p_vaddr) 946 base = phdr->p_vaddr; 947 if (top < phdr->p_vaddr + phdr->p_memsz) 948 top = phdr->p_vaddr + phdr->p_memsz; 949 } 950 951 /* allocate one big anon block for everything */ 952 maddr = vm_mmap(NULL, load_addr, top - base, 953 PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE, 0); 954 if (IS_ERR_VALUE(maddr)) 955 return (int) maddr; 956 957 if (load_addr != 0) 958 load_addr += PAGE_ALIGN(top - base); 959 960 /* and then load the file segments into it */ 961 phdr = params->phdrs; 962 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 963 if (params->phdrs[loop].p_type != PT_LOAD) 964 continue; 965 966 seg->addr = maddr + (phdr->p_vaddr - base); 967 seg->p_vaddr = phdr->p_vaddr; 968 seg->p_memsz = phdr->p_memsz; 969 970 ret = read_code(file, seg->addr, phdr->p_offset, 971 phdr->p_filesz); 972 if (ret < 0) 973 return ret; 974 975 /* map the ELF header address if in this segment */ 976 if (phdr->p_offset == 0) 977 params->elfhdr_addr = seg->addr; 978 979 /* clear any space allocated but not loaded */ 980 if (phdr->p_filesz < phdr->p_memsz) { 981 if (clear_user((void *) (seg->addr + phdr->p_filesz), 982 phdr->p_memsz - phdr->p_filesz)) 983 return -EFAULT; 984 } 985 986 if (mm) { 987 if (phdr->p_flags & PF_X) { 988 if (!mm->start_code) { 989 mm->start_code = seg->addr; 990 mm->end_code = seg->addr + 991 phdr->p_memsz; 992 } 993 } else if (!mm->start_data) { 994 mm->start_data = seg->addr; 995 mm->end_data = seg->addr + phdr->p_memsz; 996 } 997 } 998 999 seg++; 1000 } 1001 1002 return 0; 1003 } 1004 #endif 1005 1006 /*****************************************************************************/ 1007 /* 1008 * map a binary by direct mmap() of the individual PT_LOAD segments 1009 */ 1010 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params, 1011 struct file *file, 1012 struct mm_struct *mm) 1013 { 1014 struct elf32_fdpic_loadseg *seg; 1015 struct elf32_phdr *phdr; 1016 unsigned long load_addr, delta_vaddr; 1017 int loop, dvset; 1018 1019 load_addr = params->load_addr; 1020 delta_vaddr = 0; 1021 dvset = 0; 1022 1023 seg = params->loadmap->segs; 1024 1025 /* deal with each load segment separately */ 1026 phdr = params->phdrs; 1027 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 1028 unsigned long maddr, disp, excess, excess1; 1029 int prot = 0, flags; 1030 1031 if (phdr->p_type != PT_LOAD) 1032 continue; 1033 1034 kdebug("[LOAD] va=%lx of=%lx fs=%lx ms=%lx", 1035 (unsigned long) phdr->p_vaddr, 1036 (unsigned long) phdr->p_offset, 1037 (unsigned long) phdr->p_filesz, 1038 (unsigned long) phdr->p_memsz); 1039 1040 /* determine the mapping parameters */ 1041 if (phdr->p_flags & PF_R) prot |= PROT_READ; 1042 if (phdr->p_flags & PF_W) prot |= PROT_WRITE; 1043 if (phdr->p_flags & PF_X) prot |= PROT_EXEC; 1044 1045 flags = MAP_PRIVATE; 1046 maddr = 0; 1047 1048 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) { 1049 case ELF_FDPIC_FLAG_INDEPENDENT: 1050 /* PT_LOADs are independently locatable */ 1051 break; 1052 1053 case ELF_FDPIC_FLAG_HONOURVADDR: 1054 /* the specified virtual address must be honoured */ 1055 maddr = phdr->p_vaddr; 1056 flags |= MAP_FIXED; 1057 break; 1058 1059 case ELF_FDPIC_FLAG_CONSTDISP: 1060 /* constant displacement 1061 * - can be mapped anywhere, but must be mapped as a 1062 * unit 1063 */ 1064 if (!dvset) { 1065 maddr = load_addr; 1066 delta_vaddr = phdr->p_vaddr; 1067 dvset = 1; 1068 } else { 1069 maddr = load_addr + phdr->p_vaddr - delta_vaddr; 1070 flags |= MAP_FIXED; 1071 } 1072 break; 1073 1074 case ELF_FDPIC_FLAG_CONTIGUOUS: 1075 /* contiguity handled later */ 1076 break; 1077 1078 default: 1079 BUG(); 1080 } 1081 1082 maddr &= PAGE_MASK; 1083 1084 /* create the mapping */ 1085 disp = phdr->p_vaddr & ~PAGE_MASK; 1086 maddr = vm_mmap(file, maddr, phdr->p_memsz + disp, prot, flags, 1087 phdr->p_offset - disp); 1088 1089 kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx", 1090 loop, phdr->p_memsz + disp, prot, flags, 1091 phdr->p_offset - disp, maddr); 1092 1093 if (IS_ERR_VALUE(maddr)) 1094 return (int) maddr; 1095 1096 if ((params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) == 1097 ELF_FDPIC_FLAG_CONTIGUOUS) 1098 load_addr += PAGE_ALIGN(phdr->p_memsz + disp); 1099 1100 seg->addr = maddr + disp; 1101 seg->p_vaddr = phdr->p_vaddr; 1102 seg->p_memsz = phdr->p_memsz; 1103 1104 /* map the ELF header address if in this segment */ 1105 if (phdr->p_offset == 0) 1106 params->elfhdr_addr = seg->addr; 1107 1108 /* clear the bit between beginning of mapping and beginning of 1109 * PT_LOAD */ 1110 if (prot & PROT_WRITE && disp > 0) { 1111 kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp); 1112 if (clear_user((void __user *) maddr, disp)) 1113 return -EFAULT; 1114 maddr += disp; 1115 } 1116 1117 /* clear any space allocated but not loaded 1118 * - on uClinux we can just clear the lot 1119 * - on MMU linux we'll get a SIGBUS beyond the last page 1120 * extant in the file 1121 */ 1122 excess = phdr->p_memsz - phdr->p_filesz; 1123 excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK); 1124 1125 #ifdef CONFIG_MMU 1126 if (excess > excess1) { 1127 unsigned long xaddr = maddr + phdr->p_filesz + excess1; 1128 unsigned long xmaddr; 1129 1130 flags |= MAP_FIXED | MAP_ANONYMOUS; 1131 xmaddr = vm_mmap(NULL, xaddr, excess - excess1, 1132 prot, flags, 0); 1133 1134 kdebug("mmap[%d] <anon>" 1135 " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx", 1136 loop, xaddr, excess - excess1, prot, flags, 1137 xmaddr); 1138 1139 if (xmaddr != xaddr) 1140 return -ENOMEM; 1141 } 1142 1143 if (prot & PROT_WRITE && excess1 > 0) { 1144 kdebug("clear[%d] ad=%lx sz=%lx", 1145 loop, maddr + phdr->p_filesz, excess1); 1146 if (clear_user((void __user *) maddr + phdr->p_filesz, 1147 excess1)) 1148 return -EFAULT; 1149 } 1150 1151 #else 1152 if (excess > 0) { 1153 kdebug("clear[%d] ad=%lx sz=%lx", 1154 loop, maddr + phdr->p_filesz, excess); 1155 if (clear_user((void *) maddr + phdr->p_filesz, excess)) 1156 return -EFAULT; 1157 } 1158 #endif 1159 1160 if (mm) { 1161 if (phdr->p_flags & PF_X) { 1162 if (!mm->start_code) { 1163 mm->start_code = maddr; 1164 mm->end_code = maddr + phdr->p_memsz; 1165 } 1166 } else if (!mm->start_data) { 1167 mm->start_data = maddr; 1168 mm->end_data = maddr + phdr->p_memsz; 1169 } 1170 } 1171 1172 seg++; 1173 } 1174 1175 return 0; 1176 } 1177 1178 /*****************************************************************************/ 1179 /* 1180 * ELF-FDPIC core dumper 1181 * 1182 * Modelled on fs/exec.c:aout_core_dump() 1183 * Jeremy Fitzhardinge <jeremy@sw.oz.au> 1184 * 1185 * Modelled on fs/binfmt_elf.c core dumper 1186 */ 1187 #ifdef CONFIG_ELF_CORE 1188 1189 struct elf_prstatus_fdpic 1190 { 1191 struct elf_prstatus_common common; 1192 elf_gregset_t pr_reg; /* GP registers */ 1193 /* When using FDPIC, the loadmap addresses need to be communicated 1194 * to GDB in order for GDB to do the necessary relocations. The 1195 * fields (below) used to communicate this information are placed 1196 * immediately after ``pr_reg'', so that the loadmap addresses may 1197 * be viewed as part of the register set if so desired. 1198 */ 1199 unsigned long pr_exec_fdpic_loadmap; 1200 unsigned long pr_interp_fdpic_loadmap; 1201 int pr_fpvalid; /* True if math co-processor being used. */ 1202 }; 1203 1204 /* An ELF note in memory */ 1205 struct memelfnote 1206 { 1207 const char *name; 1208 int type; 1209 unsigned int datasz; 1210 void *data; 1211 }; 1212 1213 static int notesize(struct memelfnote *en) 1214 { 1215 int sz; 1216 1217 sz = sizeof(struct elf_note); 1218 sz += roundup(strlen(en->name) + 1, 4); 1219 sz += roundup(en->datasz, 4); 1220 1221 return sz; 1222 } 1223 1224 /* #define DEBUG */ 1225 1226 static int writenote(struct memelfnote *men, struct coredump_params *cprm) 1227 { 1228 struct elf_note en; 1229 en.n_namesz = strlen(men->name) + 1; 1230 en.n_descsz = men->datasz; 1231 en.n_type = men->type; 1232 1233 return dump_emit(cprm, &en, sizeof(en)) && 1234 dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) && 1235 dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4); 1236 } 1237 1238 static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs) 1239 { 1240 memcpy(elf->e_ident, ELFMAG, SELFMAG); 1241 elf->e_ident[EI_CLASS] = ELF_CLASS; 1242 elf->e_ident[EI_DATA] = ELF_DATA; 1243 elf->e_ident[EI_VERSION] = EV_CURRENT; 1244 elf->e_ident[EI_OSABI] = ELF_OSABI; 1245 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); 1246 1247 elf->e_type = ET_CORE; 1248 elf->e_machine = ELF_ARCH; 1249 elf->e_version = EV_CURRENT; 1250 elf->e_entry = 0; 1251 elf->e_phoff = sizeof(struct elfhdr); 1252 elf->e_shoff = 0; 1253 elf->e_flags = ELF_FDPIC_CORE_EFLAGS; 1254 elf->e_ehsize = sizeof(struct elfhdr); 1255 elf->e_phentsize = sizeof(struct elf_phdr); 1256 elf->e_phnum = segs; 1257 elf->e_shentsize = 0; 1258 elf->e_shnum = 0; 1259 elf->e_shstrndx = 0; 1260 return; 1261 } 1262 1263 static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset) 1264 { 1265 phdr->p_type = PT_NOTE; 1266 phdr->p_offset = offset; 1267 phdr->p_vaddr = 0; 1268 phdr->p_paddr = 0; 1269 phdr->p_filesz = sz; 1270 phdr->p_memsz = 0; 1271 phdr->p_flags = 0; 1272 phdr->p_align = 0; 1273 return; 1274 } 1275 1276 static inline void fill_note(struct memelfnote *note, const char *name, int type, 1277 unsigned int sz, void *data) 1278 { 1279 note->name = name; 1280 note->type = type; 1281 note->datasz = sz; 1282 note->data = data; 1283 return; 1284 } 1285 1286 /* 1287 * fill up all the fields in prstatus from the given task struct, except 1288 * registers which need to be filled up separately. 1289 */ 1290 static void fill_prstatus(struct elf_prstatus_common *prstatus, 1291 struct task_struct *p, long signr) 1292 { 1293 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr; 1294 prstatus->pr_sigpend = p->pending.signal.sig[0]; 1295 prstatus->pr_sighold = p->blocked.sig[0]; 1296 rcu_read_lock(); 1297 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); 1298 rcu_read_unlock(); 1299 prstatus->pr_pid = task_pid_vnr(p); 1300 prstatus->pr_pgrp = task_pgrp_vnr(p); 1301 prstatus->pr_sid = task_session_vnr(p); 1302 if (thread_group_leader(p)) { 1303 struct task_cputime cputime; 1304 1305 /* 1306 * This is the record for the group leader. It shows the 1307 * group-wide total, not its individual thread total. 1308 */ 1309 thread_group_cputime(p, &cputime); 1310 prstatus->pr_utime = ns_to_kernel_old_timeval(cputime.utime); 1311 prstatus->pr_stime = ns_to_kernel_old_timeval(cputime.stime); 1312 } else { 1313 u64 utime, stime; 1314 1315 task_cputime(p, &utime, &stime); 1316 prstatus->pr_utime = ns_to_kernel_old_timeval(utime); 1317 prstatus->pr_stime = ns_to_kernel_old_timeval(stime); 1318 } 1319 prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime); 1320 prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime); 1321 } 1322 1323 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, 1324 struct mm_struct *mm) 1325 { 1326 const struct cred *cred; 1327 unsigned int i, len; 1328 unsigned int state; 1329 1330 /* first copy the parameters from user space */ 1331 memset(psinfo, 0, sizeof(struct elf_prpsinfo)); 1332 1333 len = mm->arg_end - mm->arg_start; 1334 if (len >= ELF_PRARGSZ) 1335 len = ELF_PRARGSZ - 1; 1336 if (copy_from_user(&psinfo->pr_psargs, 1337 (const char __user *) mm->arg_start, len)) 1338 return -EFAULT; 1339 for (i = 0; i < len; i++) 1340 if (psinfo->pr_psargs[i] == 0) 1341 psinfo->pr_psargs[i] = ' '; 1342 psinfo->pr_psargs[len] = 0; 1343 1344 rcu_read_lock(); 1345 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); 1346 rcu_read_unlock(); 1347 psinfo->pr_pid = task_pid_vnr(p); 1348 psinfo->pr_pgrp = task_pgrp_vnr(p); 1349 psinfo->pr_sid = task_session_vnr(p); 1350 1351 state = READ_ONCE(p->__state); 1352 i = state ? ffz(~state) + 1 : 0; 1353 psinfo->pr_state = i; 1354 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i]; 1355 psinfo->pr_zomb = psinfo->pr_sname == 'Z'; 1356 psinfo->pr_nice = task_nice(p); 1357 psinfo->pr_flag = p->flags; 1358 rcu_read_lock(); 1359 cred = __task_cred(p); 1360 SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid)); 1361 SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid)); 1362 rcu_read_unlock(); 1363 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); 1364 1365 return 0; 1366 } 1367 1368 /* Here is the structure in which status of each thread is captured. */ 1369 struct elf_thread_status 1370 { 1371 struct elf_thread_status *next; 1372 struct elf_prstatus_fdpic prstatus; /* NT_PRSTATUS */ 1373 elf_fpregset_t fpu; /* NT_PRFPREG */ 1374 struct memelfnote notes[2]; 1375 int num_notes; 1376 }; 1377 1378 /* 1379 * In order to add the specific thread information for the elf file format, 1380 * we need to keep a linked list of every thread's pr_status and then create 1381 * a single section for them in the final core file. 1382 */ 1383 static struct elf_thread_status *elf_dump_thread_status(long signr, struct task_struct *p, int *sz) 1384 { 1385 const struct user_regset_view *view = task_user_regset_view(p); 1386 struct elf_thread_status *t; 1387 int i, ret; 1388 1389 t = kzalloc(sizeof(struct elf_thread_status), GFP_KERNEL); 1390 if (!t) 1391 return t; 1392 1393 fill_prstatus(&t->prstatus.common, p, signr); 1394 t->prstatus.pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap; 1395 t->prstatus.pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap; 1396 regset_get(p, &view->regsets[0], 1397 sizeof(t->prstatus.pr_reg), &t->prstatus.pr_reg); 1398 1399 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), 1400 &t->prstatus); 1401 t->num_notes++; 1402 *sz += notesize(&t->notes[0]); 1403 1404 for (i = 1; i < view->n; ++i) { 1405 const struct user_regset *regset = &view->regsets[i]; 1406 if (regset->core_note_type != NT_PRFPREG) 1407 continue; 1408 if (regset->active && regset->active(p, regset) <= 0) 1409 continue; 1410 ret = regset_get(p, regset, sizeof(t->fpu), &t->fpu); 1411 if (ret >= 0) 1412 t->prstatus.pr_fpvalid = 1; 1413 break; 1414 } 1415 1416 if (t->prstatus.pr_fpvalid) { 1417 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), 1418 &t->fpu); 1419 t->num_notes++; 1420 *sz += notesize(&t->notes[1]); 1421 } 1422 return t; 1423 } 1424 1425 static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum, 1426 elf_addr_t e_shoff, int segs) 1427 { 1428 elf->e_shoff = e_shoff; 1429 elf->e_shentsize = sizeof(*shdr4extnum); 1430 elf->e_shnum = 1; 1431 elf->e_shstrndx = SHN_UNDEF; 1432 1433 memset(shdr4extnum, 0, sizeof(*shdr4extnum)); 1434 1435 shdr4extnum->sh_type = SHT_NULL; 1436 shdr4extnum->sh_size = elf->e_shnum; 1437 shdr4extnum->sh_link = elf->e_shstrndx; 1438 shdr4extnum->sh_info = segs; 1439 } 1440 1441 /* 1442 * dump the segments for an MMU process 1443 */ 1444 static bool elf_fdpic_dump_segments(struct coredump_params *cprm, 1445 struct core_vma_metadata *vma_meta, 1446 int vma_count) 1447 { 1448 int i; 1449 1450 for (i = 0; i < vma_count; i++) { 1451 struct core_vma_metadata *meta = vma_meta + i; 1452 1453 if (!dump_user_range(cprm, meta->start, meta->dump_size)) 1454 return false; 1455 } 1456 return true; 1457 } 1458 1459 /* 1460 * Actual dumper 1461 * 1462 * This is a two-pass process; first we find the offsets of the bits, 1463 * and then they are actually written out. If we run out of core limit 1464 * we just truncate. 1465 */ 1466 static int elf_fdpic_core_dump(struct coredump_params *cprm) 1467 { 1468 int has_dumped = 0; 1469 int segs; 1470 int i; 1471 struct elfhdr *elf = NULL; 1472 loff_t offset = 0, dataoff; 1473 struct memelfnote psinfo_note, auxv_note; 1474 struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */ 1475 struct elf_thread_status *thread_list = NULL; 1476 int thread_status_size = 0; 1477 elf_addr_t *auxv; 1478 struct elf_phdr *phdr4note = NULL; 1479 struct elf_shdr *shdr4extnum = NULL; 1480 Elf_Half e_phnum; 1481 elf_addr_t e_shoff; 1482 struct core_thread *ct; 1483 struct elf_thread_status *tmp; 1484 1485 /* alloc memory for large data structures: too large to be on stack */ 1486 elf = kmalloc(sizeof(*elf), GFP_KERNEL); 1487 if (!elf) 1488 goto end_coredump; 1489 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL); 1490 if (!psinfo) 1491 goto end_coredump; 1492 1493 for (ct = current->signal->core_state->dumper.next; 1494 ct; ct = ct->next) { 1495 tmp = elf_dump_thread_status(cprm->siginfo->si_signo, 1496 ct->task, &thread_status_size); 1497 if (!tmp) 1498 goto end_coredump; 1499 1500 tmp->next = thread_list; 1501 thread_list = tmp; 1502 } 1503 1504 /* now collect the dump for the current */ 1505 tmp = elf_dump_thread_status(cprm->siginfo->si_signo, 1506 current, &thread_status_size); 1507 if (!tmp) 1508 goto end_coredump; 1509 tmp->next = thread_list; 1510 thread_list = tmp; 1511 1512 segs = cprm->vma_count + elf_core_extra_phdrs(cprm); 1513 1514 /* for notes section */ 1515 segs++; 1516 1517 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid 1518 * this, kernel supports extended numbering. Have a look at 1519 * include/linux/elf.h for further information. */ 1520 e_phnum = segs > PN_XNUM ? PN_XNUM : segs; 1521 1522 /* Set up header */ 1523 fill_elf_fdpic_header(elf, e_phnum); 1524 1525 has_dumped = 1; 1526 /* 1527 * Set up the notes in similar form to SVR4 core dumps made 1528 * with info from their /proc. 1529 */ 1530 1531 fill_psinfo(psinfo, current->group_leader, current->mm); 1532 fill_note(&psinfo_note, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo); 1533 thread_status_size += notesize(&psinfo_note); 1534 1535 auxv = (elf_addr_t *) current->mm->saved_auxv; 1536 i = 0; 1537 do 1538 i += 2; 1539 while (auxv[i - 2] != AT_NULL); 1540 fill_note(&auxv_note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv); 1541 thread_status_size += notesize(&auxv_note); 1542 1543 offset = sizeof(*elf); /* Elf header */ 1544 offset += segs * sizeof(struct elf_phdr); /* Program headers */ 1545 1546 /* Write notes phdr entry */ 1547 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL); 1548 if (!phdr4note) 1549 goto end_coredump; 1550 1551 fill_elf_note_phdr(phdr4note, thread_status_size, offset); 1552 offset += thread_status_size; 1553 1554 /* Page-align dumped data */ 1555 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); 1556 1557 offset += cprm->vma_data_size; 1558 offset += elf_core_extra_data_size(cprm); 1559 e_shoff = offset; 1560 1561 if (e_phnum == PN_XNUM) { 1562 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL); 1563 if (!shdr4extnum) 1564 goto end_coredump; 1565 fill_extnum_info(elf, shdr4extnum, e_shoff, segs); 1566 } 1567 1568 offset = dataoff; 1569 1570 if (!dump_emit(cprm, elf, sizeof(*elf))) 1571 goto end_coredump; 1572 1573 if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note))) 1574 goto end_coredump; 1575 1576 /* write program headers for segments dump */ 1577 for (i = 0; i < cprm->vma_count; i++) { 1578 struct core_vma_metadata *meta = cprm->vma_meta + i; 1579 struct elf_phdr phdr; 1580 size_t sz; 1581 1582 sz = meta->end - meta->start; 1583 1584 phdr.p_type = PT_LOAD; 1585 phdr.p_offset = offset; 1586 phdr.p_vaddr = meta->start; 1587 phdr.p_paddr = 0; 1588 phdr.p_filesz = meta->dump_size; 1589 phdr.p_memsz = sz; 1590 offset += phdr.p_filesz; 1591 phdr.p_flags = 0; 1592 if (meta->flags & VM_READ) 1593 phdr.p_flags |= PF_R; 1594 if (meta->flags & VM_WRITE) 1595 phdr.p_flags |= PF_W; 1596 if (meta->flags & VM_EXEC) 1597 phdr.p_flags |= PF_X; 1598 phdr.p_align = ELF_EXEC_PAGESIZE; 1599 1600 if (!dump_emit(cprm, &phdr, sizeof(phdr))) 1601 goto end_coredump; 1602 } 1603 1604 if (!elf_core_write_extra_phdrs(cprm, offset)) 1605 goto end_coredump; 1606 1607 /* write out the notes section */ 1608 if (!writenote(thread_list->notes, cprm)) 1609 goto end_coredump; 1610 if (!writenote(&psinfo_note, cprm)) 1611 goto end_coredump; 1612 if (!writenote(&auxv_note, cprm)) 1613 goto end_coredump; 1614 for (i = 1; i < thread_list->num_notes; i++) 1615 if (!writenote(thread_list->notes + i, cprm)) 1616 goto end_coredump; 1617 1618 /* write out the thread status notes section */ 1619 for (tmp = thread_list->next; tmp; tmp = tmp->next) { 1620 for (i = 0; i < tmp->num_notes; i++) 1621 if (!writenote(&tmp->notes[i], cprm)) 1622 goto end_coredump; 1623 } 1624 1625 dump_skip_to(cprm, dataoff); 1626 1627 if (!elf_fdpic_dump_segments(cprm, cprm->vma_meta, cprm->vma_count)) 1628 goto end_coredump; 1629 1630 if (!elf_core_write_extra_data(cprm)) 1631 goto end_coredump; 1632 1633 if (e_phnum == PN_XNUM) { 1634 if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum))) 1635 goto end_coredump; 1636 } 1637 1638 if (cprm->file->f_pos != offset) { 1639 /* Sanity check */ 1640 printk(KERN_WARNING 1641 "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n", 1642 cprm->file->f_pos, offset); 1643 } 1644 1645 end_coredump: 1646 while (thread_list) { 1647 tmp = thread_list; 1648 thread_list = thread_list->next; 1649 kfree(tmp); 1650 } 1651 kfree(phdr4note); 1652 kfree(elf); 1653 kfree(psinfo); 1654 kfree(shdr4extnum); 1655 return has_dumped; 1656 } 1657 1658 #endif /* CONFIG_ELF_CORE */ 1659