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 #endif 87 .min_coredump = ELF_EXEC_PAGESIZE, 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 if (create_elf_fdpic_tables(bprm, current->mm, 438 &exec_params, &interp_params) < 0) 439 goto error; 440 441 kdebug("- start_code %lx", current->mm->start_code); 442 kdebug("- end_code %lx", current->mm->end_code); 443 kdebug("- start_data %lx", current->mm->start_data); 444 kdebug("- end_data %lx", current->mm->end_data); 445 kdebug("- start_brk %lx", current->mm->start_brk); 446 kdebug("- brk %lx", current->mm->brk); 447 kdebug("- start_stack %lx", current->mm->start_stack); 448 449 #ifdef ELF_FDPIC_PLAT_INIT 450 /* 451 * The ABI may specify that certain registers be set up in special 452 * ways (on i386 %edx is the address of a DT_FINI function, for 453 * example. This macro performs whatever initialization to 454 * the regs structure is required. 455 */ 456 dynaddr = interp_params.dynamic_addr ?: exec_params.dynamic_addr; 457 ELF_FDPIC_PLAT_INIT(regs, exec_params.map_addr, interp_params.map_addr, 458 dynaddr); 459 #endif 460 461 finalize_exec(bprm); 462 /* everything is now ready... get the userspace context ready to roll */ 463 entryaddr = interp_params.entry_addr ?: exec_params.entry_addr; 464 start_thread(regs, entryaddr, current->mm->start_stack); 465 466 retval = 0; 467 468 error: 469 if (interpreter) { 470 allow_write_access(interpreter); 471 fput(interpreter); 472 } 473 kfree(interpreter_name); 474 kfree(exec_params.phdrs); 475 kfree(exec_params.loadmap); 476 kfree(interp_params.phdrs); 477 kfree(interp_params.loadmap); 478 return retval; 479 } 480 481 /*****************************************************************************/ 482 483 #ifndef ELF_BASE_PLATFORM 484 /* 485 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture. 486 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value 487 * will be copied to the user stack in the same manner as AT_PLATFORM. 488 */ 489 #define ELF_BASE_PLATFORM NULL 490 #endif 491 492 /* 493 * present useful information to the program by shovelling it onto the new 494 * process's stack 495 */ 496 static int create_elf_fdpic_tables(struct linux_binprm *bprm, 497 struct mm_struct *mm, 498 struct elf_fdpic_params *exec_params, 499 struct elf_fdpic_params *interp_params) 500 { 501 const struct cred *cred = current_cred(); 502 unsigned long sp, csp, nitems; 503 elf_caddr_t __user *argv, *envp; 504 size_t platform_len = 0, len; 505 char *k_platform, *k_base_platform; 506 char __user *u_platform, *u_base_platform, *p; 507 int loop; 508 int nr; /* reset for each csp adjustment */ 509 510 #ifdef CONFIG_MMU 511 /* In some cases (e.g. Hyper-Threading), we want to avoid L1 evictions 512 * by the processes running on the same package. One thing we can do is 513 * to shuffle the initial stack for them, so we give the architecture 514 * an opportunity to do so here. 515 */ 516 sp = arch_align_stack(bprm->p); 517 #else 518 sp = mm->start_stack; 519 520 /* stack the program arguments and environment */ 521 if (transfer_args_to_stack(bprm, &sp) < 0) 522 return -EFAULT; 523 sp &= ~15; 524 #endif 525 526 /* 527 * If this architecture has a platform capability string, copy it 528 * to userspace. In some cases (Sparc), this info is impossible 529 * for userspace to get any other way, in others (i386) it is 530 * merely difficult. 531 */ 532 k_platform = ELF_PLATFORM; 533 u_platform = NULL; 534 535 if (k_platform) { 536 platform_len = strlen(k_platform) + 1; 537 sp -= platform_len; 538 u_platform = (char __user *) sp; 539 if (copy_to_user(u_platform, k_platform, platform_len) != 0) 540 return -EFAULT; 541 } 542 543 /* 544 * If this architecture has a "base" platform capability 545 * string, copy it to userspace. 546 */ 547 k_base_platform = ELF_BASE_PLATFORM; 548 u_base_platform = NULL; 549 550 if (k_base_platform) { 551 platform_len = strlen(k_base_platform) + 1; 552 sp -= platform_len; 553 u_base_platform = (char __user *) sp; 554 if (copy_to_user(u_base_platform, k_base_platform, platform_len) != 0) 555 return -EFAULT; 556 } 557 558 sp &= ~7UL; 559 560 /* stack the load map(s) */ 561 len = sizeof(struct elf32_fdpic_loadmap); 562 len += sizeof(struct elf32_fdpic_loadseg) * exec_params->loadmap->nsegs; 563 sp = (sp - len) & ~7UL; 564 exec_params->map_addr = sp; 565 566 if (copy_to_user((void __user *) sp, exec_params->loadmap, len) != 0) 567 return -EFAULT; 568 569 current->mm->context.exec_fdpic_loadmap = (unsigned long) sp; 570 571 if (interp_params->loadmap) { 572 len = sizeof(struct elf32_fdpic_loadmap); 573 len += sizeof(struct elf32_fdpic_loadseg) * 574 interp_params->loadmap->nsegs; 575 sp = (sp - len) & ~7UL; 576 interp_params->map_addr = sp; 577 578 if (copy_to_user((void __user *) sp, interp_params->loadmap, 579 len) != 0) 580 return -EFAULT; 581 582 current->mm->context.interp_fdpic_loadmap = (unsigned long) sp; 583 } 584 585 /* force 16 byte _final_ alignment here for generality */ 586 #define DLINFO_ITEMS 15 587 588 nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) + 589 (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH; 590 591 if (bprm->have_execfd) 592 nitems++; 593 594 csp = sp; 595 sp -= nitems * 2 * sizeof(unsigned long); 596 sp -= (bprm->envc + 1) * sizeof(char *); /* envv[] */ 597 sp -= (bprm->argc + 1) * sizeof(char *); /* argv[] */ 598 sp -= 1 * sizeof(unsigned long); /* argc */ 599 600 csp -= sp & 15UL; 601 sp -= sp & 15UL; 602 603 /* put the ELF interpreter info on the stack */ 604 #define NEW_AUX_ENT(id, val) \ 605 do { \ 606 struct { unsigned long _id, _val; } __user *ent, v; \ 607 \ 608 ent = (void __user *) csp; \ 609 v._id = (id); \ 610 v._val = (val); \ 611 if (copy_to_user(ent + nr, &v, sizeof(v))) \ 612 return -EFAULT; \ 613 nr++; \ 614 } while (0) 615 616 nr = 0; 617 csp -= 2 * sizeof(unsigned long); 618 NEW_AUX_ENT(AT_NULL, 0); 619 if (k_platform) { 620 nr = 0; 621 csp -= 2 * sizeof(unsigned long); 622 NEW_AUX_ENT(AT_PLATFORM, 623 (elf_addr_t) (unsigned long) u_platform); 624 } 625 626 if (k_base_platform) { 627 nr = 0; 628 csp -= 2 * sizeof(unsigned long); 629 NEW_AUX_ENT(AT_BASE_PLATFORM, 630 (elf_addr_t) (unsigned long) u_base_platform); 631 } 632 633 if (bprm->have_execfd) { 634 nr = 0; 635 csp -= 2 * sizeof(unsigned long); 636 NEW_AUX_ENT(AT_EXECFD, bprm->execfd); 637 } 638 639 nr = 0; 640 csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long); 641 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP); 642 #ifdef ELF_HWCAP2 643 NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2); 644 #endif 645 NEW_AUX_ENT(AT_PAGESZ, PAGE_SIZE); 646 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC); 647 NEW_AUX_ENT(AT_PHDR, exec_params->ph_addr); 648 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); 649 NEW_AUX_ENT(AT_PHNUM, exec_params->hdr.e_phnum); 650 NEW_AUX_ENT(AT_BASE, interp_params->elfhdr_addr); 651 NEW_AUX_ENT(AT_FLAGS, 0); 652 NEW_AUX_ENT(AT_ENTRY, exec_params->entry_addr); 653 NEW_AUX_ENT(AT_UID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->uid)); 654 NEW_AUX_ENT(AT_EUID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->euid)); 655 NEW_AUX_ENT(AT_GID, (elf_addr_t) from_kgid_munged(cred->user_ns, cred->gid)); 656 NEW_AUX_ENT(AT_EGID, (elf_addr_t) from_kgid_munged(cred->user_ns, cred->egid)); 657 NEW_AUX_ENT(AT_SECURE, bprm->secureexec); 658 NEW_AUX_ENT(AT_EXECFN, bprm->exec); 659 660 #ifdef ARCH_DLINFO 661 nr = 0; 662 csp -= AT_VECTOR_SIZE_ARCH * 2 * sizeof(unsigned long); 663 664 /* ARCH_DLINFO must come last so platform specific code can enforce 665 * special alignment requirements on the AUXV if necessary (eg. PPC). 666 */ 667 ARCH_DLINFO; 668 #endif 669 #undef NEW_AUX_ENT 670 671 /* allocate room for argv[] and envv[] */ 672 csp -= (bprm->envc + 1) * sizeof(elf_caddr_t); 673 envp = (elf_caddr_t __user *) csp; 674 csp -= (bprm->argc + 1) * sizeof(elf_caddr_t); 675 argv = (elf_caddr_t __user *) csp; 676 677 /* stack argc */ 678 csp -= sizeof(unsigned long); 679 if (put_user(bprm->argc, (unsigned long __user *) csp)) 680 return -EFAULT; 681 682 BUG_ON(csp != sp); 683 684 /* fill in the argv[] array */ 685 #ifdef CONFIG_MMU 686 current->mm->arg_start = bprm->p; 687 #else 688 current->mm->arg_start = current->mm->start_stack - 689 (MAX_ARG_PAGES * PAGE_SIZE - bprm->p); 690 #endif 691 692 p = (char __user *) current->mm->arg_start; 693 for (loop = bprm->argc; loop > 0; loop--) { 694 if (put_user((elf_caddr_t) p, argv++)) 695 return -EFAULT; 696 len = strnlen_user(p, MAX_ARG_STRLEN); 697 if (!len || len > MAX_ARG_STRLEN) 698 return -EINVAL; 699 p += len; 700 } 701 if (put_user(NULL, argv)) 702 return -EFAULT; 703 current->mm->arg_end = (unsigned long) p; 704 705 /* fill in the envv[] array */ 706 current->mm->env_start = (unsigned long) p; 707 for (loop = bprm->envc; loop > 0; loop--) { 708 if (put_user((elf_caddr_t)(unsigned long) p, envp++)) 709 return -EFAULT; 710 len = strnlen_user(p, MAX_ARG_STRLEN); 711 if (!len || len > MAX_ARG_STRLEN) 712 return -EINVAL; 713 p += len; 714 } 715 if (put_user(NULL, envp)) 716 return -EFAULT; 717 current->mm->env_end = (unsigned long) p; 718 719 mm->start_stack = (unsigned long) sp; 720 return 0; 721 } 722 723 /*****************************************************************************/ 724 /* 725 * load the appropriate binary image (executable or interpreter) into memory 726 * - we assume no MMU is available 727 * - if no other PIC bits are set in params->hdr->e_flags 728 * - we assume that the LOADable segments in the binary are independently relocatable 729 * - we assume R/O executable segments are shareable 730 * - else 731 * - we assume the loadable parts of the image to require fixed displacement 732 * - the image is not shareable 733 */ 734 static int elf_fdpic_map_file(struct elf_fdpic_params *params, 735 struct file *file, 736 struct mm_struct *mm, 737 const char *what) 738 { 739 struct elf32_fdpic_loadmap *loadmap; 740 #ifdef CONFIG_MMU 741 struct elf32_fdpic_loadseg *mseg; 742 #endif 743 struct elf32_fdpic_loadseg *seg; 744 struct elf32_phdr *phdr; 745 unsigned long load_addr, stop; 746 unsigned nloads, tmp; 747 size_t size; 748 int loop, ret; 749 750 /* allocate a load map table */ 751 nloads = 0; 752 for (loop = 0; loop < params->hdr.e_phnum; loop++) 753 if (params->phdrs[loop].p_type == PT_LOAD) 754 nloads++; 755 756 if (nloads == 0) 757 return -ELIBBAD; 758 759 size = sizeof(*loadmap) + nloads * sizeof(*seg); 760 loadmap = kzalloc(size, GFP_KERNEL); 761 if (!loadmap) 762 return -ENOMEM; 763 764 params->loadmap = loadmap; 765 766 loadmap->version = ELF32_FDPIC_LOADMAP_VERSION; 767 loadmap->nsegs = nloads; 768 769 load_addr = params->load_addr; 770 seg = loadmap->segs; 771 772 /* map the requested LOADs into the memory space */ 773 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) { 774 case ELF_FDPIC_FLAG_CONSTDISP: 775 case ELF_FDPIC_FLAG_CONTIGUOUS: 776 #ifndef CONFIG_MMU 777 ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm); 778 if (ret < 0) 779 return ret; 780 break; 781 #endif 782 default: 783 ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm); 784 if (ret < 0) 785 return ret; 786 break; 787 } 788 789 /* map the entry point */ 790 if (params->hdr.e_entry) { 791 seg = loadmap->segs; 792 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) { 793 if (params->hdr.e_entry >= seg->p_vaddr && 794 params->hdr.e_entry < seg->p_vaddr + seg->p_memsz) { 795 params->entry_addr = 796 (params->hdr.e_entry - seg->p_vaddr) + 797 seg->addr; 798 break; 799 } 800 } 801 } 802 803 /* determine where the program header table has wound up if mapped */ 804 stop = params->hdr.e_phoff; 805 stop += params->hdr.e_phnum * sizeof (struct elf_phdr); 806 phdr = params->phdrs; 807 808 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 809 if (phdr->p_type != PT_LOAD) 810 continue; 811 812 if (phdr->p_offset > params->hdr.e_phoff || 813 phdr->p_offset + phdr->p_filesz < stop) 814 continue; 815 816 seg = loadmap->segs; 817 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) { 818 if (phdr->p_vaddr >= seg->p_vaddr && 819 phdr->p_vaddr + phdr->p_filesz <= 820 seg->p_vaddr + seg->p_memsz) { 821 params->ph_addr = 822 (phdr->p_vaddr - seg->p_vaddr) + 823 seg->addr + 824 params->hdr.e_phoff - phdr->p_offset; 825 break; 826 } 827 } 828 break; 829 } 830 831 /* determine where the dynamic section has wound up if there is one */ 832 phdr = params->phdrs; 833 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 834 if (phdr->p_type != PT_DYNAMIC) 835 continue; 836 837 seg = loadmap->segs; 838 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) { 839 if (phdr->p_vaddr >= seg->p_vaddr && 840 phdr->p_vaddr + phdr->p_memsz <= 841 seg->p_vaddr + seg->p_memsz) { 842 Elf32_Dyn __user *dyn; 843 Elf32_Sword d_tag; 844 845 params->dynamic_addr = 846 (phdr->p_vaddr - seg->p_vaddr) + 847 seg->addr; 848 849 /* check the dynamic section contains at least 850 * one item, and that the last item is a NULL 851 * entry */ 852 if (phdr->p_memsz == 0 || 853 phdr->p_memsz % sizeof(Elf32_Dyn) != 0) 854 goto dynamic_error; 855 856 tmp = phdr->p_memsz / sizeof(Elf32_Dyn); 857 dyn = (Elf32_Dyn __user *)params->dynamic_addr; 858 if (get_user(d_tag, &dyn[tmp - 1].d_tag) || 859 d_tag != 0) 860 goto dynamic_error; 861 break; 862 } 863 } 864 break; 865 } 866 867 /* now elide adjacent segments in the load map on MMU linux 868 * - on uClinux the holes between may actually be filled with system 869 * stuff or stuff from other processes 870 */ 871 #ifdef CONFIG_MMU 872 nloads = loadmap->nsegs; 873 mseg = loadmap->segs; 874 seg = mseg + 1; 875 for (loop = 1; loop < nloads; loop++) { 876 /* see if we have a candidate for merging */ 877 if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) { 878 load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz); 879 if (load_addr == (seg->addr & PAGE_MASK)) { 880 mseg->p_memsz += 881 load_addr - 882 (mseg->addr + mseg->p_memsz); 883 mseg->p_memsz += seg->addr & ~PAGE_MASK; 884 mseg->p_memsz += seg->p_memsz; 885 loadmap->nsegs--; 886 continue; 887 } 888 } 889 890 mseg++; 891 if (mseg != seg) 892 *mseg = *seg; 893 } 894 #endif 895 896 kdebug("Mapped Object [%s]:", what); 897 kdebug("- elfhdr : %lx", params->elfhdr_addr); 898 kdebug("- entry : %lx", params->entry_addr); 899 kdebug("- PHDR[] : %lx", params->ph_addr); 900 kdebug("- DYNAMIC[]: %lx", params->dynamic_addr); 901 seg = loadmap->segs; 902 for (loop = 0; loop < loadmap->nsegs; loop++, seg++) 903 kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]", 904 loop, 905 seg->addr, seg->addr + seg->p_memsz - 1, 906 seg->p_vaddr, seg->p_memsz); 907 908 return 0; 909 910 dynamic_error: 911 printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n", 912 what, file_inode(file)->i_ino); 913 return -ELIBBAD; 914 } 915 916 /*****************************************************************************/ 917 /* 918 * map a file with constant displacement under uClinux 919 */ 920 #ifndef CONFIG_MMU 921 static int elf_fdpic_map_file_constdisp_on_uclinux( 922 struct elf_fdpic_params *params, 923 struct file *file, 924 struct mm_struct *mm) 925 { 926 struct elf32_fdpic_loadseg *seg; 927 struct elf32_phdr *phdr; 928 unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags; 929 int loop, ret; 930 931 load_addr = params->load_addr; 932 seg = params->loadmap->segs; 933 934 /* determine the bounds of the contiguous overall allocation we must 935 * make */ 936 phdr = params->phdrs; 937 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) { 938 if (params->phdrs[loop].p_type != PT_LOAD) 939 continue; 940 941 if (base > phdr->p_vaddr) 942 base = phdr->p_vaddr; 943 if (top < phdr->p_vaddr + phdr->p_memsz) 944 top = phdr->p_vaddr + phdr->p_memsz; 945 } 946 947 /* allocate one big anon block for everything */ 948 mflags = MAP_PRIVATE; 949 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE) 950 mflags |= MAP_EXECUTABLE; 951 952 maddr = vm_mmap(NULL, load_addr, top - base, 953 PROT_READ | PROT_WRITE | PROT_EXEC, mflags, 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 | MAP_DENYWRITE; 1046 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE) 1047 flags |= MAP_EXECUTABLE; 1048 1049 maddr = 0; 1050 1051 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) { 1052 case ELF_FDPIC_FLAG_INDEPENDENT: 1053 /* PT_LOADs are independently locatable */ 1054 break; 1055 1056 case ELF_FDPIC_FLAG_HONOURVADDR: 1057 /* the specified virtual address must be honoured */ 1058 maddr = phdr->p_vaddr; 1059 flags |= MAP_FIXED; 1060 break; 1061 1062 case ELF_FDPIC_FLAG_CONSTDISP: 1063 /* constant displacement 1064 * - can be mapped anywhere, but must be mapped as a 1065 * unit 1066 */ 1067 if (!dvset) { 1068 maddr = load_addr; 1069 delta_vaddr = phdr->p_vaddr; 1070 dvset = 1; 1071 } else { 1072 maddr = load_addr + phdr->p_vaddr - delta_vaddr; 1073 flags |= MAP_FIXED; 1074 } 1075 break; 1076 1077 case ELF_FDPIC_FLAG_CONTIGUOUS: 1078 /* contiguity handled later */ 1079 break; 1080 1081 default: 1082 BUG(); 1083 } 1084 1085 maddr &= PAGE_MASK; 1086 1087 /* create the mapping */ 1088 disp = phdr->p_vaddr & ~PAGE_MASK; 1089 maddr = vm_mmap(file, maddr, phdr->p_memsz + disp, prot, flags, 1090 phdr->p_offset - disp); 1091 1092 kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx", 1093 loop, phdr->p_memsz + disp, prot, flags, 1094 phdr->p_offset - disp, maddr); 1095 1096 if (IS_ERR_VALUE(maddr)) 1097 return (int) maddr; 1098 1099 if ((params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) == 1100 ELF_FDPIC_FLAG_CONTIGUOUS) 1101 load_addr += PAGE_ALIGN(phdr->p_memsz + disp); 1102 1103 seg->addr = maddr + disp; 1104 seg->p_vaddr = phdr->p_vaddr; 1105 seg->p_memsz = phdr->p_memsz; 1106 1107 /* map the ELF header address if in this segment */ 1108 if (phdr->p_offset == 0) 1109 params->elfhdr_addr = seg->addr; 1110 1111 /* clear the bit between beginning of mapping and beginning of 1112 * PT_LOAD */ 1113 if (prot & PROT_WRITE && disp > 0) { 1114 kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp); 1115 if (clear_user((void __user *) maddr, disp)) 1116 return -EFAULT; 1117 maddr += disp; 1118 } 1119 1120 /* clear any space allocated but not loaded 1121 * - on uClinux we can just clear the lot 1122 * - on MMU linux we'll get a SIGBUS beyond the last page 1123 * extant in the file 1124 */ 1125 excess = phdr->p_memsz - phdr->p_filesz; 1126 excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK); 1127 1128 #ifdef CONFIG_MMU 1129 if (excess > excess1) { 1130 unsigned long xaddr = maddr + phdr->p_filesz + excess1; 1131 unsigned long xmaddr; 1132 1133 flags |= MAP_FIXED | MAP_ANONYMOUS; 1134 xmaddr = vm_mmap(NULL, xaddr, excess - excess1, 1135 prot, flags, 0); 1136 1137 kdebug("mmap[%d] <anon>" 1138 " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx", 1139 loop, xaddr, excess - excess1, prot, flags, 1140 xmaddr); 1141 1142 if (xmaddr != xaddr) 1143 return -ENOMEM; 1144 } 1145 1146 if (prot & PROT_WRITE && excess1 > 0) { 1147 kdebug("clear[%d] ad=%lx sz=%lx", 1148 loop, maddr + phdr->p_filesz, excess1); 1149 if (clear_user((void __user *) maddr + phdr->p_filesz, 1150 excess1)) 1151 return -EFAULT; 1152 } 1153 1154 #else 1155 if (excess > 0) { 1156 kdebug("clear[%d] ad=%lx sz=%lx", 1157 loop, maddr + phdr->p_filesz, excess); 1158 if (clear_user((void *) maddr + phdr->p_filesz, excess)) 1159 return -EFAULT; 1160 } 1161 #endif 1162 1163 if (mm) { 1164 if (phdr->p_flags & PF_X) { 1165 if (!mm->start_code) { 1166 mm->start_code = maddr; 1167 mm->end_code = maddr + phdr->p_memsz; 1168 } 1169 } else if (!mm->start_data) { 1170 mm->start_data = maddr; 1171 mm->end_data = maddr + phdr->p_memsz; 1172 } 1173 } 1174 1175 seg++; 1176 } 1177 1178 return 0; 1179 } 1180 1181 /*****************************************************************************/ 1182 /* 1183 * ELF-FDPIC core dumper 1184 * 1185 * Modelled on fs/exec.c:aout_core_dump() 1186 * Jeremy Fitzhardinge <jeremy@sw.oz.au> 1187 * 1188 * Modelled on fs/binfmt_elf.c core dumper 1189 */ 1190 #ifdef CONFIG_ELF_CORE 1191 1192 struct elf_prstatus_fdpic 1193 { 1194 struct elf_siginfo pr_info; /* Info associated with signal */ 1195 short pr_cursig; /* Current signal */ 1196 unsigned long pr_sigpend; /* Set of pending signals */ 1197 unsigned long pr_sighold; /* Set of held signals */ 1198 pid_t pr_pid; 1199 pid_t pr_ppid; 1200 pid_t pr_pgrp; 1201 pid_t pr_sid; 1202 struct __kernel_old_timeval pr_utime; /* User time */ 1203 struct __kernel_old_timeval pr_stime; /* System time */ 1204 struct __kernel_old_timeval pr_cutime; /* Cumulative user time */ 1205 struct __kernel_old_timeval pr_cstime; /* Cumulative system time */ 1206 elf_gregset_t pr_reg; /* GP registers */ 1207 /* When using FDPIC, the loadmap addresses need to be communicated 1208 * to GDB in order for GDB to do the necessary relocations. The 1209 * fields (below) used to communicate this information are placed 1210 * immediately after ``pr_reg'', so that the loadmap addresses may 1211 * be viewed as part of the register set if so desired. 1212 */ 1213 unsigned long pr_exec_fdpic_loadmap; 1214 unsigned long pr_interp_fdpic_loadmap; 1215 int pr_fpvalid; /* True if math co-processor being used. */ 1216 }; 1217 1218 /* An ELF note in memory */ 1219 struct memelfnote 1220 { 1221 const char *name; 1222 int type; 1223 unsigned int datasz; 1224 void *data; 1225 }; 1226 1227 static int notesize(struct memelfnote *en) 1228 { 1229 int sz; 1230 1231 sz = sizeof(struct elf_note); 1232 sz += roundup(strlen(en->name) + 1, 4); 1233 sz += roundup(en->datasz, 4); 1234 1235 return sz; 1236 } 1237 1238 /* #define DEBUG */ 1239 1240 static int writenote(struct memelfnote *men, struct coredump_params *cprm) 1241 { 1242 struct elf_note en; 1243 en.n_namesz = strlen(men->name) + 1; 1244 en.n_descsz = men->datasz; 1245 en.n_type = men->type; 1246 1247 return dump_emit(cprm, &en, sizeof(en)) && 1248 dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) && 1249 dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4); 1250 } 1251 1252 static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs) 1253 { 1254 memcpy(elf->e_ident, ELFMAG, SELFMAG); 1255 elf->e_ident[EI_CLASS] = ELF_CLASS; 1256 elf->e_ident[EI_DATA] = ELF_DATA; 1257 elf->e_ident[EI_VERSION] = EV_CURRENT; 1258 elf->e_ident[EI_OSABI] = ELF_OSABI; 1259 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); 1260 1261 elf->e_type = ET_CORE; 1262 elf->e_machine = ELF_ARCH; 1263 elf->e_version = EV_CURRENT; 1264 elf->e_entry = 0; 1265 elf->e_phoff = sizeof(struct elfhdr); 1266 elf->e_shoff = 0; 1267 elf->e_flags = ELF_FDPIC_CORE_EFLAGS; 1268 elf->e_ehsize = sizeof(struct elfhdr); 1269 elf->e_phentsize = sizeof(struct elf_phdr); 1270 elf->e_phnum = segs; 1271 elf->e_shentsize = 0; 1272 elf->e_shnum = 0; 1273 elf->e_shstrndx = 0; 1274 return; 1275 } 1276 1277 static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset) 1278 { 1279 phdr->p_type = PT_NOTE; 1280 phdr->p_offset = offset; 1281 phdr->p_vaddr = 0; 1282 phdr->p_paddr = 0; 1283 phdr->p_filesz = sz; 1284 phdr->p_memsz = 0; 1285 phdr->p_flags = 0; 1286 phdr->p_align = 0; 1287 return; 1288 } 1289 1290 static inline void fill_note(struct memelfnote *note, const char *name, int type, 1291 unsigned int sz, void *data) 1292 { 1293 note->name = name; 1294 note->type = type; 1295 note->datasz = sz; 1296 note->data = data; 1297 return; 1298 } 1299 1300 /* 1301 * fill up all the fields in prstatus from the given task struct, except 1302 * registers which need to be filled up separately. 1303 */ 1304 static void fill_prstatus(struct elf_prstatus_fdpic *prstatus, 1305 struct task_struct *p, long signr) 1306 { 1307 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr; 1308 prstatus->pr_sigpend = p->pending.signal.sig[0]; 1309 prstatus->pr_sighold = p->blocked.sig[0]; 1310 rcu_read_lock(); 1311 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); 1312 rcu_read_unlock(); 1313 prstatus->pr_pid = task_pid_vnr(p); 1314 prstatus->pr_pgrp = task_pgrp_vnr(p); 1315 prstatus->pr_sid = task_session_vnr(p); 1316 if (thread_group_leader(p)) { 1317 struct task_cputime cputime; 1318 1319 /* 1320 * This is the record for the group leader. It shows the 1321 * group-wide total, not its individual thread total. 1322 */ 1323 thread_group_cputime(p, &cputime); 1324 prstatus->pr_utime = ns_to_kernel_old_timeval(cputime.utime); 1325 prstatus->pr_stime = ns_to_kernel_old_timeval(cputime.stime); 1326 } else { 1327 u64 utime, stime; 1328 1329 task_cputime(p, &utime, &stime); 1330 prstatus->pr_utime = ns_to_kernel_old_timeval(utime); 1331 prstatus->pr_stime = ns_to_kernel_old_timeval(stime); 1332 } 1333 prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime); 1334 prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime); 1335 1336 prstatus->pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap; 1337 prstatus->pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap; 1338 } 1339 1340 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, 1341 struct mm_struct *mm) 1342 { 1343 const struct cred *cred; 1344 unsigned int i, len; 1345 1346 /* first copy the parameters from user space */ 1347 memset(psinfo, 0, sizeof(struct elf_prpsinfo)); 1348 1349 len = mm->arg_end - mm->arg_start; 1350 if (len >= ELF_PRARGSZ) 1351 len = ELF_PRARGSZ - 1; 1352 if (copy_from_user(&psinfo->pr_psargs, 1353 (const char __user *) mm->arg_start, len)) 1354 return -EFAULT; 1355 for (i = 0; i < len; i++) 1356 if (psinfo->pr_psargs[i] == 0) 1357 psinfo->pr_psargs[i] = ' '; 1358 psinfo->pr_psargs[len] = 0; 1359 1360 rcu_read_lock(); 1361 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); 1362 rcu_read_unlock(); 1363 psinfo->pr_pid = task_pid_vnr(p); 1364 psinfo->pr_pgrp = task_pgrp_vnr(p); 1365 psinfo->pr_sid = task_session_vnr(p); 1366 1367 i = p->state ? ffz(~p->state) + 1 : 0; 1368 psinfo->pr_state = i; 1369 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i]; 1370 psinfo->pr_zomb = psinfo->pr_sname == 'Z'; 1371 psinfo->pr_nice = task_nice(p); 1372 psinfo->pr_flag = p->flags; 1373 rcu_read_lock(); 1374 cred = __task_cred(p); 1375 SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid)); 1376 SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid)); 1377 rcu_read_unlock(); 1378 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); 1379 1380 return 0; 1381 } 1382 1383 /* Here is the structure in which status of each thread is captured. */ 1384 struct elf_thread_status 1385 { 1386 struct elf_thread_status *next; 1387 struct elf_prstatus_fdpic prstatus; /* NT_PRSTATUS */ 1388 elf_fpregset_t fpu; /* NT_PRFPREG */ 1389 struct memelfnote notes[2]; 1390 int num_notes; 1391 }; 1392 1393 /* 1394 * In order to add the specific thread information for the elf file format, 1395 * we need to keep a linked list of every thread's pr_status and then create 1396 * a single section for them in the final core file. 1397 */ 1398 static struct elf_thread_status *elf_dump_thread_status(long signr, struct task_struct *p, int *sz) 1399 { 1400 const struct user_regset_view *view = task_user_regset_view(p); 1401 struct elf_thread_status *t; 1402 int i, ret; 1403 1404 t = kzalloc(sizeof(struct elf_thread_status), GFP_KERNEL); 1405 if (!t) 1406 return t; 1407 1408 fill_prstatus(&t->prstatus, p, signr); 1409 regset_get(p, &view->regsets[0], 1410 sizeof(t->prstatus.pr_reg), &t->prstatus.pr_reg); 1411 1412 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), 1413 &t->prstatus); 1414 t->num_notes++; 1415 *sz += notesize(&t->notes[0]); 1416 1417 for (i = 1; i < view->n; ++i) { 1418 const struct user_regset *regset = &view->regsets[i]; 1419 if (regset->core_note_type != NT_PRFPREG) 1420 continue; 1421 if (regset->active && regset->active(p, regset) <= 0) 1422 continue; 1423 ret = regset_get(p, regset, sizeof(t->fpu), &t->fpu); 1424 if (ret >= 0) 1425 t->prstatus.pr_fpvalid = 1; 1426 break; 1427 } 1428 1429 if (t->prstatus.pr_fpvalid) { 1430 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), 1431 &t->fpu); 1432 t->num_notes++; 1433 *sz += notesize(&t->notes[1]); 1434 } 1435 return t; 1436 } 1437 1438 static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum, 1439 elf_addr_t e_shoff, int segs) 1440 { 1441 elf->e_shoff = e_shoff; 1442 elf->e_shentsize = sizeof(*shdr4extnum); 1443 elf->e_shnum = 1; 1444 elf->e_shstrndx = SHN_UNDEF; 1445 1446 memset(shdr4extnum, 0, sizeof(*shdr4extnum)); 1447 1448 shdr4extnum->sh_type = SHT_NULL; 1449 shdr4extnum->sh_size = elf->e_shnum; 1450 shdr4extnum->sh_link = elf->e_shstrndx; 1451 shdr4extnum->sh_info = segs; 1452 } 1453 1454 /* 1455 * dump the segments for an MMU process 1456 */ 1457 static bool elf_fdpic_dump_segments(struct coredump_params *cprm, 1458 struct core_vma_metadata *vma_meta, 1459 int vma_count) 1460 { 1461 int i; 1462 1463 for (i = 0; i < vma_count; i++) { 1464 struct core_vma_metadata *meta = vma_meta + i; 1465 1466 if (!dump_user_range(cprm, meta->start, meta->dump_size)) 1467 return false; 1468 } 1469 return true; 1470 } 1471 1472 /* 1473 * Actual dumper 1474 * 1475 * This is a two-pass process; first we find the offsets of the bits, 1476 * and then they are actually written out. If we run out of core limit 1477 * we just truncate. 1478 */ 1479 static int elf_fdpic_core_dump(struct coredump_params *cprm) 1480 { 1481 int has_dumped = 0; 1482 int vma_count, segs; 1483 int i; 1484 struct elfhdr *elf = NULL; 1485 loff_t offset = 0, dataoff; 1486 struct memelfnote psinfo_note, auxv_note; 1487 struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */ 1488 struct elf_thread_status *thread_list = NULL; 1489 int thread_status_size = 0; 1490 elf_addr_t *auxv; 1491 struct elf_phdr *phdr4note = NULL; 1492 struct elf_shdr *shdr4extnum = NULL; 1493 Elf_Half e_phnum; 1494 elf_addr_t e_shoff; 1495 struct core_thread *ct; 1496 struct elf_thread_status *tmp; 1497 struct core_vma_metadata *vma_meta = NULL; 1498 size_t vma_data_size; 1499 1500 /* alloc memory for large data structures: too large to be on stack */ 1501 elf = kmalloc(sizeof(*elf), GFP_KERNEL); 1502 if (!elf) 1503 goto end_coredump; 1504 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL); 1505 if (!psinfo) 1506 goto end_coredump; 1507 1508 if (dump_vma_snapshot(cprm, &vma_count, &vma_meta, &vma_data_size)) 1509 goto end_coredump; 1510 1511 for (ct = current->mm->core_state->dumper.next; 1512 ct; ct = ct->next) { 1513 tmp = elf_dump_thread_status(cprm->siginfo->si_signo, 1514 ct->task, &thread_status_size); 1515 if (!tmp) 1516 goto end_coredump; 1517 1518 tmp->next = thread_list; 1519 thread_list = tmp; 1520 } 1521 1522 /* now collect the dump for the current */ 1523 tmp = elf_dump_thread_status(cprm->siginfo->si_signo, 1524 current, &thread_status_size); 1525 if (!tmp) 1526 goto end_coredump; 1527 tmp->next = thread_list; 1528 thread_list = tmp; 1529 1530 segs = vma_count + elf_core_extra_phdrs(); 1531 1532 /* for notes section */ 1533 segs++; 1534 1535 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid 1536 * this, kernel supports extended numbering. Have a look at 1537 * include/linux/elf.h for further information. */ 1538 e_phnum = segs > PN_XNUM ? PN_XNUM : segs; 1539 1540 /* Set up header */ 1541 fill_elf_fdpic_header(elf, e_phnum); 1542 1543 has_dumped = 1; 1544 /* 1545 * Set up the notes in similar form to SVR4 core dumps made 1546 * with info from their /proc. 1547 */ 1548 1549 fill_psinfo(psinfo, current->group_leader, current->mm); 1550 fill_note(&psinfo_note, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo); 1551 thread_status_size += notesize(&psinfo_note); 1552 1553 auxv = (elf_addr_t *) current->mm->saved_auxv; 1554 i = 0; 1555 do 1556 i += 2; 1557 while (auxv[i - 2] != AT_NULL); 1558 fill_note(&auxv_note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv); 1559 thread_status_size += notesize(&auxv_note); 1560 1561 offset = sizeof(*elf); /* Elf header */ 1562 offset += segs * sizeof(struct elf_phdr); /* Program headers */ 1563 1564 /* Write notes phdr entry */ 1565 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL); 1566 if (!phdr4note) 1567 goto end_coredump; 1568 1569 fill_elf_note_phdr(phdr4note, thread_status_size, offset); 1570 offset += thread_status_size; 1571 1572 /* Page-align dumped data */ 1573 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); 1574 1575 offset += vma_data_size; 1576 offset += elf_core_extra_data_size(); 1577 e_shoff = offset; 1578 1579 if (e_phnum == PN_XNUM) { 1580 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL); 1581 if (!shdr4extnum) 1582 goto end_coredump; 1583 fill_extnum_info(elf, shdr4extnum, e_shoff, segs); 1584 } 1585 1586 offset = dataoff; 1587 1588 if (!dump_emit(cprm, elf, sizeof(*elf))) 1589 goto end_coredump; 1590 1591 if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note))) 1592 goto end_coredump; 1593 1594 /* write program headers for segments dump */ 1595 for (i = 0; i < vma_count; i++) { 1596 struct core_vma_metadata *meta = vma_meta + i; 1597 struct elf_phdr phdr; 1598 size_t sz; 1599 1600 sz = meta->end - meta->start; 1601 1602 phdr.p_type = PT_LOAD; 1603 phdr.p_offset = offset; 1604 phdr.p_vaddr = meta->start; 1605 phdr.p_paddr = 0; 1606 phdr.p_filesz = meta->dump_size; 1607 phdr.p_memsz = sz; 1608 offset += phdr.p_filesz; 1609 phdr.p_flags = 0; 1610 if (meta->flags & VM_READ) 1611 phdr.p_flags |= PF_R; 1612 if (meta->flags & VM_WRITE) 1613 phdr.p_flags |= PF_W; 1614 if (meta->flags & VM_EXEC) 1615 phdr.p_flags |= PF_X; 1616 phdr.p_align = ELF_EXEC_PAGESIZE; 1617 1618 if (!dump_emit(cprm, &phdr, sizeof(phdr))) 1619 goto end_coredump; 1620 } 1621 1622 if (!elf_core_write_extra_phdrs(cprm, offset)) 1623 goto end_coredump; 1624 1625 /* write out the notes section */ 1626 if (!writenote(thread_list->notes, cprm)) 1627 goto end_coredump; 1628 if (!writenote(&psinfo_note, cprm)) 1629 goto end_coredump; 1630 if (!writenote(&auxv_note, cprm)) 1631 goto end_coredump; 1632 for (i = 1; i < thread_list->num_notes; i++) 1633 if (!writenote(thread_list->notes + i, cprm)) 1634 goto end_coredump; 1635 1636 /* write out the thread status notes section */ 1637 for (tmp = thread_list->next; tmp; tmp = tmp->next) { 1638 for (i = 0; i < tmp->num_notes; i++) 1639 if (!writenote(&tmp->notes[i], cprm)) 1640 goto end_coredump; 1641 } 1642 1643 if (!dump_skip(cprm, dataoff - cprm->pos)) 1644 goto end_coredump; 1645 1646 if (!elf_fdpic_dump_segments(cprm, vma_meta, vma_count)) 1647 goto end_coredump; 1648 1649 if (!elf_core_write_extra_data(cprm)) 1650 goto end_coredump; 1651 1652 if (e_phnum == PN_XNUM) { 1653 if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum))) 1654 goto end_coredump; 1655 } 1656 1657 if (cprm->file->f_pos != offset) { 1658 /* Sanity check */ 1659 printk(KERN_WARNING 1660 "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n", 1661 cprm->file->f_pos, offset); 1662 } 1663 1664 end_coredump: 1665 while (thread_list) { 1666 tmp = thread_list; 1667 thread_list = thread_list->next; 1668 kfree(tmp); 1669 } 1670 kvfree(vma_meta); 1671 kfree(phdr4note); 1672 kfree(elf); 1673 kfree(psinfo); 1674 kfree(shdr4extnum); 1675 return has_dumped; 1676 } 1677 1678 #endif /* CONFIG_ELF_CORE */ 1679