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PM: Add initcall_debug style timing for suspend/resume
[linux-2.6/x86.git] / fs / binfmt_elf_fdpic.c
blob79d2b1aa389f656f4952335955ab7bae89e41fa0
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 #ifdef ELF_FDPIC_PLAT_INIT
172 unsigned long dynaddr;
173 #endif
174 struct file *interpreter = NULL; /* to shut gcc up */
175 char *interpreter_name = NULL;
176 int executable_stack;
177 int retval, i;
178
179 kdebug("____ LOAD %d ____", current->pid);
180
181 memset(&exec_params, 0, sizeof(exec_params));
182 memset(&interp_params, 0, sizeof(interp_params));
183
184 exec_params.hdr = *(struct elfhdr *) bprm->buf;
185 exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE;
186
187 /* check that this is a binary we know how to deal with */
188 retval = -ENOEXEC;
189 if (!is_elf_fdpic(&exec_params.hdr, bprm->file))
190 goto error;
191
192 /* read the program header table */
193 retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);
194 if (retval < 0)
195 goto error;
196
197 /* scan for a program header that specifies an interpreter */
198 phdr = exec_params.phdrs;
199
200 for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) {
201 switch (phdr->p_type) {
202 case PT_INTERP:
203 retval = -ENOMEM;
204 if (phdr->p_filesz > PATH_MAX)
205 goto error;
206 retval = -ENOENT;
207 if (phdr->p_filesz < 2)
208 goto error;
209
210 /* read the name of the interpreter into memory */
211 interpreter_name = kmalloc(phdr->p_filesz, GFP_KERNEL);
212 if (!interpreter_name)
213 goto error;
214
215 retval = kernel_read(bprm->file,
216 phdr->p_offset,
217 interpreter_name,
218 phdr->p_filesz);
219 if (unlikely(retval != phdr->p_filesz)) {
220 if (retval >= 0)
221 retval = -ENOEXEC;
222 goto error;
223 }
224
225 retval = -ENOENT;
226 if (interpreter_name[phdr->p_filesz - 1] != '\0')
227 goto error;
228
229 kdebug("Using ELF interpreter %s", interpreter_name);
230
231 /* replace the program with the interpreter */
232 interpreter = open_exec(interpreter_name);
233 retval = PTR_ERR(interpreter);
234 if (IS_ERR(interpreter)) {
235 interpreter = NULL;
236 goto error;
237 }
238
239 /*
240 * If the binary is not readable then enforce
241 * mm->dumpable = 0 regardless of the interpreter's
242 * permissions.
243 */
244 if (file_permission(interpreter, MAY_READ) < 0)
245 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
246
247 retval = kernel_read(interpreter, 0, bprm->buf,
248 BINPRM_BUF_SIZE);
249 if (unlikely(retval != BINPRM_BUF_SIZE)) {
250 if (retval >= 0)
251 retval = -ENOEXEC;
252 goto error;
253 }
254
255 interp_params.hdr = *((struct elfhdr *) bprm->buf);
256 break;
257
258 case PT_LOAD:
259 #ifdef CONFIG_MMU
260 if (exec_params.load_addr == 0)
261 exec_params.load_addr = phdr->p_vaddr;
262 #endif
263 break;
264 }
265
266 }
267
268 if (elf_check_const_displacement(&exec_params.hdr))
269 exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
270
271 /* perform insanity checks on the interpreter */
272 if (interpreter_name) {
273 retval = -ELIBBAD;
274 if (!is_elf_fdpic(&interp_params.hdr, interpreter))
275 goto error;
276
277 interp_params.flags = ELF_FDPIC_FLAG_PRESENT;
278
279 /* read the interpreter's program header table */
280 retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter);
281 if (retval < 0)
282 goto error;
283 }
284
285 stack_size = exec_params.stack_size;
286 if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
287 executable_stack = EXSTACK_ENABLE_X;
288 else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
289 executable_stack = EXSTACK_DISABLE_X;
290 else
291 executable_stack = EXSTACK_DEFAULT;
292
293 if (stack_size == 0) {
294 stack_size = interp_params.stack_size;
295 if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
296 executable_stack = EXSTACK_ENABLE_X;
297 else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
298 executable_stack = EXSTACK_DISABLE_X;
299 else
300 executable_stack = EXSTACK_DEFAULT;
301 }
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 |
384 MAP_UNINITIALIZED | MAP_GROWSDOWN,
385 0);
386
387 if (IS_ERR_VALUE(current->mm->start_brk)) {
388 up_write(&current->mm->mmap_sem);
389 retval = current->mm->start_brk;
390 current->mm->start_brk = 0;
391 goto error_kill;
392 }
393
394 up_write(&current->mm->mmap_sem);
395
396 current->mm->brk = current->mm->start_brk;
397 current->mm->context.end_brk = current->mm->start_brk;
398 current->mm->context.end_brk +=
399 (stack_size > PAGE_SIZE) ? (stack_size - PAGE_SIZE) : 0;
400 current->mm->start_stack = current->mm->start_brk + stack_size;
401 #endif
402
403 install_exec_creds(bprm);
404 current->flags &= ~PF_FORKNOEXEC;
405 if (create_elf_fdpic_tables(bprm, current->mm,
406 &exec_params, &interp_params) < 0)
407 goto error_kill;
408
409 kdebug("- start_code %lx", current->mm->start_code);
410 kdebug("- end_code %lx", current->mm->end_code);
411 kdebug("- start_data %lx", current->mm->start_data);
412 kdebug("- end_data %lx", current->mm->end_data);
413 kdebug("- start_brk %lx", current->mm->start_brk);
414 kdebug("- brk %lx", current->mm->brk);
415 kdebug("- start_stack %lx", current->mm->start_stack);
416
417 #ifdef ELF_FDPIC_PLAT_INIT
418 /*
419 * The ABI may specify that certain registers be set up in special
420 * ways (on i386 %edx is the address of a DT_FINI function, for
421 * example. This macro performs whatever initialization to
422 * the regs structure is required.
423 */
424 dynaddr = interp_params.dynamic_addr ?: exec_params.dynamic_addr;
425 ELF_FDPIC_PLAT_INIT(regs, exec_params.map_addr, interp_params.map_addr,
426 dynaddr);
427 #endif
428
429 /* everything is now ready... get the userspace context ready to roll */
430 entryaddr = interp_params.entry_addr ?: exec_params.entry_addr;
431 start_thread(regs, entryaddr, current->mm->start_stack);
432
433 retval = 0;
434
435 error:
436 if (interpreter) {
437 allow_write_access(interpreter);
438 fput(interpreter);
439 }
440 kfree(interpreter_name);
441 kfree(exec_params.phdrs);
442 kfree(exec_params.loadmap);
443 kfree(interp_params.phdrs);
444 kfree(interp_params.loadmap);
445 return retval;
446
447 /* unrecoverable error - kill the process */
448 error_kill:
449 send_sig(SIGSEGV, current, 0);
450 goto error;
451
452 }
453
454 /*****************************************************************************/
455
456 #ifndef ELF_BASE_PLATFORM
457 /*
458 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
459 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
460 * will be copied to the user stack in the same manner as AT_PLATFORM.
461 */
462 #define ELF_BASE_PLATFORM NULL
463 #endif
464
465 /*
466 * present useful information to the program by shovelling it onto the new
467 * process's stack
468 */
469 static int create_elf_fdpic_tables(struct linux_binprm *bprm,
470 struct mm_struct *mm,
471 struct elf_fdpic_params *exec_params,
472 struct elf_fdpic_params *interp_params)
473 {
474 const struct cred *cred = current_cred();
475 unsigned long sp, csp, nitems;
476 elf_caddr_t __user *argv, *envp;
477 size_t platform_len = 0, len;
478 char *k_platform, *k_base_platform;
479 char __user *u_platform, *u_base_platform, *p;
480 long hwcap;
481 int loop;
482 int nr; /* reset for each csp adjustment */
483
484 #ifdef CONFIG_MMU
485 /* In some cases (e.g. Hyper-Threading), we want to avoid L1 evictions
486 * by the processes running on the same package. One thing we can do is
487 * to shuffle the initial stack for them, so we give the architecture
488 * an opportunity to do so here.
489 */
490 sp = arch_align_stack(bprm->p);
491 #else
492 sp = mm->start_stack;
493
494 /* stack the program arguments and environment */
495 if (elf_fdpic_transfer_args_to_stack(bprm, &sp) < 0)
496 return -EFAULT;
497 #endif
498
499 hwcap = ELF_HWCAP;
500
501 /*
502 * If this architecture has a platform capability string, copy it
503 * to userspace. In some cases (Sparc), this info is impossible
504 * for userspace to get any other way, in others (i386) it is
505 * merely difficult.
506 */
507 k_platform = ELF_PLATFORM;
508 u_platform = NULL;
509
510 if (k_platform) {
511 platform_len = strlen(k_platform) + 1;
512 sp -= platform_len;
513 u_platform = (char __user *) sp;
514 if (__copy_to_user(u_platform, k_platform, platform_len) != 0)
515 return -EFAULT;
516 }
517
518 /*
519 * If this architecture has a "base" platform capability
520 * string, copy it to userspace.
521 */
522 k_base_platform = ELF_BASE_PLATFORM;
523 u_base_platform = NULL;
524
525 if (k_base_platform) {
526 platform_len = strlen(k_base_platform) + 1;
527 sp -= platform_len;
528 u_base_platform = (char __user *) sp;
529 if (__copy_to_user(u_base_platform, k_base_platform, platform_len) != 0)
530 return -EFAULT;
531 }
532
533 sp &= ~7UL;
534
535 /* stack the load map(s) */
536 len = sizeof(struct elf32_fdpic_loadmap);
537 len += sizeof(struct elf32_fdpic_loadseg) * exec_params->loadmap->nsegs;
538 sp = (sp - len) & ~7UL;
539 exec_params->map_addr = sp;
540
541 if (copy_to_user((void __user *) sp, exec_params->loadmap, len) != 0)
542 return -EFAULT;
543
544 current->mm->context.exec_fdpic_loadmap = (unsigned long) sp;
545
546 if (interp_params->loadmap) {
547 len = sizeof(struct elf32_fdpic_loadmap);
548 len += sizeof(struct elf32_fdpic_loadseg) *
549 interp_params->loadmap->nsegs;
550 sp = (sp - len) & ~7UL;
551 interp_params->map_addr = sp;
552
553 if (copy_to_user((void __user *) sp, interp_params->loadmap,
554 len) != 0)
555 return -EFAULT;
556
557 current->mm->context.interp_fdpic_loadmap = (unsigned long) sp;
558 }
559
560 /* force 16 byte _final_ alignment here for generality */
561 #define DLINFO_ITEMS 15
562
563 nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) +
564 (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH;
565
566 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD)
567 nitems++;
568
569 csp = sp;
570 sp -= nitems * 2 * sizeof(unsigned long);
571 sp -= (bprm->envc + 1) * sizeof(char *); /* envv[] */
572 sp -= (bprm->argc + 1) * sizeof(char *); /* argv[] */
573 sp -= 1 * sizeof(unsigned long); /* argc */
574
575 csp -= sp & 15UL;
576 sp -= sp & 15UL;
577
578 /* put the ELF interpreter info on the stack */
579 #define NEW_AUX_ENT(id, val) \
580 do { \
581 struct { unsigned long _id, _val; } __user *ent; \
582 \
583 ent = (void __user *) csp; \
584 __put_user((id), &ent[nr]._id); \
585 __put_user((val), &ent[nr]._val); \
586 nr++; \
587 } while (0)
588
589 nr = 0;
590 csp -= 2 * sizeof(unsigned long);
591 NEW_AUX_ENT(AT_NULL, 0);
592 if (k_platform) {
593 nr = 0;
594 csp -= 2 * sizeof(unsigned long);
595 NEW_AUX_ENT(AT_PLATFORM,
596 (elf_addr_t) (unsigned long) u_platform);
597 }
598
599 if (k_base_platform) {
600 nr = 0;
601 csp -= 2 * sizeof(unsigned long);
602 NEW_AUX_ENT(AT_BASE_PLATFORM,
603 (elf_addr_t) (unsigned long) u_base_platform);
604 }
605
606 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
607 nr = 0;
608 csp -= 2 * sizeof(unsigned long);
609 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
610 }
611
612 nr = 0;
613 csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long);
614 NEW_AUX_ENT(AT_HWCAP, hwcap);
615 NEW_AUX_ENT(AT_PAGESZ, PAGE_SIZE);
616 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
617 NEW_AUX_ENT(AT_PHDR, exec_params->ph_addr);
618 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
619 NEW_AUX_ENT(AT_PHNUM, exec_params->hdr.e_phnum);
620 NEW_AUX_ENT(AT_BASE, interp_params->elfhdr_addr);
621 NEW_AUX_ENT(AT_FLAGS, 0);
622 NEW_AUX_ENT(AT_ENTRY, exec_params->entry_addr);
623 NEW_AUX_ENT(AT_UID, (elf_addr_t) cred->uid);
624 NEW_AUX_ENT(AT_EUID, (elf_addr_t) cred->euid);
625 NEW_AUX_ENT(AT_GID, (elf_addr_t) cred->gid);
626 NEW_AUX_ENT(AT_EGID, (elf_addr_t) cred->egid);
627 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
628 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
629
630 #ifdef ARCH_DLINFO
631 nr = 0;
632 csp -= AT_VECTOR_SIZE_ARCH * 2 * sizeof(unsigned long);
633
634 /* ARCH_DLINFO must come last so platform specific code can enforce
635 * special alignment requirements on the AUXV if necessary (eg. PPC).
636 */
637 ARCH_DLINFO;
638 #endif
639 #undef NEW_AUX_ENT
640
641 /* allocate room for argv[] and envv[] */
642 csp -= (bprm->envc + 1) * sizeof(elf_caddr_t);
643 envp = (elf_caddr_t __user *) csp;
644 csp -= (bprm->argc + 1) * sizeof(elf_caddr_t);
645 argv = (elf_caddr_t __user *) csp;
646
647 /* stack argc */
648 csp -= sizeof(unsigned long);
649 __put_user(bprm->argc, (unsigned long __user *) csp);
650
651 BUG_ON(csp != sp);
652
653 /* fill in the argv[] array */
654 #ifdef CONFIG_MMU
655 current->mm->arg_start = bprm->p;
656 #else
657 current->mm->arg_start = current->mm->start_stack -
658 (MAX_ARG_PAGES * PAGE_SIZE - bprm->p);
659 #endif
660
661 p = (char __user *) current->mm->arg_start;
662 for (loop = bprm->argc; loop > 0; loop--) {
663 __put_user((elf_caddr_t) p, argv++);
664 len = strnlen_user(p, MAX_ARG_STRLEN);
665 if (!len || len > MAX_ARG_STRLEN)
666 return -EINVAL;
667 p += len;
668 }
669 __put_user(NULL, argv);
670 current->mm->arg_end = (unsigned long) p;
671
672 /* fill in the envv[] array */
673 current->mm->env_start = (unsigned long) p;
674 for (loop = bprm->envc; loop > 0; loop--) {
675 __put_user((elf_caddr_t)(unsigned long) p, envp++);
676 len = strnlen_user(p, MAX_ARG_STRLEN);
677 if (!len || len > MAX_ARG_STRLEN)
678 return -EINVAL;
679 p += len;
680 }
681 __put_user(NULL, envp);
682 current->mm->env_end = (unsigned long) p;
683
684 mm->start_stack = (unsigned long) sp;
685 return 0;
686 }
687
688 /*****************************************************************************/
689 /*
690 * transfer the program arguments and environment from the holding pages onto
691 * the stack
692 */
693 #ifndef CONFIG_MMU
694 static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *bprm,
695 unsigned long *_sp)
696 {
697 unsigned long index, stop, sp;
698 char *src;
699 int ret = 0;
700
701 stop = bprm->p >> PAGE_SHIFT;
702 sp = *_sp;
703
704 for (index = MAX_ARG_PAGES - 1; index >= stop; index--) {
705 src = kmap(bprm->page[index]);
706 sp -= PAGE_SIZE;
707 if (copy_to_user((void *) sp, src, PAGE_SIZE) != 0)
708 ret = -EFAULT;
709 kunmap(bprm->page[index]);
710 if (ret < 0)
711 goto out;
712 }
713
714 *_sp = (*_sp - (MAX_ARG_PAGES * PAGE_SIZE - bprm->p)) & ~15;
715
716 out:
717 return ret;
718 }
719 #endif
720
721 /*****************************************************************************/
722 /*
723 * load the appropriate binary image (executable or interpreter) into memory
724 * - we assume no MMU is available
725 * - if no other PIC bits are set in params->hdr->e_flags
726 * - we assume that the LOADable segments in the binary are independently relocatable
727 * - we assume R/O executable segments are shareable
728 * - else
729 * - we assume the loadable parts of the image to require fixed displacement
730 * - the image is not shareable
731 */
732 static int elf_fdpic_map_file(struct elf_fdpic_params *params,
733 struct file *file,
734 struct mm_struct *mm,
735 const char *what)
736 {
737 struct elf32_fdpic_loadmap *loadmap;
738 #ifdef CONFIG_MMU
739 struct elf32_fdpic_loadseg *mseg;
740 #endif
741 struct elf32_fdpic_loadseg *seg;
742 struct elf32_phdr *phdr;
743 unsigned long load_addr, stop;
744 unsigned nloads, tmp;
745 size_t size;
746 int loop, ret;
747
748 /* allocate a load map table */
749 nloads = 0;
750 for (loop = 0; loop < params->hdr.e_phnum; loop++)
751 if (params->phdrs[loop].p_type == PT_LOAD)
752 nloads++;
753
754 if (nloads == 0)
755 return -ELIBBAD;
756
757 size = sizeof(*loadmap) + nloads * sizeof(*seg);
758 loadmap = kzalloc(size, GFP_KERNEL);
759 if (!loadmap)
760 return -ENOMEM;
761
762 params->loadmap = loadmap;
763
764 loadmap->version = ELF32_FDPIC_LOADMAP_VERSION;
765 loadmap->nsegs = nloads;
766
767 load_addr = params->load_addr;
768 seg = loadmap->segs;
769
770 /* map the requested LOADs into the memory space */
771 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
772 case ELF_FDPIC_FLAG_CONSTDISP:
773 case ELF_FDPIC_FLAG_CONTIGUOUS:
774 #ifndef CONFIG_MMU
775 ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm);
776 if (ret < 0)
777 return ret;
778 break;
779 #endif
780 default:
781 ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm);
782 if (ret < 0)
783 return ret;
784 break;
785 }
786
787 /* map the entry point */
788 if (params->hdr.e_entry) {
789 seg = loadmap->segs;
790 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
791 if (params->hdr.e_entry >= seg->p_vaddr &&
792 params->hdr.e_entry < seg->p_vaddr + seg->p_memsz) {
793 params->entry_addr =
794 (params->hdr.e_entry - seg->p_vaddr) +
795 seg->addr;
796 break;
797 }
798 }
799 }
800
801 /* determine where the program header table has wound up if mapped */
802 stop = params->hdr.e_phoff;
803 stop += params->hdr.e_phnum * sizeof (struct elf_phdr);
804 phdr = params->phdrs;
805
806 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
807 if (phdr->p_type != PT_LOAD)
808 continue;
809
810 if (phdr->p_offset > params->hdr.e_phoff ||
811 phdr->p_offset + phdr->p_filesz < stop)
812 continue;
813
814 seg = loadmap->segs;
815 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
816 if (phdr->p_vaddr >= seg->p_vaddr &&
817 phdr->p_vaddr + phdr->p_filesz <=
818 seg->p_vaddr + seg->p_memsz) {
819 params->ph_addr =
820 (phdr->p_vaddr - seg->p_vaddr) +
821 seg->addr +
822 params->hdr.e_phoff - phdr->p_offset;
823 break;
824 }
825 }
826 break;
827 }
828
829 /* determine where the dynamic section has wound up if there is one */
830 phdr = params->phdrs;
831 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
832 if (phdr->p_type != PT_DYNAMIC)
833 continue;
834
835 seg = loadmap->segs;
836 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
837 if (phdr->p_vaddr >= seg->p_vaddr &&
838 phdr->p_vaddr + phdr->p_memsz <=
839 seg->p_vaddr + seg->p_memsz) {
840 params->dynamic_addr =
841 (phdr->p_vaddr - seg->p_vaddr) +
842 seg->addr;
843
844 /* check the dynamic section contains at least
845 * one item, and that the last item is a NULL
846 * entry */
847 if (phdr->p_memsz == 0 ||
848 phdr->p_memsz % sizeof(Elf32_Dyn) != 0)
849 goto dynamic_error;
850
851 tmp = phdr->p_memsz / sizeof(Elf32_Dyn);
852 if (((Elf32_Dyn *)
853 params->dynamic_addr)[tmp - 1].d_tag != 0)
854 goto dynamic_error;
855 break;
856 }
857 }
858 break;
859 }
860
861 /* now elide adjacent segments in the load map on MMU linux
862 * - on uClinux the holes between may actually be filled with system
863 * stuff or stuff from other processes
864 */
865 #ifdef CONFIG_MMU
866 nloads = loadmap->nsegs;
867 mseg = loadmap->segs;
868 seg = mseg + 1;
869 for (loop = 1; loop < nloads; loop++) {
870 /* see if we have a candidate for merging */
871 if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) {
872 load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz);
873 if (load_addr == (seg->addr & PAGE_MASK)) {
874 mseg->p_memsz +=
875 load_addr -
876 (mseg->addr + mseg->p_memsz);
877 mseg->p_memsz += seg->addr & ~PAGE_MASK;
878 mseg->p_memsz += seg->p_memsz;
879 loadmap->nsegs--;
880 continue;
881 }
882 }
883
884 mseg++;
885 if (mseg != seg)
886 *mseg = *seg;
887 }
888 #endif
889
890 kdebug("Mapped Object [%s]:", what);
891 kdebug("- elfhdr : %lx", params->elfhdr_addr);
892 kdebug("- entry : %lx", params->entry_addr);
893 kdebug("- PHDR[] : %lx", params->ph_addr);
894 kdebug("- DYNAMIC[]: %lx", params->dynamic_addr);
895 seg = loadmap->segs;
896 for (loop = 0; loop < loadmap->nsegs; loop++, seg++)
897 kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]",
898 loop,
899 seg->addr, seg->addr + seg->p_memsz - 1,
900 seg->p_vaddr, seg->p_memsz);
901
902 return 0;
903
904 dynamic_error:
905 printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n",
906 what, file->f_path.dentry->d_inode->i_ino);
907 return -ELIBBAD;
908 }
909
910 /*****************************************************************************/
911 /*
912 * map a file with constant displacement under uClinux
913 */
914 #ifndef CONFIG_MMU
915 static int elf_fdpic_map_file_constdisp_on_uclinux(
916 struct elf_fdpic_params *params,
917 struct file *file,
918 struct mm_struct *mm)
919 {
920 struct elf32_fdpic_loadseg *seg;
921 struct elf32_phdr *phdr;
922 unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags;
923 loff_t fpos;
924 int loop, ret;
925
926 load_addr = params->load_addr;
927 seg = params->loadmap->segs;
928
929 /* determine the bounds of the contiguous overall allocation we must
930 * make */
931 phdr = params->phdrs;
932 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
933 if (params->phdrs[loop].p_type != PT_LOAD)
934 continue;
935
936 if (base > phdr->p_vaddr)
937 base = phdr->p_vaddr;
938 if (top < phdr->p_vaddr + phdr->p_memsz)
939 top = phdr->p_vaddr + phdr->p_memsz;
940 }
941
942 /* allocate one big anon block for everything */
943 mflags = MAP_PRIVATE;
944 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
945 mflags |= MAP_EXECUTABLE;
946
947 down_write(&mm->mmap_sem);
948 maddr = do_mmap(NULL, load_addr, top - base,
949 PROT_READ | PROT_WRITE | PROT_EXEC, mflags, 0);
950 up_write(&mm->mmap_sem);
951 if (IS_ERR_VALUE(maddr))
952 return (int) maddr;
953
954 if (load_addr != 0)
955 load_addr += PAGE_ALIGN(top - base);
956
957 /* and then load the file segments into it */
958 phdr = params->phdrs;
959 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
960 if (params->phdrs[loop].p_type != PT_LOAD)
961 continue;
962
963 fpos = phdr->p_offset;
964
965 seg->addr = maddr + (phdr->p_vaddr - base);
966 seg->p_vaddr = phdr->p_vaddr;
967 seg->p_memsz = phdr->p_memsz;
968
969 ret = file->f_op->read(file, (void *) seg->addr,
970 phdr->p_filesz, &fpos);
971 if (ret < 0)
972 return ret;
973
974 /* map the ELF header address if in this segment */
975 if (phdr->p_offset == 0)
976 params->elfhdr_addr = seg->addr;
977
978 /* clear any space allocated but not loaded */
979 if (phdr->p_filesz < phdr->p_memsz) {
980 ret = clear_user((void *) (seg->addr + phdr->p_filesz),
981 phdr->p_memsz - phdr->p_filesz);
982 if (ret)
983 return ret;
984 }
985
986 if (mm) {
987 if (phdr->p_flags & PF_X) {
988 if (!mm->start_code) {
989 mm->start_code = seg->addr;
990 mm->end_code = seg->addr +
991 phdr->p_memsz;
992 }
993 } else if (!mm->start_data) {
994 mm->start_data = seg->addr;
995 #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, ret;
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 ret = clear_user((void __user *) maddr, disp);
1125 if (ret)
1126 return ret;
1127 maddr += disp;
1128 }
1129
1130 /* clear any space allocated but not loaded
1131 * - on uClinux we can just clear the lot
1132 * - on MMU linux we'll get a SIGBUS beyond the last page
1133 * extant in the file
1134 */
1135 excess = phdr->p_memsz - phdr->p_filesz;
1136 excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
1137
1138 #ifdef CONFIG_MMU
1139 if (excess > excess1) {
1140 unsigned long xaddr = maddr + phdr->p_filesz + excess1;
1141 unsigned long xmaddr;
1142
1143 flags |= MAP_FIXED | MAP_ANONYMOUS;
1144 down_write(&mm->mmap_sem);
1145 xmaddr = do_mmap(NULL, xaddr, excess - excess1,
1146 prot, flags, 0);
1147 up_write(&mm->mmap_sem);
1148
1149 kdebug("mmap[%d] <anon>"
1150 " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",
1151 loop, xaddr, excess - excess1, prot, flags,
1152 xmaddr);
1153
1154 if (xmaddr != xaddr)
1155 return -ENOMEM;
1156 }
1157
1158 if (prot & PROT_WRITE && excess1 > 0) {
1159 kdebug("clear[%d] ad=%lx sz=%lx",
1160 loop, maddr + phdr->p_filesz, excess1);
1161 ret = clear_user((void __user *) maddr + phdr->p_filesz,
1162 excess1);
1163 if (ret)
1164 return ret;
1165 }
1166
1167 #else
1168 if (excess > 0) {
1169 kdebug("clear[%d] ad=%lx sz=%lx",
1170 loop, maddr + phdr->p_filesz, excess);
1171 ret = clear_user((void *) maddr + phdr->p_filesz, excess);
1172 if (ret)
1173 return ret;
1174 }
1175 #endif
1176
1177 if (mm) {
1178 if (phdr->p_flags & PF_X) {
1179 if (!mm->start_code) {
1180 mm->start_code = maddr;
1181 mm->end_code = maddr + phdr->p_memsz;
1182 }
1183 } else if (!mm->start_data) {
1184 mm->start_data = maddr;
1185 mm->end_data = maddr + phdr->p_memsz;
1186 }
1187 }
1188
1189 seg++;
1190 }
1191
1192 return 0;
1193 }
1194
1195 /*****************************************************************************/
1196 /*
1197 * ELF-FDPIC core dumper
1198 *
1199 * Modelled on fs/exec.c:aout_core_dump()
1200 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1201 *
1202 * Modelled on fs/binfmt_elf.c core dumper
1203 */
1204 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
1205
1206 /*
1207 * These are the only things you should do on a core-file: use only these
1208 * functions to write out all the necessary info.
1209 */
1210 static int dump_write(struct file *file, const void *addr, int nr)
1211 {
1212 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
1213 }
1214
1215 static int dump_seek(struct file *file, loff_t off)
1216 {
1217 if (file->f_op->llseek) {
1218 if (file->f_op->llseek(file, off, SEEK_SET) != off)
1219 return 0;
1220 } else {
1221 file->f_pos = off;
1222 }
1223 return 1;
1224 }
1225
1226 /*
1227 * Decide whether a segment is worth dumping; default is yes to be
1228 * sure (missing info is worse than too much; etc).
1229 * Personally I'd include everything, and use the coredump limit...
1230 *
1231 * I think we should skip something. But I am not sure how. H.J.
1232 */
1233 static int maydump(struct vm_area_struct *vma, unsigned long mm_flags)
1234 {
1235 int dump_ok;
1236
1237 /* Do not dump I/O mapped devices or special mappings */
1238 if (vma->vm_flags & (VM_IO | VM_RESERVED)) {
1239 kdcore("%08lx: %08lx: no (IO)", vma->vm_start, vma->vm_flags);
1240 return 0;
1241 }
1242
1243 /* If we may not read the contents, don't allow us to dump
1244 * them either. "dump_write()" can't handle it anyway.
1245 */
1246 if (!(vma->vm_flags & VM_READ)) {
1247 kdcore("%08lx: %08lx: no (!read)", vma->vm_start, vma->vm_flags);
1248 return 0;
1249 }
1250
1251 /* By default, dump shared memory if mapped from an anonymous file. */
1252 if (vma->vm_flags & VM_SHARED) {
1253 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0) {
1254 dump_ok = test_bit(MMF_DUMP_ANON_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 dump_ok = test_bit(MMF_DUMP_MAPPED_SHARED, &mm_flags);
1261 kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
1262 vma->vm_flags, dump_ok ? "yes" : "no");
1263 return dump_ok;
1264 }
1265
1266 #ifdef CONFIG_MMU
1267 /* By default, if it hasn't been written to, don't write it out */
1268 if (!vma->anon_vma) {
1269 dump_ok = test_bit(MMF_DUMP_MAPPED_PRIVATE, &mm_flags);
1270 kdcore("%08lx: %08lx: %s (!anon)", vma->vm_start,
1271 vma->vm_flags, dump_ok ? "yes" : "no");
1272 return dump_ok;
1273 }
1274 #endif
1275
1276 dump_ok = test_bit(MMF_DUMP_ANON_PRIVATE, &mm_flags);
1277 kdcore("%08lx: %08lx: %s", vma->vm_start, vma->vm_flags,
1278 dump_ok ? "yes" : "no");
1279 return dump_ok;
1280 }
1281
1282 /* An ELF note in memory */
1283 struct memelfnote
1284 {
1285 const char *name;
1286 int type;
1287 unsigned int datasz;
1288 void *data;
1289 };
1290
1291 static int notesize(struct memelfnote *en)
1292 {
1293 int sz;
1294
1295 sz = sizeof(struct elf_note);
1296 sz += roundup(strlen(en->name) + 1, 4);
1297 sz += roundup(en->datasz, 4);
1298
1299 return sz;
1300 }
1301
1302 /* #define DEBUG */
1303
1304 #define DUMP_WRITE(addr, nr) \
1305 do { if (!dump_write(file, (addr), (nr))) return 0; } while(0)
1306 #define DUMP_SEEK(off) \
1307 do { if (!dump_seek(file, (off))) return 0; } while(0)
1308
1309 static int writenote(struct memelfnote *men, struct file *file)
1310 {
1311 struct elf_note en;
1312
1313 en.n_namesz = strlen(men->name) + 1;
1314 en.n_descsz = men->datasz;
1315 en.n_type = men->type;
1316
1317 DUMP_WRITE(&en, sizeof(en));
1318 DUMP_WRITE(men->name, en.n_namesz);
1319 /* XXX - cast from long long to long to avoid need for libgcc.a */
1320 DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
1321 DUMP_WRITE(men->data, men->datasz);
1322 DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
1323
1324 return 1;
1325 }
1326 #undef DUMP_WRITE
1327 #undef DUMP_SEEK
1328
1329 #define DUMP_WRITE(addr, nr) \
1330 if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
1331 goto end_coredump;
1332
1333 static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)
1334 {
1335 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1336 elf->e_ident[EI_CLASS] = ELF_CLASS;
1337 elf->e_ident[EI_DATA] = ELF_DATA;
1338 elf->e_ident[EI_VERSION] = EV_CURRENT;
1339 elf->e_ident[EI_OSABI] = ELF_OSABI;
1340 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
1341
1342 elf->e_type = ET_CORE;
1343 elf->e_machine = ELF_ARCH;
1344 elf->e_version = EV_CURRENT;
1345 elf->e_entry = 0;
1346 elf->e_phoff = sizeof(struct elfhdr);
1347 elf->e_shoff = 0;
1348 elf->e_flags = ELF_FDPIC_CORE_EFLAGS;
1349 elf->e_ehsize = sizeof(struct elfhdr);
1350 elf->e_phentsize = sizeof(struct elf_phdr);
1351 elf->e_phnum = segs;
1352 elf->e_shentsize = 0;
1353 elf->e_shnum = 0;
1354 elf->e_shstrndx = 0;
1355 return;
1356 }
1357
1358 static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
1359 {
1360 phdr->p_type = PT_NOTE;
1361 phdr->p_offset = offset;
1362 phdr->p_vaddr = 0;
1363 phdr->p_paddr = 0;
1364 phdr->p_filesz = sz;
1365 phdr->p_memsz = 0;
1366 phdr->p_flags = 0;
1367 phdr->p_align = 0;
1368 return;
1369 }
1370
1371 static inline void fill_note(struct memelfnote *note, const char *name, int type,
1372 unsigned int sz, void *data)
1373 {
1374 note->name = name;
1375 note->type = type;
1376 note->datasz = sz;
1377 note->data = data;
1378 return;
1379 }
1380
1381 /*
1382 * fill up all the fields in prstatus from the given task struct, except
1383 * registers which need to be filled up seperately.
1384 */
1385 static void fill_prstatus(struct elf_prstatus *prstatus,
1386 struct task_struct *p, long signr)
1387 {
1388 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1389 prstatus->pr_sigpend = p->pending.signal.sig[0];
1390 prstatus->pr_sighold = p->blocked.sig[0];
1391 rcu_read_lock();
1392 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1393 rcu_read_unlock();
1394 prstatus->pr_pid = task_pid_vnr(p);
1395 prstatus->pr_pgrp = task_pgrp_vnr(p);
1396 prstatus->pr_sid = task_session_vnr(p);
1397 if (thread_group_leader(p)) {
1398 struct task_cputime cputime;
1399
1400 /*
1401 * This is the record for the group leader. It shows the
1402 * group-wide total, not its individual thread total.
1403 */
1404 thread_group_cputime(p, &cputime);
1405 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1406 cputime_to_timeval(cputime.stime, &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 const struct cred *cred;
1422 unsigned int i, len;
1423
1424 /* first copy the parameters from user space */
1425 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1426
1427 len = mm->arg_end - mm->arg_start;
1428 if (len >= ELF_PRARGSZ)
1429 len = ELF_PRARGSZ - 1;
1430 if (copy_from_user(&psinfo->pr_psargs,
1431 (const char __user *) mm->arg_start, len))
1432 return -EFAULT;
1433 for (i = 0; i < len; i++)
1434 if (psinfo->pr_psargs[i] == 0)
1435 psinfo->pr_psargs[i] = ' ';
1436 psinfo->pr_psargs[len] = 0;
1437
1438 rcu_read_lock();
1439 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1440 rcu_read_unlock();
1441 psinfo->pr_pid = task_pid_vnr(p);
1442 psinfo->pr_pgrp = task_pgrp_vnr(p);
1443 psinfo->pr_sid = task_session_vnr(p);
1444
1445 i = p->state ? ffz(~p->state) + 1 : 0;
1446 psinfo->pr_state = i;
1447 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
1448 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1449 psinfo->pr_nice = task_nice(p);
1450 psinfo->pr_flag = p->flags;
1451 rcu_read_lock();
1452 cred = __task_cred(p);
1453 SET_UID(psinfo->pr_uid, cred->uid);
1454 SET_GID(psinfo->pr_gid, cred->gid);
1455 rcu_read_unlock();
1456 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1457
1458 return 0;
1459 }
1460
1461 /* Here is the structure in which status of each thread is captured. */
1462 struct elf_thread_status
1463 {
1464 struct list_head list;
1465 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1466 elf_fpregset_t fpu; /* NT_PRFPREG */
1467 struct task_struct *thread;
1468 #ifdef ELF_CORE_COPY_XFPREGS
1469 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
1470 #endif
1471 struct memelfnote notes[3];
1472 int num_notes;
1473 };
1474
1475 /*
1476 * In order to add the specific thread information for the elf file format,
1477 * we need to keep a linked list of every thread's pr_status and then create
1478 * a single section for them in the final core file.
1479 */
1480 static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1481 {
1482 struct task_struct *p = t->thread;
1483 int sz = 0;
1484
1485 t->num_notes = 0;
1486
1487 fill_prstatus(&t->prstatus, p, signr);
1488 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1489
1490 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1491 &t->prstatus);
1492 t->num_notes++;
1493 sz += notesize(&t->notes[0]);
1494
1495 t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, &t->fpu);
1496 if (t->prstatus.pr_fpvalid) {
1497 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1498 &t->fpu);
1499 t->num_notes++;
1500 sz += notesize(&t->notes[1]);
1501 }
1502
1503 #ifdef ELF_CORE_COPY_XFPREGS
1504 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
1505 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1506 sizeof(t->xfpu), &t->xfpu);
1507 t->num_notes++;
1508 sz += notesize(&t->notes[2]);
1509 }
1510 #endif
1511 return sz;
1512 }
1513
1514 /*
1515 * dump the segments for an MMU process
1516 */
1517 #ifdef CONFIG_MMU
1518 static int elf_fdpic_dump_segments(struct file *file, size_t *size,
1519 unsigned long *limit, unsigned long mm_flags)
1520 {
1521 struct vm_area_struct *vma;
1522 int err = 0;
1523
1524 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
1525 unsigned long addr;
1526
1527 if (!maydump(vma, mm_flags))
1528 continue;
1529
1530 for (addr = vma->vm_start; addr < vma->vm_end;
1531 addr += PAGE_SIZE) {
1532 struct page *page = get_dump_page(addr);
1533 if (page) {
1534 void *kaddr = kmap(page);
1535 *size += PAGE_SIZE;
1536 if (*size > *limit)
1537 err = -EFBIG;
1538 else if (!dump_write(file, kaddr, PAGE_SIZE))
1539 err = -EIO;
1540 kunmap(page);
1541 page_cache_release(page);
1542 } else if (!dump_seek(file, file->f_pos + PAGE_SIZE))
1543 err = -EFBIG;
1544 if (err)
1545 goto out;
1546 }
1547 }
1548 out:
1549 return err;
1550 }
1551 #endif
1552
1553 /*
1554 * dump the segments for a NOMMU process
1555 */
1556 #ifndef CONFIG_MMU
1557 static int elf_fdpic_dump_segments(struct file *file, size_t *size,
1558 unsigned long *limit, unsigned long mm_flags)
1559 {
1560 struct vm_area_struct *vma;
1561
1562 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
1563 if (!maydump(vma, mm_flags))
1564 continue;
1565
1566 if ((*size += PAGE_SIZE) > *limit)
1567 return -EFBIG;
1568
1569 if (!dump_write(file, (void *) vma->vm_start,
1570 vma->vm_end - vma->vm_start))
1571 return -EIO;
1572 }
1573
1574 return 0;
1575 }
1576 #endif
1577
1578 /*
1579 * Actual dumper
1580 *
1581 * This is a two-pass process; first we find the offsets of the bits,
1582 * and then they are actually written out. If we run out of core limit
1583 * we just truncate.
1584 */
1585 static int elf_fdpic_core_dump(long signr, struct pt_regs *regs,
1586 struct file *file, unsigned long limit)
1587 {
1588 #define NUM_NOTES 6
1589 int has_dumped = 0;
1590 mm_segment_t fs;
1591 int segs;
1592 size_t size = 0;
1593 int i;
1594 struct vm_area_struct *vma;
1595 struct elfhdr *elf = NULL;
1596 loff_t offset = 0, dataoff;
1597 int numnote;
1598 struct memelfnote *notes = NULL;
1599 struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
1600 struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */
1601 LIST_HEAD(thread_list);
1602 struct list_head *t;
1603 elf_fpregset_t *fpu = NULL;
1604 #ifdef ELF_CORE_COPY_XFPREGS
1605 elf_fpxregset_t *xfpu = NULL;
1606 #endif
1607 int thread_status_size = 0;
1608 elf_addr_t *auxv;
1609 unsigned long mm_flags;
1610
1611 /*
1612 * We no longer stop all VM operations.
1613 *
1614 * This is because those proceses that could possibly change map_count
1615 * or the mmap / vma pages are now blocked in do_exit on current
1616 * finishing this core dump.
1617 *
1618 * Only ptrace can touch these memory addresses, but it doesn't change
1619 * the map_count or the pages allocated. So no possibility of crashing
1620 * exists while dumping the mm->vm_next areas to the core file.
1621 */
1622
1623 /* alloc memory for large data structures: too large to be on stack */
1624 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1625 if (!elf)
1626 goto cleanup;
1627 prstatus = kzalloc(sizeof(*prstatus), GFP_KERNEL);
1628 if (!prstatus)
1629 goto cleanup;
1630 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1631 if (!psinfo)
1632 goto cleanup;
1633 notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL);
1634 if (!notes)
1635 goto cleanup;
1636 fpu = kmalloc(sizeof(*fpu), GFP_KERNEL);
1637 if (!fpu)
1638 goto cleanup;
1639 #ifdef ELF_CORE_COPY_XFPREGS
1640 xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL);
1641 if (!xfpu)
1642 goto cleanup;
1643 #endif
1644
1645 if (signr) {
1646 struct core_thread *ct;
1647 struct elf_thread_status *tmp;
1648
1649 for (ct = current->mm->core_state->dumper.next;
1650 ct; ct = ct->next) {
1651 tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
1652 if (!tmp)
1653 goto cleanup;
1654
1655 tmp->thread = ct->task;
1656 list_add(&tmp->list, &thread_list);
1657 }
1658
1659 list_for_each(t, &thread_list) {
1660 struct elf_thread_status *tmp;
1661 int sz;
1662
1663 tmp = list_entry(t, struct elf_thread_status, list);
1664 sz = elf_dump_thread_status(signr, tmp);
1665 thread_status_size += sz;
1666 }
1667 }
1668
1669 /* now collect the dump for the current */
1670 fill_prstatus(prstatus, current, signr);
1671 elf_core_copy_regs(&prstatus->pr_reg, regs);
1672
1673 segs = current->mm->map_count;
1674 #ifdef ELF_CORE_EXTRA_PHDRS
1675 segs += ELF_CORE_EXTRA_PHDRS;
1676 #endif
1677
1678 /* Set up header */
1679 fill_elf_fdpic_header(elf, segs + 1); /* including notes section */
1680
1681 has_dumped = 1;
1682 current->flags |= PF_DUMPCORE;
1683
1684 /*
1685 * Set up the notes in similar form to SVR4 core dumps made
1686 * with info from their /proc.
1687 */
1688
1689 fill_note(notes + 0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus);
1690 fill_psinfo(psinfo, current->group_leader, current->mm);
1691 fill_note(notes + 1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1692
1693 numnote = 2;
1694
1695 auxv = (elf_addr_t *) current->mm->saved_auxv;
1696
1697 i = 0;
1698 do
1699 i += 2;
1700 while (auxv[i - 2] != AT_NULL);
1701 fill_note(&notes[numnote++], "CORE", NT_AUXV,
1702 i * sizeof(elf_addr_t), auxv);
1703
1704 /* Try to dump the FPU. */
1705 if ((prstatus->pr_fpvalid =
1706 elf_core_copy_task_fpregs(current, regs, fpu)))
1707 fill_note(notes + numnote++,
1708 "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
1709 #ifdef ELF_CORE_COPY_XFPREGS
1710 if (elf_core_copy_task_xfpregs(current, xfpu))
1711 fill_note(notes + numnote++,
1712 "LINUX", ELF_CORE_XFPREG_TYPE, sizeof(*xfpu), xfpu);
1713 #endif
1714
1715 fs = get_fs();
1716 set_fs(KERNEL_DS);
1717
1718 DUMP_WRITE(elf, sizeof(*elf));
1719 offset += sizeof(*elf); /* Elf header */
1720 offset += (segs+1) * sizeof(struct elf_phdr); /* Program headers */
1721
1722 /* Write notes phdr entry */
1723 {
1724 struct elf_phdr phdr;
1725 int sz = 0;
1726
1727 for (i = 0; i < numnote; i++)
1728 sz += notesize(notes + i);
1729
1730 sz += thread_status_size;
1731
1732 fill_elf_note_phdr(&phdr, sz, offset);
1733 offset += sz;
1734 DUMP_WRITE(&phdr, sizeof(phdr));
1735 }
1736
1737 /* Page-align dumped data */
1738 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1739
1740 /*
1741 * We must use the same mm->flags while dumping core to avoid
1742 * inconsistency between the program headers and bodies, otherwise an
1743 * unusable core file can be generated.
1744 */
1745 mm_flags = current->mm->flags;
1746
1747 /* write program headers for segments dump */
1748 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
1749 struct elf_phdr phdr;
1750 size_t sz;
1751
1752 sz = vma->vm_end - vma->vm_start;
1753
1754 phdr.p_type = PT_LOAD;
1755 phdr.p_offset = offset;
1756 phdr.p_vaddr = vma->vm_start;
1757 phdr.p_paddr = 0;
1758 phdr.p_filesz = maydump(vma, mm_flags) ? sz : 0;
1759 phdr.p_memsz = sz;
1760 offset += phdr.p_filesz;
1761 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
1762 if (vma->vm_flags & VM_WRITE)
1763 phdr.p_flags |= PF_W;
1764 if (vma->vm_flags & VM_EXEC)
1765 phdr.p_flags |= PF_X;
1766 phdr.p_align = ELF_EXEC_PAGESIZE;
1767
1768 DUMP_WRITE(&phdr, sizeof(phdr));
1769 }
1770
1771 #ifdef ELF_CORE_WRITE_EXTRA_PHDRS
1772 ELF_CORE_WRITE_EXTRA_PHDRS;
1773 #endif
1774
1775 /* write out the notes section */
1776 for (i = 0; i < numnote; i++)
1777 if (!writenote(notes + i, file))
1778 goto end_coredump;
1779
1780 /* write out the thread status notes section */
1781 list_for_each(t, &thread_list) {
1782 struct elf_thread_status *tmp =
1783 list_entry(t, struct elf_thread_status, list);
1784
1785 for (i = 0; i < tmp->num_notes; i++)
1786 if (!writenote(&tmp->notes[i], file))
1787 goto end_coredump;
1788 }
1789
1790 if (!dump_seek(file, dataoff))
1791 goto end_coredump;
1792
1793 if (elf_fdpic_dump_segments(file, &size, &limit, mm_flags) < 0)
1794 goto end_coredump;
1795
1796 #ifdef ELF_CORE_WRITE_EXTRA_DATA
1797 ELF_CORE_WRITE_EXTRA_DATA;
1798 #endif
1799
1800 if (file->f_pos != offset) {
1801 /* Sanity check */
1802 printk(KERN_WARNING
1803 "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n",
1804 file->f_pos, offset);
1805 }
1806
1807 end_coredump:
1808 set_fs(fs);
1809
1810 cleanup:
1811 while (!list_empty(&thread_list)) {
1812 struct list_head *tmp = thread_list.next;
1813 list_del(tmp);
1814 kfree(list_entry(tmp, struct elf_thread_status, list));
1815 }
1816
1817 kfree(elf);
1818 kfree(prstatus);
1819 kfree(psinfo);
1820 kfree(notes);
1821 kfree(fpu);
1822 #ifdef ELF_CORE_COPY_XFPREGS
1823 kfree(xfpu);
1824 #endif
1825 return has_dumped;
1826 #undef NUM_NOTES
1827 }
1828
1829 #endif /* USE_ELF_CORE_DUMP */
x86 "subsystem" repository