1 /* 2 * linux/fs/binfmt_elf.c 3 * 4 * These are the functions used to load ELF format executables as used 5 * on SVr4 machines. Information on the format may be found in the book 6 * "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support 7 * Tools". 8 * 9 * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com). 10 */ 11 12 #include <linux/module.h> 13 #include <linux/kernel.h> 14 #include <linux/fs.h> 15 #include <linux/mm.h> 16 #include <linux/mman.h> 17 #include <linux/errno.h> 18 #include <linux/signal.h> 19 #include <linux/binfmts.h> 20 #include <linux/string.h> 21 #include <linux/file.h> 22 #include <linux/slab.h> 23 #include <linux/personality.h> 24 #include <linux/elfcore.h> 25 #include <linux/init.h> 26 #include <linux/highuid.h> 27 #include <linux/compiler.h> 28 #include <linux/highmem.h> 29 #include <linux/pagemap.h> 30 #include <linux/security.h> 31 #include <linux/random.h> 32 #include <linux/elf.h> 33 #include <linux/utsname.h> 34 #include <linux/coredump.h> 35 #include <asm/uaccess.h> 36 #include <asm/param.h> 37 #include <asm/page.h> 38 #include <asm/exec.h> 39 40 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs); 41 static int load_elf_library(struct file *); 42 static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *, 43 int, int, unsigned long); 44 45 /* 46 * If we don't support core dumping, then supply a NULL so we 47 * don't even try. 48 */ 49 #ifdef CONFIG_ELF_CORE 50 static int elf_core_dump(struct coredump_params *cprm); 51 #else 52 #define elf_core_dump NULL 53 #endif 54 55 #if ELF_EXEC_PAGESIZE > PAGE_SIZE 56 #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE 57 #else 58 #define ELF_MIN_ALIGN PAGE_SIZE 59 #endif 60 61 #ifndef ELF_CORE_EFLAGS 62 #define ELF_CORE_EFLAGS 0 63 #endif 64 65 #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1)) 66 #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1)) 67 #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1)) 68 69 static struct linux_binfmt elf_format = { 70 .module = THIS_MODULE, 71 .load_binary = load_elf_binary, 72 .load_shlib = load_elf_library, 73 .core_dump = elf_core_dump, 74 .min_coredump = ELF_EXEC_PAGESIZE, 75 }; 76 77 #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE) 78 79 static int set_brk(unsigned long start, unsigned long end) 80 { 81 start = ELF_PAGEALIGN(start); 82 end = ELF_PAGEALIGN(end); 83 if (end > start) { 84 unsigned long addr; 85 down_write(¤t->mm->mmap_sem); 86 addr = do_brk(start, end - start); 87 up_write(¤t->mm->mmap_sem); 88 if (BAD_ADDR(addr)) 89 return addr; 90 } 91 current->mm->start_brk = current->mm->brk = end; 92 return 0; 93 } 94 95 /* We need to explicitly zero any fractional pages 96 after the data section (i.e. bss). This would 97 contain the junk from the file that should not 98 be in memory 99 */ 100 static int padzero(unsigned long elf_bss) 101 { 102 unsigned long nbyte; 103 104 nbyte = ELF_PAGEOFFSET(elf_bss); 105 if (nbyte) { 106 nbyte = ELF_MIN_ALIGN - nbyte; 107 if (clear_user((void __user *) elf_bss, nbyte)) 108 return -EFAULT; 109 } 110 return 0; 111 } 112 113 /* Let's use some macros to make this stack manipulation a little clearer */ 114 #ifdef CONFIG_STACK_GROWSUP 115 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items)) 116 #define STACK_ROUND(sp, items) \ 117 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL) 118 #define STACK_ALLOC(sp, len) ({ \ 119 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \ 120 old_sp; }) 121 #else 122 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items)) 123 #define STACK_ROUND(sp, items) \ 124 (((unsigned long) (sp - items)) &~ 15UL) 125 #define STACK_ALLOC(sp, len) ({ sp -= len ; sp; }) 126 #endif 127 128 #ifndef ELF_BASE_PLATFORM 129 /* 130 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture. 131 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value 132 * will be copied to the user stack in the same manner as AT_PLATFORM. 133 */ 134 #define ELF_BASE_PLATFORM NULL 135 #endif 136 137 static int 138 create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec, 139 unsigned long load_addr, unsigned long interp_load_addr) 140 { 141 unsigned long p = bprm->p; 142 int argc = bprm->argc; 143 int envc = bprm->envc; 144 elf_addr_t __user *argv; 145 elf_addr_t __user *envp; 146 elf_addr_t __user *sp; 147 elf_addr_t __user *u_platform; 148 elf_addr_t __user *u_base_platform; 149 elf_addr_t __user *u_rand_bytes; 150 const char *k_platform = ELF_PLATFORM; 151 const char *k_base_platform = ELF_BASE_PLATFORM; 152 unsigned char k_rand_bytes[16]; 153 int items; 154 elf_addr_t *elf_info; 155 int ei_index = 0; 156 const struct cred *cred = current_cred(); 157 struct vm_area_struct *vma; 158 159 /* 160 * In some cases (e.g. Hyper-Threading), we want to avoid L1 161 * evictions by the processes running on the same package. One 162 * thing we can do is to shuffle the initial stack for them. 163 */ 164 165 p = arch_align_stack(p); 166 167 /* 168 * If this architecture has a platform capability string, copy it 169 * to userspace. In some cases (Sparc), this info is impossible 170 * for userspace to get any other way, in others (i386) it is 171 * merely difficult. 172 */ 173 u_platform = NULL; 174 if (k_platform) { 175 size_t len = strlen(k_platform) + 1; 176 177 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); 178 if (__copy_to_user(u_platform, k_platform, len)) 179 return -EFAULT; 180 } 181 182 /* 183 * If this architecture has a "base" platform capability 184 * string, copy it to userspace. 185 */ 186 u_base_platform = NULL; 187 if (k_base_platform) { 188 size_t len = strlen(k_base_platform) + 1; 189 190 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); 191 if (__copy_to_user(u_base_platform, k_base_platform, len)) 192 return -EFAULT; 193 } 194 195 /* 196 * Generate 16 random bytes for userspace PRNG seeding. 197 */ 198 get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes)); 199 u_rand_bytes = (elf_addr_t __user *) 200 STACK_ALLOC(p, sizeof(k_rand_bytes)); 201 if (__copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes))) 202 return -EFAULT; 203 204 /* Create the ELF interpreter info */ 205 elf_info = (elf_addr_t *)current->mm->saved_auxv; 206 /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */ 207 #define NEW_AUX_ENT(id, val) \ 208 do { \ 209 elf_info[ei_index++] = id; \ 210 elf_info[ei_index++] = val; \ 211 } while (0) 212 213 #ifdef ARCH_DLINFO 214 /* 215 * ARCH_DLINFO must come first so PPC can do its special alignment of 216 * AUXV. 217 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in 218 * ARCH_DLINFO changes 219 */ 220 ARCH_DLINFO; 221 #endif 222 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP); 223 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE); 224 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC); 225 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff); 226 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); 227 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum); 228 NEW_AUX_ENT(AT_BASE, interp_load_addr); 229 NEW_AUX_ENT(AT_FLAGS, 0); 230 NEW_AUX_ENT(AT_ENTRY, exec->e_entry); 231 NEW_AUX_ENT(AT_UID, cred->uid); 232 NEW_AUX_ENT(AT_EUID, cred->euid); 233 NEW_AUX_ENT(AT_GID, cred->gid); 234 NEW_AUX_ENT(AT_EGID, cred->egid); 235 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm)); 236 NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes); 237 NEW_AUX_ENT(AT_EXECFN, bprm->exec); 238 if (k_platform) { 239 NEW_AUX_ENT(AT_PLATFORM, 240 (elf_addr_t)(unsigned long)u_platform); 241 } 242 if (k_base_platform) { 243 NEW_AUX_ENT(AT_BASE_PLATFORM, 244 (elf_addr_t)(unsigned long)u_base_platform); 245 } 246 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) { 247 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data); 248 } 249 #undef NEW_AUX_ENT 250 /* AT_NULL is zero; clear the rest too */ 251 memset(&elf_info[ei_index], 0, 252 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]); 253 254 /* And advance past the AT_NULL entry. */ 255 ei_index += 2; 256 257 sp = STACK_ADD(p, ei_index); 258 259 items = (argc + 1) + (envc + 1) + 1; 260 bprm->p = STACK_ROUND(sp, items); 261 262 /* Point sp at the lowest address on the stack */ 263 #ifdef CONFIG_STACK_GROWSUP 264 sp = (elf_addr_t __user *)bprm->p - items - ei_index; 265 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */ 266 #else 267 sp = (elf_addr_t __user *)bprm->p; 268 #endif 269 270 271 /* 272 * Grow the stack manually; some architectures have a limit on how 273 * far ahead a user-space access may be in order to grow the stack. 274 */ 275 vma = find_extend_vma(current->mm, bprm->p); 276 if (!vma) 277 return -EFAULT; 278 279 /* Now, let's put argc (and argv, envp if appropriate) on the stack */ 280 if (__put_user(argc, sp++)) 281 return -EFAULT; 282 argv = sp; 283 envp = argv + argc + 1; 284 285 /* Populate argv and envp */ 286 p = current->mm->arg_end = current->mm->arg_start; 287 while (argc-- > 0) { 288 size_t len; 289 if (__put_user((elf_addr_t)p, argv++)) 290 return -EFAULT; 291 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); 292 if (!len || len > MAX_ARG_STRLEN) 293 return -EINVAL; 294 p += len; 295 } 296 if (__put_user(0, argv)) 297 return -EFAULT; 298 current->mm->arg_end = current->mm->env_start = p; 299 while (envc-- > 0) { 300 size_t len; 301 if (__put_user((elf_addr_t)p, envp++)) 302 return -EFAULT; 303 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); 304 if (!len || len > MAX_ARG_STRLEN) 305 return -EINVAL; 306 p += len; 307 } 308 if (__put_user(0, envp)) 309 return -EFAULT; 310 current->mm->env_end = p; 311 312 /* Put the elf_info on the stack in the right place. */ 313 sp = (elf_addr_t __user *)envp + 1; 314 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t))) 315 return -EFAULT; 316 return 0; 317 } 318 319 static unsigned long elf_map(struct file *filep, unsigned long addr, 320 struct elf_phdr *eppnt, int prot, int type, 321 unsigned long total_size) 322 { 323 unsigned long map_addr; 324 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr); 325 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr); 326 addr = ELF_PAGESTART(addr); 327 size = ELF_PAGEALIGN(size); 328 329 /* mmap() will return -EINVAL if given a zero size, but a 330 * segment with zero filesize is perfectly valid */ 331 if (!size) 332 return addr; 333 334 down_write(¤t->mm->mmap_sem); 335 /* 336 * total_size is the size of the ELF (interpreter) image. 337 * The _first_ mmap needs to know the full size, otherwise 338 * randomization might put this image into an overlapping 339 * position with the ELF binary image. (since size < total_size) 340 * So we first map the 'big' image - and unmap the remainder at 341 * the end. (which unmap is needed for ELF images with holes.) 342 */ 343 if (total_size) { 344 total_size = ELF_PAGEALIGN(total_size); 345 map_addr = do_mmap(filep, addr, total_size, prot, type, off); 346 if (!BAD_ADDR(map_addr)) 347 do_munmap(current->mm, map_addr+size, total_size-size); 348 } else 349 map_addr = do_mmap(filep, addr, size, prot, type, off); 350 351 up_write(¤t->mm->mmap_sem); 352 return(map_addr); 353 } 354 355 static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr) 356 { 357 int i, first_idx = -1, last_idx = -1; 358 359 for (i = 0; i < nr; i++) { 360 if (cmds[i].p_type == PT_LOAD) { 361 last_idx = i; 362 if (first_idx == -1) 363 first_idx = i; 364 } 365 } 366 if (first_idx == -1) 367 return 0; 368 369 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz - 370 ELF_PAGESTART(cmds[first_idx].p_vaddr); 371 } 372 373 374 /* This is much more generalized than the library routine read function, 375 so we keep this separate. Technically the library read function 376 is only provided so that we can read a.out libraries that have 377 an ELF header */ 378 379 static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex, 380 struct file *interpreter, unsigned long *interp_map_addr, 381 unsigned long no_base) 382 { 383 struct elf_phdr *elf_phdata; 384 struct elf_phdr *eppnt; 385 unsigned long load_addr = 0; 386 int load_addr_set = 0; 387 unsigned long last_bss = 0, elf_bss = 0; 388 unsigned long error = ~0UL; 389 unsigned long total_size; 390 int retval, i, size; 391 392 /* First of all, some simple consistency checks */ 393 if (interp_elf_ex->e_type != ET_EXEC && 394 interp_elf_ex->e_type != ET_DYN) 395 goto out; 396 if (!elf_check_arch(interp_elf_ex)) 397 goto out; 398 if (!interpreter->f_op || !interpreter->f_op->mmap) 399 goto out; 400 401 /* 402 * If the size of this structure has changed, then punt, since 403 * we will be doing the wrong thing. 404 */ 405 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr)) 406 goto out; 407 if (interp_elf_ex->e_phnum < 1 || 408 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr)) 409 goto out; 410 411 /* Now read in all of the header information */ 412 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum; 413 if (size > ELF_MIN_ALIGN) 414 goto out; 415 elf_phdata = kmalloc(size, GFP_KERNEL); 416 if (!elf_phdata) 417 goto out; 418 419 retval = kernel_read(interpreter, interp_elf_ex->e_phoff, 420 (char *)elf_phdata, size); 421 error = -EIO; 422 if (retval != size) { 423 if (retval < 0) 424 error = retval; 425 goto out_close; 426 } 427 428 total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum); 429 if (!total_size) { 430 error = -EINVAL; 431 goto out_close; 432 } 433 434 eppnt = elf_phdata; 435 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) { 436 if (eppnt->p_type == PT_LOAD) { 437 int elf_type = MAP_PRIVATE | MAP_DENYWRITE; 438 int elf_prot = 0; 439 unsigned long vaddr = 0; 440 unsigned long k, map_addr; 441 442 if (eppnt->p_flags & PF_R) 443 elf_prot = PROT_READ; 444 if (eppnt->p_flags & PF_W) 445 elf_prot |= PROT_WRITE; 446 if (eppnt->p_flags & PF_X) 447 elf_prot |= PROT_EXEC; 448 vaddr = eppnt->p_vaddr; 449 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set) 450 elf_type |= MAP_FIXED; 451 else if (no_base && interp_elf_ex->e_type == ET_DYN) 452 load_addr = -vaddr; 453 454 map_addr = elf_map(interpreter, load_addr + vaddr, 455 eppnt, elf_prot, elf_type, total_size); 456 total_size = 0; 457 if (!*interp_map_addr) 458 *interp_map_addr = map_addr; 459 error = map_addr; 460 if (BAD_ADDR(map_addr)) 461 goto out_close; 462 463 if (!load_addr_set && 464 interp_elf_ex->e_type == ET_DYN) { 465 load_addr = map_addr - ELF_PAGESTART(vaddr); 466 load_addr_set = 1; 467 } 468 469 /* 470 * Check to see if the section's size will overflow the 471 * allowed task size. Note that p_filesz must always be 472 * <= p_memsize so it's only necessary to check p_memsz. 473 */ 474 k = load_addr + eppnt->p_vaddr; 475 if (BAD_ADDR(k) || 476 eppnt->p_filesz > eppnt->p_memsz || 477 eppnt->p_memsz > TASK_SIZE || 478 TASK_SIZE - eppnt->p_memsz < k) { 479 error = -ENOMEM; 480 goto out_close; 481 } 482 483 /* 484 * Find the end of the file mapping for this phdr, and 485 * keep track of the largest address we see for this. 486 */ 487 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz; 488 if (k > elf_bss) 489 elf_bss = k; 490 491 /* 492 * Do the same thing for the memory mapping - between 493 * elf_bss and last_bss is the bss section. 494 */ 495 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr; 496 if (k > last_bss) 497 last_bss = k; 498 } 499 } 500 501 if (last_bss > elf_bss) { 502 /* 503 * Now fill out the bss section. First pad the last page up 504 * to the page boundary, and then perform a mmap to make sure 505 * that there are zero-mapped pages up to and including the 506 * last bss page. 507 */ 508 if (padzero(elf_bss)) { 509 error = -EFAULT; 510 goto out_close; 511 } 512 513 /* What we have mapped so far */ 514 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1); 515 516 /* Map the last of the bss segment */ 517 down_write(¤t->mm->mmap_sem); 518 error = do_brk(elf_bss, last_bss - elf_bss); 519 up_write(¤t->mm->mmap_sem); 520 if (BAD_ADDR(error)) 521 goto out_close; 522 } 523 524 error = load_addr; 525 526 out_close: 527 kfree(elf_phdata); 528 out: 529 return error; 530 } 531 532 /* 533 * These are the functions used to load ELF style executables and shared 534 * libraries. There is no binary dependent code anywhere else. 535 */ 536 537 #define INTERPRETER_NONE 0 538 #define INTERPRETER_ELF 2 539 540 #ifndef STACK_RND_MASK 541 #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */ 542 #endif 543 544 static unsigned long randomize_stack_top(unsigned long stack_top) 545 { 546 unsigned int random_variable = 0; 547 548 if ((current->flags & PF_RANDOMIZE) && 549 !(current->personality & ADDR_NO_RANDOMIZE)) { 550 random_variable = get_random_int() & STACK_RND_MASK; 551 random_variable <<= PAGE_SHIFT; 552 } 553 #ifdef CONFIG_STACK_GROWSUP 554 return PAGE_ALIGN(stack_top) + random_variable; 555 #else 556 return PAGE_ALIGN(stack_top) - random_variable; 557 #endif 558 } 559 560 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) 561 { 562 struct file *interpreter = NULL; /* to shut gcc up */ 563 unsigned long load_addr = 0, load_bias = 0; 564 int load_addr_set = 0; 565 char * elf_interpreter = NULL; 566 unsigned long error; 567 struct elf_phdr *elf_ppnt, *elf_phdata; 568 unsigned long elf_bss, elf_brk; 569 int retval, i; 570 unsigned int size; 571 unsigned long elf_entry; 572 unsigned long interp_load_addr = 0; 573 unsigned long start_code, end_code, start_data, end_data; 574 unsigned long reloc_func_desc __maybe_unused = 0; 575 int executable_stack = EXSTACK_DEFAULT; 576 unsigned long def_flags = 0; 577 struct { 578 struct elfhdr elf_ex; 579 struct elfhdr interp_elf_ex; 580 } *loc; 581 582 loc = kmalloc(sizeof(*loc), GFP_KERNEL); 583 if (!loc) { 584 retval = -ENOMEM; 585 goto out_ret; 586 } 587 588 /* Get the exec-header */ 589 loc->elf_ex = *((struct elfhdr *)bprm->buf); 590 591 retval = -ENOEXEC; 592 /* First of all, some simple consistency checks */ 593 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0) 594 goto out; 595 596 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN) 597 goto out; 598 if (!elf_check_arch(&loc->elf_ex)) 599 goto out; 600 if (!bprm->file->f_op || !bprm->file->f_op->mmap) 601 goto out; 602 603 /* Now read in all of the header information */ 604 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr)) 605 goto out; 606 if (loc->elf_ex.e_phnum < 1 || 607 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr)) 608 goto out; 609 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr); 610 retval = -ENOMEM; 611 elf_phdata = kmalloc(size, GFP_KERNEL); 612 if (!elf_phdata) 613 goto out; 614 615 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff, 616 (char *)elf_phdata, size); 617 if (retval != size) { 618 if (retval >= 0) 619 retval = -EIO; 620 goto out_free_ph; 621 } 622 623 elf_ppnt = elf_phdata; 624 elf_bss = 0; 625 elf_brk = 0; 626 627 start_code = ~0UL; 628 end_code = 0; 629 start_data = 0; 630 end_data = 0; 631 632 for (i = 0; i < loc->elf_ex.e_phnum; i++) { 633 if (elf_ppnt->p_type == PT_INTERP) { 634 /* This is the program interpreter used for 635 * shared libraries - for now assume that this 636 * is an a.out format binary 637 */ 638 retval = -ENOEXEC; 639 if (elf_ppnt->p_filesz > PATH_MAX || 640 elf_ppnt->p_filesz < 2) 641 goto out_free_ph; 642 643 retval = -ENOMEM; 644 elf_interpreter = kmalloc(elf_ppnt->p_filesz, 645 GFP_KERNEL); 646 if (!elf_interpreter) 647 goto out_free_ph; 648 649 retval = kernel_read(bprm->file, elf_ppnt->p_offset, 650 elf_interpreter, 651 elf_ppnt->p_filesz); 652 if (retval != elf_ppnt->p_filesz) { 653 if (retval >= 0) 654 retval = -EIO; 655 goto out_free_interp; 656 } 657 /* make sure path is NULL terminated */ 658 retval = -ENOEXEC; 659 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0') 660 goto out_free_interp; 661 662 interpreter = open_exec(elf_interpreter); 663 retval = PTR_ERR(interpreter); 664 if (IS_ERR(interpreter)) 665 goto out_free_interp; 666 667 /* 668 * If the binary is not readable then enforce 669 * mm->dumpable = 0 regardless of the interpreter's 670 * permissions. 671 */ 672 would_dump(bprm, interpreter); 673 674 retval = kernel_read(interpreter, 0, bprm->buf, 675 BINPRM_BUF_SIZE); 676 if (retval != BINPRM_BUF_SIZE) { 677 if (retval >= 0) 678 retval = -EIO; 679 goto out_free_dentry; 680 } 681 682 /* Get the exec headers */ 683 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf); 684 break; 685 } 686 elf_ppnt++; 687 } 688 689 elf_ppnt = elf_phdata; 690 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) 691 if (elf_ppnt->p_type == PT_GNU_STACK) { 692 if (elf_ppnt->p_flags & PF_X) 693 executable_stack = EXSTACK_ENABLE_X; 694 else 695 executable_stack = EXSTACK_DISABLE_X; 696 break; 697 } 698 699 /* Some simple consistency checks for the interpreter */ 700 if (elf_interpreter) { 701 retval = -ELIBBAD; 702 /* Not an ELF interpreter */ 703 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0) 704 goto out_free_dentry; 705 /* Verify the interpreter has a valid arch */ 706 if (!elf_check_arch(&loc->interp_elf_ex)) 707 goto out_free_dentry; 708 } 709 710 /* Flush all traces of the currently running executable */ 711 retval = flush_old_exec(bprm); 712 if (retval) 713 goto out_free_dentry; 714 715 /* OK, This is the point of no return */ 716 current->mm->def_flags = def_flags; 717 718 /* Do this immediately, since STACK_TOP as used in setup_arg_pages 719 may depend on the personality. */ 720 SET_PERSONALITY(loc->elf_ex); 721 if (elf_read_implies_exec(loc->elf_ex, executable_stack)) 722 current->personality |= READ_IMPLIES_EXEC; 723 724 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) 725 current->flags |= PF_RANDOMIZE; 726 727 setup_new_exec(bprm); 728 729 /* Do this so that we can load the interpreter, if need be. We will 730 change some of these later */ 731 current->mm->free_area_cache = current->mm->mmap_base; 732 current->mm->cached_hole_size = 0; 733 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP), 734 executable_stack); 735 if (retval < 0) { 736 send_sig(SIGKILL, current, 0); 737 goto out_free_dentry; 738 } 739 740 current->mm->start_stack = bprm->p; 741 742 /* Now we do a little grungy work by mmapping the ELF image into 743 the correct location in memory. */ 744 for(i = 0, elf_ppnt = elf_phdata; 745 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) { 746 int elf_prot = 0, elf_flags; 747 unsigned long k, vaddr; 748 749 if (elf_ppnt->p_type != PT_LOAD) 750 continue; 751 752 if (unlikely (elf_brk > elf_bss)) { 753 unsigned long nbyte; 754 755 /* There was a PT_LOAD segment with p_memsz > p_filesz 756 before this one. Map anonymous pages, if needed, 757 and clear the area. */ 758 retval = set_brk(elf_bss + load_bias, 759 elf_brk + load_bias); 760 if (retval) { 761 send_sig(SIGKILL, current, 0); 762 goto out_free_dentry; 763 } 764 nbyte = ELF_PAGEOFFSET(elf_bss); 765 if (nbyte) { 766 nbyte = ELF_MIN_ALIGN - nbyte; 767 if (nbyte > elf_brk - elf_bss) 768 nbyte = elf_brk - elf_bss; 769 if (clear_user((void __user *)elf_bss + 770 load_bias, nbyte)) { 771 /* 772 * This bss-zeroing can fail if the ELF 773 * file specifies odd protections. So 774 * we don't check the return value 775 */ 776 } 777 } 778 } 779 780 if (elf_ppnt->p_flags & PF_R) 781 elf_prot |= PROT_READ; 782 if (elf_ppnt->p_flags & PF_W) 783 elf_prot |= PROT_WRITE; 784 if (elf_ppnt->p_flags & PF_X) 785 elf_prot |= PROT_EXEC; 786 787 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE; 788 789 vaddr = elf_ppnt->p_vaddr; 790 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) { 791 elf_flags |= MAP_FIXED; 792 } else if (loc->elf_ex.e_type == ET_DYN) { 793 /* Try and get dynamic programs out of the way of the 794 * default mmap base, as well as whatever program they 795 * might try to exec. This is because the brk will 796 * follow the loader, and is not movable. */ 797 #ifdef CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE 798 /* Memory randomization might have been switched off 799 * in runtime via sysctl. 800 * If that is the case, retain the original non-zero 801 * load_bias value in order to establish proper 802 * non-randomized mappings. 803 */ 804 if (current->flags & PF_RANDOMIZE) 805 load_bias = 0; 806 else 807 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr); 808 #else 809 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr); 810 #endif 811 } 812 813 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt, 814 elf_prot, elf_flags, 0); 815 if (BAD_ADDR(error)) { 816 send_sig(SIGKILL, current, 0); 817 retval = IS_ERR((void *)error) ? 818 PTR_ERR((void*)error) : -EINVAL; 819 goto out_free_dentry; 820 } 821 822 if (!load_addr_set) { 823 load_addr_set = 1; 824 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset); 825 if (loc->elf_ex.e_type == ET_DYN) { 826 load_bias += error - 827 ELF_PAGESTART(load_bias + vaddr); 828 load_addr += load_bias; 829 reloc_func_desc = load_bias; 830 } 831 } 832 k = elf_ppnt->p_vaddr; 833 if (k < start_code) 834 start_code = k; 835 if (start_data < k) 836 start_data = k; 837 838 /* 839 * Check to see if the section's size will overflow the 840 * allowed task size. Note that p_filesz must always be 841 * <= p_memsz so it is only necessary to check p_memsz. 842 */ 843 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz || 844 elf_ppnt->p_memsz > TASK_SIZE || 845 TASK_SIZE - elf_ppnt->p_memsz < k) { 846 /* set_brk can never work. Avoid overflows. */ 847 send_sig(SIGKILL, current, 0); 848 retval = -EINVAL; 849 goto out_free_dentry; 850 } 851 852 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz; 853 854 if (k > elf_bss) 855 elf_bss = k; 856 if ((elf_ppnt->p_flags & PF_X) && end_code < k) 857 end_code = k; 858 if (end_data < k) 859 end_data = k; 860 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz; 861 if (k > elf_brk) 862 elf_brk = k; 863 } 864 865 loc->elf_ex.e_entry += load_bias; 866 elf_bss += load_bias; 867 elf_brk += load_bias; 868 start_code += load_bias; 869 end_code += load_bias; 870 start_data += load_bias; 871 end_data += load_bias; 872 873 /* Calling set_brk effectively mmaps the pages that we need 874 * for the bss and break sections. We must do this before 875 * mapping in the interpreter, to make sure it doesn't wind 876 * up getting placed where the bss needs to go. 877 */ 878 retval = set_brk(elf_bss, elf_brk); 879 if (retval) { 880 send_sig(SIGKILL, current, 0); 881 goto out_free_dentry; 882 } 883 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) { 884 send_sig(SIGSEGV, current, 0); 885 retval = -EFAULT; /* Nobody gets to see this, but.. */ 886 goto out_free_dentry; 887 } 888 889 if (elf_interpreter) { 890 unsigned long uninitialized_var(interp_map_addr); 891 892 elf_entry = load_elf_interp(&loc->interp_elf_ex, 893 interpreter, 894 &interp_map_addr, 895 load_bias); 896 if (!IS_ERR((void *)elf_entry)) { 897 /* 898 * load_elf_interp() returns relocation 899 * adjustment 900 */ 901 interp_load_addr = elf_entry; 902 elf_entry += loc->interp_elf_ex.e_entry; 903 } 904 if (BAD_ADDR(elf_entry)) { 905 force_sig(SIGSEGV, current); 906 retval = IS_ERR((void *)elf_entry) ? 907 (int)elf_entry : -EINVAL; 908 goto out_free_dentry; 909 } 910 reloc_func_desc = interp_load_addr; 911 912 allow_write_access(interpreter); 913 fput(interpreter); 914 kfree(elf_interpreter); 915 } else { 916 elf_entry = loc->elf_ex.e_entry; 917 if (BAD_ADDR(elf_entry)) { 918 force_sig(SIGSEGV, current); 919 retval = -EINVAL; 920 goto out_free_dentry; 921 } 922 } 923 924 kfree(elf_phdata); 925 926 set_binfmt(&elf_format); 927 928 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES 929 retval = arch_setup_additional_pages(bprm, !!elf_interpreter); 930 if (retval < 0) { 931 send_sig(SIGKILL, current, 0); 932 goto out; 933 } 934 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */ 935 936 install_exec_creds(bprm); 937 retval = create_elf_tables(bprm, &loc->elf_ex, 938 load_addr, interp_load_addr); 939 if (retval < 0) { 940 send_sig(SIGKILL, current, 0); 941 goto out; 942 } 943 /* N.B. passed_fileno might not be initialized? */ 944 current->mm->end_code = end_code; 945 current->mm->start_code = start_code; 946 current->mm->start_data = start_data; 947 current->mm->end_data = end_data; 948 current->mm->start_stack = bprm->p; 949 950 #ifdef arch_randomize_brk 951 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) { 952 current->mm->brk = current->mm->start_brk = 953 arch_randomize_brk(current->mm); 954 #ifdef CONFIG_COMPAT_BRK 955 current->brk_randomized = 1; 956 #endif 957 } 958 #endif 959 960 if (current->personality & MMAP_PAGE_ZERO) { 961 /* Why this, you ask??? Well SVr4 maps page 0 as read-only, 962 and some applications "depend" upon this behavior. 963 Since we do not have the power to recompile these, we 964 emulate the SVr4 behavior. Sigh. */ 965 down_write(¤t->mm->mmap_sem); 966 error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC, 967 MAP_FIXED | MAP_PRIVATE, 0); 968 up_write(¤t->mm->mmap_sem); 969 } 970 971 #ifdef ELF_PLAT_INIT 972 /* 973 * The ABI may specify that certain registers be set up in special 974 * ways (on i386 %edx is the address of a DT_FINI function, for 975 * example. In addition, it may also specify (eg, PowerPC64 ELF) 976 * that the e_entry field is the address of the function descriptor 977 * for the startup routine, rather than the address of the startup 978 * routine itself. This macro performs whatever initialization to 979 * the regs structure is required as well as any relocations to the 980 * function descriptor entries when executing dynamically links apps. 981 */ 982 ELF_PLAT_INIT(regs, reloc_func_desc); 983 #endif 984 985 start_thread(regs, elf_entry, bprm->p); 986 retval = 0; 987 out: 988 kfree(loc); 989 out_ret: 990 return retval; 991 992 /* error cleanup */ 993 out_free_dentry: 994 allow_write_access(interpreter); 995 if (interpreter) 996 fput(interpreter); 997 out_free_interp: 998 kfree(elf_interpreter); 999 out_free_ph: 1000 kfree(elf_phdata); 1001 goto out; 1002 } 1003 1004 /* This is really simpleminded and specialized - we are loading an 1005 a.out library that is given an ELF header. */ 1006 static int load_elf_library(struct file *file) 1007 { 1008 struct elf_phdr *elf_phdata; 1009 struct elf_phdr *eppnt; 1010 unsigned long elf_bss, bss, len; 1011 int retval, error, i, j; 1012 struct elfhdr elf_ex; 1013 1014 error = -ENOEXEC; 1015 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex)); 1016 if (retval != sizeof(elf_ex)) 1017 goto out; 1018 1019 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0) 1020 goto out; 1021 1022 /* First of all, some simple consistency checks */ 1023 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 || 1024 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap) 1025 goto out; 1026 1027 /* Now read in all of the header information */ 1028 1029 j = sizeof(struct elf_phdr) * elf_ex.e_phnum; 1030 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */ 1031 1032 error = -ENOMEM; 1033 elf_phdata = kmalloc(j, GFP_KERNEL); 1034 if (!elf_phdata) 1035 goto out; 1036 1037 eppnt = elf_phdata; 1038 error = -ENOEXEC; 1039 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j); 1040 if (retval != j) 1041 goto out_free_ph; 1042 1043 for (j = 0, i = 0; i<elf_ex.e_phnum; i++) 1044 if ((eppnt + i)->p_type == PT_LOAD) 1045 j++; 1046 if (j != 1) 1047 goto out_free_ph; 1048 1049 while (eppnt->p_type != PT_LOAD) 1050 eppnt++; 1051 1052 /* Now use mmap to map the library into memory. */ 1053 down_write(¤t->mm->mmap_sem); 1054 error = do_mmap(file, 1055 ELF_PAGESTART(eppnt->p_vaddr), 1056 (eppnt->p_filesz + 1057 ELF_PAGEOFFSET(eppnt->p_vaddr)), 1058 PROT_READ | PROT_WRITE | PROT_EXEC, 1059 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, 1060 (eppnt->p_offset - 1061 ELF_PAGEOFFSET(eppnt->p_vaddr))); 1062 up_write(¤t->mm->mmap_sem); 1063 if (error != ELF_PAGESTART(eppnt->p_vaddr)) 1064 goto out_free_ph; 1065 1066 elf_bss = eppnt->p_vaddr + eppnt->p_filesz; 1067 if (padzero(elf_bss)) { 1068 error = -EFAULT; 1069 goto out_free_ph; 1070 } 1071 1072 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr + 1073 ELF_MIN_ALIGN - 1); 1074 bss = eppnt->p_memsz + eppnt->p_vaddr; 1075 if (bss > len) { 1076 down_write(¤t->mm->mmap_sem); 1077 do_brk(len, bss - len); 1078 up_write(¤t->mm->mmap_sem); 1079 } 1080 error = 0; 1081 1082 out_free_ph: 1083 kfree(elf_phdata); 1084 out: 1085 return error; 1086 } 1087 1088 #ifdef CONFIG_ELF_CORE 1089 /* 1090 * ELF core dumper 1091 * 1092 * Modelled on fs/exec.c:aout_core_dump() 1093 * Jeremy Fitzhardinge <jeremy@sw.oz.au> 1094 */ 1095 1096 /* 1097 * Decide what to dump of a segment, part, all or none. 1098 */ 1099 static unsigned long vma_dump_size(struct vm_area_struct *vma, 1100 unsigned long mm_flags) 1101 { 1102 #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type)) 1103 1104 /* The vma can be set up to tell us the answer directly. */ 1105 if (vma->vm_flags & VM_ALWAYSDUMP) 1106 goto whole; 1107 1108 /* Hugetlb memory check */ 1109 if (vma->vm_flags & VM_HUGETLB) { 1110 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED)) 1111 goto whole; 1112 if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE)) 1113 goto whole; 1114 } 1115 1116 /* Do not dump I/O mapped devices or special mappings */ 1117 if (vma->vm_flags & (VM_IO | VM_RESERVED)) 1118 return 0; 1119 1120 /* By default, dump shared memory if mapped from an anonymous file. */ 1121 if (vma->vm_flags & VM_SHARED) { 1122 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ? 1123 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED)) 1124 goto whole; 1125 return 0; 1126 } 1127 1128 /* Dump segments that have been written to. */ 1129 if (vma->anon_vma && FILTER(ANON_PRIVATE)) 1130 goto whole; 1131 if (vma->vm_file == NULL) 1132 return 0; 1133 1134 if (FILTER(MAPPED_PRIVATE)) 1135 goto whole; 1136 1137 /* 1138 * If this looks like the beginning of a DSO or executable mapping, 1139 * check for an ELF header. If we find one, dump the first page to 1140 * aid in determining what was mapped here. 1141 */ 1142 if (FILTER(ELF_HEADERS) && 1143 vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) { 1144 u32 __user *header = (u32 __user *) vma->vm_start; 1145 u32 word; 1146 mm_segment_t fs = get_fs(); 1147 /* 1148 * Doing it this way gets the constant folded by GCC. 1149 */ 1150 union { 1151 u32 cmp; 1152 char elfmag[SELFMAG]; 1153 } magic; 1154 BUILD_BUG_ON(SELFMAG != sizeof word); 1155 magic.elfmag[EI_MAG0] = ELFMAG0; 1156 magic.elfmag[EI_MAG1] = ELFMAG1; 1157 magic.elfmag[EI_MAG2] = ELFMAG2; 1158 magic.elfmag[EI_MAG3] = ELFMAG3; 1159 /* 1160 * Switch to the user "segment" for get_user(), 1161 * then put back what elf_core_dump() had in place. 1162 */ 1163 set_fs(USER_DS); 1164 if (unlikely(get_user(word, header))) 1165 word = 0; 1166 set_fs(fs); 1167 if (word == magic.cmp) 1168 return PAGE_SIZE; 1169 } 1170 1171 #undef FILTER 1172 1173 return 0; 1174 1175 whole: 1176 return vma->vm_end - vma->vm_start; 1177 } 1178 1179 /* An ELF note in memory */ 1180 struct memelfnote 1181 { 1182 const char *name; 1183 int type; 1184 unsigned int datasz; 1185 void *data; 1186 }; 1187 1188 static int notesize(struct memelfnote *en) 1189 { 1190 int sz; 1191 1192 sz = sizeof(struct elf_note); 1193 sz += roundup(strlen(en->name) + 1, 4); 1194 sz += roundup(en->datasz, 4); 1195 1196 return sz; 1197 } 1198 1199 #define DUMP_WRITE(addr, nr, foffset) \ 1200 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0) 1201 1202 static int alignfile(struct file *file, loff_t *foffset) 1203 { 1204 static const char buf[4] = { 0, }; 1205 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset); 1206 return 1; 1207 } 1208 1209 static int writenote(struct memelfnote *men, struct file *file, 1210 loff_t *foffset) 1211 { 1212 struct elf_note en; 1213 en.n_namesz = strlen(men->name) + 1; 1214 en.n_descsz = men->datasz; 1215 en.n_type = men->type; 1216 1217 DUMP_WRITE(&en, sizeof(en), foffset); 1218 DUMP_WRITE(men->name, en.n_namesz, foffset); 1219 if (!alignfile(file, foffset)) 1220 return 0; 1221 DUMP_WRITE(men->data, men->datasz, foffset); 1222 if (!alignfile(file, foffset)) 1223 return 0; 1224 1225 return 1; 1226 } 1227 #undef DUMP_WRITE 1228 1229 static void fill_elf_header(struct elfhdr *elf, int segs, 1230 u16 machine, u32 flags, u8 osabi) 1231 { 1232 memset(elf, 0, sizeof(*elf)); 1233 1234 memcpy(elf->e_ident, ELFMAG, SELFMAG); 1235 elf->e_ident[EI_CLASS] = ELF_CLASS; 1236 elf->e_ident[EI_DATA] = ELF_DATA; 1237 elf->e_ident[EI_VERSION] = EV_CURRENT; 1238 elf->e_ident[EI_OSABI] = ELF_OSABI; 1239 1240 elf->e_type = ET_CORE; 1241 elf->e_machine = machine; 1242 elf->e_version = EV_CURRENT; 1243 elf->e_phoff = sizeof(struct elfhdr); 1244 elf->e_flags = flags; 1245 elf->e_ehsize = sizeof(struct elfhdr); 1246 elf->e_phentsize = sizeof(struct elf_phdr); 1247 elf->e_phnum = segs; 1248 1249 return; 1250 } 1251 1252 static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset) 1253 { 1254 phdr->p_type = PT_NOTE; 1255 phdr->p_offset = offset; 1256 phdr->p_vaddr = 0; 1257 phdr->p_paddr = 0; 1258 phdr->p_filesz = sz; 1259 phdr->p_memsz = 0; 1260 phdr->p_flags = 0; 1261 phdr->p_align = 0; 1262 return; 1263 } 1264 1265 static void fill_note(struct memelfnote *note, const char *name, int type, 1266 unsigned int sz, void *data) 1267 { 1268 note->name = name; 1269 note->type = type; 1270 note->datasz = sz; 1271 note->data = data; 1272 return; 1273 } 1274 1275 /* 1276 * fill up all the fields in prstatus from the given task struct, except 1277 * registers which need to be filled up separately. 1278 */ 1279 static void fill_prstatus(struct elf_prstatus *prstatus, 1280 struct task_struct *p, long signr) 1281 { 1282 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr; 1283 prstatus->pr_sigpend = p->pending.signal.sig[0]; 1284 prstatus->pr_sighold = p->blocked.sig[0]; 1285 rcu_read_lock(); 1286 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); 1287 rcu_read_unlock(); 1288 prstatus->pr_pid = task_pid_vnr(p); 1289 prstatus->pr_pgrp = task_pgrp_vnr(p); 1290 prstatus->pr_sid = task_session_vnr(p); 1291 if (thread_group_leader(p)) { 1292 struct task_cputime cputime; 1293 1294 /* 1295 * This is the record for the group leader. It shows the 1296 * group-wide total, not its individual thread total. 1297 */ 1298 thread_group_cputime(p, &cputime); 1299 cputime_to_timeval(cputime.utime, &prstatus->pr_utime); 1300 cputime_to_timeval(cputime.stime, &prstatus->pr_stime); 1301 } else { 1302 cputime_to_timeval(p->utime, &prstatus->pr_utime); 1303 cputime_to_timeval(p->stime, &prstatus->pr_stime); 1304 } 1305 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime); 1306 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime); 1307 } 1308 1309 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, 1310 struct mm_struct *mm) 1311 { 1312 const struct cred *cred; 1313 unsigned int i, len; 1314 1315 /* first copy the parameters from user space */ 1316 memset(psinfo, 0, sizeof(struct elf_prpsinfo)); 1317 1318 len = mm->arg_end - mm->arg_start; 1319 if (len >= ELF_PRARGSZ) 1320 len = ELF_PRARGSZ-1; 1321 if (copy_from_user(&psinfo->pr_psargs, 1322 (const char __user *)mm->arg_start, len)) 1323 return -EFAULT; 1324 for(i = 0; i < len; i++) 1325 if (psinfo->pr_psargs[i] == 0) 1326 psinfo->pr_psargs[i] = ' '; 1327 psinfo->pr_psargs[len] = 0; 1328 1329 rcu_read_lock(); 1330 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); 1331 rcu_read_unlock(); 1332 psinfo->pr_pid = task_pid_vnr(p); 1333 psinfo->pr_pgrp = task_pgrp_vnr(p); 1334 psinfo->pr_sid = task_session_vnr(p); 1335 1336 i = p->state ? ffz(~p->state) + 1 : 0; 1337 psinfo->pr_state = i; 1338 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i]; 1339 psinfo->pr_zomb = psinfo->pr_sname == 'Z'; 1340 psinfo->pr_nice = task_nice(p); 1341 psinfo->pr_flag = p->flags; 1342 rcu_read_lock(); 1343 cred = __task_cred(p); 1344 SET_UID(psinfo->pr_uid, cred->uid); 1345 SET_GID(psinfo->pr_gid, cred->gid); 1346 rcu_read_unlock(); 1347 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); 1348 1349 return 0; 1350 } 1351 1352 static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm) 1353 { 1354 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv; 1355 int i = 0; 1356 do 1357 i += 2; 1358 while (auxv[i - 2] != AT_NULL); 1359 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv); 1360 } 1361 1362 #ifdef CORE_DUMP_USE_REGSET 1363 #include <linux/regset.h> 1364 1365 struct elf_thread_core_info { 1366 struct elf_thread_core_info *next; 1367 struct task_struct *task; 1368 struct elf_prstatus prstatus; 1369 struct memelfnote notes[0]; 1370 }; 1371 1372 struct elf_note_info { 1373 struct elf_thread_core_info *thread; 1374 struct memelfnote psinfo; 1375 struct memelfnote auxv; 1376 size_t size; 1377 int thread_notes; 1378 }; 1379 1380 /* 1381 * When a regset has a writeback hook, we call it on each thread before 1382 * dumping user memory. On register window machines, this makes sure the 1383 * user memory backing the register data is up to date before we read it. 1384 */ 1385 static void do_thread_regset_writeback(struct task_struct *task, 1386 const struct user_regset *regset) 1387 { 1388 if (regset->writeback) 1389 regset->writeback(task, regset, 1); 1390 } 1391 1392 static int fill_thread_core_info(struct elf_thread_core_info *t, 1393 const struct user_regset_view *view, 1394 long signr, size_t *total) 1395 { 1396 unsigned int i; 1397 1398 /* 1399 * NT_PRSTATUS is the one special case, because the regset data 1400 * goes into the pr_reg field inside the note contents, rather 1401 * than being the whole note contents. We fill the reset in here. 1402 * We assume that regset 0 is NT_PRSTATUS. 1403 */ 1404 fill_prstatus(&t->prstatus, t->task, signr); 1405 (void) view->regsets[0].get(t->task, &view->regsets[0], 1406 0, sizeof(t->prstatus.pr_reg), 1407 &t->prstatus.pr_reg, NULL); 1408 1409 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, 1410 sizeof(t->prstatus), &t->prstatus); 1411 *total += notesize(&t->notes[0]); 1412 1413 do_thread_regset_writeback(t->task, &view->regsets[0]); 1414 1415 /* 1416 * Each other regset might generate a note too. For each regset 1417 * that has no core_note_type or is inactive, we leave t->notes[i] 1418 * all zero and we'll know to skip writing it later. 1419 */ 1420 for (i = 1; i < view->n; ++i) { 1421 const struct user_regset *regset = &view->regsets[i]; 1422 do_thread_regset_writeback(t->task, regset); 1423 if (regset->core_note_type && regset->get && 1424 (!regset->active || regset->active(t->task, regset))) { 1425 int ret; 1426 size_t size = regset->n * regset->size; 1427 void *data = kmalloc(size, GFP_KERNEL); 1428 if (unlikely(!data)) 1429 return 0; 1430 ret = regset->get(t->task, regset, 1431 0, size, data, NULL); 1432 if (unlikely(ret)) 1433 kfree(data); 1434 else { 1435 if (regset->core_note_type != NT_PRFPREG) 1436 fill_note(&t->notes[i], "LINUX", 1437 regset->core_note_type, 1438 size, data); 1439 else { 1440 t->prstatus.pr_fpvalid = 1; 1441 fill_note(&t->notes[i], "CORE", 1442 NT_PRFPREG, size, data); 1443 } 1444 *total += notesize(&t->notes[i]); 1445 } 1446 } 1447 } 1448 1449 return 1; 1450 } 1451 1452 static int fill_note_info(struct elfhdr *elf, int phdrs, 1453 struct elf_note_info *info, 1454 long signr, struct pt_regs *regs) 1455 { 1456 struct task_struct *dump_task = current; 1457 const struct user_regset_view *view = task_user_regset_view(dump_task); 1458 struct elf_thread_core_info *t; 1459 struct elf_prpsinfo *psinfo; 1460 struct core_thread *ct; 1461 unsigned int i; 1462 1463 info->size = 0; 1464 info->thread = NULL; 1465 1466 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL); 1467 if (psinfo == NULL) 1468 return 0; 1469 1470 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo); 1471 1472 /* 1473 * Figure out how many notes we're going to need for each thread. 1474 */ 1475 info->thread_notes = 0; 1476 for (i = 0; i < view->n; ++i) 1477 if (view->regsets[i].core_note_type != 0) 1478 ++info->thread_notes; 1479 1480 /* 1481 * Sanity check. We rely on regset 0 being in NT_PRSTATUS, 1482 * since it is our one special case. 1483 */ 1484 if (unlikely(info->thread_notes == 0) || 1485 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) { 1486 WARN_ON(1); 1487 return 0; 1488 } 1489 1490 /* 1491 * Initialize the ELF file header. 1492 */ 1493 fill_elf_header(elf, phdrs, 1494 view->e_machine, view->e_flags, view->ei_osabi); 1495 1496 /* 1497 * Allocate a structure for each thread. 1498 */ 1499 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) { 1500 t = kzalloc(offsetof(struct elf_thread_core_info, 1501 notes[info->thread_notes]), 1502 GFP_KERNEL); 1503 if (unlikely(!t)) 1504 return 0; 1505 1506 t->task = ct->task; 1507 if (ct->task == dump_task || !info->thread) { 1508 t->next = info->thread; 1509 info->thread = t; 1510 } else { 1511 /* 1512 * Make sure to keep the original task at 1513 * the head of the list. 1514 */ 1515 t->next = info->thread->next; 1516 info->thread->next = t; 1517 } 1518 } 1519 1520 /* 1521 * Now fill in each thread's information. 1522 */ 1523 for (t = info->thread; t != NULL; t = t->next) 1524 if (!fill_thread_core_info(t, view, signr, &info->size)) 1525 return 0; 1526 1527 /* 1528 * Fill in the two process-wide notes. 1529 */ 1530 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm); 1531 info->size += notesize(&info->psinfo); 1532 1533 fill_auxv_note(&info->auxv, current->mm); 1534 info->size += notesize(&info->auxv); 1535 1536 return 1; 1537 } 1538 1539 static size_t get_note_info_size(struct elf_note_info *info) 1540 { 1541 return info->size; 1542 } 1543 1544 /* 1545 * Write all the notes for each thread. When writing the first thread, the 1546 * process-wide notes are interleaved after the first thread-specific note. 1547 */ 1548 static int write_note_info(struct elf_note_info *info, 1549 struct file *file, loff_t *foffset) 1550 { 1551 bool first = 1; 1552 struct elf_thread_core_info *t = info->thread; 1553 1554 do { 1555 int i; 1556 1557 if (!writenote(&t->notes[0], file, foffset)) 1558 return 0; 1559 1560 if (first && !writenote(&info->psinfo, file, foffset)) 1561 return 0; 1562 if (first && !writenote(&info->auxv, file, foffset)) 1563 return 0; 1564 1565 for (i = 1; i < info->thread_notes; ++i) 1566 if (t->notes[i].data && 1567 !writenote(&t->notes[i], file, foffset)) 1568 return 0; 1569 1570 first = 0; 1571 t = t->next; 1572 } while (t); 1573 1574 return 1; 1575 } 1576 1577 static void free_note_info(struct elf_note_info *info) 1578 { 1579 struct elf_thread_core_info *threads = info->thread; 1580 while (threads) { 1581 unsigned int i; 1582 struct elf_thread_core_info *t = threads; 1583 threads = t->next; 1584 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus); 1585 for (i = 1; i < info->thread_notes; ++i) 1586 kfree(t->notes[i].data); 1587 kfree(t); 1588 } 1589 kfree(info->psinfo.data); 1590 } 1591 1592 #else 1593 1594 /* Here is the structure in which status of each thread is captured. */ 1595 struct elf_thread_status 1596 { 1597 struct list_head list; 1598 struct elf_prstatus prstatus; /* NT_PRSTATUS */ 1599 elf_fpregset_t fpu; /* NT_PRFPREG */ 1600 struct task_struct *thread; 1601 #ifdef ELF_CORE_COPY_XFPREGS 1602 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */ 1603 #endif 1604 struct memelfnote notes[3]; 1605 int num_notes; 1606 }; 1607 1608 /* 1609 * In order to add the specific thread information for the elf file format, 1610 * we need to keep a linked list of every threads pr_status and then create 1611 * a single section for them in the final core file. 1612 */ 1613 static int elf_dump_thread_status(long signr, struct elf_thread_status *t) 1614 { 1615 int sz = 0; 1616 struct task_struct *p = t->thread; 1617 t->num_notes = 0; 1618 1619 fill_prstatus(&t->prstatus, p, signr); 1620 elf_core_copy_task_regs(p, &t->prstatus.pr_reg); 1621 1622 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), 1623 &(t->prstatus)); 1624 t->num_notes++; 1625 sz += notesize(&t->notes[0]); 1626 1627 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, 1628 &t->fpu))) { 1629 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), 1630 &(t->fpu)); 1631 t->num_notes++; 1632 sz += notesize(&t->notes[1]); 1633 } 1634 1635 #ifdef ELF_CORE_COPY_XFPREGS 1636 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) { 1637 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE, 1638 sizeof(t->xfpu), &t->xfpu); 1639 t->num_notes++; 1640 sz += notesize(&t->notes[2]); 1641 } 1642 #endif 1643 return sz; 1644 } 1645 1646 struct elf_note_info { 1647 struct memelfnote *notes; 1648 struct elf_prstatus *prstatus; /* NT_PRSTATUS */ 1649 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */ 1650 struct list_head thread_list; 1651 elf_fpregset_t *fpu; 1652 #ifdef ELF_CORE_COPY_XFPREGS 1653 elf_fpxregset_t *xfpu; 1654 #endif 1655 int thread_status_size; 1656 int numnote; 1657 }; 1658 1659 static int elf_note_info_init(struct elf_note_info *info) 1660 { 1661 memset(info, 0, sizeof(*info)); 1662 INIT_LIST_HEAD(&info->thread_list); 1663 1664 /* Allocate space for six ELF notes */ 1665 info->notes = kmalloc(6 * sizeof(struct memelfnote), GFP_KERNEL); 1666 if (!info->notes) 1667 return 0; 1668 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL); 1669 if (!info->psinfo) 1670 goto notes_free; 1671 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL); 1672 if (!info->prstatus) 1673 goto psinfo_free; 1674 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL); 1675 if (!info->fpu) 1676 goto prstatus_free; 1677 #ifdef ELF_CORE_COPY_XFPREGS 1678 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL); 1679 if (!info->xfpu) 1680 goto fpu_free; 1681 #endif 1682 return 1; 1683 #ifdef ELF_CORE_COPY_XFPREGS 1684 fpu_free: 1685 kfree(info->fpu); 1686 #endif 1687 prstatus_free: 1688 kfree(info->prstatus); 1689 psinfo_free: 1690 kfree(info->psinfo); 1691 notes_free: 1692 kfree(info->notes); 1693 return 0; 1694 } 1695 1696 static int fill_note_info(struct elfhdr *elf, int phdrs, 1697 struct elf_note_info *info, 1698 long signr, struct pt_regs *regs) 1699 { 1700 struct list_head *t; 1701 1702 if (!elf_note_info_init(info)) 1703 return 0; 1704 1705 if (signr) { 1706 struct core_thread *ct; 1707 struct elf_thread_status *ets; 1708 1709 for (ct = current->mm->core_state->dumper.next; 1710 ct; ct = ct->next) { 1711 ets = kzalloc(sizeof(*ets), GFP_KERNEL); 1712 if (!ets) 1713 return 0; 1714 1715 ets->thread = ct->task; 1716 list_add(&ets->list, &info->thread_list); 1717 } 1718 1719 list_for_each(t, &info->thread_list) { 1720 int sz; 1721 1722 ets = list_entry(t, struct elf_thread_status, list); 1723 sz = elf_dump_thread_status(signr, ets); 1724 info->thread_status_size += sz; 1725 } 1726 } 1727 /* now collect the dump for the current */ 1728 memset(info->prstatus, 0, sizeof(*info->prstatus)); 1729 fill_prstatus(info->prstatus, current, signr); 1730 elf_core_copy_regs(&info->prstatus->pr_reg, regs); 1731 1732 /* Set up header */ 1733 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI); 1734 1735 /* 1736 * Set up the notes in similar form to SVR4 core dumps made 1737 * with info from their /proc. 1738 */ 1739 1740 fill_note(info->notes + 0, "CORE", NT_PRSTATUS, 1741 sizeof(*info->prstatus), info->prstatus); 1742 fill_psinfo(info->psinfo, current->group_leader, current->mm); 1743 fill_note(info->notes + 1, "CORE", NT_PRPSINFO, 1744 sizeof(*info->psinfo), info->psinfo); 1745 1746 info->numnote = 2; 1747 1748 fill_auxv_note(&info->notes[info->numnote++], current->mm); 1749 1750 /* Try to dump the FPU. */ 1751 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs, 1752 info->fpu); 1753 if (info->prstatus->pr_fpvalid) 1754 fill_note(info->notes + info->numnote++, 1755 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu); 1756 #ifdef ELF_CORE_COPY_XFPREGS 1757 if (elf_core_copy_task_xfpregs(current, info->xfpu)) 1758 fill_note(info->notes + info->numnote++, 1759 "LINUX", ELF_CORE_XFPREG_TYPE, 1760 sizeof(*info->xfpu), info->xfpu); 1761 #endif 1762 1763 return 1; 1764 } 1765 1766 static size_t get_note_info_size(struct elf_note_info *info) 1767 { 1768 int sz = 0; 1769 int i; 1770 1771 for (i = 0; i < info->numnote; i++) 1772 sz += notesize(info->notes + i); 1773 1774 sz += info->thread_status_size; 1775 1776 return sz; 1777 } 1778 1779 static int write_note_info(struct elf_note_info *info, 1780 struct file *file, loff_t *foffset) 1781 { 1782 int i; 1783 struct list_head *t; 1784 1785 for (i = 0; i < info->numnote; i++) 1786 if (!writenote(info->notes + i, file, foffset)) 1787 return 0; 1788 1789 /* write out the thread status notes section */ 1790 list_for_each(t, &info->thread_list) { 1791 struct elf_thread_status *tmp = 1792 list_entry(t, struct elf_thread_status, list); 1793 1794 for (i = 0; i < tmp->num_notes; i++) 1795 if (!writenote(&tmp->notes[i], file, foffset)) 1796 return 0; 1797 } 1798 1799 return 1; 1800 } 1801 1802 static void free_note_info(struct elf_note_info *info) 1803 { 1804 while (!list_empty(&info->thread_list)) { 1805 struct list_head *tmp = info->thread_list.next; 1806 list_del(tmp); 1807 kfree(list_entry(tmp, struct elf_thread_status, list)); 1808 } 1809 1810 kfree(info->prstatus); 1811 kfree(info->psinfo); 1812 kfree(info->notes); 1813 kfree(info->fpu); 1814 #ifdef ELF_CORE_COPY_XFPREGS 1815 kfree(info->xfpu); 1816 #endif 1817 } 1818 1819 #endif 1820 1821 static struct vm_area_struct *first_vma(struct task_struct *tsk, 1822 struct vm_area_struct *gate_vma) 1823 { 1824 struct vm_area_struct *ret = tsk->mm->mmap; 1825 1826 if (ret) 1827 return ret; 1828 return gate_vma; 1829 } 1830 /* 1831 * Helper function for iterating across a vma list. It ensures that the caller 1832 * will visit `gate_vma' prior to terminating the search. 1833 */ 1834 static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, 1835 struct vm_area_struct *gate_vma) 1836 { 1837 struct vm_area_struct *ret; 1838 1839 ret = this_vma->vm_next; 1840 if (ret) 1841 return ret; 1842 if (this_vma == gate_vma) 1843 return NULL; 1844 return gate_vma; 1845 } 1846 1847 static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum, 1848 elf_addr_t e_shoff, int segs) 1849 { 1850 elf->e_shoff = e_shoff; 1851 elf->e_shentsize = sizeof(*shdr4extnum); 1852 elf->e_shnum = 1; 1853 elf->e_shstrndx = SHN_UNDEF; 1854 1855 memset(shdr4extnum, 0, sizeof(*shdr4extnum)); 1856 1857 shdr4extnum->sh_type = SHT_NULL; 1858 shdr4extnum->sh_size = elf->e_shnum; 1859 shdr4extnum->sh_link = elf->e_shstrndx; 1860 shdr4extnum->sh_info = segs; 1861 } 1862 1863 static size_t elf_core_vma_data_size(struct vm_area_struct *gate_vma, 1864 unsigned long mm_flags) 1865 { 1866 struct vm_area_struct *vma; 1867 size_t size = 0; 1868 1869 for (vma = first_vma(current, gate_vma); vma != NULL; 1870 vma = next_vma(vma, gate_vma)) 1871 size += vma_dump_size(vma, mm_flags); 1872 return size; 1873 } 1874 1875 /* 1876 * Actual dumper 1877 * 1878 * This is a two-pass process; first we find the offsets of the bits, 1879 * and then they are actually written out. If we run out of core limit 1880 * we just truncate. 1881 */ 1882 static int elf_core_dump(struct coredump_params *cprm) 1883 { 1884 int has_dumped = 0; 1885 mm_segment_t fs; 1886 int segs; 1887 size_t size = 0; 1888 struct vm_area_struct *vma, *gate_vma; 1889 struct elfhdr *elf = NULL; 1890 loff_t offset = 0, dataoff, foffset; 1891 struct elf_note_info info; 1892 struct elf_phdr *phdr4note = NULL; 1893 struct elf_shdr *shdr4extnum = NULL; 1894 Elf_Half e_phnum; 1895 elf_addr_t e_shoff; 1896 1897 /* 1898 * We no longer stop all VM operations. 1899 * 1900 * This is because those proceses that could possibly change map_count 1901 * or the mmap / vma pages are now blocked in do_exit on current 1902 * finishing this core dump. 1903 * 1904 * Only ptrace can touch these memory addresses, but it doesn't change 1905 * the map_count or the pages allocated. So no possibility of crashing 1906 * exists while dumping the mm->vm_next areas to the core file. 1907 */ 1908 1909 /* alloc memory for large data structures: too large to be on stack */ 1910 elf = kmalloc(sizeof(*elf), GFP_KERNEL); 1911 if (!elf) 1912 goto out; 1913 /* 1914 * The number of segs are recored into ELF header as 16bit value. 1915 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here. 1916 */ 1917 segs = current->mm->map_count; 1918 segs += elf_core_extra_phdrs(); 1919 1920 gate_vma = get_gate_vma(current->mm); 1921 if (gate_vma != NULL) 1922 segs++; 1923 1924 /* for notes section */ 1925 segs++; 1926 1927 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid 1928 * this, kernel supports extended numbering. Have a look at 1929 * include/linux/elf.h for further information. */ 1930 e_phnum = segs > PN_XNUM ? PN_XNUM : segs; 1931 1932 /* 1933 * Collect all the non-memory information about the process for the 1934 * notes. This also sets up the file header. 1935 */ 1936 if (!fill_note_info(elf, e_phnum, &info, cprm->signr, cprm->regs)) 1937 goto cleanup; 1938 1939 has_dumped = 1; 1940 current->flags |= PF_DUMPCORE; 1941 1942 fs = get_fs(); 1943 set_fs(KERNEL_DS); 1944 1945 offset += sizeof(*elf); /* Elf header */ 1946 offset += segs * sizeof(struct elf_phdr); /* Program headers */ 1947 foffset = offset; 1948 1949 /* Write notes phdr entry */ 1950 { 1951 size_t sz = get_note_info_size(&info); 1952 1953 sz += elf_coredump_extra_notes_size(); 1954 1955 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL); 1956 if (!phdr4note) 1957 goto end_coredump; 1958 1959 fill_elf_note_phdr(phdr4note, sz, offset); 1960 offset += sz; 1961 } 1962 1963 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); 1964 1965 offset += elf_core_vma_data_size(gate_vma, cprm->mm_flags); 1966 offset += elf_core_extra_data_size(); 1967 e_shoff = offset; 1968 1969 if (e_phnum == PN_XNUM) { 1970 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL); 1971 if (!shdr4extnum) 1972 goto end_coredump; 1973 fill_extnum_info(elf, shdr4extnum, e_shoff, segs); 1974 } 1975 1976 offset = dataoff; 1977 1978 size += sizeof(*elf); 1979 if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf))) 1980 goto end_coredump; 1981 1982 size += sizeof(*phdr4note); 1983 if (size > cprm->limit 1984 || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note))) 1985 goto end_coredump; 1986 1987 /* Write program headers for segments dump */ 1988 for (vma = first_vma(current, gate_vma); vma != NULL; 1989 vma = next_vma(vma, gate_vma)) { 1990 struct elf_phdr phdr; 1991 1992 phdr.p_type = PT_LOAD; 1993 phdr.p_offset = offset; 1994 phdr.p_vaddr = vma->vm_start; 1995 phdr.p_paddr = 0; 1996 phdr.p_filesz = vma_dump_size(vma, cprm->mm_flags); 1997 phdr.p_memsz = vma->vm_end - vma->vm_start; 1998 offset += phdr.p_filesz; 1999 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0; 2000 if (vma->vm_flags & VM_WRITE) 2001 phdr.p_flags |= PF_W; 2002 if (vma->vm_flags & VM_EXEC) 2003 phdr.p_flags |= PF_X; 2004 phdr.p_align = ELF_EXEC_PAGESIZE; 2005 2006 size += sizeof(phdr); 2007 if (size > cprm->limit 2008 || !dump_write(cprm->file, &phdr, sizeof(phdr))) 2009 goto end_coredump; 2010 } 2011 2012 if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit)) 2013 goto end_coredump; 2014 2015 /* write out the notes section */ 2016 if (!write_note_info(&info, cprm->file, &foffset)) 2017 goto end_coredump; 2018 2019 if (elf_coredump_extra_notes_write(cprm->file, &foffset)) 2020 goto end_coredump; 2021 2022 /* Align to page */ 2023 if (!dump_seek(cprm->file, dataoff - foffset)) 2024 goto end_coredump; 2025 2026 for (vma = first_vma(current, gate_vma); vma != NULL; 2027 vma = next_vma(vma, gate_vma)) { 2028 unsigned long addr; 2029 unsigned long end; 2030 2031 end = vma->vm_start + vma_dump_size(vma, cprm->mm_flags); 2032 2033 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) { 2034 struct page *page; 2035 int stop; 2036 2037 page = get_dump_page(addr); 2038 if (page) { 2039 void *kaddr = kmap(page); 2040 stop = ((size += PAGE_SIZE) > cprm->limit) || 2041 !dump_write(cprm->file, kaddr, 2042 PAGE_SIZE); 2043 kunmap(page); 2044 page_cache_release(page); 2045 } else 2046 stop = !dump_seek(cprm->file, PAGE_SIZE); 2047 if (stop) 2048 goto end_coredump; 2049 } 2050 } 2051 2052 if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit)) 2053 goto end_coredump; 2054 2055 if (e_phnum == PN_XNUM) { 2056 size += sizeof(*shdr4extnum); 2057 if (size > cprm->limit 2058 || !dump_write(cprm->file, shdr4extnum, 2059 sizeof(*shdr4extnum))) 2060 goto end_coredump; 2061 } 2062 2063 end_coredump: 2064 set_fs(fs); 2065 2066 cleanup: 2067 free_note_info(&info); 2068 kfree(shdr4extnum); 2069 kfree(phdr4note); 2070 kfree(elf); 2071 out: 2072 return has_dumped; 2073 } 2074 2075 #endif /* CONFIG_ELF_CORE */ 2076 2077 static int __init init_elf_binfmt(void) 2078 { 2079 register_binfmt(&elf_format); 2080 return 0; 2081 } 2082 2083 static void __exit exit_elf_binfmt(void) 2084 { 2085 /* Remove the COFF and ELF loaders. */ 2086 unregister_binfmt(&elf_format); 2087 } 2088 2089 core_initcall(init_elf_binfmt); 2090 module_exit(exit_elf_binfmt); 2091 MODULE_LICENSE("GPL"); 2092