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 39 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs); 40 static int load_elf_library(struct file *); 41 static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *, 42 int, int, unsigned long); 43 44 /* 45 * If we don't support core dumping, then supply a NULL so we 46 * don't even try. 47 */ 48 #ifdef CONFIG_ELF_CORE 49 static int elf_core_dump(struct coredump_params *cprm); 50 #else 51 #define elf_core_dump NULL 52 #endif 53 54 #if ELF_EXEC_PAGESIZE > PAGE_SIZE 55 #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE 56 #else 57 #define ELF_MIN_ALIGN PAGE_SIZE 58 #endif 59 60 #ifndef ELF_CORE_EFLAGS 61 #define ELF_CORE_EFLAGS 0 62 #endif 63 64 #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1)) 65 #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1)) 66 #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1)) 67 68 static struct linux_binfmt elf_format = { 69 .module = THIS_MODULE, 70 .load_binary = load_elf_binary, 71 .load_shlib = load_elf_library, 72 .core_dump = elf_core_dump, 73 .min_coredump = ELF_EXEC_PAGESIZE, 74 }; 75 76 #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE) 77 78 static int set_brk(unsigned long start, unsigned long end) 79 { 80 start = ELF_PAGEALIGN(start); 81 end = ELF_PAGEALIGN(end); 82 if (end > start) { 83 unsigned long addr; 84 down_write(¤t->mm->mmap_sem); 85 addr = do_brk(start, end - start); 86 up_write(¤t->mm->mmap_sem); 87 if (BAD_ADDR(addr)) 88 return addr; 89 } 90 current->mm->start_brk = current->mm->brk = end; 91 return 0; 92 } 93 94 /* We need to explicitly zero any fractional pages 95 after the data section (i.e. bss). This would 96 contain the junk from the file that should not 97 be in memory 98 */ 99 static int padzero(unsigned long elf_bss) 100 { 101 unsigned long nbyte; 102 103 nbyte = ELF_PAGEOFFSET(elf_bss); 104 if (nbyte) { 105 nbyte = ELF_MIN_ALIGN - nbyte; 106 if (clear_user((void __user *) elf_bss, nbyte)) 107 return -EFAULT; 108 } 109 return 0; 110 } 111 112 /* Let's use some macros to make this stack manipulation a little clearer */ 113 #ifdef CONFIG_STACK_GROWSUP 114 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items)) 115 #define STACK_ROUND(sp, items) \ 116 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL) 117 #define STACK_ALLOC(sp, len) ({ \ 118 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \ 119 old_sp; }) 120 #else 121 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items)) 122 #define STACK_ROUND(sp, items) \ 123 (((unsigned long) (sp - items)) &~ 15UL) 124 #define STACK_ALLOC(sp, len) ({ sp -= len ; sp; }) 125 #endif 126 127 #ifndef ELF_BASE_PLATFORM 128 /* 129 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture. 130 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value 131 * will be copied to the user stack in the same manner as AT_PLATFORM. 132 */ 133 #define ELF_BASE_PLATFORM NULL 134 #endif 135 136 static int 137 create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec, 138 unsigned long load_addr, unsigned long interp_load_addr) 139 { 140 unsigned long p = bprm->p; 141 int argc = bprm->argc; 142 int envc = bprm->envc; 143 elf_addr_t __user *argv; 144 elf_addr_t __user *envp; 145 elf_addr_t __user *sp; 146 elf_addr_t __user *u_platform; 147 elf_addr_t __user *u_base_platform; 148 elf_addr_t __user *u_rand_bytes; 149 const char *k_platform = ELF_PLATFORM; 150 const char *k_base_platform = ELF_BASE_PLATFORM; 151 unsigned char k_rand_bytes[16]; 152 int items; 153 elf_addr_t *elf_info; 154 int ei_index = 0; 155 const struct cred *cred = current_cred(); 156 struct vm_area_struct *vma; 157 158 /* 159 * In some cases (e.g. Hyper-Threading), we want to avoid L1 160 * evictions by the processes running on the same package. One 161 * thing we can do is to shuffle the initial stack for them. 162 */ 163 164 p = arch_align_stack(p); 165 166 /* 167 * If this architecture has a platform capability string, copy it 168 * to userspace. In some cases (Sparc), this info is impossible 169 * for userspace to get any other way, in others (i386) it is 170 * merely difficult. 171 */ 172 u_platform = NULL; 173 if (k_platform) { 174 size_t len = strlen(k_platform) + 1; 175 176 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); 177 if (__copy_to_user(u_platform, k_platform, len)) 178 return -EFAULT; 179 } 180 181 /* 182 * If this architecture has a "base" platform capability 183 * string, copy it to userspace. 184 */ 185 u_base_platform = NULL; 186 if (k_base_platform) { 187 size_t len = strlen(k_base_platform) + 1; 188 189 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); 190 if (__copy_to_user(u_base_platform, k_base_platform, len)) 191 return -EFAULT; 192 } 193 194 /* 195 * Generate 16 random bytes for userspace PRNG seeding. 196 */ 197 get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes)); 198 u_rand_bytes = (elf_addr_t __user *) 199 STACK_ALLOC(p, sizeof(k_rand_bytes)); 200 if (__copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes))) 201 return -EFAULT; 202 203 /* Create the ELF interpreter info */ 204 elf_info = (elf_addr_t *)current->mm->saved_auxv; 205 /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */ 206 #define NEW_AUX_ENT(id, val) \ 207 do { \ 208 elf_info[ei_index++] = id; \ 209 elf_info[ei_index++] = val; \ 210 } while (0) 211 212 #ifdef ARCH_DLINFO 213 /* 214 * ARCH_DLINFO must come first so PPC can do its special alignment of 215 * AUXV. 216 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in 217 * ARCH_DLINFO changes 218 */ 219 ARCH_DLINFO; 220 #endif 221 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP); 222 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE); 223 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC); 224 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff); 225 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); 226 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum); 227 NEW_AUX_ENT(AT_BASE, interp_load_addr); 228 NEW_AUX_ENT(AT_FLAGS, 0); 229 NEW_AUX_ENT(AT_ENTRY, exec->e_entry); 230 NEW_AUX_ENT(AT_UID, cred->uid); 231 NEW_AUX_ENT(AT_EUID, cred->euid); 232 NEW_AUX_ENT(AT_GID, cred->gid); 233 NEW_AUX_ENT(AT_EGID, cred->egid); 234 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm)); 235 NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes); 236 NEW_AUX_ENT(AT_EXECFN, bprm->exec); 237 if (k_platform) { 238 NEW_AUX_ENT(AT_PLATFORM, 239 (elf_addr_t)(unsigned long)u_platform); 240 } 241 if (k_base_platform) { 242 NEW_AUX_ENT(AT_BASE_PLATFORM, 243 (elf_addr_t)(unsigned long)u_base_platform); 244 } 245 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) { 246 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data); 247 } 248 #undef NEW_AUX_ENT 249 /* AT_NULL is zero; clear the rest too */ 250 memset(&elf_info[ei_index], 0, 251 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]); 252 253 /* And advance past the AT_NULL entry. */ 254 ei_index += 2; 255 256 sp = STACK_ADD(p, ei_index); 257 258 items = (argc + 1) + (envc + 1) + 1; 259 bprm->p = STACK_ROUND(sp, items); 260 261 /* Point sp at the lowest address on the stack */ 262 #ifdef CONFIG_STACK_GROWSUP 263 sp = (elf_addr_t __user *)bprm->p - items - ei_index; 264 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */ 265 #else 266 sp = (elf_addr_t __user *)bprm->p; 267 #endif 268 269 270 /* 271 * Grow the stack manually; some architectures have a limit on how 272 * far ahead a user-space access may be in order to grow the stack. 273 */ 274 vma = find_extend_vma(current->mm, bprm->p); 275 if (!vma) 276 return -EFAULT; 277 278 /* Now, let's put argc (and argv, envp if appropriate) on the stack */ 279 if (__put_user(argc, sp++)) 280 return -EFAULT; 281 argv = sp; 282 envp = argv + argc + 1; 283 284 /* Populate argv and envp */ 285 p = current->mm->arg_end = current->mm->arg_start; 286 while (argc-- > 0) { 287 size_t len; 288 if (__put_user((elf_addr_t)p, argv++)) 289 return -EFAULT; 290 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); 291 if (!len || len > MAX_ARG_STRLEN) 292 return -EINVAL; 293 p += len; 294 } 295 if (__put_user(0, argv)) 296 return -EFAULT; 297 current->mm->arg_end = current->mm->env_start = p; 298 while (envc-- > 0) { 299 size_t len; 300 if (__put_user((elf_addr_t)p, envp++)) 301 return -EFAULT; 302 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); 303 if (!len || len > MAX_ARG_STRLEN) 304 return -EINVAL; 305 p += len; 306 } 307 if (__put_user(0, envp)) 308 return -EFAULT; 309 current->mm->env_end = p; 310 311 /* Put the elf_info on the stack in the right place. */ 312 sp = (elf_addr_t __user *)envp + 1; 313 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t))) 314 return -EFAULT; 315 return 0; 316 } 317 318 static unsigned long elf_map(struct file *filep, unsigned long addr, 319 struct elf_phdr *eppnt, int prot, int type, 320 unsigned long total_size) 321 { 322 unsigned long map_addr; 323 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr); 324 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr); 325 addr = ELF_PAGESTART(addr); 326 size = ELF_PAGEALIGN(size); 327 328 /* mmap() will return -EINVAL if given a zero size, but a 329 * segment with zero filesize is perfectly valid */ 330 if (!size) 331 return addr; 332 333 down_write(¤t->mm->mmap_sem); 334 /* 335 * total_size is the size of the ELF (interpreter) image. 336 * The _first_ mmap needs to know the full size, otherwise 337 * randomization might put this image into an overlapping 338 * position with the ELF binary image. (since size < total_size) 339 * So we first map the 'big' image - and unmap the remainder at 340 * the end. (which unmap is needed for ELF images with holes.) 341 */ 342 if (total_size) { 343 total_size = ELF_PAGEALIGN(total_size); 344 map_addr = do_mmap(filep, addr, total_size, prot, type, off); 345 if (!BAD_ADDR(map_addr)) 346 do_munmap(current->mm, map_addr+size, total_size-size); 347 } else 348 map_addr = do_mmap(filep, addr, size, prot, type, off); 349 350 up_write(¤t->mm->mmap_sem); 351 return(map_addr); 352 } 353 354 static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr) 355 { 356 int i, first_idx = -1, last_idx = -1; 357 358 for (i = 0; i < nr; i++) { 359 if (cmds[i].p_type == PT_LOAD) { 360 last_idx = i; 361 if (first_idx == -1) 362 first_idx = i; 363 } 364 } 365 if (first_idx == -1) 366 return 0; 367 368 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz - 369 ELF_PAGESTART(cmds[first_idx].p_vaddr); 370 } 371 372 373 /* This is much more generalized than the library routine read function, 374 so we keep this separate. Technically the library read function 375 is only provided so that we can read a.out libraries that have 376 an ELF header */ 377 378 static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex, 379 struct file *interpreter, unsigned long *interp_map_addr, 380 unsigned long no_base) 381 { 382 struct elf_phdr *elf_phdata; 383 struct elf_phdr *eppnt; 384 unsigned long load_addr = 0; 385 int load_addr_set = 0; 386 unsigned long last_bss = 0, elf_bss = 0; 387 unsigned long error = ~0UL; 388 unsigned long total_size; 389 int retval, i, size; 390 391 /* First of all, some simple consistency checks */ 392 if (interp_elf_ex->e_type != ET_EXEC && 393 interp_elf_ex->e_type != ET_DYN) 394 goto out; 395 if (!elf_check_arch(interp_elf_ex)) 396 goto out; 397 if (!interpreter->f_op || !interpreter->f_op->mmap) 398 goto out; 399 400 /* 401 * If the size of this structure has changed, then punt, since 402 * we will be doing the wrong thing. 403 */ 404 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr)) 405 goto out; 406 if (interp_elf_ex->e_phnum < 1 || 407 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr)) 408 goto out; 409 410 /* Now read in all of the header information */ 411 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum; 412 if (size > ELF_MIN_ALIGN) 413 goto out; 414 elf_phdata = kmalloc(size, GFP_KERNEL); 415 if (!elf_phdata) 416 goto out; 417 418 retval = kernel_read(interpreter, interp_elf_ex->e_phoff, 419 (char *)elf_phdata, size); 420 error = -EIO; 421 if (retval != size) { 422 if (retval < 0) 423 error = retval; 424 goto out_close; 425 } 426 427 total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum); 428 if (!total_size) { 429 error = -EINVAL; 430 goto out_close; 431 } 432 433 eppnt = elf_phdata; 434 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) { 435 if (eppnt->p_type == PT_LOAD) { 436 int elf_type = MAP_PRIVATE | MAP_DENYWRITE; 437 int elf_prot = 0; 438 unsigned long vaddr = 0; 439 unsigned long k, map_addr; 440 441 if (eppnt->p_flags & PF_R) 442 elf_prot = PROT_READ; 443 if (eppnt->p_flags & PF_W) 444 elf_prot |= PROT_WRITE; 445 if (eppnt->p_flags & PF_X) 446 elf_prot |= PROT_EXEC; 447 vaddr = eppnt->p_vaddr; 448 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set) 449 elf_type |= MAP_FIXED; 450 else if (no_base && interp_elf_ex->e_type == ET_DYN) 451 load_addr = -vaddr; 452 453 map_addr = elf_map(interpreter, load_addr + vaddr, 454 eppnt, elf_prot, elf_type, total_size); 455 total_size = 0; 456 if (!*interp_map_addr) 457 *interp_map_addr = map_addr; 458 error = map_addr; 459 if (BAD_ADDR(map_addr)) 460 goto out_close; 461 462 if (!load_addr_set && 463 interp_elf_ex->e_type == ET_DYN) { 464 load_addr = map_addr - ELF_PAGESTART(vaddr); 465 load_addr_set = 1; 466 } 467 468 /* 469 * Check to see if the section's size will overflow the 470 * allowed task size. Note that p_filesz must always be 471 * <= p_memsize so it's only necessary to check p_memsz. 472 */ 473 k = load_addr + eppnt->p_vaddr; 474 if (BAD_ADDR(k) || 475 eppnt->p_filesz > eppnt->p_memsz || 476 eppnt->p_memsz > TASK_SIZE || 477 TASK_SIZE - eppnt->p_memsz < k) { 478 error = -ENOMEM; 479 goto out_close; 480 } 481 482 /* 483 * Find the end of the file mapping for this phdr, and 484 * keep track of the largest address we see for this. 485 */ 486 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz; 487 if (k > elf_bss) 488 elf_bss = k; 489 490 /* 491 * Do the same thing for the memory mapping - between 492 * elf_bss and last_bss is the bss section. 493 */ 494 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr; 495 if (k > last_bss) 496 last_bss = k; 497 } 498 } 499 500 if (last_bss > elf_bss) { 501 /* 502 * Now fill out the bss section. First pad the last page up 503 * to the page boundary, and then perform a mmap to make sure 504 * that there are zero-mapped pages up to and including the 505 * last bss page. 506 */ 507 if (padzero(elf_bss)) { 508 error = -EFAULT; 509 goto out_close; 510 } 511 512 /* What we have mapped so far */ 513 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1); 514 515 /* Map the last of the bss segment */ 516 down_write(¤t->mm->mmap_sem); 517 error = do_brk(elf_bss, last_bss - elf_bss); 518 up_write(¤t->mm->mmap_sem); 519 if (BAD_ADDR(error)) 520 goto out_close; 521 } 522 523 error = load_addr; 524 525 out_close: 526 kfree(elf_phdata); 527 out: 528 return error; 529 } 530 531 /* 532 * These are the functions used to load ELF style executables and shared 533 * libraries. There is no binary dependent code anywhere else. 534 */ 535 536 #define INTERPRETER_NONE 0 537 #define INTERPRETER_ELF 2 538 539 #ifndef STACK_RND_MASK 540 #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */ 541 #endif 542 543 static unsigned long randomize_stack_top(unsigned long stack_top) 544 { 545 unsigned int random_variable = 0; 546 547 if ((current->flags & PF_RANDOMIZE) && 548 !(current->personality & ADDR_NO_RANDOMIZE)) { 549 random_variable = get_random_int() & STACK_RND_MASK; 550 random_variable <<= PAGE_SHIFT; 551 } 552 #ifdef CONFIG_STACK_GROWSUP 553 return PAGE_ALIGN(stack_top) + random_variable; 554 #else 555 return PAGE_ALIGN(stack_top) - random_variable; 556 #endif 557 } 558 559 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) 560 { 561 struct file *interpreter = NULL; /* to shut gcc up */ 562 unsigned long load_addr = 0, load_bias = 0; 563 int load_addr_set = 0; 564 char * elf_interpreter = NULL; 565 unsigned long error; 566 struct elf_phdr *elf_ppnt, *elf_phdata; 567 unsigned long elf_bss, elf_brk; 568 int retval, i; 569 unsigned int size; 570 unsigned long elf_entry; 571 unsigned long interp_load_addr = 0; 572 unsigned long start_code, end_code, start_data, end_data; 573 unsigned long reloc_func_desc = 0; 574 int executable_stack = EXSTACK_DEFAULT; 575 unsigned long def_flags = 0; 576 struct { 577 struct elfhdr elf_ex; 578 struct elfhdr interp_elf_ex; 579 } *loc; 580 581 loc = kmalloc(sizeof(*loc), GFP_KERNEL); 582 if (!loc) { 583 retval = -ENOMEM; 584 goto out_ret; 585 } 586 587 /* Get the exec-header */ 588 loc->elf_ex = *((struct elfhdr *)bprm->buf); 589 590 retval = -ENOEXEC; 591 /* First of all, some simple consistency checks */ 592 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0) 593 goto out; 594 595 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN) 596 goto out; 597 if (!elf_check_arch(&loc->elf_ex)) 598 goto out; 599 if (!bprm->file->f_op || !bprm->file->f_op->mmap) 600 goto out; 601 602 /* Now read in all of the header information */ 603 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr)) 604 goto out; 605 if (loc->elf_ex.e_phnum < 1 || 606 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr)) 607 goto out; 608 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr); 609 retval = -ENOMEM; 610 elf_phdata = kmalloc(size, GFP_KERNEL); 611 if (!elf_phdata) 612 goto out; 613 614 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff, 615 (char *)elf_phdata, size); 616 if (retval != size) { 617 if (retval >= 0) 618 retval = -EIO; 619 goto out_free_ph; 620 } 621 622 elf_ppnt = elf_phdata; 623 elf_bss = 0; 624 elf_brk = 0; 625 626 start_code = ~0UL; 627 end_code = 0; 628 start_data = 0; 629 end_data = 0; 630 631 for (i = 0; i < loc->elf_ex.e_phnum; i++) { 632 if (elf_ppnt->p_type == PT_INTERP) { 633 /* This is the program interpreter used for 634 * shared libraries - for now assume that this 635 * is an a.out format binary 636 */ 637 retval = -ENOEXEC; 638 if (elf_ppnt->p_filesz > PATH_MAX || 639 elf_ppnt->p_filesz < 2) 640 goto out_free_ph; 641 642 retval = -ENOMEM; 643 elf_interpreter = kmalloc(elf_ppnt->p_filesz, 644 GFP_KERNEL); 645 if (!elf_interpreter) 646 goto out_free_ph; 647 648 retval = kernel_read(bprm->file, elf_ppnt->p_offset, 649 elf_interpreter, 650 elf_ppnt->p_filesz); 651 if (retval != elf_ppnt->p_filesz) { 652 if (retval >= 0) 653 retval = -EIO; 654 goto out_free_interp; 655 } 656 /* make sure path is NULL terminated */ 657 retval = -ENOEXEC; 658 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0') 659 goto out_free_interp; 660 661 interpreter = open_exec(elf_interpreter); 662 retval = PTR_ERR(interpreter); 663 if (IS_ERR(interpreter)) 664 goto out_free_interp; 665 666 /* 667 * If the binary is not readable then enforce 668 * mm->dumpable = 0 regardless of the interpreter's 669 * permissions. 670 */ 671 if (file_permission(interpreter, MAY_READ) < 0) 672 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP; 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->flags &= ~PF_FORKNOEXEC; 717 current->mm->def_flags = def_flags; 718 719 /* Do this immediately, since STACK_TOP as used in setup_arg_pages 720 may depend on the personality. */ 721 SET_PERSONALITY(loc->elf_ex); 722 if (elf_read_implies_exec(loc->elf_ex, executable_stack)) 723 current->personality |= READ_IMPLIES_EXEC; 724 725 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) 726 current->flags |= PF_RANDOMIZE; 727 728 setup_new_exec(bprm); 729 730 /* Do this so that we can load the interpreter, if need be. We will 731 change some of these later */ 732 current->mm->free_area_cache = current->mm->mmap_base; 733 current->mm->cached_hole_size = 0; 734 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP), 735 executable_stack); 736 if (retval < 0) { 737 send_sig(SIGKILL, current, 0); 738 goto out_free_dentry; 739 } 740 741 current->mm->start_stack = bprm->p; 742 743 /* Now we do a little grungy work by mmapping the ELF image into 744 the correct location in memory. */ 745 for(i = 0, elf_ppnt = elf_phdata; 746 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) { 747 int elf_prot = 0, elf_flags; 748 unsigned long k, vaddr; 749 750 if (elf_ppnt->p_type != PT_LOAD) 751 continue; 752 753 if (unlikely (elf_brk > elf_bss)) { 754 unsigned long nbyte; 755 756 /* There was a PT_LOAD segment with p_memsz > p_filesz 757 before this one. Map anonymous pages, if needed, 758 and clear the area. */ 759 retval = set_brk(elf_bss + load_bias, 760 elf_brk + load_bias); 761 if (retval) { 762 send_sig(SIGKILL, current, 0); 763 goto out_free_dentry; 764 } 765 nbyte = ELF_PAGEOFFSET(elf_bss); 766 if (nbyte) { 767 nbyte = ELF_MIN_ALIGN - nbyte; 768 if (nbyte > elf_brk - elf_bss) 769 nbyte = elf_brk - elf_bss; 770 if (clear_user((void __user *)elf_bss + 771 load_bias, nbyte)) { 772 /* 773 * This bss-zeroing can fail if the ELF 774 * file specifies odd protections. So 775 * we don't check the return value 776 */ 777 } 778 } 779 } 780 781 if (elf_ppnt->p_flags & PF_R) 782 elf_prot |= PROT_READ; 783 if (elf_ppnt->p_flags & PF_W) 784 elf_prot |= PROT_WRITE; 785 if (elf_ppnt->p_flags & PF_X) 786 elf_prot |= PROT_EXEC; 787 788 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE; 789 790 vaddr = elf_ppnt->p_vaddr; 791 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) { 792 elf_flags |= MAP_FIXED; 793 } else if (loc->elf_ex.e_type == ET_DYN) { 794 /* Try and get dynamic programs out of the way of the 795 * default mmap base, as well as whatever program they 796 * might try to exec. This is because the brk will 797 * follow the loader, and is not movable. */ 798 #if defined(CONFIG_X86) || defined(CONFIG_ARM) 799 load_bias = 0; 800 #else 801 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr); 802 #endif 803 } 804 805 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt, 806 elf_prot, elf_flags, 0); 807 if (BAD_ADDR(error)) { 808 send_sig(SIGKILL, current, 0); 809 retval = IS_ERR((void *)error) ? 810 PTR_ERR((void*)error) : -EINVAL; 811 goto out_free_dentry; 812 } 813 814 if (!load_addr_set) { 815 load_addr_set = 1; 816 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset); 817 if (loc->elf_ex.e_type == ET_DYN) { 818 load_bias += error - 819 ELF_PAGESTART(load_bias + vaddr); 820 load_addr += load_bias; 821 reloc_func_desc = load_bias; 822 } 823 } 824 k = elf_ppnt->p_vaddr; 825 if (k < start_code) 826 start_code = k; 827 if (start_data < k) 828 start_data = k; 829 830 /* 831 * Check to see if the section's size will overflow the 832 * allowed task size. Note that p_filesz must always be 833 * <= p_memsz so it is only necessary to check p_memsz. 834 */ 835 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz || 836 elf_ppnt->p_memsz > TASK_SIZE || 837 TASK_SIZE - elf_ppnt->p_memsz < k) { 838 /* set_brk can never work. Avoid overflows. */ 839 send_sig(SIGKILL, current, 0); 840 retval = -EINVAL; 841 goto out_free_dentry; 842 } 843 844 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz; 845 846 if (k > elf_bss) 847 elf_bss = k; 848 if ((elf_ppnt->p_flags & PF_X) && end_code < k) 849 end_code = k; 850 if (end_data < k) 851 end_data = k; 852 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz; 853 if (k > elf_brk) 854 elf_brk = k; 855 } 856 857 loc->elf_ex.e_entry += load_bias; 858 elf_bss += load_bias; 859 elf_brk += load_bias; 860 start_code += load_bias; 861 end_code += load_bias; 862 start_data += load_bias; 863 end_data += load_bias; 864 865 /* Calling set_brk effectively mmaps the pages that we need 866 * for the bss and break sections. We must do this before 867 * mapping in the interpreter, to make sure it doesn't wind 868 * up getting placed where the bss needs to go. 869 */ 870 retval = set_brk(elf_bss, elf_brk); 871 if (retval) { 872 send_sig(SIGKILL, current, 0); 873 goto out_free_dentry; 874 } 875 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) { 876 send_sig(SIGSEGV, current, 0); 877 retval = -EFAULT; /* Nobody gets to see this, but.. */ 878 goto out_free_dentry; 879 } 880 881 if (elf_interpreter) { 882 unsigned long uninitialized_var(interp_map_addr); 883 884 elf_entry = load_elf_interp(&loc->interp_elf_ex, 885 interpreter, 886 &interp_map_addr, 887 load_bias); 888 if (!IS_ERR((void *)elf_entry)) { 889 /* 890 * load_elf_interp() returns relocation 891 * adjustment 892 */ 893 interp_load_addr = elf_entry; 894 elf_entry += loc->interp_elf_ex.e_entry; 895 } 896 if (BAD_ADDR(elf_entry)) { 897 force_sig(SIGSEGV, current); 898 retval = IS_ERR((void *)elf_entry) ? 899 (int)elf_entry : -EINVAL; 900 goto out_free_dentry; 901 } 902 reloc_func_desc = interp_load_addr; 903 904 allow_write_access(interpreter); 905 fput(interpreter); 906 kfree(elf_interpreter); 907 } else { 908 elf_entry = loc->elf_ex.e_entry; 909 if (BAD_ADDR(elf_entry)) { 910 force_sig(SIGSEGV, current); 911 retval = -EINVAL; 912 goto out_free_dentry; 913 } 914 } 915 916 kfree(elf_phdata); 917 918 set_binfmt(&elf_format); 919 920 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES 921 retval = arch_setup_additional_pages(bprm, !!elf_interpreter); 922 if (retval < 0) { 923 send_sig(SIGKILL, current, 0); 924 goto out; 925 } 926 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */ 927 928 install_exec_creds(bprm); 929 current->flags &= ~PF_FORKNOEXEC; 930 retval = create_elf_tables(bprm, &loc->elf_ex, 931 load_addr, interp_load_addr); 932 if (retval < 0) { 933 send_sig(SIGKILL, current, 0); 934 goto out; 935 } 936 /* N.B. passed_fileno might not be initialized? */ 937 current->mm->end_code = end_code; 938 current->mm->start_code = start_code; 939 current->mm->start_data = start_data; 940 current->mm->end_data = end_data; 941 current->mm->start_stack = bprm->p; 942 943 #ifdef arch_randomize_brk 944 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) 945 current->mm->brk = current->mm->start_brk = 946 arch_randomize_brk(current->mm); 947 #endif 948 949 if (current->personality & MMAP_PAGE_ZERO) { 950 /* Why this, you ask??? Well SVr4 maps page 0 as read-only, 951 and some applications "depend" upon this behavior. 952 Since we do not have the power to recompile these, we 953 emulate the SVr4 behavior. Sigh. */ 954 down_write(¤t->mm->mmap_sem); 955 error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC, 956 MAP_FIXED | MAP_PRIVATE, 0); 957 up_write(¤t->mm->mmap_sem); 958 } 959 960 #ifdef ELF_PLAT_INIT 961 /* 962 * The ABI may specify that certain registers be set up in special 963 * ways (on i386 %edx is the address of a DT_FINI function, for 964 * example. In addition, it may also specify (eg, PowerPC64 ELF) 965 * that the e_entry field is the address of the function descriptor 966 * for the startup routine, rather than the address of the startup 967 * routine itself. This macro performs whatever initialization to 968 * the regs structure is required as well as any relocations to the 969 * function descriptor entries when executing dynamically links apps. 970 */ 971 ELF_PLAT_INIT(regs, reloc_func_desc); 972 #endif 973 974 start_thread(regs, elf_entry, bprm->p); 975 retval = 0; 976 out: 977 kfree(loc); 978 out_ret: 979 return retval; 980 981 /* error cleanup */ 982 out_free_dentry: 983 allow_write_access(interpreter); 984 if (interpreter) 985 fput(interpreter); 986 out_free_interp: 987 kfree(elf_interpreter); 988 out_free_ph: 989 kfree(elf_phdata); 990 goto out; 991 } 992 993 /* This is really simpleminded and specialized - we are loading an 994 a.out library that is given an ELF header. */ 995 static int load_elf_library(struct file *file) 996 { 997 struct elf_phdr *elf_phdata; 998 struct elf_phdr *eppnt; 999 unsigned long elf_bss, bss, len; 1000 int retval, error, i, j; 1001 struct elfhdr elf_ex; 1002 1003 error = -ENOEXEC; 1004 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex)); 1005 if (retval != sizeof(elf_ex)) 1006 goto out; 1007 1008 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0) 1009 goto out; 1010 1011 /* First of all, some simple consistency checks */ 1012 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 || 1013 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap) 1014 goto out; 1015 1016 /* Now read in all of the header information */ 1017 1018 j = sizeof(struct elf_phdr) * elf_ex.e_phnum; 1019 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */ 1020 1021 error = -ENOMEM; 1022 elf_phdata = kmalloc(j, GFP_KERNEL); 1023 if (!elf_phdata) 1024 goto out; 1025 1026 eppnt = elf_phdata; 1027 error = -ENOEXEC; 1028 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j); 1029 if (retval != j) 1030 goto out_free_ph; 1031 1032 for (j = 0, i = 0; i<elf_ex.e_phnum; i++) 1033 if ((eppnt + i)->p_type == PT_LOAD) 1034 j++; 1035 if (j != 1) 1036 goto out_free_ph; 1037 1038 while (eppnt->p_type != PT_LOAD) 1039 eppnt++; 1040 1041 /* Now use mmap to map the library into memory. */ 1042 down_write(¤t->mm->mmap_sem); 1043 error = do_mmap(file, 1044 ELF_PAGESTART(eppnt->p_vaddr), 1045 (eppnt->p_filesz + 1046 ELF_PAGEOFFSET(eppnt->p_vaddr)), 1047 PROT_READ | PROT_WRITE | PROT_EXEC, 1048 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, 1049 (eppnt->p_offset - 1050 ELF_PAGEOFFSET(eppnt->p_vaddr))); 1051 up_write(¤t->mm->mmap_sem); 1052 if (error != ELF_PAGESTART(eppnt->p_vaddr)) 1053 goto out_free_ph; 1054 1055 elf_bss = eppnt->p_vaddr + eppnt->p_filesz; 1056 if (padzero(elf_bss)) { 1057 error = -EFAULT; 1058 goto out_free_ph; 1059 } 1060 1061 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr + 1062 ELF_MIN_ALIGN - 1); 1063 bss = eppnt->p_memsz + eppnt->p_vaddr; 1064 if (bss > len) { 1065 down_write(¤t->mm->mmap_sem); 1066 do_brk(len, bss - len); 1067 up_write(¤t->mm->mmap_sem); 1068 } 1069 error = 0; 1070 1071 out_free_ph: 1072 kfree(elf_phdata); 1073 out: 1074 return error; 1075 } 1076 1077 #ifdef CONFIG_ELF_CORE 1078 /* 1079 * ELF core dumper 1080 * 1081 * Modelled on fs/exec.c:aout_core_dump() 1082 * Jeremy Fitzhardinge <jeremy@sw.oz.au> 1083 */ 1084 1085 /* 1086 * Decide what to dump of a segment, part, all or none. 1087 */ 1088 static unsigned long vma_dump_size(struct vm_area_struct *vma, 1089 unsigned long mm_flags) 1090 { 1091 #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type)) 1092 1093 /* The vma can be set up to tell us the answer directly. */ 1094 if (vma->vm_flags & VM_ALWAYSDUMP) 1095 goto whole; 1096 1097 /* Hugetlb memory check */ 1098 if (vma->vm_flags & VM_HUGETLB) { 1099 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED)) 1100 goto whole; 1101 if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE)) 1102 goto whole; 1103 } 1104 1105 /* Do not dump I/O mapped devices or special mappings */ 1106 if (vma->vm_flags & (VM_IO | VM_RESERVED)) 1107 return 0; 1108 1109 /* By default, dump shared memory if mapped from an anonymous file. */ 1110 if (vma->vm_flags & VM_SHARED) { 1111 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ? 1112 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED)) 1113 goto whole; 1114 return 0; 1115 } 1116 1117 /* Dump segments that have been written to. */ 1118 if (vma->anon_vma && FILTER(ANON_PRIVATE)) 1119 goto whole; 1120 if (vma->vm_file == NULL) 1121 return 0; 1122 1123 if (FILTER(MAPPED_PRIVATE)) 1124 goto whole; 1125 1126 /* 1127 * If this looks like the beginning of a DSO or executable mapping, 1128 * check for an ELF header. If we find one, dump the first page to 1129 * aid in determining what was mapped here. 1130 */ 1131 if (FILTER(ELF_HEADERS) && 1132 vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) { 1133 u32 __user *header = (u32 __user *) vma->vm_start; 1134 u32 word; 1135 mm_segment_t fs = get_fs(); 1136 /* 1137 * Doing it this way gets the constant folded by GCC. 1138 */ 1139 union { 1140 u32 cmp; 1141 char elfmag[SELFMAG]; 1142 } magic; 1143 BUILD_BUG_ON(SELFMAG != sizeof word); 1144 magic.elfmag[EI_MAG0] = ELFMAG0; 1145 magic.elfmag[EI_MAG1] = ELFMAG1; 1146 magic.elfmag[EI_MAG2] = ELFMAG2; 1147 magic.elfmag[EI_MAG3] = ELFMAG3; 1148 /* 1149 * Switch to the user "segment" for get_user(), 1150 * then put back what elf_core_dump() had in place. 1151 */ 1152 set_fs(USER_DS); 1153 if (unlikely(get_user(word, header))) 1154 word = 0; 1155 set_fs(fs); 1156 if (word == magic.cmp) 1157 return PAGE_SIZE; 1158 } 1159 1160 #undef FILTER 1161 1162 return 0; 1163 1164 whole: 1165 return vma->vm_end - vma->vm_start; 1166 } 1167 1168 /* An ELF note in memory */ 1169 struct memelfnote 1170 { 1171 const char *name; 1172 int type; 1173 unsigned int datasz; 1174 void *data; 1175 }; 1176 1177 static int notesize(struct memelfnote *en) 1178 { 1179 int sz; 1180 1181 sz = sizeof(struct elf_note); 1182 sz += roundup(strlen(en->name) + 1, 4); 1183 sz += roundup(en->datasz, 4); 1184 1185 return sz; 1186 } 1187 1188 #define DUMP_WRITE(addr, nr, foffset) \ 1189 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0) 1190 1191 static int alignfile(struct file *file, loff_t *foffset) 1192 { 1193 static const char buf[4] = { 0, }; 1194 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset); 1195 return 1; 1196 } 1197 1198 static int writenote(struct memelfnote *men, struct file *file, 1199 loff_t *foffset) 1200 { 1201 struct elf_note en; 1202 en.n_namesz = strlen(men->name) + 1; 1203 en.n_descsz = men->datasz; 1204 en.n_type = men->type; 1205 1206 DUMP_WRITE(&en, sizeof(en), foffset); 1207 DUMP_WRITE(men->name, en.n_namesz, foffset); 1208 if (!alignfile(file, foffset)) 1209 return 0; 1210 DUMP_WRITE(men->data, men->datasz, foffset); 1211 if (!alignfile(file, foffset)) 1212 return 0; 1213 1214 return 1; 1215 } 1216 #undef DUMP_WRITE 1217 1218 static void fill_elf_header(struct elfhdr *elf, int segs, 1219 u16 machine, u32 flags, u8 osabi) 1220 { 1221 memset(elf, 0, sizeof(*elf)); 1222 1223 memcpy(elf->e_ident, ELFMAG, SELFMAG); 1224 elf->e_ident[EI_CLASS] = ELF_CLASS; 1225 elf->e_ident[EI_DATA] = ELF_DATA; 1226 elf->e_ident[EI_VERSION] = EV_CURRENT; 1227 elf->e_ident[EI_OSABI] = ELF_OSABI; 1228 1229 elf->e_type = ET_CORE; 1230 elf->e_machine = machine; 1231 elf->e_version = EV_CURRENT; 1232 elf->e_phoff = sizeof(struct elfhdr); 1233 elf->e_flags = flags; 1234 elf->e_ehsize = sizeof(struct elfhdr); 1235 elf->e_phentsize = sizeof(struct elf_phdr); 1236 elf->e_phnum = segs; 1237 1238 return; 1239 } 1240 1241 static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset) 1242 { 1243 phdr->p_type = PT_NOTE; 1244 phdr->p_offset = offset; 1245 phdr->p_vaddr = 0; 1246 phdr->p_paddr = 0; 1247 phdr->p_filesz = sz; 1248 phdr->p_memsz = 0; 1249 phdr->p_flags = 0; 1250 phdr->p_align = 0; 1251 return; 1252 } 1253 1254 static void fill_note(struct memelfnote *note, const char *name, int type, 1255 unsigned int sz, void *data) 1256 { 1257 note->name = name; 1258 note->type = type; 1259 note->datasz = sz; 1260 note->data = data; 1261 return; 1262 } 1263 1264 /* 1265 * fill up all the fields in prstatus from the given task struct, except 1266 * registers which need to be filled up separately. 1267 */ 1268 static void fill_prstatus(struct elf_prstatus *prstatus, 1269 struct task_struct *p, long signr) 1270 { 1271 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr; 1272 prstatus->pr_sigpend = p->pending.signal.sig[0]; 1273 prstatus->pr_sighold = p->blocked.sig[0]; 1274 rcu_read_lock(); 1275 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); 1276 rcu_read_unlock(); 1277 prstatus->pr_pid = task_pid_vnr(p); 1278 prstatus->pr_pgrp = task_pgrp_vnr(p); 1279 prstatus->pr_sid = task_session_vnr(p); 1280 if (thread_group_leader(p)) { 1281 struct task_cputime cputime; 1282 1283 /* 1284 * This is the record for the group leader. It shows the 1285 * group-wide total, not its individual thread total. 1286 */ 1287 thread_group_cputime(p, &cputime); 1288 cputime_to_timeval(cputime.utime, &prstatus->pr_utime); 1289 cputime_to_timeval(cputime.stime, &prstatus->pr_stime); 1290 } else { 1291 cputime_to_timeval(p->utime, &prstatus->pr_utime); 1292 cputime_to_timeval(p->stime, &prstatus->pr_stime); 1293 } 1294 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime); 1295 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime); 1296 } 1297 1298 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, 1299 struct mm_struct *mm) 1300 { 1301 const struct cred *cred; 1302 unsigned int i, len; 1303 1304 /* first copy the parameters from user space */ 1305 memset(psinfo, 0, sizeof(struct elf_prpsinfo)); 1306 1307 len = mm->arg_end - mm->arg_start; 1308 if (len >= ELF_PRARGSZ) 1309 len = ELF_PRARGSZ-1; 1310 if (copy_from_user(&psinfo->pr_psargs, 1311 (const char __user *)mm->arg_start, len)) 1312 return -EFAULT; 1313 for(i = 0; i < len; i++) 1314 if (psinfo->pr_psargs[i] == 0) 1315 psinfo->pr_psargs[i] = ' '; 1316 psinfo->pr_psargs[len] = 0; 1317 1318 rcu_read_lock(); 1319 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); 1320 rcu_read_unlock(); 1321 psinfo->pr_pid = task_pid_vnr(p); 1322 psinfo->pr_pgrp = task_pgrp_vnr(p); 1323 psinfo->pr_sid = task_session_vnr(p); 1324 1325 i = p->state ? ffz(~p->state) + 1 : 0; 1326 psinfo->pr_state = i; 1327 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i]; 1328 psinfo->pr_zomb = psinfo->pr_sname == 'Z'; 1329 psinfo->pr_nice = task_nice(p); 1330 psinfo->pr_flag = p->flags; 1331 rcu_read_lock(); 1332 cred = __task_cred(p); 1333 SET_UID(psinfo->pr_uid, cred->uid); 1334 SET_GID(psinfo->pr_gid, cred->gid); 1335 rcu_read_unlock(); 1336 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); 1337 1338 return 0; 1339 } 1340 1341 static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm) 1342 { 1343 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv; 1344 int i = 0; 1345 do 1346 i += 2; 1347 while (auxv[i - 2] != AT_NULL); 1348 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv); 1349 } 1350 1351 #ifdef CORE_DUMP_USE_REGSET 1352 #include <linux/regset.h> 1353 1354 struct elf_thread_core_info { 1355 struct elf_thread_core_info *next; 1356 struct task_struct *task; 1357 struct elf_prstatus prstatus; 1358 struct memelfnote notes[0]; 1359 }; 1360 1361 struct elf_note_info { 1362 struct elf_thread_core_info *thread; 1363 struct memelfnote psinfo; 1364 struct memelfnote auxv; 1365 size_t size; 1366 int thread_notes; 1367 }; 1368 1369 /* 1370 * When a regset has a writeback hook, we call it on each thread before 1371 * dumping user memory. On register window machines, this makes sure the 1372 * user memory backing the register data is up to date before we read it. 1373 */ 1374 static void do_thread_regset_writeback(struct task_struct *task, 1375 const struct user_regset *regset) 1376 { 1377 if (regset->writeback) 1378 regset->writeback(task, regset, 1); 1379 } 1380 1381 static int fill_thread_core_info(struct elf_thread_core_info *t, 1382 const struct user_regset_view *view, 1383 long signr, size_t *total) 1384 { 1385 unsigned int i; 1386 1387 /* 1388 * NT_PRSTATUS is the one special case, because the regset data 1389 * goes into the pr_reg field inside the note contents, rather 1390 * than being the whole note contents. We fill the reset in here. 1391 * We assume that regset 0 is NT_PRSTATUS. 1392 */ 1393 fill_prstatus(&t->prstatus, t->task, signr); 1394 (void) view->regsets[0].get(t->task, &view->regsets[0], 1395 0, sizeof(t->prstatus.pr_reg), 1396 &t->prstatus.pr_reg, NULL); 1397 1398 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, 1399 sizeof(t->prstatus), &t->prstatus); 1400 *total += notesize(&t->notes[0]); 1401 1402 do_thread_regset_writeback(t->task, &view->regsets[0]); 1403 1404 /* 1405 * Each other regset might generate a note too. For each regset 1406 * that has no core_note_type or is inactive, we leave t->notes[i] 1407 * all zero and we'll know to skip writing it later. 1408 */ 1409 for (i = 1; i < view->n; ++i) { 1410 const struct user_regset *regset = &view->regsets[i]; 1411 do_thread_regset_writeback(t->task, regset); 1412 if (regset->core_note_type && 1413 (!regset->active || regset->active(t->task, regset))) { 1414 int ret; 1415 size_t size = regset->n * regset->size; 1416 void *data = kmalloc(size, GFP_KERNEL); 1417 if (unlikely(!data)) 1418 return 0; 1419 ret = regset->get(t->task, regset, 1420 0, size, data, NULL); 1421 if (unlikely(ret)) 1422 kfree(data); 1423 else { 1424 if (regset->core_note_type != NT_PRFPREG) 1425 fill_note(&t->notes[i], "LINUX", 1426 regset->core_note_type, 1427 size, data); 1428 else { 1429 t->prstatus.pr_fpvalid = 1; 1430 fill_note(&t->notes[i], "CORE", 1431 NT_PRFPREG, size, data); 1432 } 1433 *total += notesize(&t->notes[i]); 1434 } 1435 } 1436 } 1437 1438 return 1; 1439 } 1440 1441 static int fill_note_info(struct elfhdr *elf, int phdrs, 1442 struct elf_note_info *info, 1443 long signr, struct pt_regs *regs) 1444 { 1445 struct task_struct *dump_task = current; 1446 const struct user_regset_view *view = task_user_regset_view(dump_task); 1447 struct elf_thread_core_info *t; 1448 struct elf_prpsinfo *psinfo; 1449 struct core_thread *ct; 1450 unsigned int i; 1451 1452 info->size = 0; 1453 info->thread = NULL; 1454 1455 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL); 1456 if (psinfo == NULL) 1457 return 0; 1458 1459 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo); 1460 1461 /* 1462 * Figure out how many notes we're going to need for each thread. 1463 */ 1464 info->thread_notes = 0; 1465 for (i = 0; i < view->n; ++i) 1466 if (view->regsets[i].core_note_type != 0) 1467 ++info->thread_notes; 1468 1469 /* 1470 * Sanity check. We rely on regset 0 being in NT_PRSTATUS, 1471 * since it is our one special case. 1472 */ 1473 if (unlikely(info->thread_notes == 0) || 1474 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) { 1475 WARN_ON(1); 1476 return 0; 1477 } 1478 1479 /* 1480 * Initialize the ELF file header. 1481 */ 1482 fill_elf_header(elf, phdrs, 1483 view->e_machine, view->e_flags, view->ei_osabi); 1484 1485 /* 1486 * Allocate a structure for each thread. 1487 */ 1488 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) { 1489 t = kzalloc(offsetof(struct elf_thread_core_info, 1490 notes[info->thread_notes]), 1491 GFP_KERNEL); 1492 if (unlikely(!t)) 1493 return 0; 1494 1495 t->task = ct->task; 1496 if (ct->task == dump_task || !info->thread) { 1497 t->next = info->thread; 1498 info->thread = t; 1499 } else { 1500 /* 1501 * Make sure to keep the original task at 1502 * the head of the list. 1503 */ 1504 t->next = info->thread->next; 1505 info->thread->next = t; 1506 } 1507 } 1508 1509 /* 1510 * Now fill in each thread's information. 1511 */ 1512 for (t = info->thread; t != NULL; t = t->next) 1513 if (!fill_thread_core_info(t, view, signr, &info->size)) 1514 return 0; 1515 1516 /* 1517 * Fill in the two process-wide notes. 1518 */ 1519 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm); 1520 info->size += notesize(&info->psinfo); 1521 1522 fill_auxv_note(&info->auxv, current->mm); 1523 info->size += notesize(&info->auxv); 1524 1525 return 1; 1526 } 1527 1528 static size_t get_note_info_size(struct elf_note_info *info) 1529 { 1530 return info->size; 1531 } 1532 1533 /* 1534 * Write all the notes for each thread. When writing the first thread, the 1535 * process-wide notes are interleaved after the first thread-specific note. 1536 */ 1537 static int write_note_info(struct elf_note_info *info, 1538 struct file *file, loff_t *foffset) 1539 { 1540 bool first = 1; 1541 struct elf_thread_core_info *t = info->thread; 1542 1543 do { 1544 int i; 1545 1546 if (!writenote(&t->notes[0], file, foffset)) 1547 return 0; 1548 1549 if (first && !writenote(&info->psinfo, file, foffset)) 1550 return 0; 1551 if (first && !writenote(&info->auxv, file, foffset)) 1552 return 0; 1553 1554 for (i = 1; i < info->thread_notes; ++i) 1555 if (t->notes[i].data && 1556 !writenote(&t->notes[i], file, foffset)) 1557 return 0; 1558 1559 first = 0; 1560 t = t->next; 1561 } while (t); 1562 1563 return 1; 1564 } 1565 1566 static void free_note_info(struct elf_note_info *info) 1567 { 1568 struct elf_thread_core_info *threads = info->thread; 1569 while (threads) { 1570 unsigned int i; 1571 struct elf_thread_core_info *t = threads; 1572 threads = t->next; 1573 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus); 1574 for (i = 1; i < info->thread_notes; ++i) 1575 kfree(t->notes[i].data); 1576 kfree(t); 1577 } 1578 kfree(info->psinfo.data); 1579 } 1580 1581 #else 1582 1583 /* Here is the structure in which status of each thread is captured. */ 1584 struct elf_thread_status 1585 { 1586 struct list_head list; 1587 struct elf_prstatus prstatus; /* NT_PRSTATUS */ 1588 elf_fpregset_t fpu; /* NT_PRFPREG */ 1589 struct task_struct *thread; 1590 #ifdef ELF_CORE_COPY_XFPREGS 1591 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */ 1592 #endif 1593 struct memelfnote notes[3]; 1594 int num_notes; 1595 }; 1596 1597 /* 1598 * In order to add the specific thread information for the elf file format, 1599 * we need to keep a linked list of every threads pr_status and then create 1600 * a single section for them in the final core file. 1601 */ 1602 static int elf_dump_thread_status(long signr, struct elf_thread_status *t) 1603 { 1604 int sz = 0; 1605 struct task_struct *p = t->thread; 1606 t->num_notes = 0; 1607 1608 fill_prstatus(&t->prstatus, p, signr); 1609 elf_core_copy_task_regs(p, &t->prstatus.pr_reg); 1610 1611 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), 1612 &(t->prstatus)); 1613 t->num_notes++; 1614 sz += notesize(&t->notes[0]); 1615 1616 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, 1617 &t->fpu))) { 1618 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), 1619 &(t->fpu)); 1620 t->num_notes++; 1621 sz += notesize(&t->notes[1]); 1622 } 1623 1624 #ifdef ELF_CORE_COPY_XFPREGS 1625 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) { 1626 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE, 1627 sizeof(t->xfpu), &t->xfpu); 1628 t->num_notes++; 1629 sz += notesize(&t->notes[2]); 1630 } 1631 #endif 1632 return sz; 1633 } 1634 1635 struct elf_note_info { 1636 struct memelfnote *notes; 1637 struct elf_prstatus *prstatus; /* NT_PRSTATUS */ 1638 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */ 1639 struct list_head thread_list; 1640 elf_fpregset_t *fpu; 1641 #ifdef ELF_CORE_COPY_XFPREGS 1642 elf_fpxregset_t *xfpu; 1643 #endif 1644 int thread_status_size; 1645 int numnote; 1646 }; 1647 1648 static int elf_note_info_init(struct elf_note_info *info) 1649 { 1650 memset(info, 0, sizeof(*info)); 1651 INIT_LIST_HEAD(&info->thread_list); 1652 1653 /* Allocate space for six ELF notes */ 1654 info->notes = kmalloc(6 * sizeof(struct memelfnote), GFP_KERNEL); 1655 if (!info->notes) 1656 return 0; 1657 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL); 1658 if (!info->psinfo) 1659 goto notes_free; 1660 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL); 1661 if (!info->prstatus) 1662 goto psinfo_free; 1663 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL); 1664 if (!info->fpu) 1665 goto prstatus_free; 1666 #ifdef ELF_CORE_COPY_XFPREGS 1667 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL); 1668 if (!info->xfpu) 1669 goto fpu_free; 1670 #endif 1671 return 1; 1672 #ifdef ELF_CORE_COPY_XFPREGS 1673 fpu_free: 1674 kfree(info->fpu); 1675 #endif 1676 prstatus_free: 1677 kfree(info->prstatus); 1678 psinfo_free: 1679 kfree(info->psinfo); 1680 notes_free: 1681 kfree(info->notes); 1682 return 0; 1683 } 1684 1685 static int fill_note_info(struct elfhdr *elf, int phdrs, 1686 struct elf_note_info *info, 1687 long signr, struct pt_regs *regs) 1688 { 1689 struct list_head *t; 1690 1691 if (!elf_note_info_init(info)) 1692 return 0; 1693 1694 if (signr) { 1695 struct core_thread *ct; 1696 struct elf_thread_status *ets; 1697 1698 for (ct = current->mm->core_state->dumper.next; 1699 ct; ct = ct->next) { 1700 ets = kzalloc(sizeof(*ets), GFP_KERNEL); 1701 if (!ets) 1702 return 0; 1703 1704 ets->thread = ct->task; 1705 list_add(&ets->list, &info->thread_list); 1706 } 1707 1708 list_for_each(t, &info->thread_list) { 1709 int sz; 1710 1711 ets = list_entry(t, struct elf_thread_status, list); 1712 sz = elf_dump_thread_status(signr, ets); 1713 info->thread_status_size += sz; 1714 } 1715 } 1716 /* now collect the dump for the current */ 1717 memset(info->prstatus, 0, sizeof(*info->prstatus)); 1718 fill_prstatus(info->prstatus, current, signr); 1719 elf_core_copy_regs(&info->prstatus->pr_reg, regs); 1720 1721 /* Set up header */ 1722 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI); 1723 1724 /* 1725 * Set up the notes in similar form to SVR4 core dumps made 1726 * with info from their /proc. 1727 */ 1728 1729 fill_note(info->notes + 0, "CORE", NT_PRSTATUS, 1730 sizeof(*info->prstatus), info->prstatus); 1731 fill_psinfo(info->psinfo, current->group_leader, current->mm); 1732 fill_note(info->notes + 1, "CORE", NT_PRPSINFO, 1733 sizeof(*info->psinfo), info->psinfo); 1734 1735 info->numnote = 2; 1736 1737 fill_auxv_note(&info->notes[info->numnote++], current->mm); 1738 1739 /* Try to dump the FPU. */ 1740 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs, 1741 info->fpu); 1742 if (info->prstatus->pr_fpvalid) 1743 fill_note(info->notes + info->numnote++, 1744 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu); 1745 #ifdef ELF_CORE_COPY_XFPREGS 1746 if (elf_core_copy_task_xfpregs(current, info->xfpu)) 1747 fill_note(info->notes + info->numnote++, 1748 "LINUX", ELF_CORE_XFPREG_TYPE, 1749 sizeof(*info->xfpu), info->xfpu); 1750 #endif 1751 1752 return 1; 1753 } 1754 1755 static size_t get_note_info_size(struct elf_note_info *info) 1756 { 1757 int sz = 0; 1758 int i; 1759 1760 for (i = 0; i < info->numnote; i++) 1761 sz += notesize(info->notes + i); 1762 1763 sz += info->thread_status_size; 1764 1765 return sz; 1766 } 1767 1768 static int write_note_info(struct elf_note_info *info, 1769 struct file *file, loff_t *foffset) 1770 { 1771 int i; 1772 struct list_head *t; 1773 1774 for (i = 0; i < info->numnote; i++) 1775 if (!writenote(info->notes + i, file, foffset)) 1776 return 0; 1777 1778 /* write out the thread status notes section */ 1779 list_for_each(t, &info->thread_list) { 1780 struct elf_thread_status *tmp = 1781 list_entry(t, struct elf_thread_status, list); 1782 1783 for (i = 0; i < tmp->num_notes; i++) 1784 if (!writenote(&tmp->notes[i], file, foffset)) 1785 return 0; 1786 } 1787 1788 return 1; 1789 } 1790 1791 static void free_note_info(struct elf_note_info *info) 1792 { 1793 while (!list_empty(&info->thread_list)) { 1794 struct list_head *tmp = info->thread_list.next; 1795 list_del(tmp); 1796 kfree(list_entry(tmp, struct elf_thread_status, list)); 1797 } 1798 1799 kfree(info->prstatus); 1800 kfree(info->psinfo); 1801 kfree(info->notes); 1802 kfree(info->fpu); 1803 #ifdef ELF_CORE_COPY_XFPREGS 1804 kfree(info->xfpu); 1805 #endif 1806 } 1807 1808 #endif 1809 1810 static struct vm_area_struct *first_vma(struct task_struct *tsk, 1811 struct vm_area_struct *gate_vma) 1812 { 1813 struct vm_area_struct *ret = tsk->mm->mmap; 1814 1815 if (ret) 1816 return ret; 1817 return gate_vma; 1818 } 1819 /* 1820 * Helper function for iterating across a vma list. It ensures that the caller 1821 * will visit `gate_vma' prior to terminating the search. 1822 */ 1823 static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, 1824 struct vm_area_struct *gate_vma) 1825 { 1826 struct vm_area_struct *ret; 1827 1828 ret = this_vma->vm_next; 1829 if (ret) 1830 return ret; 1831 if (this_vma == gate_vma) 1832 return NULL; 1833 return gate_vma; 1834 } 1835 1836 static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum, 1837 elf_addr_t e_shoff, int segs) 1838 { 1839 elf->e_shoff = e_shoff; 1840 elf->e_shentsize = sizeof(*shdr4extnum); 1841 elf->e_shnum = 1; 1842 elf->e_shstrndx = SHN_UNDEF; 1843 1844 memset(shdr4extnum, 0, sizeof(*shdr4extnum)); 1845 1846 shdr4extnum->sh_type = SHT_NULL; 1847 shdr4extnum->sh_size = elf->e_shnum; 1848 shdr4extnum->sh_link = elf->e_shstrndx; 1849 shdr4extnum->sh_info = segs; 1850 } 1851 1852 static size_t elf_core_vma_data_size(struct vm_area_struct *gate_vma, 1853 unsigned long mm_flags) 1854 { 1855 struct vm_area_struct *vma; 1856 size_t size = 0; 1857 1858 for (vma = first_vma(current, gate_vma); vma != NULL; 1859 vma = next_vma(vma, gate_vma)) 1860 size += vma_dump_size(vma, mm_flags); 1861 return size; 1862 } 1863 1864 /* 1865 * Actual dumper 1866 * 1867 * This is a two-pass process; first we find the offsets of the bits, 1868 * and then they are actually written out. If we run out of core limit 1869 * we just truncate. 1870 */ 1871 static int elf_core_dump(struct coredump_params *cprm) 1872 { 1873 int has_dumped = 0; 1874 mm_segment_t fs; 1875 int segs; 1876 size_t size = 0; 1877 struct vm_area_struct *vma, *gate_vma; 1878 struct elfhdr *elf = NULL; 1879 loff_t offset = 0, dataoff, foffset; 1880 struct elf_note_info info; 1881 struct elf_phdr *phdr4note = NULL; 1882 struct elf_shdr *shdr4extnum = NULL; 1883 Elf_Half e_phnum; 1884 elf_addr_t e_shoff; 1885 1886 /* 1887 * We no longer stop all VM operations. 1888 * 1889 * This is because those proceses that could possibly change map_count 1890 * or the mmap / vma pages are now blocked in do_exit on current 1891 * finishing this core dump. 1892 * 1893 * Only ptrace can touch these memory addresses, but it doesn't change 1894 * the map_count or the pages allocated. So no possibility of crashing 1895 * exists while dumping the mm->vm_next areas to the core file. 1896 */ 1897 1898 /* alloc memory for large data structures: too large to be on stack */ 1899 elf = kmalloc(sizeof(*elf), GFP_KERNEL); 1900 if (!elf) 1901 goto out; 1902 /* 1903 * The number of segs are recored into ELF header as 16bit value. 1904 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here. 1905 */ 1906 segs = current->mm->map_count; 1907 segs += elf_core_extra_phdrs(); 1908 1909 gate_vma = get_gate_vma(current); 1910 if (gate_vma != NULL) 1911 segs++; 1912 1913 /* for notes section */ 1914 segs++; 1915 1916 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid 1917 * this, kernel supports extended numbering. Have a look at 1918 * include/linux/elf.h for further information. */ 1919 e_phnum = segs > PN_XNUM ? PN_XNUM : segs; 1920 1921 /* 1922 * Collect all the non-memory information about the process for the 1923 * notes. This also sets up the file header. 1924 */ 1925 if (!fill_note_info(elf, e_phnum, &info, cprm->signr, cprm->regs)) 1926 goto cleanup; 1927 1928 has_dumped = 1; 1929 current->flags |= PF_DUMPCORE; 1930 1931 fs = get_fs(); 1932 set_fs(KERNEL_DS); 1933 1934 offset += sizeof(*elf); /* Elf header */ 1935 offset += segs * sizeof(struct elf_phdr); /* Program headers */ 1936 foffset = offset; 1937 1938 /* Write notes phdr entry */ 1939 { 1940 size_t sz = get_note_info_size(&info); 1941 1942 sz += elf_coredump_extra_notes_size(); 1943 1944 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL); 1945 if (!phdr4note) 1946 goto end_coredump; 1947 1948 fill_elf_note_phdr(phdr4note, sz, offset); 1949 offset += sz; 1950 } 1951 1952 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); 1953 1954 offset += elf_core_vma_data_size(gate_vma, cprm->mm_flags); 1955 offset += elf_core_extra_data_size(); 1956 e_shoff = offset; 1957 1958 if (e_phnum == PN_XNUM) { 1959 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL); 1960 if (!shdr4extnum) 1961 goto end_coredump; 1962 fill_extnum_info(elf, shdr4extnum, e_shoff, segs); 1963 } 1964 1965 offset = dataoff; 1966 1967 size += sizeof(*elf); 1968 if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf))) 1969 goto end_coredump; 1970 1971 size += sizeof(*phdr4note); 1972 if (size > cprm->limit 1973 || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note))) 1974 goto end_coredump; 1975 1976 /* Write program headers for segments dump */ 1977 for (vma = first_vma(current, gate_vma); vma != NULL; 1978 vma = next_vma(vma, gate_vma)) { 1979 struct elf_phdr phdr; 1980 1981 phdr.p_type = PT_LOAD; 1982 phdr.p_offset = offset; 1983 phdr.p_vaddr = vma->vm_start; 1984 phdr.p_paddr = 0; 1985 phdr.p_filesz = vma_dump_size(vma, cprm->mm_flags); 1986 phdr.p_memsz = vma->vm_end - vma->vm_start; 1987 offset += phdr.p_filesz; 1988 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0; 1989 if (vma->vm_flags & VM_WRITE) 1990 phdr.p_flags |= PF_W; 1991 if (vma->vm_flags & VM_EXEC) 1992 phdr.p_flags |= PF_X; 1993 phdr.p_align = ELF_EXEC_PAGESIZE; 1994 1995 size += sizeof(phdr); 1996 if (size > cprm->limit 1997 || !dump_write(cprm->file, &phdr, sizeof(phdr))) 1998 goto end_coredump; 1999 } 2000 2001 if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit)) 2002 goto end_coredump; 2003 2004 /* write out the notes section */ 2005 if (!write_note_info(&info, cprm->file, &foffset)) 2006 goto end_coredump; 2007 2008 if (elf_coredump_extra_notes_write(cprm->file, &foffset)) 2009 goto end_coredump; 2010 2011 /* Align to page */ 2012 if (!dump_seek(cprm->file, dataoff - foffset)) 2013 goto end_coredump; 2014 2015 for (vma = first_vma(current, gate_vma); vma != NULL; 2016 vma = next_vma(vma, gate_vma)) { 2017 unsigned long addr; 2018 unsigned long end; 2019 2020 end = vma->vm_start + vma_dump_size(vma, cprm->mm_flags); 2021 2022 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) { 2023 struct page *page; 2024 int stop; 2025 2026 page = get_dump_page(addr); 2027 if (page) { 2028 void *kaddr = kmap(page); 2029 stop = ((size += PAGE_SIZE) > cprm->limit) || 2030 !dump_write(cprm->file, kaddr, 2031 PAGE_SIZE); 2032 kunmap(page); 2033 page_cache_release(page); 2034 } else 2035 stop = !dump_seek(cprm->file, PAGE_SIZE); 2036 if (stop) 2037 goto end_coredump; 2038 } 2039 } 2040 2041 if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit)) 2042 goto end_coredump; 2043 2044 if (e_phnum == PN_XNUM) { 2045 size += sizeof(*shdr4extnum); 2046 if (size > cprm->limit 2047 || !dump_write(cprm->file, shdr4extnum, 2048 sizeof(*shdr4extnum))) 2049 goto end_coredump; 2050 } 2051 2052 end_coredump: 2053 set_fs(fs); 2054 2055 cleanup: 2056 free_note_info(&info); 2057 kfree(shdr4extnum); 2058 kfree(phdr4note); 2059 kfree(elf); 2060 out: 2061 return has_dumped; 2062 } 2063 2064 #endif /* CONFIG_ELF_CORE */ 2065 2066 static int __init init_elf_binfmt(void) 2067 { 2068 return register_binfmt(&elf_format); 2069 } 2070 2071 static void __exit exit_elf_binfmt(void) 2072 { 2073 /* Remove the COFF and ELF loaders. */ 2074 unregister_binfmt(&elf_format); 2075 } 2076 2077 core_initcall(init_elf_binfmt); 2078 module_exit(exit_elf_binfmt); 2079 MODULE_LICENSE("GPL"); 2080