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ext4: Fix Kconfig typo for ext4dev
[linux-2.6/linux-2.6-openrd.git] / fs / binfmt_elf_fdpic.c
blob0e8367c546248987418191c6ab7b14c5be61bec9
1 /* binfmt_elf_fdpic.c: FDPIC ELF binary format
2 *
3 * Copyright (C) 2003, 2004, 2006 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 * Derived from binfmt_elf.c
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13 #include <linux/module.h>
14
15 #include <linux/fs.h>
16 #include <linux/stat.h>
17 #include <linux/sched.h>
18 #include <linux/mm.h>
19 #include <linux/mman.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/slab.h>
27 #include <linux/pagemap.h>
28 #include <linux/security.h>
29 #include <linux/highmem.h>
30 #include <linux/highuid.h>
31 #include <linux/personality.h>
32 #include <linux/ptrace.h>
33 #include <linux/init.h>
34 #include <linux/elf.h>
35 #include <linux/elf-fdpic.h>
36 #include <linux/elfcore.h>
37
38 #include <asm/uaccess.h>
39 #include <asm/param.h>
40 #include <asm/pgalloc.h>
41
42 typedef char *elf_caddr_t;
43
44 #if 0
45 #define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
46 #else
47 #define kdebug(fmt, ...) do {} while(0)
48 #endif
49
50 #if 0
51 #define kdcore(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
52 #else
53 #define kdcore(fmt, ...) do {} while(0)
54 #endif
55
56 MODULE_LICENSE("GPL");
57
58 static int load_elf_fdpic_binary(struct linux_binprm *, struct pt_regs *);
59 static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *, struct file *);
60 static int elf_fdpic_map_file(struct elf_fdpic_params *, struct file *,
61 struct mm_struct *, const char *);
62
63 static int create_elf_fdpic_tables(struct linux_binprm *, struct mm_struct *,
64 struct elf_fdpic_params *,
65 struct elf_fdpic_params *);
66
67 #ifndef CONFIG_MMU
68 static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *,
69 unsigned long *);
70 static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *,
71 struct file *,
72 struct mm_struct *);
73 #endif
74
75 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *,
76 struct file *, struct mm_struct *);
77
78 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
79 static int elf_fdpic_core_dump(long, struct pt_regs *, struct file *, unsigned long limit);
80 #endif
81
82 static struct linux_binfmt elf_fdpic_format = {
83 .module = THIS_MODULE,
84 .load_binary = load_elf_fdpic_binary,
85 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
86 .core_dump = elf_fdpic_core_dump,
87 #endif
88 .min_coredump = ELF_EXEC_PAGESIZE,
89 };
90
91 static int __init init_elf_fdpic_binfmt(void)
92 {
93 return register_binfmt(&elf_fdpic_format);
94 }
95
96 static void __exit exit_elf_fdpic_binfmt(void)
97 {
98 unregister_binfmt(&elf_fdpic_format);
99 }
100
101 core_initcall(init_elf_fdpic_binfmt);
102 module_exit(exit_elf_fdpic_binfmt);
103
104 static int is_elf_fdpic(struct elfhdr *hdr, struct file *file)
105 {
106 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0)
107 return 0;
108 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)
109 return 0;
110 if (!elf_check_arch(hdr) || !elf_check_fdpic(hdr))
111 return 0;
112 if (!file->f_op || !file->f_op->mmap)
113 return 0;
114 return 1;
115 }
116
117 /*****************************************************************************/
118 /*
119 * read the program headers table into memory
120 */
121 static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params,
122 struct file *file)
123 {
124 struct elf32_phdr *phdr;
125 unsigned long size;
126 int retval, loop;
127
128 if (params->hdr.e_phentsize != sizeof(struct elf_phdr))
129 return -ENOMEM;
130 if (params->hdr.e_phnum > 65536U / sizeof(struct elf_phdr))
131 return -ENOMEM;
132
133 size = params->hdr.e_phnum * sizeof(struct elf_phdr);
134 params->phdrs = kmalloc(size, GFP_KERNEL);
135 if (!params->phdrs)
136 return -ENOMEM;
137
138 retval = kernel_read(file, params->hdr.e_phoff,
139 (char *) params->phdrs, size);
140 if (unlikely(retval != size))
141 return retval < 0 ? retval : -ENOEXEC;
142
143 /* determine stack size for this binary */
144 phdr = params->phdrs;
145 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
146 if (phdr->p_type != PT_GNU_STACK)
147 continue;
148
149 if (phdr->p_flags & PF_X)
150 params->flags |= ELF_FDPIC_FLAG_EXEC_STACK;
151 else
152 params->flags |= ELF_FDPIC_FLAG_NOEXEC_STACK;
153
154 params->stack_size = phdr->p_memsz;
155 break;
156 }
157
158 return 0;
159 }
160
161 /*****************************************************************************/
162 /*
163 * load an fdpic binary into various bits of memory
164 */
165 static int load_elf_fdpic_binary(struct linux_binprm *bprm,
166 struct pt_regs *regs)
167 {
168 struct elf_fdpic_params exec_params, interp_params;
169 struct elf_phdr *phdr;
170 unsigned long stack_size, entryaddr;
171 #ifndef CONFIG_MMU
172 unsigned long fullsize;
173 #endif
174 #ifdef ELF_FDPIC_PLAT_INIT
175 unsigned long dynaddr;
176 #endif
177 struct file *interpreter = NULL; /* to shut gcc up */
178 char *interpreter_name = NULL;
179 int executable_stack;
180 int retval, i;
181
182 kdebug("____ LOAD %d ____", current->pid);
183
184 memset(&exec_params, 0, sizeof(exec_params));
185 memset(&interp_params, 0, sizeof(interp_params));
186
187 exec_params.hdr = *(struct elfhdr *) bprm->buf;
188 exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE;
189
190 /* check that this is a binary we know how to deal with */
191 retval = -ENOEXEC;
192 if (!is_elf_fdpic(&exec_params.hdr, bprm->file))
193 goto error;
194
195 /* read the program header table */
196 retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);
197 if (retval < 0)
198 goto error;
199
200 /* scan for a program header that specifies an interpreter */
201 phdr = exec_params.phdrs;
202
203 for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) {
204 switch (phdr->p_type) {
205 case PT_INTERP:
206 retval = -ENOMEM;
207 if (phdr->p_filesz > PATH_MAX)
208 goto error;
209 retval = -ENOENT;
210 if (phdr->p_filesz < 2)
211 goto error;
212
213 /* read the name of the interpreter into memory */
214 interpreter_name = kmalloc(phdr->p_filesz, GFP_KERNEL);
215 if (!interpreter_name)
216 goto error;
217
218 retval = kernel_read(bprm->file,
219 phdr->p_offset,
220 interpreter_name,
221 phdr->p_filesz);
222 if (unlikely(retval != phdr->p_filesz)) {
223 if (retval >= 0)
224 retval = -ENOEXEC;
225 goto error;
226 }
227
228 retval = -ENOENT;
229 if (interpreter_name[phdr->p_filesz - 1] != '\0')
230 goto error;
231
232 kdebug("Using ELF interpreter %s", interpreter_name);
233
234 /* replace the program with the interpreter */
235 interpreter = open_exec(interpreter_name);
236 retval = PTR_ERR(interpreter);
237 if (IS_ERR(interpreter)) {
238 interpreter = NULL;
239 goto error;
240 }
241
242 /*
243 * If the binary is not readable then enforce
244 * mm->dumpable = 0 regardless of the interpreter's
245 * permissions.
246 */
247 if (file_permission(interpreter, MAY_READ) < 0)
248 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
249
250 retval = kernel_read(interpreter, 0, bprm->buf,
251 BINPRM_BUF_SIZE);
252 if (unlikely(retval != BINPRM_BUF_SIZE)) {
253 if (retval >= 0)
254 retval = -ENOEXEC;
255 goto error;
256 }
257
258 interp_params.hdr = *((struct elfhdr *) bprm->buf);
259 break;
260
261 case PT_LOAD:
262 #ifdef CONFIG_MMU
263 if (exec_params.load_addr == 0)
264 exec_params.load_addr = phdr->p_vaddr;
265 #endif
266 break;
267 }
268
269 }
270
271 if (elf_check_const_displacement(&exec_params.hdr))
272 exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
273
274 /* perform insanity checks on the interpreter */
275 if (interpreter_name) {
276 retval = -ELIBBAD;
277 if (!is_elf_fdpic(&interp_params.hdr, interpreter))
278 goto error;
279
280 interp_params.flags = ELF_FDPIC_FLAG_PRESENT;
281
282 /* read the interpreter's program header table */
283 retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter);
284 if (retval < 0)
285 goto error;
286 }
287
288 stack_size = exec_params.stack_size;
289 if (stack_size < interp_params.stack_size)
290 stack_size = interp_params.stack_size;
291
292 if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
293 executable_stack = EXSTACK_ENABLE_X;
294 else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
295 executable_stack = EXSTACK_DISABLE_X;
296 else if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
297 executable_stack = EXSTACK_ENABLE_X;
298 else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
299 executable_stack = EXSTACK_DISABLE_X;
300 else
301 executable_stack = EXSTACK_DEFAULT;
302
303 retval = -ENOEXEC;
304 if (stack_size == 0)
305 goto error;
306
307 if (elf_check_const_displacement(&interp_params.hdr))
308 interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
309
310 /* flush all traces of the currently running executable */
311 retval = flush_old_exec(bprm);
312 if (retval)
313 goto error;
314
315 /* there's now no turning back... the old userspace image is dead,
316 * defunct, deceased, etc. after this point we have to exit via
317 * error_kill */
318 set_personality(PER_LINUX_FDPIC);
319 set_binfmt(&elf_fdpic_format);
320
321 current->mm->start_code = 0;
322 current->mm->end_code = 0;
323 current->mm->start_stack = 0;
324 current->mm->start_data = 0;
325 current->mm->end_data = 0;
326 current->mm->context.exec_fdpic_loadmap = 0;
327 current->mm->context.interp_fdpic_loadmap = 0;
328
329 current->flags &= ~PF_FORKNOEXEC;
330
331 #ifdef CONFIG_MMU
332 elf_fdpic_arch_lay_out_mm(&exec_params,
333 &interp_params,
334 &current->mm->start_stack,
335 &current->mm->start_brk);
336
337 retval = setup_arg_pages(bprm, current->mm->start_stack,
338 executable_stack);
339 if (retval < 0) {
340 send_sig(SIGKILL, current, 0);
341 goto error_kill;
342 }
343 #endif
344
345 /* load the executable and interpreter into memory */
346 retval = elf_fdpic_map_file(&exec_params, bprm->file, current->mm,
347 "executable");
348 if (retval < 0)
349 goto error_kill;
350
351 if (interpreter_name) {
352 retval = elf_fdpic_map_file(&interp_params, interpreter,
353 current->mm, "interpreter");
354 if (retval < 0) {
355 printk(KERN_ERR "Unable to load interpreter\n");
356 goto error_kill;
357 }
358
359 allow_write_access(interpreter);
360 fput(interpreter);
361 interpreter = NULL;
362 }
363
364 #ifdef CONFIG_MMU
365 if (!current->mm->start_brk)
366 current->mm->start_brk = current->mm->end_data;
367
368 current->mm->brk = current->mm->start_brk =
369 PAGE_ALIGN(current->mm->start_brk);
370
371 #else
372 /* create a stack and brk area big enough for everyone
373 * - the brk heap starts at the bottom and works up
374 * - the stack starts at the top and works down
375 */
376 stack_size = (stack_size + PAGE_SIZE - 1) & PAGE_MASK;
377 if (stack_size < PAGE_SIZE * 2)
378 stack_size = PAGE_SIZE * 2;
379
380 down_write(&current->mm->mmap_sem);
381 current->mm->start_brk = do_mmap(NULL, 0, stack_size,
382 PROT_READ | PROT_WRITE | PROT_EXEC,
383 MAP_PRIVATE | MAP_ANONYMOUS | MAP_GROWSDOWN,
384 0);
385
386 if (IS_ERR_VALUE(current->mm->start_brk)) {
387 up_write(&current->mm->mmap_sem);
388 retval = current->mm->start_brk;
389 current->mm->start_brk = 0;
390 goto error_kill;
391 }
392
393 /* expand the stack mapping to use up the entire allocation granule */
394 fullsize = kobjsize((char *) current->mm->start_brk);
395 if (!IS_ERR_VALUE(do_mremap(current->mm->start_brk, stack_size,
396 fullsize, 0, 0)))
397 stack_size = fullsize;
398 up_write(&current->mm->mmap_sem);
399
400 current->mm->brk = current->mm->start_brk;
401 current->mm->context.end_brk = current->mm->start_brk;
402 current->mm->context.end_brk +=
403 (stack_size > PAGE_SIZE) ? (stack_size - PAGE_SIZE) : 0;
404 current->mm->start_stack = current->mm->start_brk + stack_size;
405 #endif
406
407 compute_creds(bprm);
408 current->flags &= ~PF_FORKNOEXEC;
409 if (create_elf_fdpic_tables(bprm, current->mm,
410 &exec_params, &interp_params) < 0)
411 goto error_kill;
412
413 kdebug("- start_code %lx", current->mm->start_code);
414 kdebug("- end_code %lx", current->mm->end_code);
415 kdebug("- start_data %lx", current->mm->start_data);
416 kdebug("- end_data %lx", current->mm->end_data);
417 kdebug("- start_brk %lx", current->mm->start_brk);
418 kdebug("- brk %lx", current->mm->brk);
419 kdebug("- start_stack %lx", current->mm->start_stack);
420
421 #ifdef ELF_FDPIC_PLAT_INIT
422 /*
423 * The ABI may specify that certain registers be set up in special
424 * ways (on i386 %edx is the address of a DT_FINI function, for
425 * example. This macro performs whatever initialization to
426 * the regs structure is required.
427 */
428 dynaddr = interp_params.dynamic_addr ?: exec_params.dynamic_addr;
429 ELF_FDPIC_PLAT_INIT(regs, exec_params.map_addr, interp_params.map_addr,
430 dynaddr);
431 #endif
432
433 /* everything is now ready... get the userspace context ready to roll */
434 entryaddr = interp_params.entry_addr ?: exec_params.entry_addr;
435 start_thread(regs, entryaddr, current->mm->start_stack);
436
437 retval = 0;
438
439 error:
440 if (interpreter) {
441 allow_write_access(interpreter);
442 fput(interpreter);
443 }
444 kfree(interpreter_name);
445 kfree(exec_params.phdrs);
446 kfree(exec_params.loadmap);
447 kfree(interp_params.phdrs);
448 kfree(interp_params.loadmap);
449 return retval;
450
451 /* unrecoverable error - kill the process */
452 error_kill:
453 send_sig(SIGSEGV, current, 0);
454 goto error;
455
456 }
457
458 /*****************************************************************************/
459
460 #ifndef ELF_BASE_PLATFORM
461 /*
462 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
463 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
464 * will be copied to the user stack in the same manner as AT_PLATFORM.
465 */
466 #define ELF_BASE_PLATFORM NULL
467 #endif
468
469 /*
470 * present useful information to the program by shovelling it onto the new
471 * process's stack
472 */
473 static int create_elf_fdpic_tables(struct linux_binprm *bprm,
474 struct mm_struct *mm,
475 struct elf_fdpic_params *exec_params,
476 struct elf_fdpic_params *interp_params)
477 {
478 unsigned long sp, csp, nitems;
479 elf_caddr_t __user *argv, *envp;
480 size_t platform_len = 0, len;
481 char *k_platform, *k_base_platform;
482 char __user *u_platform, *u_base_platform, *p;
483 long hwcap;
484 int loop;
485 int nr; /* reset for each csp adjustment */
486
487 #ifdef CONFIG_MMU
488 /* In some cases (e.g. Hyper-Threading), we want to avoid L1 evictions
489 * by the processes running on the same package. One thing we can do is
490 * to shuffle the initial stack for them, so we give the architecture
491 * an opportunity to do so here.
492 */
493 sp = arch_align_stack(bprm->p);
494 #else
495 sp = mm->start_stack;
496
497 /* stack the program arguments and environment */
498 if (elf_fdpic_transfer_args_to_stack(bprm, &sp) < 0)
499 return -EFAULT;
500 #endif
501
502 hwcap = ELF_HWCAP;
503
504 /*
505 * If this architecture has a platform capability string, copy it
506 * to userspace. In some cases (Sparc), this info is impossible
507 * for userspace to get any other way, in others (i386) it is
508 * merely difficult.
509 */
510 k_platform = ELF_PLATFORM;
511 u_platform = NULL;
512
513 if (k_platform) {
514 platform_len = strlen(k_platform) + 1;
515 sp -= platform_len;
516 u_platform = (char __user *) sp;
517 if (__copy_to_user(u_platform, k_platform, platform_len) != 0)
518 return -EFAULT;
519 }
520
521 /*
522 * If this architecture has a "base" platform capability
523 * string, copy it to userspace.
524 */
525 k_base_platform = ELF_BASE_PLATFORM;
526 u_base_platform = NULL;
527
528 if (k_base_platform) {
529 platform_len = strlen(k_base_platform) + 1;
530 sp -= platform_len;
531 u_base_platform = (char __user *) sp;
532 if (__copy_to_user(u_base_platform, k_base_platform, platform_len) != 0)
533 return -EFAULT;
534 }
535
536 sp &= ~7UL;
537
538 /* stack the load map(s) */
539 len = sizeof(struct elf32_fdpic_loadmap);
540 len += sizeof(struct elf32_fdpic_loadseg) * exec_params->loadmap->nsegs;
541 sp = (sp - len) & ~7UL;
542 exec_params->map_addr = sp;
543
544 if (copy_to_user((void __user *) sp, exec_params->loadmap, len) != 0)
545 return -EFAULT;
546
547 current->mm->context.exec_fdpic_loadmap = (unsigned long) sp;
548
549 if (interp_params->loadmap) {
550 len = sizeof(struct elf32_fdpic_loadmap);
551 len += sizeof(struct elf32_fdpic_loadseg) *
552 interp_params->loadmap->nsegs;
553 sp = (sp - len) & ~7UL;
554 interp_params->map_addr = sp;
555
556 if (copy_to_user((void __user *) sp, interp_params->loadmap,
557 len) != 0)
558 return -EFAULT;
559
560 current->mm->context.interp_fdpic_loadmap = (unsigned long) sp;
561 }
562
563 /* force 16 byte _final_ alignment here for generality */
564 #define DLINFO_ITEMS 15
565
566 nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) +
567 (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH;
568
569 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD)
570 nitems++;
571
572 csp = sp;
573 sp -= nitems * 2 * sizeof(unsigned long);
574 sp -= (bprm->envc + 1) * sizeof(char *); /* envv[] */
575 sp -= (bprm->argc + 1) * sizeof(char *); /* argv[] */
576 sp -= 1 * sizeof(unsigned long); /* argc */
577
578 csp -= sp & 15UL;
579 sp -= sp & 15UL;
580
581 /* put the ELF interpreter info on the stack */
582 #define NEW_AUX_ENT(id, val) \
583 do { \
584 struct { unsigned long _id, _val; } __user *ent; \
585 \
586 ent = (void __user *) csp; \
587 __put_user((id), &ent[nr]._id); \
588 __put_user((val), &ent[nr]._val); \
589 nr++; \
590 } while (0)
591
592 nr = 0;
593 csp -= 2 * sizeof(unsigned long);
594 NEW_AUX_ENT(AT_NULL, 0);
595 if (k_platform) {
596 nr = 0;
597 csp -= 2 * sizeof(unsigned long);
598 NEW_AUX_ENT(AT_PLATFORM,
599 (elf_addr_t) (unsigned long) u_platform);
600 }
601
602 if (k_base_platform) {
603 nr = 0;
604 csp -= 2 * sizeof(unsigned long);
605 NEW_AUX_ENT(AT_BASE_PLATFORM,
606 (elf_addr_t) (unsigned long) u_base_platform);
607 }
608
609 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
610 nr = 0;
611 csp -= 2 * sizeof(unsigned long);
612 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
613 }
614
615 nr = 0;
616 csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long);
617 NEW_AUX_ENT(AT_HWCAP, hwcap);
618 NEW_AUX_ENT(AT_PAGESZ, PAGE_SIZE);
619 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
620 NEW_AUX_ENT(AT_PHDR, exec_params->ph_addr);
621 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
622 NEW_AUX_ENT(AT_PHNUM, exec_params->hdr.e_phnum);
623 NEW_AUX_ENT(AT_BASE, interp_params->elfhdr_addr);
624 NEW_AUX_ENT(AT_FLAGS, 0);
625 NEW_AUX_ENT(AT_ENTRY, exec_params->entry_addr);
626 NEW_AUX_ENT(AT_UID, (elf_addr_t) current->uid);
627 NEW_AUX_ENT(AT_EUID, (elf_addr_t) current->euid);
628 NEW_AUX_ENT(AT_GID, (elf_addr_t) current->gid);
629 NEW_AUX_ENT(AT_EGID, (elf_addr_t) current->egid);
630 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
631 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
632
633 #ifdef ARCH_DLINFO
634 nr = 0;
635 csp -= AT_VECTOR_SIZE_ARCH * 2 * sizeof(unsigned long);
636
637 /* ARCH_DLINFO must come last so platform specific code can enforce
638 * special alignment requirements on the AUXV if necessary (eg. PPC).
639 */
640 ARCH_DLINFO;
641 #endif
642 #undef NEW_AUX_ENT
643
644 /* allocate room for argv[] and envv[] */
645 csp -= (bprm->envc + 1) * sizeof(elf_caddr_t);
646 envp = (elf_caddr_t __user *) csp;
647 csp -= (bprm->argc + 1) * sizeof(elf_caddr_t);
648 argv = (elf_caddr_t __user *) csp;
649
650 /* stack argc */
651 csp -= sizeof(unsigned long);
652 __put_user(bprm->argc, (unsigned long __user *) csp);
653
654 BUG_ON(csp != sp);
655
656 /* fill in the argv[] array */
657 #ifdef CONFIG_MMU
658 current->mm->arg_start = bprm->p;
659 #else
660 current->mm->arg_start = current->mm->start_stack -
661 (MAX_ARG_PAGES * PAGE_SIZE - bprm->p);
662 #endif
663
664 p = (char __user *) current->mm->arg_start;
665 for (loop = bprm->argc; loop > 0; loop--) {
666 __put_user((elf_caddr_t) p, argv++);
667 len = strnlen_user(p, MAX_ARG_STRLEN);
668 if (!len || len > MAX_ARG_STRLEN)
669 return -EINVAL;
670 p += len;
671 }
672 __put_user(NULL, argv);
673 current->mm->arg_end = (unsigned long) p;
674
675 /* fill in the envv[] array */
676 current->mm->env_start = (unsigned long) p;
677 for (loop = bprm->envc; loop > 0; loop--) {
678 __put_user((elf_caddr_t)(unsigned long) p, envp++);
679 len = strnlen_user(p, MAX_ARG_STRLEN);
680 if (!len || len > MAX_ARG_STRLEN)
681 return -EINVAL;
682 p += len;
683 }
684 __put_user(NULL, envp);
685 current->mm->env_end = (unsigned long) p;
686
687 mm->start_stack = (unsigned long) sp;
688 return 0;
689 }
690
691 /*****************************************************************************/
692 /*
693 * transfer the program arguments and environment from the holding pages onto
694 * the stack
695 */
696 #ifndef CONFIG_MMU
697 static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *bprm,
698 unsigned long *_sp)
699 {
700 unsigned long index, stop, sp;
701 char *src;
702 int ret = 0;
703
704 stop = bprm->p >> PAGE_SHIFT;
705 sp = *_sp;
706
707 for (index = MAX_ARG_PAGES - 1; index >= stop; index--) {
708 src = kmap(bprm->page[index]);
709 sp -= PAGE_SIZE;
710 if (copy_to_user((void *) sp, src, PAGE_SIZE) != 0)
711 ret = -EFAULT;
712 kunmap(bprm->page[index]);
713 if (ret < 0)
714 goto out;
715 }
716
717 *_sp = (*_sp - (MAX_ARG_PAGES * PAGE_SIZE - bprm->p)) & ~15;
718
719 out:
720 return ret;
721 }
722 #endif
723
724 /*****************************************************************************/
725 /*
726 * load the appropriate binary image (executable or interpreter) into memory
727 * - we assume no MMU is available
728 * - if no other PIC bits are set in params->hdr->e_flags
729 * - we assume that the LOADable segments in the binary are independently relocatable
730 * - we assume R/O executable segments are shareable
731 * - else
732 * - we assume the loadable parts of the image to require fixed displacement
733 * - the image is not shareable
734 */
735 static int elf_fdpic_map_file(struct elf_fdpic_params *params,
736 struct file *file,
737 struct mm_struct *mm,
738 const char *what)
739 {
740 struct elf32_fdpic_loadmap *loadmap;
741 #ifdef CONFIG_MMU
742 struct elf32_fdpic_loadseg *mseg;
743 #endif
744 struct elf32_fdpic_loadseg *seg;
745 struct elf32_phdr *phdr;
746 unsigned long load_addr, stop;
747 unsigned nloads, tmp;
748 size_t size;
749 int loop, ret;
750
751 /* allocate a load map table */
752 nloads = 0;
753 for (loop = 0; loop < params->hdr.e_phnum; loop++)
754 if (params->phdrs[loop].p_type == PT_LOAD)
755 nloads++;
756
757 if (nloads == 0)
758 return -ELIBBAD;
759
760 size = sizeof(*loadmap) + nloads * sizeof(*seg);
761 loadmap = kzalloc(size, GFP_KERNEL);
762 if (!loadmap)
763 return -ENOMEM;
764
765 params->loadmap = loadmap;
766
767 loadmap->version = ELF32_FDPIC_LOADMAP_VERSION;
768 loadmap->nsegs = nloads;
769
770 load_addr = params->load_addr;
771 seg = loadmap->segs;
772
773 /* map the requested LOADs into the memory space */
774 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
775 case ELF_FDPIC_FLAG_CONSTDISP:
776 case ELF_FDPIC_FLAG_CONTIGUOUS:
777 #ifndef CONFIG_MMU
778 ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm);
779 if (ret < 0)
780 return ret;
781 break;
782 #endif
783 default:
784 ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm);
785 if (ret < 0)
786 return ret;
787 break;
788 }
789
790 /* map the entry point */
791 if (params->hdr.e_entry) {
792 seg = loadmap->segs;
793 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
794 if (params->hdr.e_entry >= seg->p_vaddr &&
795 params->hdr.e_entry < seg->p_vaddr + seg->p_memsz) {
796 params->entry_addr =
797 (params->hdr.e_entry - seg->p_vaddr) +
798 seg->addr;
799 break;
800 }
801 }
802 }
803
804 /* determine where the program header table has wound up if mapped */
805 stop = params->hdr.e_phoff;
806 stop += params->hdr.e_phnum * sizeof (struct elf_phdr);
807 phdr = params->phdrs;
808
809 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
810 if (phdr->p_type != PT_LOAD)
811 continue;
812
813 if (phdr->p_offset > params->hdr.e_phoff ||
814 phdr->p_offset + phdr->p_filesz < stop)
815 continue;
816
817 seg = loadmap->segs;
818 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
819 if (phdr->p_vaddr >= seg->p_vaddr &&
820 phdr->p_vaddr + phdr->p_filesz <=
821 seg->p_vaddr + seg->p_memsz) {
822 params->ph_addr =
823 (phdr->p_vaddr - seg->p_vaddr) +
824 seg->addr +
825 params->hdr.e_phoff - phdr->p_offset;
826 break;
827 }
828 }
829 break;
830 }
831
832 /* determine where the dynamic section has wound up if there is one */
833 phdr = params->phdrs;
834 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
835 if (phdr->p_type != PT_DYNAMIC)
836 continue;
837
838 seg = loadmap->segs;
839 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
840 if (phdr->p_vaddr >= seg->p_vaddr &&
841 phdr->p_vaddr + phdr->p_memsz <=
842 seg->p_vaddr + seg->p_memsz) {
843 params->dynamic_addr =
844 (phdr->p_vaddr - seg->p_vaddr) +
845 seg->addr;
846
847 /* check the dynamic section contains at least
848 * one item, and that the last item is a NULL
849 * entry */
850 if (phdr->p_memsz == 0 ||
851 phdr->p_memsz % sizeof(Elf32_Dyn) != 0)
852 goto dynamic_error;
853
854 tmp = phdr->p_memsz / sizeof(Elf32_Dyn);
855 if (((Elf32_Dyn *)
856 params->dynamic_addr)[tmp - 1].d_tag != 0)
857 goto dynamic_error;
858 break;
859 }
860 }
861 break;
862 }
863
864 /* now elide adjacent segments in the load map on MMU linux
865 * - on uClinux the holes between may actually be filled with system
866 * stuff or stuff from other processes
867 */
868 #ifdef CONFIG_MMU
869 nloads = loadmap->nsegs;
870 mseg = loadmap->segs;
871 seg = mseg + 1;
872 for (loop = 1; loop < nloads; loop++) {
873 /* see if we have a candidate for merging */
874 if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) {
875 load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz);
876 if (load_addr == (seg->addr & PAGE_MASK)) {
877 mseg->p_memsz +=
878 load_addr -
879 (mseg->addr + mseg->p_memsz);
880 mseg->p_memsz += seg->addr & ~PAGE_MASK;
881 mseg->p_memsz += seg->p_memsz;
882 loadmap->nsegs--;
883 continue;
884 }
885 }
886
887 mseg++;
888 if (mseg != seg)
889 *mseg = *seg;
890 }
891 #endif
892
893 kdebug("Mapped Object [%s]:", what);
894 kdebug("- elfhdr : %lx", params->elfhdr_addr);
895 kdebug("- entry : %lx", params->entry_addr);
896 kdebug("- PHDR[] : %lx", params->ph_addr);
897 kdebug("- DYNAMIC[]: %lx", params->dynamic_addr);
898 seg = loadmap->segs;
899 for (loop = 0; loop < loadmap->nsegs; loop++, seg++)
900 kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]",
901 loop,
902 seg->addr, seg->addr + seg->p_memsz - 1,
903 seg->p_vaddr, seg->p_memsz);
904
905 return 0;
906
907 dynamic_error:
908 printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n",
909 what, file->f_path.dentry->d_inode->i_ino);
910 return -ELIBBAD;
911 }
912
913 /*****************************************************************************/
914 /*
915 * map a file with constant displacement under uClinux
916 */
917 #ifndef CONFIG_MMU
918 static int elf_fdpic_map_file_constdisp_on_uclinux(
919 struct elf_fdpic_params *params,
920 struct file *file,
921 struct mm_struct *mm)
922 {
923 struct elf32_fdpic_loadseg *seg;
924 struct elf32_phdr *phdr;
925 unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags;
926 loff_t fpos;
927 int loop, ret;
928
929 load_addr = params->load_addr;
930 seg = params->loadmap->segs;
931
932 /* determine the bounds of the contiguous overall allocation we must
933 * make */
934 phdr = params->phdrs;
935 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
936 if (params->phdrs[loop].p_type != PT_LOAD)
937 continue;
938
939 if (base > phdr->p_vaddr)
940 base = phdr->p_vaddr;
941 if (top < phdr->p_vaddr + phdr->p_memsz)
942 top = phdr->p_vaddr + phdr->p_memsz;
943 }
944
945 /* allocate one big anon block for everything */
946 mflags = MAP_PRIVATE;
947 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
948 mflags |= MAP_EXECUTABLE;
949
950 down_write(&mm->mmap_sem);
951 maddr = do_mmap(NULL, load_addr, top - base,
952 PROT_READ | PROT_WRITE | PROT_EXEC, mflags, 0);
953 up_write(&mm->mmap_sem);
954 if (IS_ERR_VALUE(maddr))
955 return (int) maddr;
956
957 if (load_addr != 0)
958 load_addr += PAGE_ALIGN(top - base);
959
960 /* and then load the file segments into it */
961 phdr = params->phdrs;
962 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
963 if (params->phdrs[loop].p_type != PT_LOAD)
964 continue;
965
966 fpos = phdr->p_offset;
967
968 seg->addr = maddr + (phdr->p_vaddr - base);
969 seg->p_vaddr = phdr->p_vaddr;
970 seg->p_memsz = phdr->p_memsz;
971
972 ret = file->f_op->read(file, (void *) seg->addr,
973 phdr->p_filesz, &fpos);
974 if (ret < 0)
975 return ret;
976
977 /* map the ELF header address if in this segment */
978 if (phdr->p_offset == 0)
979 params->elfhdr_addr = seg->addr;
980
981 /* clear any space allocated but not loaded */
982 if (phdr->p_filesz < phdr->p_memsz)
983 clear_user((void *) (seg->addr + phdr->p_filesz),
984 phdr->p_memsz - phdr->p_filesz);
985
986 if (mm) {
987 if (phdr->p_flags & PF_X) {
988 if (!mm->start_code) {
989 mm->start_code = seg->addr;
990 mm->end_code = seg->addr +
991 phdr->p_memsz;
992 }
993 } else if (!mm->start_data) {
994 mm->start_data = seg->addr;
995 #ifndef CONFIG_MMU
996 mm->end_data = seg->addr + phdr->p_memsz;
997 #endif
998 }
999
1000 #ifdef CONFIG_MMU
1001 if (seg->addr + phdr->p_memsz > mm->end_data)
1002 mm->end_data = seg->addr + phdr->p_memsz;
1003 #endif
1004 }
1005
1006 seg++;
1007 }
1008
1009 return 0;
1010 }
1011 #endif
1012
1013 /*****************************************************************************/
1014 /*
1015 * map a binary by direct mmap() of the individual PT_LOAD segments
1016 */
1017 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
1018 struct file *file,
1019 struct mm_struct *mm)
1020 {
1021 struct elf32_fdpic_loadseg *seg;
1022 struct elf32_phdr *phdr;
1023 unsigned long load_addr, delta_vaddr;
1024 int loop, dvset;
1025
1026 load_addr = params->load_addr;
1027 delta_vaddr = 0;
1028 dvset = 0;
1029
1030 seg = params->loadmap->segs;
1031
1032 /* deal with each load segment separately */
1033 phdr = params->phdrs;
1034 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
1035 unsigned long maddr, disp, excess, excess1;
1036 int prot = 0, flags;
1037
1038 if (phdr->p_type != PT_LOAD)
1039 continue;
1040
1041 kdebug("[LOAD] va=%lx of=%lx fs=%lx ms=%lx",
1042 (unsigned long) phdr->p_vaddr,
1043 (unsigned long) phdr->p_offset,
1044 (unsigned long) phdr->p_filesz,
1045 (unsigned long) phdr->p_memsz);
1046
1047 /* determine the mapping parameters */
1048 if (phdr->p_flags & PF_R) prot |= PROT_READ;
1049 if (phdr->p_flags & PF_W) prot |= PROT_WRITE;
1050 if (phdr->p_flags & PF_X) prot |= PROT_EXEC;
1051
1052 flags = MAP_PRIVATE | MAP_DENYWRITE;
1053 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
1054 flags |= MAP_EXECUTABLE;
1055
1056 maddr = 0;
1057
1058 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
1059 case ELF_FDPIC_FLAG_INDEPENDENT:
1060 /* PT_LOADs are independently locatable */
1061 break;
1062
1063 case ELF_FDPIC_FLAG_HONOURVADDR:
1064 /* the specified virtual address must be honoured */
1065 maddr = phdr->p_vaddr;
1066 flags |= MAP_FIXED;
1067 break;
1068
1069 case ELF_FDPIC_FLAG_CONSTDISP:
1070 /* constant displacement
1071 * - can be mapped anywhere, but must be mapped as a
1072 * unit
1073 */
1074 if (!dvset) {
1075 maddr = load_addr;
1076 delta_vaddr = phdr->p_vaddr;
1077 dvset = 1;
1078 } else {
1079 maddr = load_addr + phdr->p_vaddr - delta_vaddr;
1080 flags |= MAP_FIXED;
1081 }
1082 break;
1083
1084 case ELF_FDPIC_FLAG_CONTIGUOUS:
1085 /* contiguity handled later */
1086 break;
1087
1088 default:
1089 BUG();
1090 }
1091
1092 maddr &= PAGE_MASK;
1093
1094 /* create the mapping */
1095 disp = phdr->p_vaddr & ~PAGE_MASK;
1096 down_write(&mm->mmap_sem);
1097 maddr = do_mmap(file, maddr, phdr->p_memsz + disp, prot, flags,
1098 phdr->p_offset - disp);
1099 up_write(&mm->mmap_sem);
1100
1101 kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx",
1102 loop, phdr->p_memsz + disp, prot, flags,
1103 phdr->p_offset - disp, maddr);
1104
1105 if (IS_ERR_VALUE(maddr))
1106 return (int) maddr;
1107
1108 if ((params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) ==
1109 ELF_FDPIC_FLAG_CONTIGUOUS)
1110 load_addr += PAGE_ALIGN(phdr->p_memsz + disp);
1111
1112 seg->addr = maddr + disp;
1113 seg->p_vaddr = phdr->p_vaddr;
1114 seg->p_memsz = phdr->p_memsz;
1115
1116 /* map the ELF header address if in this segment */
1117 if (phdr->p_offset == 0)
1118 params->elfhdr_addr = seg->addr;
1119
1120 /* clear the bit between beginning of mapping and beginning of
1121 * PT_LOAD */
1122 if (prot & PROT_WRITE && disp > 0) {
1123 kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp);
1124 clear_user((void __user *) maddr, disp);
1125 maddr += disp;
1126 }
1127
1128 /* clear any space allocated but not loaded
1129 * - on uClinux we can just clear the lot
1130 * - on MMU linux we'll get a SIGBUS beyond the last page
1131 * extant in the file
1132 */
1133 excess = phdr->p_memsz - phdr->p_filesz;
1134 excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
1135
1136 #ifdef CONFIG_MMU
1137 if (excess > excess1) {
1138 unsigned long xaddr = maddr + phdr->p_filesz + excess1;
1139 unsigned long xmaddr;
1140
1141 flags |= MAP_FIXED | MAP_ANONYMOUS;
1142 down_write(&mm->mmap_sem);
1143 xmaddr = do_mmap(NULL, xaddr, excess - excess1,
1144 prot, flags, 0);
1145 up_write(&mm->mmap_sem);
1146
1147 kdebug("mmap[%d] <anon>"
1148 " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",
1149 loop, xaddr, excess - excess1, prot, flags,
1150 xmaddr);
1151
1152 if (xmaddr != xaddr)
1153 return -ENOMEM;
1154 }
1155
1156 if (prot & PROT_WRITE && excess1 > 0) {
1157 kdebug("clear[%d] ad=%lx sz=%lx",
1158 loop, maddr + phdr->p_filesz, excess1);
1159 clear_user((void __user *) maddr + phdr->p_filesz,
1160 excess1);
1161 }
1162
1163 #else
1164 if (excess > 0) {
1165 kdebug("clear[%d] ad=%lx sz=%lx",
1166 loop, maddr + phdr->p_filesz, excess);
1167 clear_user((void *) maddr + phdr->p_filesz, excess);
1168 }
1169 #endif
1170
1171 if (mm) {
1172 if (phdr->p_flags & PF_X) {
1173 if (!mm->start_code) {
1174 mm->start_code = maddr;
1175 mm->end_code = maddr + phdr->p_memsz;
1176 }
1177 } else if (!mm->start_data) {
1178 mm->start_data = maddr;
1179 mm->end_data = maddr + phdr->p_memsz;
1180 }
1181 }
1182
1183 seg++;
1184 }
1185
1186 return 0;
1187 }
1188
1189 /*****************************************************************************/
1190 /*
1191 * ELF-FDPIC core dumper
1192 *
1193 * Modelled on fs/exec.c:aout_core_dump()
1194 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1195 *
1196 * Modelled on fs/binfmt_elf.c core dumper
1197 */
1198 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
1199
1200 /*
1201 * These are the only things you should do on a core-file: use only these
1202 * functions to write out all the necessary info.
1203 */
1204 static int dump_write(struct file *file, const void *addr, int nr)
1205 {
1206 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
1207 }
1208
1209 static int dump_seek(struct file *file, loff_t off)
1210 {
1211 if (file->f_op->llseek) {
1212 if (file->f_op->llseek(file, off, SEEK_SET) != off)
1213 return 0;
1214 } else {
1215 file->f_pos = off;
1216 }
1217 return 1;
1218 }
1219
1220 /*
1221 * Decide whether a segment is worth dumping; default is yes to be
1222 * sure (missing info is worse than too much; etc).
1223 * Personally I'd include everything, and use the coredump limit...
1224 *
1225 * I think we should skip something. But I am not sure how. H.J.
1226 */
1227 static int maydump(struct vm_area_struct *vma, unsigned long mm_flags)
1228 {
1229 int dump_ok;
1230
1231 /* Do not dump I/O mapped devices or special mappings */
1232 if (vma->vm_flags & (VM_IO | VM_RESERVED)) {
1233 kdcore("%08lx: %08lx: no (IO)", vma->vm_start, vma->vm_flags);
1234 return 0;
1235 }
1236
1237 /* If we may not read the contents, don't allow us to dump
1238 * them either. "dump_write()" can't handle it anyway.
1239 */
1240 if (!(vma->vm_flags & VM_READ)) {
1241 kdcore("%08lx: %08lx: no (!read)", vma->vm_start, vma->vm_flags);
1242 return 0;
1243 }
1244
1245 /* By default, dump shared memory if mapped from an anonymous file. */
1246 if (vma->vm_flags & VM_SHARED) {
1247 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0) {
1248 dump_ok = test_bit(MMF_DUMP_ANON_SHARED, &mm_flags);
1249 kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
1250 vma->vm_flags, dump_ok ? "yes" : "no");
1251 return dump_ok;
1252 }
1253
1254 dump_ok = test_bit(MMF_DUMP_MAPPED_SHARED, &mm_flags);
1255 kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
1256 vma->vm_flags, dump_ok ? "yes" : "no");
1257 return dump_ok;
1258 }
1259
1260 #ifdef CONFIG_MMU
1261 /* By default, if it hasn't been written to, don't write it out */
1262 if (!vma->anon_vma) {
1263 dump_ok = test_bit(MMF_DUMP_MAPPED_PRIVATE, &mm_flags);
1264 kdcore("%08lx: %08lx: %s (!anon)", vma->vm_start,
1265 vma->vm_flags, dump_ok ? "yes" : "no");
1266 return dump_ok;
1267 }
1268 #endif
1269
1270 dump_ok = test_bit(MMF_DUMP_ANON_PRIVATE, &mm_flags);
1271 kdcore("%08lx: %08lx: %s", vma->vm_start, vma->vm_flags,
1272 dump_ok ? "yes" : "no");
1273 return dump_ok;
1274 }
1275
1276 /* An ELF note in memory */
1277 struct memelfnote
1278 {
1279 const char *name;
1280 int type;
1281 unsigned int datasz;
1282 void *data;
1283 };
1284
1285 static int notesize(struct memelfnote *en)
1286 {
1287 int sz;
1288
1289 sz = sizeof(struct elf_note);
1290 sz += roundup(strlen(en->name) + 1, 4);
1291 sz += roundup(en->datasz, 4);
1292
1293 return sz;
1294 }
1295
1296 /* #define DEBUG */
1297
1298 #define DUMP_WRITE(addr, nr) \
1299 do { if (!dump_write(file, (addr), (nr))) return 0; } while(0)
1300 #define DUMP_SEEK(off) \
1301 do { if (!dump_seek(file, (off))) return 0; } while(0)
1302
1303 static int writenote(struct memelfnote *men, struct file *file)
1304 {
1305 struct elf_note en;
1306
1307 en.n_namesz = strlen(men->name) + 1;
1308 en.n_descsz = men->datasz;
1309 en.n_type = men->type;
1310
1311 DUMP_WRITE(&en, sizeof(en));
1312 DUMP_WRITE(men->name, en.n_namesz);
1313 /* XXX - cast from long long to long to avoid need for libgcc.a */
1314 DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
1315 DUMP_WRITE(men->data, men->datasz);
1316 DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
1317
1318 return 1;
1319 }
1320 #undef DUMP_WRITE
1321 #undef DUMP_SEEK
1322
1323 #define DUMP_WRITE(addr, nr) \
1324 if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
1325 goto end_coredump;
1326 #define DUMP_SEEK(off) \
1327 if (!dump_seek(file, (off))) \
1328 goto end_coredump;
1329
1330 static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)
1331 {
1332 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1333 elf->e_ident[EI_CLASS] = ELF_CLASS;
1334 elf->e_ident[EI_DATA] = ELF_DATA;
1335 elf->e_ident[EI_VERSION] = EV_CURRENT;
1336 elf->e_ident[EI_OSABI] = ELF_OSABI;
1337 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
1338
1339 elf->e_type = ET_CORE;
1340 elf->e_machine = ELF_ARCH;
1341 elf->e_version = EV_CURRENT;
1342 elf->e_entry = 0;
1343 elf->e_phoff = sizeof(struct elfhdr);
1344 elf->e_shoff = 0;
1345 elf->e_flags = ELF_FDPIC_CORE_EFLAGS;
1346 elf->e_ehsize = sizeof(struct elfhdr);
1347 elf->e_phentsize = sizeof(struct elf_phdr);
1348 elf->e_phnum = segs;
1349 elf->e_shentsize = 0;
1350 elf->e_shnum = 0;
1351 elf->e_shstrndx = 0;
1352 return;
1353 }
1354
1355 static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
1356 {
1357 phdr->p_type = PT_NOTE;
1358 phdr->p_offset = offset;
1359 phdr->p_vaddr = 0;
1360 phdr->p_paddr = 0;
1361 phdr->p_filesz = sz;
1362 phdr->p_memsz = 0;
1363 phdr->p_flags = 0;
1364 phdr->p_align = 0;
1365 return;
1366 }
1367
1368 static inline void fill_note(struct memelfnote *note, const char *name, int type,
1369 unsigned int sz, void *data)
1370 {
1371 note->name = name;
1372 note->type = type;
1373 note->datasz = sz;
1374 note->data = data;
1375 return;
1376 }
1377
1378 /*
1379 * fill up all the fields in prstatus from the given task struct, except
1380 * registers which need to be filled up seperately.
1381 */
1382 static void fill_prstatus(struct elf_prstatus *prstatus,
1383 struct task_struct *p, long signr)
1384 {
1385 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1386 prstatus->pr_sigpend = p->pending.signal.sig[0];
1387 prstatus->pr_sighold = p->blocked.sig[0];
1388 prstatus->pr_pid = task_pid_vnr(p);
1389 prstatus->pr_ppid = task_pid_vnr(p->parent);
1390 prstatus->pr_pgrp = task_pgrp_vnr(p);
1391 prstatus->pr_sid = task_session_vnr(p);
1392 if (thread_group_leader(p)) {
1393 /*
1394 * This is the record for the group leader. Add in the
1395 * cumulative times of previous dead threads. This total
1396 * won't include the time of each live thread whose state
1397 * is included in the core dump. The final total reported
1398 * to our parent process when it calls wait4 will include
1399 * those sums as well as the little bit more time it takes
1400 * this and each other thread to finish dying after the
1401 * core dump synchronization phase.
1402 */
1403 cputime_to_timeval(cputime_add(p->utime, p->signal->utime),
1404 &prstatus->pr_utime);
1405 cputime_to_timeval(cputime_add(p->stime, p->signal->stime),
1406 &prstatus->pr_stime);
1407 } else {
1408 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1409 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1410 }
1411 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1412 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1413
1414 prstatus->pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap;
1415 prstatus->pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap;
1416 }
1417
1418 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1419 struct mm_struct *mm)
1420 {
1421 unsigned int i, len;
1422
1423 /* first copy the parameters from user space */
1424 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1425
1426 len = mm->arg_end - mm->arg_start;
1427 if (len >= ELF_PRARGSZ)
1428 len = ELF_PRARGSZ - 1;
1429 if (copy_from_user(&psinfo->pr_psargs,
1430 (const char __user *) mm->arg_start, len))
1431 return -EFAULT;
1432 for (i = 0; i < len; i++)
1433 if (psinfo->pr_psargs[i] == 0)
1434 psinfo->pr_psargs[i] = ' ';
1435 psinfo->pr_psargs[len] = 0;
1436
1437 psinfo->pr_pid = task_pid_vnr(p);
1438 psinfo->pr_ppid = task_pid_vnr(p->parent);
1439 psinfo->pr_pgrp = task_pgrp_vnr(p);
1440 psinfo->pr_sid = task_session_vnr(p);
1441
1442 i = p->state ? ffz(~p->state) + 1 : 0;
1443 psinfo->pr_state = i;
1444 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
1445 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1446 psinfo->pr_nice = task_nice(p);
1447 psinfo->pr_flag = p->flags;
1448 SET_UID(psinfo->pr_uid, p->uid);
1449 SET_GID(psinfo->pr_gid, p->gid);
1450 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1451
1452 return 0;
1453 }
1454
1455 /* Here is the structure in which status of each thread is captured. */
1456 struct elf_thread_status
1457 {
1458 struct list_head list;
1459 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1460 elf_fpregset_t fpu; /* NT_PRFPREG */
1461 struct task_struct *thread;
1462 #ifdef ELF_CORE_COPY_XFPREGS
1463 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
1464 #endif
1465 struct memelfnote notes[3];
1466 int num_notes;
1467 };
1468
1469 /*
1470 * In order to add the specific thread information for the elf file format,
1471 * we need to keep a linked list of every thread's pr_status and then create
1472 * a single section for them in the final core file.
1473 */
1474 static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1475 {
1476 struct task_struct *p = t->thread;
1477 int sz = 0;
1478
1479 t->num_notes = 0;
1480
1481 fill_prstatus(&t->prstatus, p, signr);
1482 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1483
1484 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1485 &t->prstatus);
1486 t->num_notes++;
1487 sz += notesize(&t->notes[0]);
1488
1489 t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, &t->fpu);
1490 if (t->prstatus.pr_fpvalid) {
1491 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1492 &t->fpu);
1493 t->num_notes++;
1494 sz += notesize(&t->notes[1]);
1495 }
1496
1497 #ifdef ELF_CORE_COPY_XFPREGS
1498 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
1499 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1500 sizeof(t->xfpu), &t->xfpu);
1501 t->num_notes++;
1502 sz += notesize(&t->notes[2]);
1503 }
1504 #endif
1505 return sz;
1506 }
1507
1508 /*
1509 * dump the segments for an MMU process
1510 */
1511 #ifdef CONFIG_MMU
1512 static int elf_fdpic_dump_segments(struct file *file, size_t *size,
1513 unsigned long *limit, unsigned long mm_flags)
1514 {
1515 struct vm_area_struct *vma;
1516
1517 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
1518 unsigned long addr;
1519
1520 if (!maydump(vma, mm_flags))
1521 continue;
1522
1523 for (addr = vma->vm_start;
1524 addr < vma->vm_end;
1525 addr += PAGE_SIZE
1526 ) {
1527 struct vm_area_struct *vma;
1528 struct page *page;
1529
1530 if (get_user_pages(current, current->mm, addr, 1, 0, 1,
1531 &page, &vma) <= 0) {
1532 DUMP_SEEK(file->f_pos + PAGE_SIZE);
1533 }
1534 else if (page == ZERO_PAGE(0)) {
1535 page_cache_release(page);
1536 DUMP_SEEK(file->f_pos + PAGE_SIZE);
1537 }
1538 else {
1539 void *kaddr;
1540
1541 flush_cache_page(vma, addr, page_to_pfn(page));
1542 kaddr = kmap(page);
1543 if ((*size += PAGE_SIZE) > *limit ||
1544 !dump_write(file, kaddr, PAGE_SIZE)
1545 ) {
1546 kunmap(page);
1547 page_cache_release(page);
1548 return -EIO;
1549 }
1550 kunmap(page);
1551 page_cache_release(page);
1552 }
1553 }
1554 }
1555
1556 return 0;
1557
1558 end_coredump:
1559 return -EFBIG;
1560 }
1561 #endif
1562
1563 /*
1564 * dump the segments for a NOMMU process
1565 */
1566 #ifndef CONFIG_MMU
1567 static int elf_fdpic_dump_segments(struct file *file, size_t *size,
1568 unsigned long *limit, unsigned long mm_flags)
1569 {
1570 struct vm_list_struct *vml;
1571
1572 for (vml = current->mm->context.vmlist; vml; vml = vml->next) {
1573 struct vm_area_struct *vma = vml->vma;
1574
1575 if (!maydump(vma, mm_flags))
1576 continue;
1577
1578 if ((*size += PAGE_SIZE) > *limit)
1579 return -EFBIG;
1580
1581 if (!dump_write(file, (void *) vma->vm_start,
1582 vma->vm_end - vma->vm_start))
1583 return -EIO;
1584 }
1585
1586 return 0;
1587 }
1588 #endif
1589
1590 /*
1591 * Actual dumper
1592 *
1593 * This is a two-pass process; first we find the offsets of the bits,
1594 * and then they are actually written out. If we run out of core limit
1595 * we just truncate.
1596 */
1597 static int elf_fdpic_core_dump(long signr, struct pt_regs *regs,
1598 struct file *file, unsigned long limit)
1599 {
1600 #define NUM_NOTES 6
1601 int has_dumped = 0;
1602 mm_segment_t fs;
1603 int segs;
1604 size_t size = 0;
1605 int i;
1606 struct vm_area_struct *vma;
1607 struct elfhdr *elf = NULL;
1608 loff_t offset = 0, dataoff;
1609 int numnote;
1610 struct memelfnote *notes = NULL;
1611 struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
1612 struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */
1613 LIST_HEAD(thread_list);
1614 struct list_head *t;
1615 elf_fpregset_t *fpu = NULL;
1616 #ifdef ELF_CORE_COPY_XFPREGS
1617 elf_fpxregset_t *xfpu = NULL;
1618 #endif
1619 int thread_status_size = 0;
1620 #ifndef CONFIG_MMU
1621 struct vm_list_struct *vml;
1622 #endif
1623 elf_addr_t *auxv;
1624 unsigned long mm_flags;
1625
1626 /*
1627 * We no longer stop all VM operations.
1628 *
1629 * This is because those proceses that could possibly change map_count
1630 * or the mmap / vma pages are now blocked in do_exit on current
1631 * finishing this core dump.
1632 *
1633 * Only ptrace can touch these memory addresses, but it doesn't change
1634 * the map_count or the pages allocated. So no possibility of crashing
1635 * exists while dumping the mm->vm_next areas to the core file.
1636 */
1637
1638 /* alloc memory for large data structures: too large to be on stack */
1639 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1640 if (!elf)
1641 goto cleanup;
1642 prstatus = kzalloc(sizeof(*prstatus), GFP_KERNEL);
1643 if (!prstatus)
1644 goto cleanup;
1645 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1646 if (!psinfo)
1647 goto cleanup;
1648 notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL);
1649 if (!notes)
1650 goto cleanup;
1651 fpu = kmalloc(sizeof(*fpu), GFP_KERNEL);
1652 if (!fpu)
1653 goto cleanup;
1654 #ifdef ELF_CORE_COPY_XFPREGS
1655 xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL);
1656 if (!xfpu)
1657 goto cleanup;
1658 #endif
1659
1660 if (signr) {
1661 struct core_thread *ct;
1662 struct elf_thread_status *tmp;
1663
1664 for (ct = current->mm->core_state->dumper.next;
1665 ct; ct = ct->next) {
1666 tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
1667 if (!tmp)
1668 goto cleanup;
1669
1670 tmp->thread = ct->task;
1671 list_add(&tmp->list, &thread_list);
1672 }
1673
1674 list_for_each(t, &thread_list) {
1675 struct elf_thread_status *tmp;
1676 int sz;
1677
1678 tmp = list_entry(t, struct elf_thread_status, list);
1679 sz = elf_dump_thread_status(signr, tmp);
1680 thread_status_size += sz;
1681 }
1682 }
1683
1684 /* now collect the dump for the current */
1685 fill_prstatus(prstatus, current, signr);
1686 elf_core_copy_regs(&prstatus->pr_reg, regs);
1687
1688 #ifdef CONFIG_MMU
1689 segs = current->mm->map_count;
1690 #else
1691 segs = 0;
1692 for (vml = current->mm->context.vmlist; vml; vml = vml->next)
1693 segs++;
1694 #endif
1695 #ifdef ELF_CORE_EXTRA_PHDRS
1696 segs += ELF_CORE_EXTRA_PHDRS;
1697 #endif
1698
1699 /* Set up header */
1700 fill_elf_fdpic_header(elf, segs + 1); /* including notes section */
1701
1702 has_dumped = 1;
1703 current->flags |= PF_DUMPCORE;
1704
1705 /*
1706 * Set up the notes in similar form to SVR4 core dumps made
1707 * with info from their /proc.
1708 */
1709
1710 fill_note(notes + 0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus);
1711 fill_psinfo(psinfo, current->group_leader, current->mm);
1712 fill_note(notes + 1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1713
1714 numnote = 2;
1715
1716 auxv = (elf_addr_t *) current->mm->saved_auxv;
1717
1718 i = 0;
1719 do
1720 i += 2;
1721 while (auxv[i - 2] != AT_NULL);
1722 fill_note(&notes[numnote++], "CORE", NT_AUXV,
1723 i * sizeof(elf_addr_t), auxv);
1724
1725 /* Try to dump the FPU. */
1726 if ((prstatus->pr_fpvalid =
1727 elf_core_copy_task_fpregs(current, regs, fpu)))
1728 fill_note(notes + numnote++,
1729 "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
1730 #ifdef ELF_CORE_COPY_XFPREGS
1731 if (elf_core_copy_task_xfpregs(current, xfpu))
1732 fill_note(notes + numnote++,
1733 "LINUX", ELF_CORE_XFPREG_TYPE, sizeof(*xfpu), xfpu);
1734 #endif
1735
1736 fs = get_fs();
1737 set_fs(KERNEL_DS);
1738
1739 DUMP_WRITE(elf, sizeof(*elf));
1740 offset += sizeof(*elf); /* Elf header */
1741 offset += (segs+1) * sizeof(struct elf_phdr); /* Program headers */
1742
1743 /* Write notes phdr entry */
1744 {
1745 struct elf_phdr phdr;
1746 int sz = 0;
1747
1748 for (i = 0; i < numnote; i++)
1749 sz += notesize(notes + i);
1750
1751 sz += thread_status_size;
1752
1753 fill_elf_note_phdr(&phdr, sz, offset);
1754 offset += sz;
1755 DUMP_WRITE(&phdr, sizeof(phdr));
1756 }
1757
1758 /* Page-align dumped data */
1759 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1760
1761 /*
1762 * We must use the same mm->flags while dumping core to avoid
1763 * inconsistency between the program headers and bodies, otherwise an
1764 * unusable core file can be generated.
1765 */
1766 mm_flags = current->mm->flags;
1767
1768 /* write program headers for segments dump */
1769 for (
1770 #ifdef CONFIG_MMU
1771 vma = current->mm->mmap; vma; vma = vma->vm_next
1772 #else
1773 vml = current->mm->context.vmlist; vml; vml = vml->next
1774 #endif
1775 ) {
1776 struct elf_phdr phdr;
1777 size_t sz;
1778
1779 #ifndef CONFIG_MMU
1780 vma = vml->vma;
1781 #endif
1782
1783 sz = vma->vm_end - vma->vm_start;
1784
1785 phdr.p_type = PT_LOAD;
1786 phdr.p_offset = offset;
1787 phdr.p_vaddr = vma->vm_start;
1788 phdr.p_paddr = 0;
1789 phdr.p_filesz = maydump(vma, mm_flags) ? sz : 0;
1790 phdr.p_memsz = sz;
1791 offset += phdr.p_filesz;
1792 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
1793 if (vma->vm_flags & VM_WRITE)
1794 phdr.p_flags |= PF_W;
1795 if (vma->vm_flags & VM_EXEC)
1796 phdr.p_flags |= PF_X;
1797 phdr.p_align = ELF_EXEC_PAGESIZE;
1798
1799 DUMP_WRITE(&phdr, sizeof(phdr));
1800 }
1801
1802 #ifdef ELF_CORE_WRITE_EXTRA_PHDRS
1803 ELF_CORE_WRITE_EXTRA_PHDRS;
1804 #endif
1805
1806 /* write out the notes section */
1807 for (i = 0; i < numnote; i++)
1808 if (!writenote(notes + i, file))
1809 goto end_coredump;
1810
1811 /* write out the thread status notes section */
1812 list_for_each(t, &thread_list) {
1813 struct elf_thread_status *tmp =
1814 list_entry(t, struct elf_thread_status, list);
1815
1816 for (i = 0; i < tmp->num_notes; i++)
1817 if (!writenote(&tmp->notes[i], file))
1818 goto end_coredump;
1819 }
1820
1821 DUMP_SEEK(dataoff);
1822
1823 if (elf_fdpic_dump_segments(file, &size, &limit, mm_flags) < 0)
1824 goto end_coredump;
1825
1826 #ifdef ELF_CORE_WRITE_EXTRA_DATA
1827 ELF_CORE_WRITE_EXTRA_DATA;
1828 #endif
1829
1830 if (file->f_pos != offset) {
1831 /* Sanity check */
1832 printk(KERN_WARNING
1833 "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n",
1834 file->f_pos, offset);
1835 }
1836
1837 end_coredump:
1838 set_fs(fs);
1839
1840 cleanup:
1841 while (!list_empty(&thread_list)) {
1842 struct list_head *tmp = thread_list.next;
1843 list_del(tmp);
1844 kfree(list_entry(tmp, struct elf_thread_status, list));
1845 }
1846
1847 kfree(elf);
1848 kfree(prstatus);
1849 kfree(psinfo);
1850 kfree(notes);
1851 kfree(fpu);
1852 #ifdef ELF_CORE_COPY_XFPREGS
1853 kfree(xfpu);
1854 #endif
1855 return has_dumped;
1856 #undef NUM_NOTES
1857 }
1858
1859 #endif /* USE_ELF_CORE_DUMP */
linux 2.6 git repository for openrd