Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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/stat.h> |
| 16 | #include <linux/time.h> |
| 17 | #include <linux/mm.h> |
| 18 | #include <linux/mman.h> |
| 19 | #include <linux/a.out.h> |
| 20 | #include <linux/errno.h> |
| 21 | #include <linux/signal.h> |
| 22 | #include <linux/binfmts.h> |
| 23 | #include <linux/string.h> |
| 24 | #include <linux/file.h> |
| 25 | #include <linux/fcntl.h> |
| 26 | #include <linux/ptrace.h> |
| 27 | #include <linux/slab.h> |
| 28 | #include <linux/shm.h> |
| 29 | #include <linux/personality.h> |
| 30 | #include <linux/elfcore.h> |
| 31 | #include <linux/init.h> |
| 32 | #include <linux/highuid.h> |
| 33 | #include <linux/smp.h> |
| 34 | #include <linux/smp_lock.h> |
| 35 | #include <linux/compiler.h> |
| 36 | #include <linux/highmem.h> |
| 37 | #include <linux/pagemap.h> |
| 38 | #include <linux/security.h> |
| 39 | #include <linux/syscalls.h> |
| 40 | #include <linux/random.h> |
| 41 | |
| 42 | #include <asm/uaccess.h> |
| 43 | #include <asm/param.h> |
| 44 | #include <asm/page.h> |
| 45 | |
| 46 | #include <linux/elf.h> |
| 47 | |
| 48 | static int load_elf_binary(struct linux_binprm * bprm, struct pt_regs * regs); |
| 49 | static int load_elf_library(struct file*); |
| 50 | static unsigned long elf_map (struct file *, unsigned long, struct elf_phdr *, int, int); |
| 51 | extern int dump_fpu (struct pt_regs *, elf_fpregset_t *); |
| 52 | |
| 53 | #ifndef elf_addr_t |
| 54 | #define elf_addr_t unsigned long |
| 55 | #endif |
| 56 | |
| 57 | /* |
| 58 | * If we don't support core dumping, then supply a NULL so we |
| 59 | * don't even try. |
| 60 | */ |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 61 | #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | static int elf_core_dump(long signr, struct pt_regs * regs, struct file * file); |
| 63 | #else |
| 64 | #define elf_core_dump NULL |
| 65 | #endif |
| 66 | |
| 67 | #if ELF_EXEC_PAGESIZE > PAGE_SIZE |
| 68 | # define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE |
| 69 | #else |
| 70 | # define ELF_MIN_ALIGN PAGE_SIZE |
| 71 | #endif |
| 72 | |
| 73 | #ifndef ELF_CORE_EFLAGS |
| 74 | #define ELF_CORE_EFLAGS 0 |
| 75 | #endif |
| 76 | |
| 77 | #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1)) |
| 78 | #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1)) |
| 79 | #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1)) |
| 80 | |
| 81 | static struct linux_binfmt elf_format = { |
| 82 | .module = THIS_MODULE, |
| 83 | .load_binary = load_elf_binary, |
| 84 | .load_shlib = load_elf_library, |
| 85 | .core_dump = elf_core_dump, |
| 86 | .min_coredump = ELF_EXEC_PAGESIZE |
| 87 | }; |
| 88 | |
| 89 | #define BAD_ADDR(x) ((unsigned long)(x) > TASK_SIZE) |
| 90 | |
| 91 | static int set_brk(unsigned long start, unsigned long end) |
| 92 | { |
| 93 | start = ELF_PAGEALIGN(start); |
| 94 | end = ELF_PAGEALIGN(end); |
| 95 | if (end > start) { |
| 96 | unsigned long addr; |
| 97 | down_write(¤t->mm->mmap_sem); |
| 98 | addr = do_brk(start, end - start); |
| 99 | up_write(¤t->mm->mmap_sem); |
| 100 | if (BAD_ADDR(addr)) |
| 101 | return addr; |
| 102 | } |
| 103 | current->mm->start_brk = current->mm->brk = end; |
| 104 | return 0; |
| 105 | } |
| 106 | |
| 107 | |
| 108 | /* We need to explicitly zero any fractional pages |
| 109 | after the data section (i.e. bss). This would |
| 110 | contain the junk from the file that should not |
| 111 | be in memory */ |
| 112 | |
| 113 | |
| 114 | static int padzero(unsigned long elf_bss) |
| 115 | { |
| 116 | unsigned long nbyte; |
| 117 | |
| 118 | nbyte = ELF_PAGEOFFSET(elf_bss); |
| 119 | if (nbyte) { |
| 120 | nbyte = ELF_MIN_ALIGN - nbyte; |
| 121 | if (clear_user((void __user *) elf_bss, nbyte)) |
| 122 | return -EFAULT; |
| 123 | } |
| 124 | return 0; |
| 125 | } |
| 126 | |
| 127 | /* Let's use some macros to make this stack manipulation a litle clearer */ |
| 128 | #ifdef CONFIG_STACK_GROWSUP |
| 129 | #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items)) |
| 130 | #define STACK_ROUND(sp, items) \ |
| 131 | ((15 + (unsigned long) ((sp) + (items))) &~ 15UL) |
| 132 | #define STACK_ALLOC(sp, len) ({ elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; old_sp; }) |
| 133 | #else |
| 134 | #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items)) |
| 135 | #define STACK_ROUND(sp, items) \ |
| 136 | (((unsigned long) (sp - items)) &~ 15UL) |
| 137 | #define STACK_ALLOC(sp, len) ({ sp -= len ; sp; }) |
| 138 | #endif |
| 139 | |
| 140 | static int |
| 141 | create_elf_tables(struct linux_binprm *bprm, struct elfhdr * exec, |
| 142 | int interp_aout, unsigned long load_addr, |
| 143 | unsigned long interp_load_addr) |
| 144 | { |
| 145 | unsigned long p = bprm->p; |
| 146 | int argc = bprm->argc; |
| 147 | int envc = bprm->envc; |
| 148 | elf_addr_t __user *argv; |
| 149 | elf_addr_t __user *envp; |
| 150 | elf_addr_t __user *sp; |
| 151 | elf_addr_t __user *u_platform; |
| 152 | const char *k_platform = ELF_PLATFORM; |
| 153 | int items; |
| 154 | elf_addr_t *elf_info; |
| 155 | int ei_index = 0; |
| 156 | struct task_struct *tsk = current; |
| 157 | |
| 158 | /* |
| 159 | * If this architecture has a platform capability string, copy it |
| 160 | * to userspace. In some cases (Sparc), this info is impossible |
| 161 | * for userspace to get any other way, in others (i386) it is |
| 162 | * merely difficult. |
| 163 | */ |
| 164 | |
| 165 | u_platform = NULL; |
| 166 | if (k_platform) { |
| 167 | size_t len = strlen(k_platform) + 1; |
| 168 | |
| 169 | /* |
| 170 | * In some cases (e.g. Hyper-Threading), we want to avoid L1 |
| 171 | * evictions by the processes running on the same package. One |
| 172 | * thing we can do is to shuffle the initial stack for them. |
| 173 | */ |
| 174 | |
| 175 | p = arch_align_stack(p); |
| 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 | /* Create the ELF interpreter info */ |
| 183 | elf_info = (elf_addr_t *) current->mm->saved_auxv; |
| 184 | #define NEW_AUX_ENT(id, val) \ |
| 185 | do { elf_info[ei_index++] = id; elf_info[ei_index++] = val; } while (0) |
| 186 | |
| 187 | #ifdef ARCH_DLINFO |
| 188 | /* |
| 189 | * ARCH_DLINFO must come first so PPC can do its special alignment of |
| 190 | * AUXV. |
| 191 | */ |
| 192 | ARCH_DLINFO; |
| 193 | #endif |
| 194 | NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP); |
| 195 | NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE); |
| 196 | NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC); |
| 197 | NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff); |
| 198 | NEW_AUX_ENT(AT_PHENT, sizeof (struct elf_phdr)); |
| 199 | NEW_AUX_ENT(AT_PHNUM, exec->e_phnum); |
| 200 | NEW_AUX_ENT(AT_BASE, interp_load_addr); |
| 201 | NEW_AUX_ENT(AT_FLAGS, 0); |
| 202 | NEW_AUX_ENT(AT_ENTRY, exec->e_entry); |
| 203 | NEW_AUX_ENT(AT_UID, (elf_addr_t) tsk->uid); |
| 204 | NEW_AUX_ENT(AT_EUID, (elf_addr_t) tsk->euid); |
| 205 | NEW_AUX_ENT(AT_GID, (elf_addr_t) tsk->gid); |
| 206 | NEW_AUX_ENT(AT_EGID, (elf_addr_t) tsk->egid); |
| 207 | NEW_AUX_ENT(AT_SECURE, (elf_addr_t) security_bprm_secureexec(bprm)); |
| 208 | if (k_platform) { |
| 209 | NEW_AUX_ENT(AT_PLATFORM, (elf_addr_t)(unsigned long)u_platform); |
| 210 | } |
| 211 | if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) { |
| 212 | NEW_AUX_ENT(AT_EXECFD, (elf_addr_t) bprm->interp_data); |
| 213 | } |
| 214 | #undef NEW_AUX_ENT |
| 215 | /* AT_NULL is zero; clear the rest too */ |
| 216 | memset(&elf_info[ei_index], 0, |
| 217 | sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]); |
| 218 | |
| 219 | /* And advance past the AT_NULL entry. */ |
| 220 | ei_index += 2; |
| 221 | |
| 222 | sp = STACK_ADD(p, ei_index); |
| 223 | |
| 224 | items = (argc + 1) + (envc + 1); |
| 225 | if (interp_aout) { |
| 226 | items += 3; /* a.out interpreters require argv & envp too */ |
| 227 | } else { |
| 228 | items += 1; /* ELF interpreters only put argc on the stack */ |
| 229 | } |
| 230 | bprm->p = STACK_ROUND(sp, items); |
| 231 | |
| 232 | /* Point sp at the lowest address on the stack */ |
| 233 | #ifdef CONFIG_STACK_GROWSUP |
| 234 | sp = (elf_addr_t __user *)bprm->p - items - ei_index; |
| 235 | bprm->exec = (unsigned long) sp; /* XXX: PARISC HACK */ |
| 236 | #else |
| 237 | sp = (elf_addr_t __user *)bprm->p; |
| 238 | #endif |
| 239 | |
| 240 | /* Now, let's put argc (and argv, envp if appropriate) on the stack */ |
| 241 | if (__put_user(argc, sp++)) |
| 242 | return -EFAULT; |
| 243 | if (interp_aout) { |
| 244 | argv = sp + 2; |
| 245 | envp = argv + argc + 1; |
| 246 | __put_user((elf_addr_t)(unsigned long)argv, sp++); |
| 247 | __put_user((elf_addr_t)(unsigned long)envp, sp++); |
| 248 | } else { |
| 249 | argv = sp; |
| 250 | envp = argv + argc + 1; |
| 251 | } |
| 252 | |
| 253 | /* Populate argv and envp */ |
Greg Kroah-Hartman | a84a505 | 2005-05-11 00:10:44 -0700 | [diff] [blame] | 254 | p = current->mm->arg_end = current->mm->arg_start; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | while (argc-- > 0) { |
| 256 | size_t len; |
| 257 | __put_user((elf_addr_t)p, argv++); |
| 258 | len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES); |
| 259 | if (!len || len > PAGE_SIZE*MAX_ARG_PAGES) |
| 260 | return 0; |
| 261 | p += len; |
| 262 | } |
| 263 | if (__put_user(0, argv)) |
| 264 | return -EFAULT; |
| 265 | current->mm->arg_end = current->mm->env_start = p; |
| 266 | while (envc-- > 0) { |
| 267 | size_t len; |
| 268 | __put_user((elf_addr_t)p, envp++); |
| 269 | len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES); |
| 270 | if (!len || len > PAGE_SIZE*MAX_ARG_PAGES) |
| 271 | return 0; |
| 272 | p += len; |
| 273 | } |
| 274 | if (__put_user(0, envp)) |
| 275 | return -EFAULT; |
| 276 | current->mm->env_end = p; |
| 277 | |
| 278 | /* Put the elf_info on the stack in the right place. */ |
| 279 | sp = (elf_addr_t __user *)envp + 1; |
| 280 | if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t))) |
| 281 | return -EFAULT; |
| 282 | return 0; |
| 283 | } |
| 284 | |
| 285 | #ifndef elf_map |
| 286 | |
| 287 | static unsigned long elf_map(struct file *filep, unsigned long addr, |
| 288 | struct elf_phdr *eppnt, int prot, int type) |
| 289 | { |
| 290 | unsigned long map_addr; |
David Gibson | dda6ebd | 2006-01-08 01:03:35 -0800 | [diff] [blame] | 291 | unsigned long pageoffset = ELF_PAGEOFFSET(eppnt->p_vaddr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | |
| 293 | down_write(¤t->mm->mmap_sem); |
David Gibson | dda6ebd | 2006-01-08 01:03:35 -0800 | [diff] [blame] | 294 | /* mmap() will return -EINVAL if given a zero size, but a |
| 295 | * segment with zero filesize is perfectly valid */ |
| 296 | if (eppnt->p_filesz + pageoffset) |
| 297 | map_addr = do_mmap(filep, ELF_PAGESTART(addr), |
| 298 | eppnt->p_filesz + pageoffset, prot, type, |
| 299 | eppnt->p_offset - pageoffset); |
| 300 | else |
| 301 | map_addr = ELF_PAGESTART(addr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | up_write(¤t->mm->mmap_sem); |
| 303 | return(map_addr); |
| 304 | } |
| 305 | |
| 306 | #endif /* !elf_map */ |
| 307 | |
| 308 | /* This is much more generalized than the library routine read function, |
| 309 | so we keep this separate. Technically the library read function |
| 310 | is only provided so that we can read a.out libraries that have |
| 311 | an ELF header */ |
| 312 | |
| 313 | static unsigned long load_elf_interp(struct elfhdr * interp_elf_ex, |
| 314 | struct file * interpreter, |
| 315 | unsigned long *interp_load_addr) |
| 316 | { |
| 317 | struct elf_phdr *elf_phdata; |
| 318 | struct elf_phdr *eppnt; |
| 319 | unsigned long load_addr = 0; |
| 320 | int load_addr_set = 0; |
| 321 | unsigned long last_bss = 0, elf_bss = 0; |
| 322 | unsigned long error = ~0UL; |
| 323 | int retval, i, size; |
| 324 | |
| 325 | /* First of all, some simple consistency checks */ |
| 326 | if (interp_elf_ex->e_type != ET_EXEC && |
| 327 | interp_elf_ex->e_type != ET_DYN) |
| 328 | goto out; |
| 329 | if (!elf_check_arch(interp_elf_ex)) |
| 330 | goto out; |
| 331 | if (!interpreter->f_op || !interpreter->f_op->mmap) |
| 332 | goto out; |
| 333 | |
| 334 | /* |
| 335 | * If the size of this structure has changed, then punt, since |
| 336 | * we will be doing the wrong thing. |
| 337 | */ |
| 338 | if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr)) |
| 339 | goto out; |
| 340 | if (interp_elf_ex->e_phnum < 1 || |
| 341 | interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr)) |
| 342 | goto out; |
| 343 | |
| 344 | /* Now read in all of the header information */ |
| 345 | |
| 346 | size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum; |
| 347 | if (size > ELF_MIN_ALIGN) |
| 348 | goto out; |
| 349 | elf_phdata = (struct elf_phdr *) kmalloc(size, GFP_KERNEL); |
| 350 | if (!elf_phdata) |
| 351 | goto out; |
| 352 | |
| 353 | retval = kernel_read(interpreter,interp_elf_ex->e_phoff,(char *)elf_phdata,size); |
| 354 | error = -EIO; |
| 355 | if (retval != size) { |
| 356 | if (retval < 0) |
| 357 | error = retval; |
| 358 | goto out_close; |
| 359 | } |
| 360 | |
| 361 | eppnt = elf_phdata; |
| 362 | for (i=0; i<interp_elf_ex->e_phnum; i++, eppnt++) { |
| 363 | if (eppnt->p_type == PT_LOAD) { |
| 364 | int elf_type = MAP_PRIVATE | MAP_DENYWRITE; |
| 365 | int elf_prot = 0; |
| 366 | unsigned long vaddr = 0; |
| 367 | unsigned long k, map_addr; |
| 368 | |
| 369 | if (eppnt->p_flags & PF_R) elf_prot = PROT_READ; |
| 370 | if (eppnt->p_flags & PF_W) elf_prot |= PROT_WRITE; |
| 371 | if (eppnt->p_flags & PF_X) elf_prot |= PROT_EXEC; |
| 372 | vaddr = eppnt->p_vaddr; |
| 373 | if (interp_elf_ex->e_type == ET_EXEC || load_addr_set) |
| 374 | elf_type |= MAP_FIXED; |
| 375 | |
| 376 | map_addr = elf_map(interpreter, load_addr + vaddr, eppnt, elf_prot, elf_type); |
| 377 | error = map_addr; |
| 378 | if (BAD_ADDR(map_addr)) |
| 379 | goto out_close; |
| 380 | |
| 381 | if (!load_addr_set && interp_elf_ex->e_type == ET_DYN) { |
| 382 | load_addr = map_addr - ELF_PAGESTART(vaddr); |
| 383 | load_addr_set = 1; |
| 384 | } |
| 385 | |
| 386 | /* |
| 387 | * Check to see if the section's size will overflow the |
| 388 | * allowed task size. Note that p_filesz must always be |
| 389 | * <= p_memsize so it is only necessary to check p_memsz. |
| 390 | */ |
| 391 | k = load_addr + eppnt->p_vaddr; |
| 392 | if (k > TASK_SIZE || eppnt->p_filesz > eppnt->p_memsz || |
| 393 | eppnt->p_memsz > TASK_SIZE || TASK_SIZE - eppnt->p_memsz < k) { |
| 394 | error = -ENOMEM; |
| 395 | goto out_close; |
| 396 | } |
| 397 | |
| 398 | /* |
| 399 | * Find the end of the file mapping for this phdr, and keep |
| 400 | * track of the largest address we see for this. |
| 401 | */ |
| 402 | k = load_addr + eppnt->p_vaddr + eppnt->p_filesz; |
| 403 | if (k > elf_bss) |
| 404 | elf_bss = k; |
| 405 | |
| 406 | /* |
| 407 | * Do the same thing for the memory mapping - between |
| 408 | * elf_bss and last_bss is the bss section. |
| 409 | */ |
| 410 | k = load_addr + eppnt->p_memsz + eppnt->p_vaddr; |
| 411 | if (k > last_bss) |
| 412 | last_bss = k; |
| 413 | } |
| 414 | } |
| 415 | |
| 416 | /* |
| 417 | * Now fill out the bss section. First pad the last page up |
| 418 | * to the page boundary, and then perform a mmap to make sure |
| 419 | * that there are zero-mapped pages up to and including the |
| 420 | * last bss page. |
| 421 | */ |
| 422 | if (padzero(elf_bss)) { |
| 423 | error = -EFAULT; |
| 424 | goto out_close; |
| 425 | } |
| 426 | |
| 427 | elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1); /* What we have mapped so far */ |
| 428 | |
| 429 | /* Map the last of the bss segment */ |
| 430 | if (last_bss > elf_bss) { |
| 431 | down_write(¤t->mm->mmap_sem); |
| 432 | error = do_brk(elf_bss, last_bss - elf_bss); |
| 433 | up_write(¤t->mm->mmap_sem); |
| 434 | if (BAD_ADDR(error)) |
| 435 | goto out_close; |
| 436 | } |
| 437 | |
| 438 | *interp_load_addr = load_addr; |
| 439 | error = ((unsigned long) interp_elf_ex->e_entry) + load_addr; |
| 440 | |
| 441 | out_close: |
| 442 | kfree(elf_phdata); |
| 443 | out: |
| 444 | return error; |
| 445 | } |
| 446 | |
| 447 | static unsigned long load_aout_interp(struct exec * interp_ex, |
| 448 | struct file * interpreter) |
| 449 | { |
| 450 | unsigned long text_data, elf_entry = ~0UL; |
| 451 | char __user * addr; |
| 452 | loff_t offset; |
| 453 | |
| 454 | current->mm->end_code = interp_ex->a_text; |
| 455 | text_data = interp_ex->a_text + interp_ex->a_data; |
| 456 | current->mm->end_data = text_data; |
| 457 | current->mm->brk = interp_ex->a_bss + text_data; |
| 458 | |
| 459 | switch (N_MAGIC(*interp_ex)) { |
| 460 | case OMAGIC: |
| 461 | offset = 32; |
| 462 | addr = (char __user *)0; |
| 463 | break; |
| 464 | case ZMAGIC: |
| 465 | case QMAGIC: |
| 466 | offset = N_TXTOFF(*interp_ex); |
| 467 | addr = (char __user *) N_TXTADDR(*interp_ex); |
| 468 | break; |
| 469 | default: |
| 470 | goto out; |
| 471 | } |
| 472 | |
| 473 | down_write(¤t->mm->mmap_sem); |
| 474 | do_brk(0, text_data); |
| 475 | up_write(¤t->mm->mmap_sem); |
| 476 | if (!interpreter->f_op || !interpreter->f_op->read) |
| 477 | goto out; |
| 478 | if (interpreter->f_op->read(interpreter, addr, text_data, &offset) < 0) |
| 479 | goto out; |
| 480 | flush_icache_range((unsigned long)addr, |
| 481 | (unsigned long)addr + text_data); |
| 482 | |
| 483 | |
| 484 | down_write(¤t->mm->mmap_sem); |
| 485 | do_brk(ELF_PAGESTART(text_data + ELF_MIN_ALIGN - 1), |
| 486 | interp_ex->a_bss); |
| 487 | up_write(¤t->mm->mmap_sem); |
| 488 | elf_entry = interp_ex->a_entry; |
| 489 | |
| 490 | out: |
| 491 | return elf_entry; |
| 492 | } |
| 493 | |
| 494 | /* |
| 495 | * These are the functions used to load ELF style executables and shared |
| 496 | * libraries. There is no binary dependent code anywhere else. |
| 497 | */ |
| 498 | |
| 499 | #define INTERPRETER_NONE 0 |
| 500 | #define INTERPRETER_AOUT 1 |
| 501 | #define INTERPRETER_ELF 2 |
| 502 | |
Andi Kleen | 913bd90 | 2006-03-25 16:29:09 +0100 | [diff] [blame] | 503 | #ifndef STACK_RND_MASK |
| 504 | #define STACK_RND_MASK 0x7ff /* with 4K pages 8MB of VA */ |
| 505 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | |
| 507 | static unsigned long randomize_stack_top(unsigned long stack_top) |
| 508 | { |
| 509 | unsigned int random_variable = 0; |
| 510 | |
Andi Kleen | 913bd90 | 2006-03-25 16:29:09 +0100 | [diff] [blame] | 511 | if (current->flags & PF_RANDOMIZE) { |
| 512 | random_variable = get_random_int() & STACK_RND_MASK; |
| 513 | random_variable <<= PAGE_SHIFT; |
| 514 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | #ifdef CONFIG_STACK_GROWSUP |
Andi Kleen | 913bd90 | 2006-03-25 16:29:09 +0100 | [diff] [blame] | 516 | return PAGE_ALIGN(stack_top) + random_variable; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 517 | #else |
Andi Kleen | 913bd90 | 2006-03-25 16:29:09 +0100 | [diff] [blame] | 518 | return PAGE_ALIGN(stack_top) - random_variable; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 519 | #endif |
| 520 | } |
| 521 | |
| 522 | static int load_elf_binary(struct linux_binprm * bprm, struct pt_regs * regs) |
| 523 | { |
| 524 | struct file *interpreter = NULL; /* to shut gcc up */ |
| 525 | unsigned long load_addr = 0, load_bias = 0; |
| 526 | int load_addr_set = 0; |
| 527 | char * elf_interpreter = NULL; |
| 528 | unsigned int interpreter_type = INTERPRETER_NONE; |
| 529 | unsigned char ibcs2_interpreter = 0; |
| 530 | unsigned long error; |
| 531 | struct elf_phdr * elf_ppnt, *elf_phdata; |
| 532 | unsigned long elf_bss, elf_brk; |
| 533 | int elf_exec_fileno; |
| 534 | int retval, i; |
| 535 | unsigned int size; |
| 536 | unsigned long elf_entry, interp_load_addr = 0; |
| 537 | unsigned long start_code, end_code, start_data, end_data; |
| 538 | unsigned long reloc_func_desc = 0; |
| 539 | char passed_fileno[6]; |
| 540 | struct files_struct *files; |
| 541 | int have_pt_gnu_stack, executable_stack = EXSTACK_DEFAULT; |
| 542 | unsigned long def_flags = 0; |
| 543 | struct { |
| 544 | struct elfhdr elf_ex; |
| 545 | struct elfhdr interp_elf_ex; |
| 546 | struct exec interp_ex; |
| 547 | } *loc; |
| 548 | |
| 549 | loc = kmalloc(sizeof(*loc), GFP_KERNEL); |
| 550 | if (!loc) { |
| 551 | retval = -ENOMEM; |
| 552 | goto out_ret; |
| 553 | } |
| 554 | |
| 555 | /* Get the exec-header */ |
| 556 | loc->elf_ex = *((struct elfhdr *) bprm->buf); |
| 557 | |
| 558 | retval = -ENOEXEC; |
| 559 | /* First of all, some simple consistency checks */ |
| 560 | if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0) |
| 561 | goto out; |
| 562 | |
| 563 | if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN) |
| 564 | goto out; |
| 565 | if (!elf_check_arch(&loc->elf_ex)) |
| 566 | goto out; |
| 567 | if (!bprm->file->f_op||!bprm->file->f_op->mmap) |
| 568 | goto out; |
| 569 | |
| 570 | /* Now read in all of the header information */ |
| 571 | |
| 572 | if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr)) |
| 573 | goto out; |
| 574 | if (loc->elf_ex.e_phnum < 1 || |
| 575 | loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr)) |
| 576 | goto out; |
| 577 | size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr); |
| 578 | retval = -ENOMEM; |
| 579 | elf_phdata = (struct elf_phdr *) kmalloc(size, GFP_KERNEL); |
| 580 | if (!elf_phdata) |
| 581 | goto out; |
| 582 | |
| 583 | retval = kernel_read(bprm->file, loc->elf_ex.e_phoff, (char *) elf_phdata, size); |
| 584 | if (retval != size) { |
| 585 | if (retval >= 0) |
| 586 | retval = -EIO; |
| 587 | goto out_free_ph; |
| 588 | } |
| 589 | |
| 590 | files = current->files; /* Refcounted so ok */ |
| 591 | retval = unshare_files(); |
| 592 | if (retval < 0) |
| 593 | goto out_free_ph; |
| 594 | if (files == current->files) { |
| 595 | put_files_struct(files); |
| 596 | files = NULL; |
| 597 | } |
| 598 | |
| 599 | /* exec will make our files private anyway, but for the a.out |
| 600 | loader stuff we need to do it earlier */ |
| 601 | |
| 602 | retval = get_unused_fd(); |
| 603 | if (retval < 0) |
| 604 | goto out_free_fh; |
| 605 | get_file(bprm->file); |
| 606 | fd_install(elf_exec_fileno = retval, bprm->file); |
| 607 | |
| 608 | elf_ppnt = elf_phdata; |
| 609 | elf_bss = 0; |
| 610 | elf_brk = 0; |
| 611 | |
| 612 | start_code = ~0UL; |
| 613 | end_code = 0; |
| 614 | start_data = 0; |
| 615 | end_data = 0; |
| 616 | |
| 617 | for (i = 0; i < loc->elf_ex.e_phnum; i++) { |
| 618 | if (elf_ppnt->p_type == PT_INTERP) { |
| 619 | /* This is the program interpreter used for |
| 620 | * shared libraries - for now assume that this |
| 621 | * is an a.out format binary |
| 622 | */ |
| 623 | |
| 624 | retval = -ENOEXEC; |
| 625 | if (elf_ppnt->p_filesz > PATH_MAX || |
| 626 | elf_ppnt->p_filesz < 2) |
| 627 | goto out_free_file; |
| 628 | |
| 629 | retval = -ENOMEM; |
Jesper Juhl | 792db3a | 2006-01-09 20:54:45 -0800 | [diff] [blame] | 630 | elf_interpreter = kmalloc(elf_ppnt->p_filesz, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | GFP_KERNEL); |
| 632 | if (!elf_interpreter) |
| 633 | goto out_free_file; |
| 634 | |
| 635 | retval = kernel_read(bprm->file, elf_ppnt->p_offset, |
| 636 | elf_interpreter, |
| 637 | elf_ppnt->p_filesz); |
| 638 | if (retval != elf_ppnt->p_filesz) { |
| 639 | if (retval >= 0) |
| 640 | retval = -EIO; |
| 641 | goto out_free_interp; |
| 642 | } |
| 643 | /* make sure path is NULL terminated */ |
| 644 | retval = -ENOEXEC; |
| 645 | if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0') |
| 646 | goto out_free_interp; |
| 647 | |
| 648 | /* If the program interpreter is one of these two, |
| 649 | * then assume an iBCS2 image. Otherwise assume |
| 650 | * a native linux image. |
| 651 | */ |
| 652 | if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 || |
| 653 | strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0) |
| 654 | ibcs2_interpreter = 1; |
| 655 | |
| 656 | /* |
| 657 | * The early SET_PERSONALITY here is so that the lookup |
| 658 | * for the interpreter happens in the namespace of the |
| 659 | * to-be-execed image. SET_PERSONALITY can select an |
| 660 | * alternate root. |
| 661 | * |
| 662 | * However, SET_PERSONALITY is NOT allowed to switch |
| 663 | * this task into the new images's memory mapping |
| 664 | * policy - that is, TASK_SIZE must still evaluate to |
| 665 | * that which is appropriate to the execing application. |
| 666 | * This is because exit_mmap() needs to have TASK_SIZE |
| 667 | * evaluate to the size of the old image. |
| 668 | * |
| 669 | * So if (say) a 64-bit application is execing a 32-bit |
| 670 | * application it is the architecture's responsibility |
| 671 | * to defer changing the value of TASK_SIZE until the |
| 672 | * switch really is going to happen - do this in |
| 673 | * flush_thread(). - akpm |
| 674 | */ |
| 675 | SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter); |
| 676 | |
| 677 | interpreter = open_exec(elf_interpreter); |
| 678 | retval = PTR_ERR(interpreter); |
| 679 | if (IS_ERR(interpreter)) |
| 680 | goto out_free_interp; |
| 681 | retval = kernel_read(interpreter, 0, bprm->buf, BINPRM_BUF_SIZE); |
| 682 | if (retval != BINPRM_BUF_SIZE) { |
| 683 | if (retval >= 0) |
| 684 | retval = -EIO; |
| 685 | goto out_free_dentry; |
| 686 | } |
| 687 | |
| 688 | /* Get the exec headers */ |
| 689 | loc->interp_ex = *((struct exec *) bprm->buf); |
| 690 | loc->interp_elf_ex = *((struct elfhdr *) bprm->buf); |
| 691 | break; |
| 692 | } |
| 693 | elf_ppnt++; |
| 694 | } |
| 695 | |
| 696 | elf_ppnt = elf_phdata; |
| 697 | for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) |
| 698 | if (elf_ppnt->p_type == PT_GNU_STACK) { |
| 699 | if (elf_ppnt->p_flags & PF_X) |
| 700 | executable_stack = EXSTACK_ENABLE_X; |
| 701 | else |
| 702 | executable_stack = EXSTACK_DISABLE_X; |
| 703 | break; |
| 704 | } |
| 705 | have_pt_gnu_stack = (i < loc->elf_ex.e_phnum); |
| 706 | |
| 707 | /* Some simple consistency checks for the interpreter */ |
| 708 | if (elf_interpreter) { |
| 709 | interpreter_type = INTERPRETER_ELF | INTERPRETER_AOUT; |
| 710 | |
| 711 | /* Now figure out which format our binary is */ |
| 712 | if ((N_MAGIC(loc->interp_ex) != OMAGIC) && |
| 713 | (N_MAGIC(loc->interp_ex) != ZMAGIC) && |
| 714 | (N_MAGIC(loc->interp_ex) != QMAGIC)) |
| 715 | interpreter_type = INTERPRETER_ELF; |
| 716 | |
| 717 | if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0) |
| 718 | interpreter_type &= ~INTERPRETER_ELF; |
| 719 | |
| 720 | retval = -ELIBBAD; |
| 721 | if (!interpreter_type) |
| 722 | goto out_free_dentry; |
| 723 | |
| 724 | /* Make sure only one type was selected */ |
| 725 | if ((interpreter_type & INTERPRETER_ELF) && |
| 726 | interpreter_type != INTERPRETER_ELF) { |
| 727 | // FIXME - ratelimit this before re-enabling |
| 728 | // printk(KERN_WARNING "ELF: Ambiguous type, using ELF\n"); |
| 729 | interpreter_type = INTERPRETER_ELF; |
| 730 | } |
| 731 | /* Verify the interpreter has a valid arch */ |
| 732 | if ((interpreter_type == INTERPRETER_ELF) && |
| 733 | !elf_check_arch(&loc->interp_elf_ex)) |
| 734 | goto out_free_dentry; |
| 735 | } else { |
| 736 | /* Executables without an interpreter also need a personality */ |
| 737 | SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter); |
| 738 | } |
| 739 | |
| 740 | /* OK, we are done with that, now set up the arg stuff, |
| 741 | and then start this sucker up */ |
| 742 | |
| 743 | if ((!bprm->sh_bang) && (interpreter_type == INTERPRETER_AOUT)) { |
| 744 | char *passed_p = passed_fileno; |
| 745 | sprintf(passed_fileno, "%d", elf_exec_fileno); |
| 746 | |
| 747 | if (elf_interpreter) { |
| 748 | retval = copy_strings_kernel(1, &passed_p, bprm); |
| 749 | if (retval) |
| 750 | goto out_free_dentry; |
| 751 | bprm->argc++; |
| 752 | } |
| 753 | } |
| 754 | |
| 755 | /* Flush all traces of the currently running executable */ |
| 756 | retval = flush_old_exec(bprm); |
| 757 | if (retval) |
| 758 | goto out_free_dentry; |
| 759 | |
| 760 | /* Discard our unneeded old files struct */ |
| 761 | if (files) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 762 | put_files_struct(files); |
| 763 | files = NULL; |
| 764 | } |
| 765 | |
| 766 | /* OK, This is the point of no return */ |
| 767 | current->mm->start_data = 0; |
| 768 | current->mm->end_data = 0; |
| 769 | current->mm->end_code = 0; |
| 770 | current->mm->mmap = NULL; |
| 771 | current->flags &= ~PF_FORKNOEXEC; |
| 772 | current->mm->def_flags = def_flags; |
| 773 | |
| 774 | /* Do this immediately, since STACK_TOP as used in setup_arg_pages |
| 775 | may depend on the personality. */ |
| 776 | SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter); |
| 777 | if (elf_read_implies_exec(loc->elf_ex, executable_stack)) |
| 778 | current->personality |= READ_IMPLIES_EXEC; |
| 779 | |
| 780 | if ( !(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) |
| 781 | current->flags |= PF_RANDOMIZE; |
| 782 | arch_pick_mmap_layout(current->mm); |
| 783 | |
| 784 | /* Do this so that we can load the interpreter, if need be. We will |
| 785 | change some of these later */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 786 | current->mm->free_area_cache = current->mm->mmap_base; |
Wolfgang Wander | 1363c3c | 2005-06-21 17:14:49 -0700 | [diff] [blame] | 787 | current->mm->cached_hole_size = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 788 | retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP), |
| 789 | executable_stack); |
| 790 | if (retval < 0) { |
| 791 | send_sig(SIGKILL, current, 0); |
| 792 | goto out_free_dentry; |
| 793 | } |
| 794 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 795 | current->mm->start_stack = bprm->p; |
| 796 | |
| 797 | /* Now we do a little grungy work by mmaping the ELF image into |
| 798 | the correct location in memory. At this point, we assume that |
| 799 | the image should be loaded at fixed address, not at a variable |
| 800 | address. */ |
| 801 | |
| 802 | for(i = 0, elf_ppnt = elf_phdata; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) { |
| 803 | int elf_prot = 0, elf_flags; |
| 804 | unsigned long k, vaddr; |
| 805 | |
| 806 | if (elf_ppnt->p_type != PT_LOAD) |
| 807 | continue; |
| 808 | |
| 809 | if (unlikely (elf_brk > elf_bss)) { |
| 810 | unsigned long nbyte; |
| 811 | |
| 812 | /* There was a PT_LOAD segment with p_memsz > p_filesz |
| 813 | before this one. Map anonymous pages, if needed, |
| 814 | and clear the area. */ |
| 815 | retval = set_brk (elf_bss + load_bias, |
| 816 | elf_brk + load_bias); |
| 817 | if (retval) { |
| 818 | send_sig(SIGKILL, current, 0); |
| 819 | goto out_free_dentry; |
| 820 | } |
| 821 | nbyte = ELF_PAGEOFFSET(elf_bss); |
| 822 | if (nbyte) { |
| 823 | nbyte = ELF_MIN_ALIGN - nbyte; |
| 824 | if (nbyte > elf_brk - elf_bss) |
| 825 | nbyte = elf_brk - elf_bss; |
| 826 | if (clear_user((void __user *)elf_bss + |
| 827 | load_bias, nbyte)) { |
| 828 | /* |
| 829 | * This bss-zeroing can fail if the ELF |
| 830 | * file specifies odd protections. So |
| 831 | * we don't check the return value |
| 832 | */ |
| 833 | } |
| 834 | } |
| 835 | } |
| 836 | |
| 837 | if (elf_ppnt->p_flags & PF_R) elf_prot |= PROT_READ; |
| 838 | if (elf_ppnt->p_flags & PF_W) elf_prot |= PROT_WRITE; |
| 839 | if (elf_ppnt->p_flags & PF_X) elf_prot |= PROT_EXEC; |
| 840 | |
| 841 | elf_flags = MAP_PRIVATE|MAP_DENYWRITE|MAP_EXECUTABLE; |
| 842 | |
| 843 | vaddr = elf_ppnt->p_vaddr; |
| 844 | if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) { |
| 845 | elf_flags |= MAP_FIXED; |
| 846 | } else if (loc->elf_ex.e_type == ET_DYN) { |
| 847 | /* Try and get dynamic programs out of the way of the default mmap |
| 848 | base, as well as whatever program they might try to exec. This |
| 849 | is because the brk will follow the loader, and is not movable. */ |
| 850 | load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr); |
| 851 | } |
| 852 | |
| 853 | error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt, elf_prot, elf_flags); |
| 854 | if (BAD_ADDR(error)) { |
| 855 | send_sig(SIGKILL, current, 0); |
| 856 | goto out_free_dentry; |
| 857 | } |
| 858 | |
| 859 | if (!load_addr_set) { |
| 860 | load_addr_set = 1; |
| 861 | load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset); |
| 862 | if (loc->elf_ex.e_type == ET_DYN) { |
| 863 | load_bias += error - |
| 864 | ELF_PAGESTART(load_bias + vaddr); |
| 865 | load_addr += load_bias; |
| 866 | reloc_func_desc = load_bias; |
| 867 | } |
| 868 | } |
| 869 | k = elf_ppnt->p_vaddr; |
| 870 | if (k < start_code) start_code = k; |
| 871 | if (start_data < k) start_data = k; |
| 872 | |
| 873 | /* |
| 874 | * Check to see if the section's size will overflow the |
| 875 | * allowed task size. Note that p_filesz must always be |
| 876 | * <= p_memsz so it is only necessary to check p_memsz. |
| 877 | */ |
| 878 | if (k > TASK_SIZE || elf_ppnt->p_filesz > elf_ppnt->p_memsz || |
| 879 | elf_ppnt->p_memsz > TASK_SIZE || |
| 880 | TASK_SIZE - elf_ppnt->p_memsz < k) { |
| 881 | /* set_brk can never work. Avoid overflows. */ |
| 882 | send_sig(SIGKILL, current, 0); |
| 883 | goto out_free_dentry; |
| 884 | } |
| 885 | |
| 886 | k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz; |
| 887 | |
| 888 | if (k > elf_bss) |
| 889 | elf_bss = k; |
| 890 | if ((elf_ppnt->p_flags & PF_X) && end_code < k) |
| 891 | end_code = k; |
| 892 | if (end_data < k) |
| 893 | end_data = k; |
| 894 | k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz; |
| 895 | if (k > elf_brk) |
| 896 | elf_brk = k; |
| 897 | } |
| 898 | |
| 899 | loc->elf_ex.e_entry += load_bias; |
| 900 | elf_bss += load_bias; |
| 901 | elf_brk += load_bias; |
| 902 | start_code += load_bias; |
| 903 | end_code += load_bias; |
| 904 | start_data += load_bias; |
| 905 | end_data += load_bias; |
| 906 | |
| 907 | /* Calling set_brk effectively mmaps the pages that we need |
| 908 | * for the bss and break sections. We must do this before |
| 909 | * mapping in the interpreter, to make sure it doesn't wind |
| 910 | * up getting placed where the bss needs to go. |
| 911 | */ |
| 912 | retval = set_brk(elf_bss, elf_brk); |
| 913 | if (retval) { |
| 914 | send_sig(SIGKILL, current, 0); |
| 915 | goto out_free_dentry; |
| 916 | } |
akpm@osdl.org | 6de5051 | 2005-10-11 08:29:08 -0700 | [diff] [blame] | 917 | if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 918 | send_sig(SIGSEGV, current, 0); |
| 919 | retval = -EFAULT; /* Nobody gets to see this, but.. */ |
| 920 | goto out_free_dentry; |
| 921 | } |
| 922 | |
| 923 | if (elf_interpreter) { |
| 924 | if (interpreter_type == INTERPRETER_AOUT) |
| 925 | elf_entry = load_aout_interp(&loc->interp_ex, |
| 926 | interpreter); |
| 927 | else |
| 928 | elf_entry = load_elf_interp(&loc->interp_elf_ex, |
| 929 | interpreter, |
| 930 | &interp_load_addr); |
| 931 | if (BAD_ADDR(elf_entry)) { |
| 932 | printk(KERN_ERR "Unable to load interpreter %.128s\n", |
| 933 | elf_interpreter); |
| 934 | force_sig(SIGSEGV, current); |
| 935 | retval = -ENOEXEC; /* Nobody gets to see this, but.. */ |
| 936 | goto out_free_dentry; |
| 937 | } |
| 938 | reloc_func_desc = interp_load_addr; |
| 939 | |
| 940 | allow_write_access(interpreter); |
| 941 | fput(interpreter); |
| 942 | kfree(elf_interpreter); |
| 943 | } else { |
| 944 | elf_entry = loc->elf_ex.e_entry; |
Suresh Siddha | 5342fba | 2006-02-26 04:18:28 +0100 | [diff] [blame] | 945 | if (BAD_ADDR(elf_entry)) { |
| 946 | send_sig(SIGSEGV, current, 0); |
| 947 | retval = -ENOEXEC; /* Nobody gets to see this, but.. */ |
| 948 | goto out_free_dentry; |
| 949 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 950 | } |
| 951 | |
| 952 | kfree(elf_phdata); |
| 953 | |
| 954 | if (interpreter_type != INTERPRETER_AOUT) |
| 955 | sys_close(elf_exec_fileno); |
| 956 | |
| 957 | set_binfmt(&elf_format); |
| 958 | |
Benjamin Herrenschmidt | 547ee84 | 2005-04-16 15:24:35 -0700 | [diff] [blame] | 959 | #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES |
| 960 | retval = arch_setup_additional_pages(bprm, executable_stack); |
| 961 | if (retval < 0) { |
| 962 | send_sig(SIGKILL, current, 0); |
Roland McGrath | 18c8baf | 2005-04-28 15:17:19 -0700 | [diff] [blame] | 963 | goto out; |
Benjamin Herrenschmidt | 547ee84 | 2005-04-16 15:24:35 -0700 | [diff] [blame] | 964 | } |
| 965 | #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */ |
| 966 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 967 | compute_creds(bprm); |
| 968 | current->flags &= ~PF_FORKNOEXEC; |
| 969 | create_elf_tables(bprm, &loc->elf_ex, (interpreter_type == INTERPRETER_AOUT), |
| 970 | load_addr, interp_load_addr); |
| 971 | /* N.B. passed_fileno might not be initialized? */ |
| 972 | if (interpreter_type == INTERPRETER_AOUT) |
| 973 | current->mm->arg_start += strlen(passed_fileno) + 1; |
| 974 | current->mm->end_code = end_code; |
| 975 | current->mm->start_code = start_code; |
| 976 | current->mm->start_data = start_data; |
| 977 | current->mm->end_data = end_data; |
| 978 | current->mm->start_stack = bprm->p; |
| 979 | |
| 980 | if (current->personality & MMAP_PAGE_ZERO) { |
| 981 | /* Why this, you ask??? Well SVr4 maps page 0 as read-only, |
| 982 | and some applications "depend" upon this behavior. |
| 983 | Since we do not have the power to recompile these, we |
| 984 | emulate the SVr4 behavior. Sigh. */ |
| 985 | down_write(¤t->mm->mmap_sem); |
| 986 | error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC, |
| 987 | MAP_FIXED | MAP_PRIVATE, 0); |
| 988 | up_write(¤t->mm->mmap_sem); |
| 989 | } |
| 990 | |
| 991 | #ifdef ELF_PLAT_INIT |
| 992 | /* |
| 993 | * The ABI may specify that certain registers be set up in special |
| 994 | * ways (on i386 %edx is the address of a DT_FINI function, for |
| 995 | * example. In addition, it may also specify (eg, PowerPC64 ELF) |
| 996 | * that the e_entry field is the address of the function descriptor |
| 997 | * for the startup routine, rather than the address of the startup |
| 998 | * routine itself. This macro performs whatever initialization to |
| 999 | * the regs structure is required as well as any relocations to the |
| 1000 | * function descriptor entries when executing dynamically links apps. |
| 1001 | */ |
| 1002 | ELF_PLAT_INIT(regs, reloc_func_desc); |
| 1003 | #endif |
| 1004 | |
| 1005 | start_thread(regs, elf_entry, bprm->p); |
| 1006 | if (unlikely(current->ptrace & PT_PTRACED)) { |
| 1007 | if (current->ptrace & PT_TRACE_EXEC) |
| 1008 | ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP); |
| 1009 | else |
| 1010 | send_sig(SIGTRAP, current, 0); |
| 1011 | } |
| 1012 | retval = 0; |
| 1013 | out: |
| 1014 | kfree(loc); |
| 1015 | out_ret: |
| 1016 | return retval; |
| 1017 | |
| 1018 | /* error cleanup */ |
| 1019 | out_free_dentry: |
| 1020 | allow_write_access(interpreter); |
| 1021 | if (interpreter) |
| 1022 | fput(interpreter); |
| 1023 | out_free_interp: |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 1024 | kfree(elf_interpreter); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1025 | out_free_file: |
| 1026 | sys_close(elf_exec_fileno); |
| 1027 | out_free_fh: |
| 1028 | if (files) { |
| 1029 | put_files_struct(current->files); |
| 1030 | current->files = files; |
| 1031 | } |
| 1032 | out_free_ph: |
| 1033 | kfree(elf_phdata); |
| 1034 | goto out; |
| 1035 | } |
| 1036 | |
| 1037 | /* This is really simpleminded and specialized - we are loading an |
| 1038 | a.out library that is given an ELF header. */ |
| 1039 | |
| 1040 | static int load_elf_library(struct file *file) |
| 1041 | { |
| 1042 | struct elf_phdr *elf_phdata; |
| 1043 | struct elf_phdr *eppnt; |
| 1044 | unsigned long elf_bss, bss, len; |
| 1045 | int retval, error, i, j; |
| 1046 | struct elfhdr elf_ex; |
| 1047 | |
| 1048 | error = -ENOEXEC; |
| 1049 | retval = kernel_read(file, 0, (char *) &elf_ex, sizeof(elf_ex)); |
| 1050 | if (retval != sizeof(elf_ex)) |
| 1051 | goto out; |
| 1052 | |
| 1053 | if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0) |
| 1054 | goto out; |
| 1055 | |
| 1056 | /* First of all, some simple consistency checks */ |
| 1057 | if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 || |
| 1058 | !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap) |
| 1059 | goto out; |
| 1060 | |
| 1061 | /* Now read in all of the header information */ |
| 1062 | |
| 1063 | j = sizeof(struct elf_phdr) * elf_ex.e_phnum; |
| 1064 | /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */ |
| 1065 | |
| 1066 | error = -ENOMEM; |
| 1067 | elf_phdata = kmalloc(j, GFP_KERNEL); |
| 1068 | if (!elf_phdata) |
| 1069 | goto out; |
| 1070 | |
| 1071 | eppnt = elf_phdata; |
| 1072 | error = -ENOEXEC; |
| 1073 | retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j); |
| 1074 | if (retval != j) |
| 1075 | goto out_free_ph; |
| 1076 | |
| 1077 | for (j = 0, i = 0; i<elf_ex.e_phnum; i++) |
| 1078 | if ((eppnt + i)->p_type == PT_LOAD) |
| 1079 | j++; |
| 1080 | if (j != 1) |
| 1081 | goto out_free_ph; |
| 1082 | |
| 1083 | while (eppnt->p_type != PT_LOAD) |
| 1084 | eppnt++; |
| 1085 | |
| 1086 | /* Now use mmap to map the library into memory. */ |
| 1087 | down_write(¤t->mm->mmap_sem); |
| 1088 | error = do_mmap(file, |
| 1089 | ELF_PAGESTART(eppnt->p_vaddr), |
| 1090 | (eppnt->p_filesz + |
| 1091 | ELF_PAGEOFFSET(eppnt->p_vaddr)), |
| 1092 | PROT_READ | PROT_WRITE | PROT_EXEC, |
| 1093 | MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, |
| 1094 | (eppnt->p_offset - |
| 1095 | ELF_PAGEOFFSET(eppnt->p_vaddr))); |
| 1096 | up_write(¤t->mm->mmap_sem); |
| 1097 | if (error != ELF_PAGESTART(eppnt->p_vaddr)) |
| 1098 | goto out_free_ph; |
| 1099 | |
| 1100 | elf_bss = eppnt->p_vaddr + eppnt->p_filesz; |
| 1101 | if (padzero(elf_bss)) { |
| 1102 | error = -EFAULT; |
| 1103 | goto out_free_ph; |
| 1104 | } |
| 1105 | |
| 1106 | len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr + ELF_MIN_ALIGN - 1); |
| 1107 | bss = eppnt->p_memsz + eppnt->p_vaddr; |
| 1108 | if (bss > len) { |
| 1109 | down_write(¤t->mm->mmap_sem); |
| 1110 | do_brk(len, bss - len); |
| 1111 | up_write(¤t->mm->mmap_sem); |
| 1112 | } |
| 1113 | error = 0; |
| 1114 | |
| 1115 | out_free_ph: |
| 1116 | kfree(elf_phdata); |
| 1117 | out: |
| 1118 | return error; |
| 1119 | } |
| 1120 | |
| 1121 | /* |
| 1122 | * Note that some platforms still use traditional core dumps and not |
| 1123 | * the ELF core dump. Each platform can select it as appropriate. |
| 1124 | */ |
Matt Mackall | 708e9a7 | 2006-01-08 01:05:25 -0800 | [diff] [blame] | 1125 | #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1126 | |
| 1127 | /* |
| 1128 | * ELF core dumper |
| 1129 | * |
| 1130 | * Modelled on fs/exec.c:aout_core_dump() |
| 1131 | * Jeremy Fitzhardinge <jeremy@sw.oz.au> |
| 1132 | */ |
| 1133 | /* |
| 1134 | * These are the only things you should do on a core-file: use only these |
| 1135 | * functions to write out all the necessary info. |
| 1136 | */ |
| 1137 | static int dump_write(struct file *file, const void *addr, int nr) |
| 1138 | { |
| 1139 | return file->f_op->write(file, addr, nr, &file->f_pos) == nr; |
| 1140 | } |
| 1141 | |
Daniel Jacobowitz | 5db9285 | 2005-06-15 22:26:34 -0700 | [diff] [blame] | 1142 | static int dump_seek(struct file *file, loff_t off) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1143 | { |
| 1144 | if (file->f_op->llseek) { |
| 1145 | if (file->f_op->llseek(file, off, 0) != off) |
| 1146 | return 0; |
| 1147 | } else |
| 1148 | file->f_pos = off; |
| 1149 | return 1; |
| 1150 | } |
| 1151 | |
| 1152 | /* |
| 1153 | * Decide whether a segment is worth dumping; default is yes to be |
| 1154 | * sure (missing info is worse than too much; etc). |
| 1155 | * Personally I'd include everything, and use the coredump limit... |
| 1156 | * |
| 1157 | * I think we should skip something. But I am not sure how. H.J. |
| 1158 | */ |
| 1159 | static int maydump(struct vm_area_struct *vma) |
| 1160 | { |
| 1161 | /* Do not dump I/O mapped devices or special mappings */ |
| 1162 | if (vma->vm_flags & (VM_IO | VM_RESERVED)) |
| 1163 | return 0; |
| 1164 | |
| 1165 | /* Dump shared memory only if mapped from an anonymous file. */ |
| 1166 | if (vma->vm_flags & VM_SHARED) |
| 1167 | return vma->vm_file->f_dentry->d_inode->i_nlink == 0; |
| 1168 | |
| 1169 | /* If it hasn't been written to, don't write it out */ |
| 1170 | if (!vma->anon_vma) |
| 1171 | return 0; |
| 1172 | |
| 1173 | return 1; |
| 1174 | } |
| 1175 | |
| 1176 | #define roundup(x, y) ((((x)+((y)-1))/(y))*(y)) |
| 1177 | |
| 1178 | /* An ELF note in memory */ |
| 1179 | struct memelfnote |
| 1180 | { |
| 1181 | const char *name; |
| 1182 | int type; |
| 1183 | unsigned int datasz; |
| 1184 | void *data; |
| 1185 | }; |
| 1186 | |
| 1187 | static int notesize(struct memelfnote *en) |
| 1188 | { |
| 1189 | int sz; |
| 1190 | |
| 1191 | sz = sizeof(struct elf_note); |
| 1192 | sz += roundup(strlen(en->name) + 1, 4); |
| 1193 | sz += roundup(en->datasz, 4); |
| 1194 | |
| 1195 | return sz; |
| 1196 | } |
| 1197 | |
| 1198 | #define DUMP_WRITE(addr, nr) \ |
| 1199 | do { if (!dump_write(file, (addr), (nr))) return 0; } while(0) |
| 1200 | #define DUMP_SEEK(off) \ |
| 1201 | do { if (!dump_seek(file, (off))) return 0; } while(0) |
| 1202 | |
| 1203 | static int writenote(struct memelfnote *men, struct file *file) |
| 1204 | { |
| 1205 | struct elf_note en; |
| 1206 | |
| 1207 | en.n_namesz = strlen(men->name) + 1; |
| 1208 | en.n_descsz = men->datasz; |
| 1209 | en.n_type = men->type; |
| 1210 | |
| 1211 | DUMP_WRITE(&en, sizeof(en)); |
| 1212 | DUMP_WRITE(men->name, en.n_namesz); |
| 1213 | /* XXX - cast from long long to long to avoid need for libgcc.a */ |
| 1214 | DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */ |
| 1215 | DUMP_WRITE(men->data, men->datasz); |
| 1216 | DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */ |
| 1217 | |
| 1218 | return 1; |
| 1219 | } |
| 1220 | #undef DUMP_WRITE |
| 1221 | #undef DUMP_SEEK |
| 1222 | |
| 1223 | #define DUMP_WRITE(addr, nr) \ |
| 1224 | if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \ |
| 1225 | goto end_coredump; |
| 1226 | #define DUMP_SEEK(off) \ |
| 1227 | if (!dump_seek(file, (off))) \ |
| 1228 | goto end_coredump; |
| 1229 | |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 1230 | static void fill_elf_header(struct elfhdr *elf, int segs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1231 | { |
| 1232 | memcpy(elf->e_ident, ELFMAG, SELFMAG); |
| 1233 | elf->e_ident[EI_CLASS] = ELF_CLASS; |
| 1234 | elf->e_ident[EI_DATA] = ELF_DATA; |
| 1235 | elf->e_ident[EI_VERSION] = EV_CURRENT; |
| 1236 | elf->e_ident[EI_OSABI] = ELF_OSABI; |
| 1237 | memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); |
| 1238 | |
| 1239 | elf->e_type = ET_CORE; |
| 1240 | elf->e_machine = ELF_ARCH; |
| 1241 | elf->e_version = EV_CURRENT; |
| 1242 | elf->e_entry = 0; |
| 1243 | elf->e_phoff = sizeof(struct elfhdr); |
| 1244 | elf->e_shoff = 0; |
| 1245 | elf->e_flags = ELF_CORE_EFLAGS; |
| 1246 | elf->e_ehsize = sizeof(struct elfhdr); |
| 1247 | elf->e_phentsize = sizeof(struct elf_phdr); |
| 1248 | elf->e_phnum = segs; |
| 1249 | elf->e_shentsize = 0; |
| 1250 | elf->e_shnum = 0; |
| 1251 | elf->e_shstrndx = 0; |
| 1252 | return; |
| 1253 | } |
| 1254 | |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 1255 | static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, off_t offset) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1256 | { |
| 1257 | phdr->p_type = PT_NOTE; |
| 1258 | phdr->p_offset = offset; |
| 1259 | phdr->p_vaddr = 0; |
| 1260 | phdr->p_paddr = 0; |
| 1261 | phdr->p_filesz = sz; |
| 1262 | phdr->p_memsz = 0; |
| 1263 | phdr->p_flags = 0; |
| 1264 | phdr->p_align = 0; |
| 1265 | return; |
| 1266 | } |
| 1267 | |
| 1268 | static void fill_note(struct memelfnote *note, const char *name, int type, |
| 1269 | unsigned int sz, void *data) |
| 1270 | { |
| 1271 | note->name = name; |
| 1272 | note->type = type; |
| 1273 | note->datasz = sz; |
| 1274 | note->data = data; |
| 1275 | return; |
| 1276 | } |
| 1277 | |
| 1278 | /* |
| 1279 | * fill up all the fields in prstatus from the given task struct, except registers |
| 1280 | * which need to be filled up separately. |
| 1281 | */ |
| 1282 | static void fill_prstatus(struct elf_prstatus *prstatus, |
| 1283 | struct task_struct *p, long signr) |
| 1284 | { |
| 1285 | prstatus->pr_info.si_signo = prstatus->pr_cursig = signr; |
| 1286 | prstatus->pr_sigpend = p->pending.signal.sig[0]; |
| 1287 | prstatus->pr_sighold = p->blocked.sig[0]; |
| 1288 | prstatus->pr_pid = p->pid; |
| 1289 | prstatus->pr_ppid = p->parent->pid; |
| 1290 | prstatus->pr_pgrp = process_group(p); |
| 1291 | prstatus->pr_sid = p->signal->session; |
| 1292 | if (thread_group_leader(p)) { |
| 1293 | /* |
| 1294 | * This is the record for the group leader. Add in the |
| 1295 | * cumulative times of previous dead threads. This total |
| 1296 | * won't include the time of each live thread whose state |
| 1297 | * is included in the core dump. The final total reported |
| 1298 | * to our parent process when it calls wait4 will include |
| 1299 | * those sums as well as the little bit more time it takes |
| 1300 | * this and each other thread to finish dying after the |
| 1301 | * core dump synchronization phase. |
| 1302 | */ |
| 1303 | cputime_to_timeval(cputime_add(p->utime, p->signal->utime), |
| 1304 | &prstatus->pr_utime); |
| 1305 | cputime_to_timeval(cputime_add(p->stime, p->signal->stime), |
| 1306 | &prstatus->pr_stime); |
| 1307 | } else { |
| 1308 | cputime_to_timeval(p->utime, &prstatus->pr_utime); |
| 1309 | cputime_to_timeval(p->stime, &prstatus->pr_stime); |
| 1310 | } |
| 1311 | cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime); |
| 1312 | cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime); |
| 1313 | } |
| 1314 | |
| 1315 | static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, |
| 1316 | struct mm_struct *mm) |
| 1317 | { |
Greg Kroah-Hartman | a84a505 | 2005-05-11 00:10:44 -0700 | [diff] [blame] | 1318 | unsigned int i, len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1319 | |
| 1320 | /* first copy the parameters from user space */ |
| 1321 | memset(psinfo, 0, sizeof(struct elf_prpsinfo)); |
| 1322 | |
| 1323 | len = mm->arg_end - mm->arg_start; |
| 1324 | if (len >= ELF_PRARGSZ) |
| 1325 | len = ELF_PRARGSZ-1; |
| 1326 | if (copy_from_user(&psinfo->pr_psargs, |
| 1327 | (const char __user *)mm->arg_start, len)) |
| 1328 | return -EFAULT; |
| 1329 | for(i = 0; i < len; i++) |
| 1330 | if (psinfo->pr_psargs[i] == 0) |
| 1331 | psinfo->pr_psargs[i] = ' '; |
| 1332 | psinfo->pr_psargs[len] = 0; |
| 1333 | |
| 1334 | psinfo->pr_pid = p->pid; |
| 1335 | psinfo->pr_ppid = p->parent->pid; |
| 1336 | psinfo->pr_pgrp = process_group(p); |
| 1337 | psinfo->pr_sid = p->signal->session; |
| 1338 | |
| 1339 | i = p->state ? ffz(~p->state) + 1 : 0; |
| 1340 | psinfo->pr_state = i; |
Carsten Otte | 5514854 | 2006-03-25 03:08:22 -0800 | [diff] [blame] | 1341 | psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1342 | psinfo->pr_zomb = psinfo->pr_sname == 'Z'; |
| 1343 | psinfo->pr_nice = task_nice(p); |
| 1344 | psinfo->pr_flag = p->flags; |
| 1345 | SET_UID(psinfo->pr_uid, p->uid); |
| 1346 | SET_GID(psinfo->pr_gid, p->gid); |
| 1347 | strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); |
| 1348 | |
| 1349 | return 0; |
| 1350 | } |
| 1351 | |
| 1352 | /* Here is the structure in which status of each thread is captured. */ |
| 1353 | struct elf_thread_status |
| 1354 | { |
| 1355 | struct list_head list; |
| 1356 | struct elf_prstatus prstatus; /* NT_PRSTATUS */ |
| 1357 | elf_fpregset_t fpu; /* NT_PRFPREG */ |
| 1358 | struct task_struct *thread; |
| 1359 | #ifdef ELF_CORE_COPY_XFPREGS |
| 1360 | elf_fpxregset_t xfpu; /* NT_PRXFPREG */ |
| 1361 | #endif |
| 1362 | struct memelfnote notes[3]; |
| 1363 | int num_notes; |
| 1364 | }; |
| 1365 | |
| 1366 | /* |
| 1367 | * In order to add the specific thread information for the elf file format, |
| 1368 | * we need to keep a linked list of every threads pr_status and then |
| 1369 | * create a single section for them in the final core file. |
| 1370 | */ |
| 1371 | static int elf_dump_thread_status(long signr, struct elf_thread_status *t) |
| 1372 | { |
| 1373 | int sz = 0; |
| 1374 | struct task_struct *p = t->thread; |
| 1375 | t->num_notes = 0; |
| 1376 | |
| 1377 | fill_prstatus(&t->prstatus, p, signr); |
| 1378 | elf_core_copy_task_regs(p, &t->prstatus.pr_reg); |
| 1379 | |
| 1380 | fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), &(t->prstatus)); |
| 1381 | t->num_notes++; |
| 1382 | sz += notesize(&t->notes[0]); |
| 1383 | |
| 1384 | if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, &t->fpu))) { |
| 1385 | fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), &(t->fpu)); |
| 1386 | t->num_notes++; |
| 1387 | sz += notesize(&t->notes[1]); |
| 1388 | } |
| 1389 | |
| 1390 | #ifdef ELF_CORE_COPY_XFPREGS |
| 1391 | if (elf_core_copy_task_xfpregs(p, &t->xfpu)) { |
| 1392 | fill_note(&t->notes[2], "LINUX", NT_PRXFPREG, sizeof(t->xfpu), &t->xfpu); |
| 1393 | t->num_notes++; |
| 1394 | sz += notesize(&t->notes[2]); |
| 1395 | } |
| 1396 | #endif |
| 1397 | return sz; |
| 1398 | } |
| 1399 | |
| 1400 | /* |
| 1401 | * Actual dumper |
| 1402 | * |
| 1403 | * This is a two-pass process; first we find the offsets of the bits, |
| 1404 | * and then they are actually written out. If we run out of core limit |
| 1405 | * we just truncate. |
| 1406 | */ |
| 1407 | static int elf_core_dump(long signr, struct pt_regs * regs, struct file * file) |
| 1408 | { |
| 1409 | #define NUM_NOTES 6 |
| 1410 | int has_dumped = 0; |
| 1411 | mm_segment_t fs; |
| 1412 | int segs; |
| 1413 | size_t size = 0; |
| 1414 | int i; |
| 1415 | struct vm_area_struct *vma; |
| 1416 | struct elfhdr *elf = NULL; |
| 1417 | off_t offset = 0, dataoff; |
| 1418 | unsigned long limit = current->signal->rlim[RLIMIT_CORE].rlim_cur; |
| 1419 | int numnote; |
| 1420 | struct memelfnote *notes = NULL; |
| 1421 | struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */ |
| 1422 | struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */ |
| 1423 | struct task_struct *g, *p; |
| 1424 | LIST_HEAD(thread_list); |
| 1425 | struct list_head *t; |
| 1426 | elf_fpregset_t *fpu = NULL; |
| 1427 | #ifdef ELF_CORE_COPY_XFPREGS |
| 1428 | elf_fpxregset_t *xfpu = NULL; |
| 1429 | #endif |
| 1430 | int thread_status_size = 0; |
| 1431 | elf_addr_t *auxv; |
| 1432 | |
| 1433 | /* |
| 1434 | * We no longer stop all VM operations. |
| 1435 | * |
| 1436 | * This is because those proceses that could possibly change map_count or |
| 1437 | * the mmap / vma pages are now blocked in do_exit on current finishing |
| 1438 | * this core dump. |
| 1439 | * |
| 1440 | * Only ptrace can touch these memory addresses, but it doesn't change |
| 1441 | * the map_count or the pages allocated. So no possibility of crashing |
| 1442 | * exists while dumping the mm->vm_next areas to the core file. |
| 1443 | */ |
| 1444 | |
| 1445 | /* alloc memory for large data structures: too large to be on stack */ |
| 1446 | elf = kmalloc(sizeof(*elf), GFP_KERNEL); |
| 1447 | if (!elf) |
| 1448 | goto cleanup; |
| 1449 | prstatus = kmalloc(sizeof(*prstatus), GFP_KERNEL); |
| 1450 | if (!prstatus) |
| 1451 | goto cleanup; |
| 1452 | psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL); |
| 1453 | if (!psinfo) |
| 1454 | goto cleanup; |
| 1455 | notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL); |
| 1456 | if (!notes) |
| 1457 | goto cleanup; |
| 1458 | fpu = kmalloc(sizeof(*fpu), GFP_KERNEL); |
| 1459 | if (!fpu) |
| 1460 | goto cleanup; |
| 1461 | #ifdef ELF_CORE_COPY_XFPREGS |
| 1462 | xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL); |
| 1463 | if (!xfpu) |
| 1464 | goto cleanup; |
| 1465 | #endif |
| 1466 | |
| 1467 | if (signr) { |
| 1468 | struct elf_thread_status *tmp; |
| 1469 | read_lock(&tasklist_lock); |
| 1470 | do_each_thread(g,p) |
| 1471 | if (current->mm == p->mm && current != p) { |
Oliver Neukum | 11b0b5a | 2006-03-25 03:08:13 -0800 | [diff] [blame] | 1472 | tmp = kzalloc(sizeof(*tmp), GFP_ATOMIC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1473 | if (!tmp) { |
| 1474 | read_unlock(&tasklist_lock); |
| 1475 | goto cleanup; |
| 1476 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1477 | INIT_LIST_HEAD(&tmp->list); |
| 1478 | tmp->thread = p; |
| 1479 | list_add(&tmp->list, &thread_list); |
| 1480 | } |
| 1481 | while_each_thread(g,p); |
| 1482 | read_unlock(&tasklist_lock); |
| 1483 | list_for_each(t, &thread_list) { |
| 1484 | struct elf_thread_status *tmp; |
| 1485 | int sz; |
| 1486 | |
| 1487 | tmp = list_entry(t, struct elf_thread_status, list); |
| 1488 | sz = elf_dump_thread_status(signr, tmp); |
| 1489 | thread_status_size += sz; |
| 1490 | } |
| 1491 | } |
| 1492 | /* now collect the dump for the current */ |
| 1493 | memset(prstatus, 0, sizeof(*prstatus)); |
| 1494 | fill_prstatus(prstatus, current, signr); |
| 1495 | elf_core_copy_regs(&prstatus->pr_reg, regs); |
| 1496 | |
| 1497 | segs = current->mm->map_count; |
| 1498 | #ifdef ELF_CORE_EXTRA_PHDRS |
| 1499 | segs += ELF_CORE_EXTRA_PHDRS; |
| 1500 | #endif |
| 1501 | |
| 1502 | /* Set up header */ |
| 1503 | fill_elf_header(elf, segs+1); /* including notes section */ |
| 1504 | |
| 1505 | has_dumped = 1; |
| 1506 | current->flags |= PF_DUMPCORE; |
| 1507 | |
| 1508 | /* |
| 1509 | * Set up the notes in similar form to SVR4 core dumps made |
| 1510 | * with info from their /proc. |
| 1511 | */ |
| 1512 | |
| 1513 | fill_note(notes +0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus); |
| 1514 | |
| 1515 | fill_psinfo(psinfo, current->group_leader, current->mm); |
| 1516 | fill_note(notes +1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo); |
| 1517 | |
Eric W. Biederman | a928972 | 2005-10-30 15:02:08 -0800 | [diff] [blame] | 1518 | numnote = 2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1519 | |
| 1520 | auxv = (elf_addr_t *) current->mm->saved_auxv; |
| 1521 | |
| 1522 | i = 0; |
| 1523 | do |
| 1524 | i += 2; |
| 1525 | while (auxv[i - 2] != AT_NULL); |
| 1526 | fill_note(¬es[numnote++], "CORE", NT_AUXV, |
| 1527 | i * sizeof (elf_addr_t), auxv); |
| 1528 | |
| 1529 | /* Try to dump the FPU. */ |
| 1530 | if ((prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs, fpu))) |
| 1531 | fill_note(notes + numnote++, |
| 1532 | "CORE", NT_PRFPREG, sizeof(*fpu), fpu); |
| 1533 | #ifdef ELF_CORE_COPY_XFPREGS |
| 1534 | if (elf_core_copy_task_xfpregs(current, xfpu)) |
| 1535 | fill_note(notes + numnote++, |
| 1536 | "LINUX", NT_PRXFPREG, sizeof(*xfpu), xfpu); |
| 1537 | #endif |
| 1538 | |
| 1539 | fs = get_fs(); |
| 1540 | set_fs(KERNEL_DS); |
| 1541 | |
| 1542 | DUMP_WRITE(elf, sizeof(*elf)); |
| 1543 | offset += sizeof(*elf); /* Elf header */ |
| 1544 | offset += (segs+1) * sizeof(struct elf_phdr); /* Program headers */ |
| 1545 | |
| 1546 | /* Write notes phdr entry */ |
| 1547 | { |
| 1548 | struct elf_phdr phdr; |
| 1549 | int sz = 0; |
| 1550 | |
| 1551 | for (i = 0; i < numnote; i++) |
| 1552 | sz += notesize(notes + i); |
| 1553 | |
| 1554 | sz += thread_status_size; |
| 1555 | |
| 1556 | fill_elf_note_phdr(&phdr, sz, offset); |
| 1557 | offset += sz; |
| 1558 | DUMP_WRITE(&phdr, sizeof(phdr)); |
| 1559 | } |
| 1560 | |
| 1561 | /* Page-align dumped data */ |
| 1562 | dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); |
| 1563 | |
| 1564 | /* Write program headers for segments dump */ |
| 1565 | for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) { |
| 1566 | struct elf_phdr phdr; |
| 1567 | size_t sz; |
| 1568 | |
| 1569 | sz = vma->vm_end - vma->vm_start; |
| 1570 | |
| 1571 | phdr.p_type = PT_LOAD; |
| 1572 | phdr.p_offset = offset; |
| 1573 | phdr.p_vaddr = vma->vm_start; |
| 1574 | phdr.p_paddr = 0; |
| 1575 | phdr.p_filesz = maydump(vma) ? sz : 0; |
| 1576 | phdr.p_memsz = sz; |
| 1577 | offset += phdr.p_filesz; |
| 1578 | phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0; |
| 1579 | if (vma->vm_flags & VM_WRITE) phdr.p_flags |= PF_W; |
| 1580 | if (vma->vm_flags & VM_EXEC) phdr.p_flags |= PF_X; |
| 1581 | phdr.p_align = ELF_EXEC_PAGESIZE; |
| 1582 | |
| 1583 | DUMP_WRITE(&phdr, sizeof(phdr)); |
| 1584 | } |
| 1585 | |
| 1586 | #ifdef ELF_CORE_WRITE_EXTRA_PHDRS |
| 1587 | ELF_CORE_WRITE_EXTRA_PHDRS; |
| 1588 | #endif |
| 1589 | |
| 1590 | /* write out the notes section */ |
| 1591 | for (i = 0; i < numnote; i++) |
| 1592 | if (!writenote(notes + i, file)) |
| 1593 | goto end_coredump; |
| 1594 | |
| 1595 | /* write out the thread status notes section */ |
| 1596 | list_for_each(t, &thread_list) { |
| 1597 | struct elf_thread_status *tmp = list_entry(t, struct elf_thread_status, list); |
| 1598 | for (i = 0; i < tmp->num_notes; i++) |
| 1599 | if (!writenote(&tmp->notes[i], file)) |
| 1600 | goto end_coredump; |
| 1601 | } |
| 1602 | |
| 1603 | DUMP_SEEK(dataoff); |
| 1604 | |
| 1605 | for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) { |
| 1606 | unsigned long addr; |
| 1607 | |
| 1608 | if (!maydump(vma)) |
| 1609 | continue; |
| 1610 | |
| 1611 | for (addr = vma->vm_start; |
| 1612 | addr < vma->vm_end; |
| 1613 | addr += PAGE_SIZE) { |
| 1614 | struct page* page; |
| 1615 | struct vm_area_struct *vma; |
| 1616 | |
| 1617 | if (get_user_pages(current, current->mm, addr, 1, 0, 1, |
| 1618 | &page, &vma) <= 0) { |
| 1619 | DUMP_SEEK (file->f_pos + PAGE_SIZE); |
| 1620 | } else { |
| 1621 | if (page == ZERO_PAGE(addr)) { |
| 1622 | DUMP_SEEK (file->f_pos + PAGE_SIZE); |
| 1623 | } else { |
| 1624 | void *kaddr; |
| 1625 | flush_cache_page(vma, addr, page_to_pfn(page)); |
| 1626 | kaddr = kmap(page); |
| 1627 | if ((size += PAGE_SIZE) > limit || |
| 1628 | !dump_write(file, kaddr, |
| 1629 | PAGE_SIZE)) { |
| 1630 | kunmap(page); |
| 1631 | page_cache_release(page); |
| 1632 | goto end_coredump; |
| 1633 | } |
| 1634 | kunmap(page); |
| 1635 | } |
| 1636 | page_cache_release(page); |
| 1637 | } |
| 1638 | } |
| 1639 | } |
| 1640 | |
| 1641 | #ifdef ELF_CORE_WRITE_EXTRA_DATA |
| 1642 | ELF_CORE_WRITE_EXTRA_DATA; |
| 1643 | #endif |
| 1644 | |
Jesper Juhl | 74da6cd | 2006-01-11 01:51:26 +0100 | [diff] [blame] | 1645 | if ((off_t)file->f_pos != offset) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1646 | /* Sanity check */ |
Jesper Juhl | 74da6cd | 2006-01-11 01:51:26 +0100 | [diff] [blame] | 1647 | printk(KERN_WARNING "elf_core_dump: file->f_pos (%ld) != offset (%ld)\n", |
| 1648 | (off_t)file->f_pos, offset); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1649 | } |
| 1650 | |
| 1651 | end_coredump: |
| 1652 | set_fs(fs); |
| 1653 | |
| 1654 | cleanup: |
Jesper Juhl | 74da6cd | 2006-01-11 01:51:26 +0100 | [diff] [blame] | 1655 | while (!list_empty(&thread_list)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1656 | struct list_head *tmp = thread_list.next; |
| 1657 | list_del(tmp); |
| 1658 | kfree(list_entry(tmp, struct elf_thread_status, list)); |
| 1659 | } |
| 1660 | |
| 1661 | kfree(elf); |
| 1662 | kfree(prstatus); |
| 1663 | kfree(psinfo); |
| 1664 | kfree(notes); |
| 1665 | kfree(fpu); |
| 1666 | #ifdef ELF_CORE_COPY_XFPREGS |
| 1667 | kfree(xfpu); |
| 1668 | #endif |
| 1669 | return has_dumped; |
| 1670 | #undef NUM_NOTES |
| 1671 | } |
| 1672 | |
| 1673 | #endif /* USE_ELF_CORE_DUMP */ |
| 1674 | |
| 1675 | static int __init init_elf_binfmt(void) |
| 1676 | { |
| 1677 | return register_binfmt(&elf_format); |
| 1678 | } |
| 1679 | |
| 1680 | static void __exit exit_elf_binfmt(void) |
| 1681 | { |
| 1682 | /* Remove the COFF and ELF loaders. */ |
| 1683 | unregister_binfmt(&elf_format); |
| 1684 | } |
| 1685 | |
| 1686 | core_initcall(init_elf_binfmt); |
| 1687 | module_exit(exit_elf_binfmt); |
| 1688 | MODULE_LICENSE("GPL"); |