blob: 70e2999178984dbcf6af731189244a405a171830 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* binfmt_elf_fdpic.c: FDPIC ELF binary format
2 *
David Howells8a2ab7f2006-07-10 04:44:53 -07003 * Copyright (C) 2003, 2004, 2006 Red Hat, Inc. All Rights Reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 * 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>
David Howells6d8c4e32006-07-10 04:44:55 -070027#include <linux/pagemap.h>
Paul Mundt5edc2a52008-10-15 22:04:16 -070028#include <linux/security.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/highmem.h>
David Howells6d8c4e32006-07-10 04:44:55 -070030#include <linux/highuid.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <linux/personality.h>
32#include <linux/ptrace.h>
33#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/elf.h>
35#include <linux/elf-fdpic.h>
36#include <linux/elfcore.h>
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -080037#include <linux/coredump.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#include <asm/uaccess.h>
40#include <asm/param.h>
41#include <asm/pgalloc.h>
42
43typedef char *elf_caddr_t;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
45#if 0
46#define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
47#else
48#define kdebug(fmt, ...) do {} while(0)
49#endif
50
David Howells6d8c4e32006-07-10 04:44:55 -070051#if 0
52#define kdcore(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
53#else
54#define kdcore(fmt, ...) do {} while(0)
55#endif
56
Linus Torvalds1da177e2005-04-16 15:20:36 -070057MODULE_LICENSE("GPL");
58
Al Viro71613c32012-10-20 22:00:48 -040059static int load_elf_fdpic_binary(struct linux_binprm *);
David Howells8a2ab7f2006-07-10 04:44:53 -070060static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *, struct file *);
61static int elf_fdpic_map_file(struct elf_fdpic_params *, struct file *,
62 struct mm_struct *, const char *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
David Howells8a2ab7f2006-07-10 04:44:53 -070064static int create_elf_fdpic_tables(struct linux_binprm *, struct mm_struct *,
65 struct elf_fdpic_params *,
66 struct elf_fdpic_params *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
68#ifndef CONFIG_MMU
David Howells8a2ab7f2006-07-10 04:44:53 -070069static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *,
70 unsigned long *);
71static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *,
72 struct file *,
73 struct mm_struct *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070074#endif
75
David Howells8a2ab7f2006-07-10 04:44:53 -070076static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *,
77 struct file *, struct mm_struct *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
Christoph Hellwig698ba7b2009-12-15 16:47:37 -080079#ifdef CONFIG_ELF_CORE
Masami Hiramatsuf6151df2009-12-17 15:27:16 -080080static int elf_fdpic_core_dump(struct coredump_params *cprm);
David Howells6d8c4e32006-07-10 04:44:55 -070081#endif
82
Linus Torvalds1da177e2005-04-16 15:20:36 -070083static struct linux_binfmt elf_fdpic_format = {
84 .module = THIS_MODULE,
85 .load_binary = load_elf_fdpic_binary,
Christoph Hellwig698ba7b2009-12-15 16:47:37 -080086#ifdef CONFIG_ELF_CORE
David Howells6d8c4e32006-07-10 04:44:55 -070087 .core_dump = elf_fdpic_core_dump,
88#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 .min_coredump = ELF_EXEC_PAGESIZE,
90};
91
David Howells8a2ab7f2006-07-10 04:44:53 -070092static int __init init_elf_fdpic_binfmt(void)
93{
Al Viro8fc3dc52012-03-17 03:05:16 -040094 register_binfmt(&elf_fdpic_format);
95 return 0;
David Howells8a2ab7f2006-07-10 04:44:53 -070096}
Linus Torvalds1da177e2005-04-16 15:20:36 -070097
David Howells8a2ab7f2006-07-10 04:44:53 -070098static void __exit exit_elf_fdpic_binfmt(void)
99{
100 unregister_binfmt(&elf_fdpic_format);
101}
102
David Howells6d8c4e32006-07-10 04:44:55 -0700103core_initcall(init_elf_fdpic_binfmt);
David Howells8a2ab7f2006-07-10 04:44:53 -0700104module_exit(exit_elf_fdpic_binfmt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105
106static int is_elf_fdpic(struct elfhdr *hdr, struct file *file)
107{
108 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0)
109 return 0;
110 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)
111 return 0;
112 if (!elf_check_arch(hdr) || !elf_check_fdpic(hdr))
113 return 0;
Al Viro72c2d532013-09-22 16:27:52 -0400114 if (!file->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 return 0;
116 return 1;
117}
118
119/*****************************************************************************/
120/*
121 * read the program headers table into memory
122 */
David Howells8a2ab7f2006-07-10 04:44:53 -0700123static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params,
124 struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125{
126 struct elf32_phdr *phdr;
127 unsigned long size;
128 int retval, loop;
129
130 if (params->hdr.e_phentsize != sizeof(struct elf_phdr))
131 return -ENOMEM;
132 if (params->hdr.e_phnum > 65536U / sizeof(struct elf_phdr))
133 return -ENOMEM;
134
135 size = params->hdr.e_phnum * sizeof(struct elf_phdr);
136 params->phdrs = kmalloc(size, GFP_KERNEL);
137 if (!params->phdrs)
138 return -ENOMEM;
139
David Howells8a2ab7f2006-07-10 04:44:53 -0700140 retval = kernel_read(file, params->hdr.e_phoff,
141 (char *) params->phdrs, size);
David Howellse1d2c8b2008-04-29 00:59:34 -0700142 if (unlikely(retval != size))
143 return retval < 0 ? retval : -ENOEXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144
145 /* determine stack size for this binary */
146 phdr = params->phdrs;
147 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
148 if (phdr->p_type != PT_GNU_STACK)
149 continue;
150
151 if (phdr->p_flags & PF_X)
152 params->flags |= ELF_FDPIC_FLAG_EXEC_STACK;
153 else
154 params->flags |= ELF_FDPIC_FLAG_NOEXEC_STACK;
155
156 params->stack_size = phdr->p_memsz;
157 break;
158 }
159
160 return 0;
David Howells8a2ab7f2006-07-10 04:44:53 -0700161}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
163/*****************************************************************************/
164/*
165 * load an fdpic binary into various bits of memory
166 */
Al Viro71613c32012-10-20 22:00:48 -0400167static int load_elf_fdpic_binary(struct linux_binprm *bprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168{
169 struct elf_fdpic_params exec_params, interp_params;
Al Viro71613c32012-10-20 22:00:48 -0400170 struct pt_regs *regs = current_pt_regs();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 struct elf_phdr *phdr;
David Howells8a2ab7f2006-07-10 04:44:53 -0700172 unsigned long stack_size, entryaddr;
David Howells8a2ab7f2006-07-10 04:44:53 -0700173#ifdef ELF_FDPIC_PLAT_INIT
174 unsigned long dynaddr;
175#endif
Mike Frysinger04e4f2b2010-01-06 17:23:17 +0000176#ifndef CONFIG_MMU
177 unsigned long stack_prot;
178#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 struct file *interpreter = NULL; /* to shut gcc up */
180 char *interpreter_name = NULL;
181 int executable_stack;
182 int retval, i;
183
David Howellsaa289b42007-03-23 00:10:00 -0700184 kdebug("____ LOAD %d ____", current->pid);
185
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 memset(&exec_params, 0, sizeof(exec_params));
187 memset(&interp_params, 0, sizeof(interp_params));
188
189 exec_params.hdr = *(struct elfhdr *) bprm->buf;
190 exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE;
191
192 /* check that this is a binary we know how to deal with */
193 retval = -ENOEXEC;
194 if (!is_elf_fdpic(&exec_params.hdr, bprm->file))
195 goto error;
196
197 /* read the program header table */
198 retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);
199 if (retval < 0)
200 goto error;
201
202 /* scan for a program header that specifies an interpreter */
203 phdr = exec_params.phdrs;
204
205 for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) {
206 switch (phdr->p_type) {
207 case PT_INTERP:
208 retval = -ENOMEM;
209 if (phdr->p_filesz > PATH_MAX)
210 goto error;
211 retval = -ENOENT;
212 if (phdr->p_filesz < 2)
213 goto error;
214
215 /* read the name of the interpreter into memory */
Jesper Juhl792db3a2006-01-09 20:54:45 -0800216 interpreter_name = kmalloc(phdr->p_filesz, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 if (!interpreter_name)
218 goto error;
219
220 retval = kernel_read(bprm->file,
221 phdr->p_offset,
222 interpreter_name,
223 phdr->p_filesz);
David Howellse1d2c8b2008-04-29 00:59:34 -0700224 if (unlikely(retval != phdr->p_filesz)) {
225 if (retval >= 0)
226 retval = -ENOEXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 goto error;
David Howellse1d2c8b2008-04-29 00:59:34 -0700228 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229
230 retval = -ENOENT;
231 if (interpreter_name[phdr->p_filesz - 1] != '\0')
232 goto error;
233
234 kdebug("Using ELF interpreter %s", interpreter_name);
235
236 /* replace the program with the interpreter */
237 interpreter = open_exec(interpreter_name);
238 retval = PTR_ERR(interpreter);
239 if (IS_ERR(interpreter)) {
240 interpreter = NULL;
241 goto error;
242 }
243
Alexey Dobriyan1fb84492007-01-26 00:57:16 -0800244 /*
245 * If the binary is not readable then enforce
246 * mm->dumpable = 0 regardless of the interpreter's
247 * permissions.
248 */
Al Viro1b5d7832011-06-19 12:49:47 -0400249 would_dump(bprm, interpreter);
Alexey Dobriyan1fb84492007-01-26 00:57:16 -0800250
David Howells8a2ab7f2006-07-10 04:44:53 -0700251 retval = kernel_read(interpreter, 0, bprm->buf,
252 BINPRM_BUF_SIZE);
David Howellse1d2c8b2008-04-29 00:59:34 -0700253 if (unlikely(retval != BINPRM_BUF_SIZE)) {
254 if (retval >= 0)
255 retval = -ENOEXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 goto error;
David Howellse1d2c8b2008-04-29 00:59:34 -0700257 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258
259 interp_params.hdr = *((struct elfhdr *) bprm->buf);
260 break;
261
262 case PT_LOAD:
263#ifdef CONFIG_MMU
264 if (exec_params.load_addr == 0)
265 exec_params.load_addr = phdr->p_vaddr;
266#endif
267 break;
268 }
269
270 }
271
272 if (elf_check_const_displacement(&exec_params.hdr))
273 exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
274
275 /* perform insanity checks on the interpreter */
276 if (interpreter_name) {
277 retval = -ELIBBAD;
278 if (!is_elf_fdpic(&interp_params.hdr, interpreter))
279 goto error;
280
281 interp_params.flags = ELF_FDPIC_FLAG_PRESENT;
282
283 /* read the interpreter's program header table */
284 retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter);
285 if (retval < 0)
286 goto error;
287 }
288
289 stack_size = exec_params.stack_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
291 executable_stack = EXSTACK_ENABLE_X;
292 else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
293 executable_stack = EXSTACK_DISABLE_X;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 else
295 executable_stack = EXSTACK_DEFAULT;
296
David Howells8e8b63a2009-09-23 15:57:06 -0700297 if (stack_size == 0) {
298 stack_size = interp_params.stack_size;
299 if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
300 executable_stack = EXSTACK_ENABLE_X;
301 else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
302 executable_stack = EXSTACK_DISABLE_X;
303 else
304 executable_stack = EXSTACK_DEFAULT;
305 }
306
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 retval = -ENOEXEC;
308 if (stack_size == 0)
309 goto error;
310
311 if (elf_check_const_displacement(&interp_params.hdr))
312 interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
313
314 /* flush all traces of the currently running executable */
315 retval = flush_old_exec(bprm);
316 if (retval)
317 goto error;
318
319 /* there's now no turning back... the old userspace image is dead,
320 * defunct, deceased, etc. after this point we have to exit via
321 * error_kill */
322 set_personality(PER_LINUX_FDPIC);
Mike Frysinger04e4f2b2010-01-06 17:23:17 +0000323 if (elf_read_implies_exec(&exec_params.hdr, executable_stack))
324 current->personality |= READ_IMPLIES_EXEC;
Linus Torvalds221af7f2010-01-28 22:14:42 -0800325
326 setup_new_exec(bprm);
327
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 set_binfmt(&elf_fdpic_format);
329
330 current->mm->start_code = 0;
331 current->mm->end_code = 0;
332 current->mm->start_stack = 0;
333 current->mm->start_data = 0;
334 current->mm->end_data = 0;
335 current->mm->context.exec_fdpic_loadmap = 0;
336 current->mm->context.interp_fdpic_loadmap = 0;
337
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338#ifdef CONFIG_MMU
339 elf_fdpic_arch_lay_out_mm(&exec_params,
340 &interp_params,
341 &current->mm->start_stack,
342 &current->mm->start_brk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343
David Howells8a2ab7f2006-07-10 04:44:53 -0700344 retval = setup_arg_pages(bprm, current->mm->start_stack,
345 executable_stack);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 if (retval < 0) {
347 send_sig(SIGKILL, current, 0);
348 goto error_kill;
349 }
350#endif
351
352 /* load the executable and interpreter into memory */
David Howells8a2ab7f2006-07-10 04:44:53 -0700353 retval = elf_fdpic_map_file(&exec_params, bprm->file, current->mm,
354 "executable");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 if (retval < 0)
356 goto error_kill;
357
358 if (interpreter_name) {
359 retval = elf_fdpic_map_file(&interp_params, interpreter,
360 current->mm, "interpreter");
361 if (retval < 0) {
362 printk(KERN_ERR "Unable to load interpreter\n");
363 goto error_kill;
364 }
365
366 allow_write_access(interpreter);
367 fput(interpreter);
368 interpreter = NULL;
369 }
370
371#ifdef CONFIG_MMU
372 if (!current->mm->start_brk)
373 current->mm->start_brk = current->mm->end_data;
374
David Howells8a2ab7f2006-07-10 04:44:53 -0700375 current->mm->brk = current->mm->start_brk =
376 PAGE_ALIGN(current->mm->start_brk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
378#else
379 /* create a stack and brk area big enough for everyone
380 * - the brk heap starts at the bottom and works up
381 * - the stack starts at the top and works down
382 */
383 stack_size = (stack_size + PAGE_SIZE - 1) & PAGE_MASK;
384 if (stack_size < PAGE_SIZE * 2)
385 stack_size = PAGE_SIZE * 2;
386
Mike Frysinger04e4f2b2010-01-06 17:23:17 +0000387 stack_prot = PROT_READ | PROT_WRITE;
388 if (executable_stack == EXSTACK_ENABLE_X ||
389 (executable_stack == EXSTACK_DEFAULT && VM_STACK_FLAGS & VM_EXEC))
390 stack_prot |= PROT_EXEC;
391
Linus Torvalds6be5ceb2012-04-20 17:13:58 -0700392 current->mm->start_brk = vm_mmap(NULL, 0, stack_size, stack_prot,
Jie Zhangea637632009-12-14 18:00:02 -0800393 MAP_PRIVATE | MAP_ANONYMOUS |
394 MAP_UNINITIALIZED | MAP_GROWSDOWN,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395 0);
396
David Howells8a2ab7f2006-07-10 04:44:53 -0700397 if (IS_ERR_VALUE(current->mm->start_brk)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 retval = current->mm->start_brk;
399 current->mm->start_brk = 0;
400 goto error_kill;
401 }
402
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 current->mm->brk = current->mm->start_brk;
404 current->mm->context.end_brk = current->mm->start_brk;
David Howells8a2ab7f2006-07-10 04:44:53 -0700405 current->mm->context.end_brk +=
406 (stack_size > PAGE_SIZE) ? (stack_size - PAGE_SIZE) : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 current->mm->start_stack = current->mm->start_brk + stack_size;
408#endif
409
David Howellsa6f76f22008-11-14 10:39:24 +1100410 install_exec_creds(bprm);
David Howells8a2ab7f2006-07-10 04:44:53 -0700411 if (create_elf_fdpic_tables(bprm, current->mm,
412 &exec_params, &interp_params) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 goto error_kill;
414
David Howells8a2ab7f2006-07-10 04:44:53 -0700415 kdebug("- start_code %lx", current->mm->start_code);
416 kdebug("- end_code %lx", current->mm->end_code);
417 kdebug("- start_data %lx", current->mm->start_data);
418 kdebug("- end_data %lx", current->mm->end_data);
419 kdebug("- start_brk %lx", current->mm->start_brk);
420 kdebug("- brk %lx", current->mm->brk);
421 kdebug("- start_stack %lx", current->mm->start_stack);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422
423#ifdef ELF_FDPIC_PLAT_INIT
424 /*
425 * The ABI may specify that certain registers be set up in special
426 * ways (on i386 %edx is the address of a DT_FINI function, for
427 * example. This macro performs whatever initialization to
428 * the regs structure is required.
429 */
David Howells8a2ab7f2006-07-10 04:44:53 -0700430 dynaddr = interp_params.dynamic_addr ?: exec_params.dynamic_addr;
431 ELF_FDPIC_PLAT_INIT(regs, exec_params.map_addr, interp_params.map_addr,
432 dynaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433#endif
434
435 /* everything is now ready... get the userspace context ready to roll */
David Howells8a2ab7f2006-07-10 04:44:53 -0700436 entryaddr = interp_params.entry_addr ?: exec_params.entry_addr;
437 start_thread(regs, entryaddr, current->mm->start_stack);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439 retval = 0;
440
441error:
442 if (interpreter) {
443 allow_write_access(interpreter);
444 fput(interpreter);
445 }
Jesper Juhlf99d49a2005-11-07 01:01:34 -0800446 kfree(interpreter_name);
447 kfree(exec_params.phdrs);
448 kfree(exec_params.loadmap);
449 kfree(interp_params.phdrs);
450 kfree(interp_params.loadmap);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451 return retval;
452
453 /* unrecoverable error - kill the process */
David Howells8a2ab7f2006-07-10 04:44:53 -0700454error_kill:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 send_sig(SIGSEGV, current, 0);
456 goto error;
457
David Howells8a2ab7f2006-07-10 04:44:53 -0700458}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459
460/*****************************************************************************/
Paul Mundtec238472008-10-15 22:04:15 -0700461
462#ifndef ELF_BASE_PLATFORM
463/*
464 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
465 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
466 * will be copied to the user stack in the same manner as AT_PLATFORM.
467 */
468#define ELF_BASE_PLATFORM NULL
469#endif
470
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471/*
Paul Mundtc7637942008-10-15 22:04:15 -0700472 * present useful information to the program by shovelling it onto the new
473 * process's stack
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 */
475static int create_elf_fdpic_tables(struct linux_binprm *bprm,
476 struct mm_struct *mm,
477 struct elf_fdpic_params *exec_params,
478 struct elf_fdpic_params *interp_params)
479{
David Howells86a264a2008-11-14 10:39:18 +1100480 const struct cred *cred = current_cred();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 unsigned long sp, csp, nitems;
Al Viro530018b2006-06-23 02:04:05 -0700482 elf_caddr_t __user *argv, *envp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483 size_t platform_len = 0, len;
Paul Mundtec238472008-10-15 22:04:15 -0700484 char *k_platform, *k_base_platform;
485 char __user *u_platform, *u_base_platform, *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 int loop;
Paul Mundt9b14ec32008-05-19 13:34:45 +0900487 int nr; /* reset for each csp adjustment */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489#ifdef CONFIG_MMU
Paul Mundtc7637942008-10-15 22:04:15 -0700490 /* In some cases (e.g. Hyper-Threading), we want to avoid L1 evictions
491 * by the processes running on the same package. One thing we can do is
492 * to shuffle the initial stack for them, so we give the architecture
493 * an opportunity to do so here.
494 */
495 sp = arch_align_stack(bprm->p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496#else
497 sp = mm->start_stack;
498
499 /* stack the program arguments and environment */
500 if (elf_fdpic_transfer_args_to_stack(bprm, &sp) < 0)
501 return -EFAULT;
502#endif
503
Paul Mundtec238472008-10-15 22:04:15 -0700504 /*
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 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 k_platform = ELF_PLATFORM;
David Howells1aeb21d2006-07-10 04:44:50 -0700511 u_platform = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512
513 if (k_platform) {
514 platform_len = strlen(k_platform) + 1;
515 sp -= platform_len;
Al Viro530018b2006-06-23 02:04:05 -0700516 u_platform = (char __user *) sp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 if (__copy_to_user(u_platform, k_platform, platform_len) != 0)
518 return -EFAULT;
519 }
520
Paul Mundtec238472008-10-15 22:04:15 -0700521 /*
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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 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
Al Viro530018b2006-06-23 02:04:05 -0700544 if (copy_to_user((void __user *) sp, exec_params->loadmap, len) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 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);
David Howells8a2ab7f2006-07-10 04:44:53 -0700551 len += sizeof(struct elf32_fdpic_loadseg) *
552 interp_params->loadmap->nsegs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 sp = (sp - len) & ~7UL;
554 interp_params->map_addr = sp;
555
David Howells8a2ab7f2006-07-10 04:44:53 -0700556 if (copy_to_user((void __user *) sp, interp_params->loadmap,
557 len) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 return -EFAULT;
559
560 current->mm->context.interp_fdpic_loadmap = (unsigned long) sp;
561 }
562
563 /* force 16 byte _final_ alignment here for generality */
Paul Mundt5edc2a52008-10-15 22:04:16 -0700564#define DLINFO_ITEMS 15
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565
Paul Mundtec238472008-10-15 22:04:15 -0700566 nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) +
567 (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568
Paul Mundt5edc2a52008-10-15 22:04:16 -0700569 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD)
570 nitems++;
571
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 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 */
Paul Mundt9b14ec32008-05-19 13:34:45 +0900582#define NEW_AUX_ENT(id, val) \
David Howells8a2ab7f2006-07-10 04:44:53 -0700583 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); \
Paul Mundt9b14ec32008-05-19 13:34:45 +0900589 nr++; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 } while (0)
591
Paul Mundt9b14ec32008-05-19 13:34:45 +0900592 nr = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 csp -= 2 * sizeof(unsigned long);
Paul Mundt9b14ec32008-05-19 13:34:45 +0900594 NEW_AUX_ENT(AT_NULL, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595 if (k_platform) {
Paul Mundt9b14ec32008-05-19 13:34:45 +0900596 nr = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 csp -= 2 * sizeof(unsigned long);
Paul Mundt9b14ec32008-05-19 13:34:45 +0900598 NEW_AUX_ENT(AT_PLATFORM,
David Howells8a2ab7f2006-07-10 04:44:53 -0700599 (elf_addr_t) (unsigned long) u_platform);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 }
601
Paul Mundtec238472008-10-15 22:04:15 -0700602 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
Paul Mundt5edc2a52008-10-15 22:04:16 -0700609 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
Paul Mundt9b14ec32008-05-19 13:34:45 +0900615 nr = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616 csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long);
Michael Neuling21713642013-04-17 17:33:11 +0000617 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
618#ifdef ELF_HWCAP2
619 NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);
620#endif
Paul Mundt9b14ec32008-05-19 13:34:45 +0900621 NEW_AUX_ENT(AT_PAGESZ, PAGE_SIZE);
622 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
623 NEW_AUX_ENT(AT_PHDR, exec_params->ph_addr);
624 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
625 NEW_AUX_ENT(AT_PHNUM, exec_params->hdr.e_phnum);
626 NEW_AUX_ENT(AT_BASE, interp_params->elfhdr_addr);
627 NEW_AUX_ENT(AT_FLAGS, 0);
628 NEW_AUX_ENT(AT_ENTRY, exec_params->entry_addr);
Eric W. Biedermanebc887b2012-02-07 18:36:10 -0800629 NEW_AUX_ENT(AT_UID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->uid));
630 NEW_AUX_ENT(AT_EUID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->euid));
631 NEW_AUX_ENT(AT_GID, (elf_addr_t) from_kgid_munged(cred->user_ns, cred->gid));
632 NEW_AUX_ENT(AT_EGID, (elf_addr_t) from_kgid_munged(cred->user_ns, cred->egid));
Paul Mundt5edc2a52008-10-15 22:04:16 -0700633 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
634 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635
636#ifdef ARCH_DLINFO
Paul Mundt9b14ec32008-05-19 13:34:45 +0900637 nr = 0;
638 csp -= AT_VECTOR_SIZE_ARCH * 2 * sizeof(unsigned long);
639
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 /* ARCH_DLINFO must come last so platform specific code can enforce
641 * special alignment requirements on the AUXV if necessary (eg. PPC).
642 */
643 ARCH_DLINFO;
644#endif
645#undef NEW_AUX_ENT
646
647 /* allocate room for argv[] and envv[] */
648 csp -= (bprm->envc + 1) * sizeof(elf_caddr_t);
Al Viro530018b2006-06-23 02:04:05 -0700649 envp = (elf_caddr_t __user *) csp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 csp -= (bprm->argc + 1) * sizeof(elf_caddr_t);
Al Viro530018b2006-06-23 02:04:05 -0700651 argv = (elf_caddr_t __user *) csp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652
653 /* stack argc */
654 csp -= sizeof(unsigned long);
Al Viro530018b2006-06-23 02:04:05 -0700655 __put_user(bprm->argc, (unsigned long __user *) csp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656
Eric Sesterhenn88bcd512006-03-24 18:38:48 +0100657 BUG_ON(csp != sp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658
659 /* fill in the argv[] array */
660#ifdef CONFIG_MMU
661 current->mm->arg_start = bprm->p;
662#else
David Howells8a2ab7f2006-07-10 04:44:53 -0700663 current->mm->arg_start = current->mm->start_stack -
664 (MAX_ARG_PAGES * PAGE_SIZE - bprm->p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665#endif
666
Al Viro530018b2006-06-23 02:04:05 -0700667 p = (char __user *) current->mm->arg_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 for (loop = bprm->argc; loop > 0; loop--) {
669 __put_user((elf_caddr_t) p, argv++);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700670 len = strnlen_user(p, MAX_ARG_STRLEN);
671 if (!len || len > MAX_ARG_STRLEN)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672 return -EINVAL;
673 p += len;
674 }
675 __put_user(NULL, argv);
676 current->mm->arg_end = (unsigned long) p;
677
678 /* fill in the envv[] array */
679 current->mm->env_start = (unsigned long) p;
680 for (loop = bprm->envc; loop > 0; loop--) {
681 __put_user((elf_caddr_t)(unsigned long) p, envp++);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700682 len = strnlen_user(p, MAX_ARG_STRLEN);
683 if (!len || len > MAX_ARG_STRLEN)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 return -EINVAL;
685 p += len;
686 }
687 __put_user(NULL, envp);
688 current->mm->env_end = (unsigned long) p;
689
690 mm->start_stack = (unsigned long) sp;
691 return 0;
David Howells8a2ab7f2006-07-10 04:44:53 -0700692}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693
694/*****************************************************************************/
695/*
696 * transfer the program arguments and environment from the holding pages onto
697 * the stack
698 */
699#ifndef CONFIG_MMU
David Howells8a2ab7f2006-07-10 04:44:53 -0700700static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *bprm,
701 unsigned long *_sp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702{
703 unsigned long index, stop, sp;
704 char *src;
705 int ret = 0;
706
707 stop = bprm->p >> PAGE_SHIFT;
708 sp = *_sp;
709
710 for (index = MAX_ARG_PAGES - 1; index >= stop; index--) {
711 src = kmap(bprm->page[index]);
712 sp -= PAGE_SIZE;
713 if (copy_to_user((void *) sp, src, PAGE_SIZE) != 0)
714 ret = -EFAULT;
715 kunmap(bprm->page[index]);
716 if (ret < 0)
717 goto out;
718 }
719
720 *_sp = (*_sp - (MAX_ARG_PAGES * PAGE_SIZE - bprm->p)) & ~15;
721
David Howells8a2ab7f2006-07-10 04:44:53 -0700722out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723 return ret;
David Howells8a2ab7f2006-07-10 04:44:53 -0700724}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725#endif
726
727/*****************************************************************************/
728/*
729 * load the appropriate binary image (executable or interpreter) into memory
730 * - we assume no MMU is available
731 * - if no other PIC bits are set in params->hdr->e_flags
732 * - we assume that the LOADable segments in the binary are independently relocatable
733 * - we assume R/O executable segments are shareable
734 * - else
735 * - we assume the loadable parts of the image to require fixed displacement
736 * - the image is not shareable
737 */
738static int elf_fdpic_map_file(struct elf_fdpic_params *params,
739 struct file *file,
740 struct mm_struct *mm,
741 const char *what)
742{
743 struct elf32_fdpic_loadmap *loadmap;
744#ifdef CONFIG_MMU
745 struct elf32_fdpic_loadseg *mseg;
746#endif
747 struct elf32_fdpic_loadseg *seg;
748 struct elf32_phdr *phdr;
749 unsigned long load_addr, stop;
750 unsigned nloads, tmp;
751 size_t size;
752 int loop, ret;
753
754 /* allocate a load map table */
755 nloads = 0;
756 for (loop = 0; loop < params->hdr.e_phnum; loop++)
757 if (params->phdrs[loop].p_type == PT_LOAD)
758 nloads++;
759
760 if (nloads == 0)
761 return -ELIBBAD;
762
763 size = sizeof(*loadmap) + nloads * sizeof(*seg);
Robert P. J. Dayb87576d2006-12-12 20:07:35 +0100764 loadmap = kzalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 if (!loadmap)
766 return -ENOMEM;
767
768 params->loadmap = loadmap;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769
770 loadmap->version = ELF32_FDPIC_LOADMAP_VERSION;
771 loadmap->nsegs = nloads;
772
773 load_addr = params->load_addr;
774 seg = loadmap->segs;
775
776 /* map the requested LOADs into the memory space */
777 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
778 case ELF_FDPIC_FLAG_CONSTDISP:
779 case ELF_FDPIC_FLAG_CONTIGUOUS:
780#ifndef CONFIG_MMU
781 ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm);
782 if (ret < 0)
783 return ret;
784 break;
785#endif
786 default:
787 ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm);
788 if (ret < 0)
789 return ret;
790 break;
791 }
792
793 /* map the entry point */
794 if (params->hdr.e_entry) {
795 seg = loadmap->segs;
796 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
797 if (params->hdr.e_entry >= seg->p_vaddr &&
David Howells8a2ab7f2006-07-10 04:44:53 -0700798 params->hdr.e_entry < seg->p_vaddr + seg->p_memsz) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799 params->entry_addr =
David Howells8a2ab7f2006-07-10 04:44:53 -0700800 (params->hdr.e_entry - seg->p_vaddr) +
801 seg->addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802 break;
803 }
804 }
805 }
806
807 /* determine where the program header table has wound up if mapped */
David Howells8a2ab7f2006-07-10 04:44:53 -0700808 stop = params->hdr.e_phoff;
809 stop += params->hdr.e_phnum * sizeof (struct elf_phdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 phdr = params->phdrs;
811
812 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
813 if (phdr->p_type != PT_LOAD)
814 continue;
815
816 if (phdr->p_offset > params->hdr.e_phoff ||
817 phdr->p_offset + phdr->p_filesz < stop)
818 continue;
819
820 seg = loadmap->segs;
821 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
822 if (phdr->p_vaddr >= seg->p_vaddr &&
David Howells8a2ab7f2006-07-10 04:44:53 -0700823 phdr->p_vaddr + phdr->p_filesz <=
824 seg->p_vaddr + seg->p_memsz) {
825 params->ph_addr =
826 (phdr->p_vaddr - seg->p_vaddr) +
827 seg->addr +
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 params->hdr.e_phoff - phdr->p_offset;
829 break;
830 }
831 }
832 break;
833 }
834
835 /* determine where the dynamic section has wound up if there is one */
836 phdr = params->phdrs;
837 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
838 if (phdr->p_type != PT_DYNAMIC)
839 continue;
840
841 seg = loadmap->segs;
842 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
843 if (phdr->p_vaddr >= seg->p_vaddr &&
David Howells8a2ab7f2006-07-10 04:44:53 -0700844 phdr->p_vaddr + phdr->p_memsz <=
845 seg->p_vaddr + seg->p_memsz) {
846 params->dynamic_addr =
847 (phdr->p_vaddr - seg->p_vaddr) +
848 seg->addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849
David Howells8a2ab7f2006-07-10 04:44:53 -0700850 /* check the dynamic section contains at least
851 * one item, and that the last item is a NULL
852 * entry */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853 if (phdr->p_memsz == 0 ||
854 phdr->p_memsz % sizeof(Elf32_Dyn) != 0)
855 goto dynamic_error;
856
857 tmp = phdr->p_memsz / sizeof(Elf32_Dyn);
David Howells8a2ab7f2006-07-10 04:44:53 -0700858 if (((Elf32_Dyn *)
859 params->dynamic_addr)[tmp - 1].d_tag != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860 goto dynamic_error;
861 break;
862 }
863 }
864 break;
865 }
866
867 /* now elide adjacent segments in the load map on MMU linux
David Howells8a2ab7f2006-07-10 04:44:53 -0700868 * - on uClinux the holes between may actually be filled with system
869 * stuff or stuff from other processes
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 */
871#ifdef CONFIG_MMU
872 nloads = loadmap->nsegs;
873 mseg = loadmap->segs;
874 seg = mseg + 1;
875 for (loop = 1; loop < nloads; loop++) {
876 /* see if we have a candidate for merging */
877 if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) {
878 load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz);
879 if (load_addr == (seg->addr & PAGE_MASK)) {
David Howells8a2ab7f2006-07-10 04:44:53 -0700880 mseg->p_memsz +=
881 load_addr -
882 (mseg->addr + mseg->p_memsz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883 mseg->p_memsz += seg->addr & ~PAGE_MASK;
884 mseg->p_memsz += seg->p_memsz;
885 loadmap->nsegs--;
886 continue;
887 }
888 }
889
890 mseg++;
891 if (mseg != seg)
892 *mseg = *seg;
893 }
894#endif
895
896 kdebug("Mapped Object [%s]:", what);
897 kdebug("- elfhdr : %lx", params->elfhdr_addr);
898 kdebug("- entry : %lx", params->entry_addr);
899 kdebug("- PHDR[] : %lx", params->ph_addr);
900 kdebug("- DYNAMIC[]: %lx", params->dynamic_addr);
901 seg = loadmap->segs;
902 for (loop = 0; loop < loadmap->nsegs; loop++, seg++)
903 kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]",
904 loop,
905 seg->addr, seg->addr + seg->p_memsz - 1,
906 seg->p_vaddr, seg->p_memsz);
907
908 return 0;
909
David Howells8a2ab7f2006-07-10 04:44:53 -0700910dynamic_error:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911 printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n",
Al Viro496ad9a2013-01-23 17:07:38 -0500912 what, file_inode(file)->i_ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913 return -ELIBBAD;
David Howells8a2ab7f2006-07-10 04:44:53 -0700914}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915
916/*****************************************************************************/
917/*
918 * map a file with constant displacement under uClinux
919 */
920#ifndef CONFIG_MMU
David Howells8a2ab7f2006-07-10 04:44:53 -0700921static int elf_fdpic_map_file_constdisp_on_uclinux(
922 struct elf_fdpic_params *params,
923 struct file *file,
924 struct mm_struct *mm)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925{
926 struct elf32_fdpic_loadseg *seg;
927 struct elf32_phdr *phdr;
928 unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929 int loop, ret;
930
931 load_addr = params->load_addr;
932 seg = params->loadmap->segs;
933
David Howells8a2ab7f2006-07-10 04:44:53 -0700934 /* determine the bounds of the contiguous overall allocation we must
935 * make */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936 phdr = params->phdrs;
937 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
938 if (params->phdrs[loop].p_type != PT_LOAD)
939 continue;
940
941 if (base > phdr->p_vaddr)
942 base = phdr->p_vaddr;
943 if (top < phdr->p_vaddr + phdr->p_memsz)
944 top = phdr->p_vaddr + phdr->p_memsz;
945 }
946
947 /* allocate one big anon block for everything */
948 mflags = MAP_PRIVATE;
949 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
950 mflags |= MAP_EXECUTABLE;
951
Linus Torvalds6be5ceb2012-04-20 17:13:58 -0700952 maddr = vm_mmap(NULL, load_addr, top - base,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953 PROT_READ | PROT_WRITE | PROT_EXEC, mflags, 0);
David Howells8a2ab7f2006-07-10 04:44:53 -0700954 if (IS_ERR_VALUE(maddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955 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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966 seg->addr = maddr + (phdr->p_vaddr - base);
967 seg->p_vaddr = phdr->p_vaddr;
968 seg->p_memsz = phdr->p_memsz;
969
Al Viro3dc20cb2013-04-13 20:31:37 -0400970 ret = read_code(file, seg->addr, phdr->p_offset,
971 phdr->p_filesz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972 if (ret < 0)
973 return ret;
974
975 /* map the ELF header address if in this segment */
976 if (phdr->p_offset == 0)
977 params->elfhdr_addr = seg->addr;
978
979 /* clear any space allocated but not loaded */
Mike Frysingerab4ad552009-04-02 16:58:28 -0700980 if (phdr->p_filesz < phdr->p_memsz) {
Takuya Yoshikawae30c7c32010-06-01 14:10:47 +0100981 if (clear_user((void *) (seg->addr + phdr->p_filesz),
982 phdr->p_memsz - phdr->p_filesz))
983 return -EFAULT;
Mike Frysingerab4ad552009-04-02 16:58:28 -0700984 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985
986 if (mm) {
987 if (phdr->p_flags & PF_X) {
David Howellsaa289b42007-03-23 00:10:00 -0700988 if (!mm->start_code) {
989 mm->start_code = seg->addr;
990 mm->end_code = seg->addr +
991 phdr->p_memsz;
992 }
David Howells8a2ab7f2006-07-10 04:44:53 -0700993 } else if (!mm->start_data) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994 mm->start_data = seg->addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 mm->end_data = seg->addr + phdr->p_memsz;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997 }
998
999 seg++;
1000 }
1001
1002 return 0;
David Howells8a2ab7f2006-07-10 04:44:53 -07001003}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004#endif
1005
1006/*****************************************************************************/
1007/*
1008 * map a binary by direct mmap() of the individual PT_LOAD segments
1009 */
1010static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
1011 struct file *file,
1012 struct mm_struct *mm)
1013{
1014 struct elf32_fdpic_loadseg *seg;
1015 struct elf32_phdr *phdr;
1016 unsigned long load_addr, delta_vaddr;
Takuya Yoshikawae30c7c32010-06-01 14:10:47 +01001017 int loop, dvset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018
1019 load_addr = params->load_addr;
1020 delta_vaddr = 0;
1021 dvset = 0;
1022
1023 seg = params->loadmap->segs;
1024
1025 /* deal with each load segment separately */
1026 phdr = params->phdrs;
1027 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
1028 unsigned long maddr, disp, excess, excess1;
1029 int prot = 0, flags;
1030
1031 if (phdr->p_type != PT_LOAD)
1032 continue;
1033
1034 kdebug("[LOAD] va=%lx of=%lx fs=%lx ms=%lx",
1035 (unsigned long) phdr->p_vaddr,
1036 (unsigned long) phdr->p_offset,
1037 (unsigned long) phdr->p_filesz,
1038 (unsigned long) phdr->p_memsz);
1039
1040 /* determine the mapping parameters */
1041 if (phdr->p_flags & PF_R) prot |= PROT_READ;
1042 if (phdr->p_flags & PF_W) prot |= PROT_WRITE;
1043 if (phdr->p_flags & PF_X) prot |= PROT_EXEC;
1044
1045 flags = MAP_PRIVATE | MAP_DENYWRITE;
1046 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
1047 flags |= MAP_EXECUTABLE;
1048
1049 maddr = 0;
1050
1051 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
1052 case ELF_FDPIC_FLAG_INDEPENDENT:
1053 /* PT_LOADs are independently locatable */
1054 break;
1055
1056 case ELF_FDPIC_FLAG_HONOURVADDR:
1057 /* the specified virtual address must be honoured */
1058 maddr = phdr->p_vaddr;
1059 flags |= MAP_FIXED;
1060 break;
1061
1062 case ELF_FDPIC_FLAG_CONSTDISP:
1063 /* constant displacement
David Howells8a2ab7f2006-07-10 04:44:53 -07001064 * - can be mapped anywhere, but must be mapped as a
1065 * unit
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066 */
1067 if (!dvset) {
1068 maddr = load_addr;
1069 delta_vaddr = phdr->p_vaddr;
1070 dvset = 1;
David Howells8a2ab7f2006-07-10 04:44:53 -07001071 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072 maddr = load_addr + phdr->p_vaddr - delta_vaddr;
1073 flags |= MAP_FIXED;
1074 }
1075 break;
1076
1077 case ELF_FDPIC_FLAG_CONTIGUOUS:
1078 /* contiguity handled later */
1079 break;
1080
1081 default:
1082 BUG();
1083 }
1084
1085 maddr &= PAGE_MASK;
1086
1087 /* create the mapping */
1088 disp = phdr->p_vaddr & ~PAGE_MASK;
Linus Torvalds6be5ceb2012-04-20 17:13:58 -07001089 maddr = vm_mmap(file, maddr, phdr->p_memsz + disp, prot, flags,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090 phdr->p_offset - disp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091
1092 kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx",
David Howells8a2ab7f2006-07-10 04:44:53 -07001093 loop, phdr->p_memsz + disp, prot, flags,
1094 phdr->p_offset - disp, maddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001095
David Howells8a2ab7f2006-07-10 04:44:53 -07001096 if (IS_ERR_VALUE(maddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097 return (int) maddr;
1098
David Howells8a2ab7f2006-07-10 04:44:53 -07001099 if ((params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) ==
1100 ELF_FDPIC_FLAG_CONTIGUOUS)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001101 load_addr += PAGE_ALIGN(phdr->p_memsz + disp);
1102
1103 seg->addr = maddr + disp;
1104 seg->p_vaddr = phdr->p_vaddr;
1105 seg->p_memsz = phdr->p_memsz;
1106
1107 /* map the ELF header address if in this segment */
1108 if (phdr->p_offset == 0)
1109 params->elfhdr_addr = seg->addr;
1110
David Howells8a2ab7f2006-07-10 04:44:53 -07001111 /* clear the bit between beginning of mapping and beginning of
1112 * PT_LOAD */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113 if (prot & PROT_WRITE && disp > 0) {
1114 kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp);
Takuya Yoshikawae30c7c32010-06-01 14:10:47 +01001115 if (clear_user((void __user *) maddr, disp))
1116 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117 maddr += disp;
1118 }
1119
1120 /* clear any space allocated but not loaded
1121 * - on uClinux we can just clear the lot
1122 * - on MMU linux we'll get a SIGBUS beyond the last page
1123 * extant in the file
1124 */
1125 excess = phdr->p_memsz - phdr->p_filesz;
1126 excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
1127
1128#ifdef CONFIG_MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -07001129 if (excess > excess1) {
1130 unsigned long xaddr = maddr + phdr->p_filesz + excess1;
1131 unsigned long xmaddr;
1132
1133 flags |= MAP_FIXED | MAP_ANONYMOUS;
Linus Torvalds6be5ceb2012-04-20 17:13:58 -07001134 xmaddr = vm_mmap(NULL, xaddr, excess - excess1,
David Howells8a2ab7f2006-07-10 04:44:53 -07001135 prot, flags, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136
1137 kdebug("mmap[%d] <anon>"
1138 " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",
David Howells8a2ab7f2006-07-10 04:44:53 -07001139 loop, xaddr, excess - excess1, prot, flags,
1140 xmaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141
1142 if (xmaddr != xaddr)
1143 return -ENOMEM;
1144 }
1145
1146 if (prot & PROT_WRITE && excess1 > 0) {
1147 kdebug("clear[%d] ad=%lx sz=%lx",
1148 loop, maddr + phdr->p_filesz, excess1);
Takuya Yoshikawae30c7c32010-06-01 14:10:47 +01001149 if (clear_user((void __user *) maddr + phdr->p_filesz,
1150 excess1))
1151 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 }
1153
1154#else
1155 if (excess > 0) {
1156 kdebug("clear[%d] ad=%lx sz=%lx",
1157 loop, maddr + phdr->p_filesz, excess);
Takuya Yoshikawae30c7c32010-06-01 14:10:47 +01001158 if (clear_user((void *) maddr + phdr->p_filesz, excess))
1159 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160 }
1161#endif
1162
1163 if (mm) {
1164 if (phdr->p_flags & PF_X) {
David Howellsaa289b42007-03-23 00:10:00 -07001165 if (!mm->start_code) {
1166 mm->start_code = maddr;
1167 mm->end_code = maddr + phdr->p_memsz;
1168 }
David Howells8a2ab7f2006-07-10 04:44:53 -07001169 } else if (!mm->start_data) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001170 mm->start_data = maddr;
1171 mm->end_data = maddr + phdr->p_memsz;
1172 }
1173 }
1174
1175 seg++;
1176 }
1177
1178 return 0;
David Howells8a2ab7f2006-07-10 04:44:53 -07001179}
David Howells6d8c4e32006-07-10 04:44:55 -07001180
1181/*****************************************************************************/
1182/*
1183 * ELF-FDPIC core dumper
1184 *
1185 * Modelled on fs/exec.c:aout_core_dump()
1186 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1187 *
1188 * Modelled on fs/binfmt_elf.c core dumper
1189 */
Christoph Hellwig698ba7b2009-12-15 16:47:37 -08001190#ifdef CONFIG_ELF_CORE
David Howells6d8c4e32006-07-10 04:44:55 -07001191
1192/*
David Howells6d8c4e32006-07-10 04:44:55 -07001193 * Decide whether a segment is worth dumping; default is yes to be
1194 * sure (missing info is worse than too much; etc).
1195 * Personally I'd include everything, and use the coredump limit...
1196 *
1197 * I think we should skip something. But I am not sure how. H.J.
1198 */
Kawai, Hidehiroee78b0a2007-07-19 01:48:30 -07001199static int maydump(struct vm_area_struct *vma, unsigned long mm_flags)
David Howells6d8c4e32006-07-10 04:44:55 -07001200{
Kawai, Hidehiroee78b0a2007-07-19 01:48:30 -07001201 int dump_ok;
1202
David Howells6d8c4e32006-07-10 04:44:55 -07001203 /* Do not dump I/O mapped devices or special mappings */
Konstantin Khlebnikov314e51b2012-10-08 16:29:02 -07001204 if (vma->vm_flags & VM_IO) {
David Howells6d8c4e32006-07-10 04:44:55 -07001205 kdcore("%08lx: %08lx: no (IO)", vma->vm_start, vma->vm_flags);
1206 return 0;
1207 }
1208
1209 /* If we may not read the contents, don't allow us to dump
1210 * them either. "dump_write()" can't handle it anyway.
1211 */
1212 if (!(vma->vm_flags & VM_READ)) {
1213 kdcore("%08lx: %08lx: no (!read)", vma->vm_start, vma->vm_flags);
1214 return 0;
1215 }
1216
Kawai, Hidehiroee78b0a2007-07-19 01:48:30 -07001217 /* By default, dump shared memory if mapped from an anonymous file. */
David Howells6d8c4e32006-07-10 04:44:55 -07001218 if (vma->vm_flags & VM_SHARED) {
Al Viro496ad9a2013-01-23 17:07:38 -05001219 if (file_inode(vma->vm_file)->i_nlink == 0) {
Kawai, Hidehiroee78b0a2007-07-19 01:48:30 -07001220 dump_ok = test_bit(MMF_DUMP_ANON_SHARED, &mm_flags);
1221 kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
1222 vma->vm_flags, dump_ok ? "yes" : "no");
1223 return dump_ok;
David Howells6d8c4e32006-07-10 04:44:55 -07001224 }
1225
Kawai, Hidehiroee78b0a2007-07-19 01:48:30 -07001226 dump_ok = test_bit(MMF_DUMP_MAPPED_SHARED, &mm_flags);
1227 kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
1228 vma->vm_flags, dump_ok ? "yes" : "no");
1229 return dump_ok;
David Howells6d8c4e32006-07-10 04:44:55 -07001230 }
1231
1232#ifdef CONFIG_MMU
Kawai, Hidehiroee78b0a2007-07-19 01:48:30 -07001233 /* By default, if it hasn't been written to, don't write it out */
David Howells6d8c4e32006-07-10 04:44:55 -07001234 if (!vma->anon_vma) {
Kawai, Hidehiroee78b0a2007-07-19 01:48:30 -07001235 dump_ok = test_bit(MMF_DUMP_MAPPED_PRIVATE, &mm_flags);
1236 kdcore("%08lx: %08lx: %s (!anon)", vma->vm_start,
1237 vma->vm_flags, dump_ok ? "yes" : "no");
1238 return dump_ok;
David Howells6d8c4e32006-07-10 04:44:55 -07001239 }
1240#endif
1241
Kawai, Hidehiroee78b0a2007-07-19 01:48:30 -07001242 dump_ok = test_bit(MMF_DUMP_ANON_PRIVATE, &mm_flags);
1243 kdcore("%08lx: %08lx: %s", vma->vm_start, vma->vm_flags,
1244 dump_ok ? "yes" : "no");
1245 return dump_ok;
David Howells6d8c4e32006-07-10 04:44:55 -07001246}
1247
1248/* An ELF note in memory */
1249struct memelfnote
1250{
1251 const char *name;
1252 int type;
1253 unsigned int datasz;
1254 void *data;
1255};
1256
1257static int notesize(struct memelfnote *en)
1258{
1259 int sz;
1260
1261 sz = sizeof(struct elf_note);
1262 sz += roundup(strlen(en->name) + 1, 4);
1263 sz += roundup(en->datasz, 4);
1264
1265 return sz;
1266}
1267
1268/* #define DEBUG */
1269
Al Viroe6c1baa2013-10-05 18:58:47 -04001270static int alignfile(struct coredump_params *cprm)
Daisuke HATAYAMA05f47fd2010-03-05 13:44:05 -08001271{
1272 static const char buf[4] = { 0, };
Al Viroe6c1baa2013-10-05 18:58:47 -04001273 return dump_emit(cprm, buf, roundup(cprm->written, 4) - cprm->written);
Daisuke HATAYAMA05f47fd2010-03-05 13:44:05 -08001274}
1275
Al Viroe6c1baa2013-10-05 18:58:47 -04001276static int writenote(struct memelfnote *men, struct coredump_params *cprm)
David Howells6d8c4e32006-07-10 04:44:55 -07001277{
1278 struct elf_note en;
David Howells6d8c4e32006-07-10 04:44:55 -07001279 en.n_namesz = strlen(men->name) + 1;
1280 en.n_descsz = men->datasz;
1281 en.n_type = men->type;
1282
Al Viroe6c1baa2013-10-05 18:58:47 -04001283 return dump_emit(cprm, &en, sizeof(en)) &&
1284 dump_emit(cprm, men->name, en.n_namesz) && alignfile(cprm) &&
1285 dump_emit(cprm, men->data, men->datasz) && alignfile(cprm);
David Howells6d8c4e32006-07-10 04:44:55 -07001286}
David Howells6d8c4e32006-07-10 04:44:55 -07001287
David Howells6d8c4e32006-07-10 04:44:55 -07001288static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)
1289{
1290 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1291 elf->e_ident[EI_CLASS] = ELF_CLASS;
1292 elf->e_ident[EI_DATA] = ELF_DATA;
1293 elf->e_ident[EI_VERSION] = EV_CURRENT;
1294 elf->e_ident[EI_OSABI] = ELF_OSABI;
1295 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
1296
1297 elf->e_type = ET_CORE;
1298 elf->e_machine = ELF_ARCH;
1299 elf->e_version = EV_CURRENT;
1300 elf->e_entry = 0;
1301 elf->e_phoff = sizeof(struct elfhdr);
1302 elf->e_shoff = 0;
1303 elf->e_flags = ELF_FDPIC_CORE_EFLAGS;
1304 elf->e_ehsize = sizeof(struct elfhdr);
1305 elf->e_phentsize = sizeof(struct elf_phdr);
1306 elf->e_phnum = segs;
1307 elf->e_shentsize = 0;
1308 elf->e_shnum = 0;
1309 elf->e_shstrndx = 0;
1310 return;
1311}
1312
1313static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
1314{
1315 phdr->p_type = PT_NOTE;
1316 phdr->p_offset = offset;
1317 phdr->p_vaddr = 0;
1318 phdr->p_paddr = 0;
1319 phdr->p_filesz = sz;
1320 phdr->p_memsz = 0;
1321 phdr->p_flags = 0;
1322 phdr->p_align = 0;
1323 return;
1324}
1325
1326static inline void fill_note(struct memelfnote *note, const char *name, int type,
1327 unsigned int sz, void *data)
1328{
1329 note->name = name;
1330 note->type = type;
1331 note->datasz = sz;
1332 note->data = data;
1333 return;
1334}
1335
1336/*
1337 * fill up all the fields in prstatus from the given task struct, except
Daniel Mack3ad2f3f2010-02-03 08:01:28 +08001338 * registers which need to be filled up separately.
David Howells6d8c4e32006-07-10 04:44:55 -07001339 */
1340static void fill_prstatus(struct elf_prstatus *prstatus,
1341 struct task_struct *p, long signr)
1342{
1343 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1344 prstatus->pr_sigpend = p->pending.signal.sig[0];
1345 prstatus->pr_sighold = p->blocked.sig[0];
Oleg Nesterov3b34fc52009-06-17 16:27:38 -07001346 rcu_read_lock();
1347 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1348 rcu_read_unlock();
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001349 prstatus->pr_pid = task_pid_vnr(p);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001350 prstatus->pr_pgrp = task_pgrp_vnr(p);
1351 prstatus->pr_sid = task_session_vnr(p);
David Howells6d8c4e32006-07-10 04:44:55 -07001352 if (thread_group_leader(p)) {
Paul Mundt2515ddc2008-10-21 12:07:40 +09001353 struct task_cputime cputime;
1354
David Howells6d8c4e32006-07-10 04:44:55 -07001355 /*
Paul Mundt2515ddc2008-10-21 12:07:40 +09001356 * This is the record for the group leader. It shows the
1357 * group-wide total, not its individual thread total.
David Howells6d8c4e32006-07-10 04:44:55 -07001358 */
Paul Mundt2515ddc2008-10-21 12:07:40 +09001359 thread_group_cputime(p, &cputime);
1360 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1361 cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
David Howells6d8c4e32006-07-10 04:44:55 -07001362 } else {
Frederic Weisbecker6fac4822012-11-13 14:20:55 +01001363 cputime_t utime, stime;
1364
1365 task_cputime(p, &utime, &stime);
1366 cputime_to_timeval(utime, &prstatus->pr_utime);
1367 cputime_to_timeval(stime, &prstatus->pr_stime);
David Howells6d8c4e32006-07-10 04:44:55 -07001368 }
1369 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1370 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1371
1372 prstatus->pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap;
1373 prstatus->pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap;
1374}
1375
1376static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1377 struct mm_struct *mm)
1378{
David Howellsc69e8d92008-11-14 10:39:19 +11001379 const struct cred *cred;
David Howells6d8c4e32006-07-10 04:44:55 -07001380 unsigned int i, len;
1381
1382 /* first copy the parameters from user space */
1383 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1384
1385 len = mm->arg_end - mm->arg_start;
1386 if (len >= ELF_PRARGSZ)
1387 len = ELF_PRARGSZ - 1;
1388 if (copy_from_user(&psinfo->pr_psargs,
1389 (const char __user *) mm->arg_start, len))
1390 return -EFAULT;
1391 for (i = 0; i < len; i++)
1392 if (psinfo->pr_psargs[i] == 0)
1393 psinfo->pr_psargs[i] = ' ';
1394 psinfo->pr_psargs[len] = 0;
1395
Oleg Nesterov3b34fc52009-06-17 16:27:38 -07001396 rcu_read_lock();
1397 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1398 rcu_read_unlock();
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001399 psinfo->pr_pid = task_pid_vnr(p);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001400 psinfo->pr_pgrp = task_pgrp_vnr(p);
1401 psinfo->pr_sid = task_session_vnr(p);
David Howells6d8c4e32006-07-10 04:44:55 -07001402
1403 i = p->state ? ffz(~p->state) + 1 : 0;
1404 psinfo->pr_state = i;
1405 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
1406 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1407 psinfo->pr_nice = task_nice(p);
1408 psinfo->pr_flag = p->flags;
David Howellsc69e8d92008-11-14 10:39:19 +11001409 rcu_read_lock();
1410 cred = __task_cred(p);
Eric W. Biedermanebc887b2012-02-07 18:36:10 -08001411 SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid));
1412 SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid));
David Howellsc69e8d92008-11-14 10:39:19 +11001413 rcu_read_unlock();
David Howells6d8c4e32006-07-10 04:44:55 -07001414 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1415
1416 return 0;
1417}
1418
1419/* Here is the structure in which status of each thread is captured. */
1420struct elf_thread_status
1421{
1422 struct list_head list;
1423 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1424 elf_fpregset_t fpu; /* NT_PRFPREG */
1425 struct task_struct *thread;
1426#ifdef ELF_CORE_COPY_XFPREGS
Mark Nelson5b20cd82007-10-16 23:25:39 -07001427 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
David Howells6d8c4e32006-07-10 04:44:55 -07001428#endif
1429 struct memelfnote notes[3];
1430 int num_notes;
1431};
1432
1433/*
1434 * In order to add the specific thread information for the elf file format,
1435 * we need to keep a linked list of every thread's pr_status and then create
1436 * a single section for them in the final core file.
1437 */
1438static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1439{
1440 struct task_struct *p = t->thread;
1441 int sz = 0;
1442
1443 t->num_notes = 0;
1444
1445 fill_prstatus(&t->prstatus, p, signr);
1446 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1447
1448 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1449 &t->prstatus);
1450 t->num_notes++;
1451 sz += notesize(&t->notes[0]);
1452
1453 t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, &t->fpu);
1454 if (t->prstatus.pr_fpvalid) {
1455 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1456 &t->fpu);
1457 t->num_notes++;
1458 sz += notesize(&t->notes[1]);
1459 }
1460
1461#ifdef ELF_CORE_COPY_XFPREGS
1462 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
Mark Nelson5b20cd82007-10-16 23:25:39 -07001463 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1464 sizeof(t->xfpu), &t->xfpu);
David Howells6d8c4e32006-07-10 04:44:55 -07001465 t->num_notes++;
1466 sz += notesize(&t->notes[2]);
1467 }
1468#endif
1469 return sz;
1470}
1471
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001472static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
1473 elf_addr_t e_shoff, int segs)
1474{
1475 elf->e_shoff = e_shoff;
1476 elf->e_shentsize = sizeof(*shdr4extnum);
1477 elf->e_shnum = 1;
1478 elf->e_shstrndx = SHN_UNDEF;
1479
1480 memset(shdr4extnum, 0, sizeof(*shdr4extnum));
1481
1482 shdr4extnum->sh_type = SHT_NULL;
1483 shdr4extnum->sh_size = elf->e_shnum;
1484 shdr4extnum->sh_link = elf->e_shstrndx;
1485 shdr4extnum->sh_info = segs;
1486}
1487
David Howells6d8c4e32006-07-10 04:44:55 -07001488/*
1489 * dump the segments for an MMU process
1490 */
Al Viroe6c1baa2013-10-05 18:58:47 -04001491static bool elf_fdpic_dump_segments(struct coredump_params *cprm)
David Howells6d8c4e32006-07-10 04:44:55 -07001492{
1493 struct vm_area_struct *vma;
1494
1495 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
1496 unsigned long addr;
1497
Al Viroe6c1baa2013-10-05 18:58:47 -04001498 if (!maydump(vma, cprm->mm_flags))
David Howells6d8c4e32006-07-10 04:44:55 -07001499 continue;
1500
Al Viroe6c1baa2013-10-05 18:58:47 -04001501#ifdef CONFIG_MMU
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07001502 for (addr = vma->vm_start; addr < vma->vm_end;
1503 addr += PAGE_SIZE) {
Al Viroe6c1baa2013-10-05 18:58:47 -04001504 bool res;
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07001505 struct page *page = get_dump_page(addr);
1506 if (page) {
1507 void *kaddr = kmap(page);
Al Viroe6c1baa2013-10-05 18:58:47 -04001508 res = dump_emit(cprm, kaddr, PAGE_SIZE);
David Howells6d8c4e32006-07-10 04:44:55 -07001509 kunmap(page);
1510 page_cache_release(page);
Al Viroe6c1baa2013-10-05 18:58:47 -04001511 } else {
1512 res = dump_seek(file, PAGE_SIZE);
1513 }
1514 if (!res)
1515 return false;
David Howells6d8c4e32006-07-10 04:44:55 -07001516 }
Al Viroe6c1baa2013-10-05 18:58:47 -04001517#else
1518 if (!dump_emit(cprm, (void *) vma->vm_start,
David Howells6d8c4e32006-07-10 04:44:55 -07001519 vma->vm_end - vma->vm_start))
Al Viroe6c1baa2013-10-05 18:58:47 -04001520 return false;
David Howells6d8c4e32006-07-10 04:44:55 -07001521#endif
Al Viroe6c1baa2013-10-05 18:58:47 -04001522 }
1523 return true;
1524}
David Howells6d8c4e32006-07-10 04:44:55 -07001525
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001526static size_t elf_core_vma_data_size(unsigned long mm_flags)
1527{
1528 struct vm_area_struct *vma;
1529 size_t size = 0;
1530
David Howells47568d42010-03-24 17:02:28 +00001531 for (vma = current->mm->mmap; vma; vma = vma->vm_next)
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001532 if (maydump(vma, mm_flags))
1533 size += vma->vm_end - vma->vm_start;
1534 return size;
1535}
1536
David Howells6d8c4e32006-07-10 04:44:55 -07001537/*
1538 * Actual dumper
1539 *
1540 * This is a two-pass process; first we find the offsets of the bits,
1541 * and then they are actually written out. If we run out of core limit
1542 * we just truncate.
1543 */
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08001544static int elf_fdpic_core_dump(struct coredump_params *cprm)
David Howells6d8c4e32006-07-10 04:44:55 -07001545{
1546#define NUM_NOTES 6
1547 int has_dumped = 0;
1548 mm_segment_t fs;
1549 int segs;
1550 size_t size = 0;
1551 int i;
1552 struct vm_area_struct *vma;
1553 struct elfhdr *elf = NULL;
Daisuke HATAYAMA05f47fd2010-03-05 13:44:05 -08001554 loff_t offset = 0, dataoff, foffset;
David Howells6d8c4e32006-07-10 04:44:55 -07001555 int numnote;
1556 struct memelfnote *notes = NULL;
1557 struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
1558 struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */
David Howells6d8c4e32006-07-10 04:44:55 -07001559 LIST_HEAD(thread_list);
1560 struct list_head *t;
1561 elf_fpregset_t *fpu = NULL;
1562#ifdef ELF_CORE_COPY_XFPREGS
1563 elf_fpxregset_t *xfpu = NULL;
1564#endif
1565 int thread_status_size = 0;
David Howells6d8c4e32006-07-10 04:44:55 -07001566 elf_addr_t *auxv;
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08001567 struct elf_phdr *phdr4note = NULL;
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001568 struct elf_shdr *shdr4extnum = NULL;
1569 Elf_Half e_phnum;
1570 elf_addr_t e_shoff;
David Howells6d8c4e32006-07-10 04:44:55 -07001571
1572 /*
1573 * We no longer stop all VM operations.
1574 *
1575 * This is because those proceses that could possibly change map_count
1576 * or the mmap / vma pages are now blocked in do_exit on current
1577 * finishing this core dump.
1578 *
1579 * Only ptrace can touch these memory addresses, but it doesn't change
1580 * the map_count or the pages allocated. So no possibility of crashing
1581 * exists while dumping the mm->vm_next areas to the core file.
1582 */
1583
1584 /* alloc memory for large data structures: too large to be on stack */
1585 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1586 if (!elf)
1587 goto cleanup;
1588 prstatus = kzalloc(sizeof(*prstatus), GFP_KERNEL);
1589 if (!prstatus)
1590 goto cleanup;
1591 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1592 if (!psinfo)
1593 goto cleanup;
1594 notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL);
1595 if (!notes)
1596 goto cleanup;
1597 fpu = kmalloc(sizeof(*fpu), GFP_KERNEL);
1598 if (!fpu)
1599 goto cleanup;
1600#ifdef ELF_CORE_COPY_XFPREGS
1601 xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL);
1602 if (!xfpu)
1603 goto cleanup;
1604#endif
1605
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001606 if (cprm->siginfo->si_signo) {
Oleg Nesterov182c5152008-07-25 01:47:45 -07001607 struct core_thread *ct;
David Howells6d8c4e32006-07-10 04:44:55 -07001608 struct elf_thread_status *tmp;
Oleg Nesterov24d52882008-07-25 01:47:40 -07001609
Oleg Nesterov182c5152008-07-25 01:47:45 -07001610 for (ct = current->mm->core_state->dumper.next;
1611 ct; ct = ct->next) {
1612 tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
1613 if (!tmp)
1614 goto cleanup;
1615
1616 tmp->thread = ct->task;
1617 list_add(&tmp->list, &thread_list);
1618 }
1619
David Howells6d8c4e32006-07-10 04:44:55 -07001620 list_for_each(t, &thread_list) {
1621 struct elf_thread_status *tmp;
1622 int sz;
1623
1624 tmp = list_entry(t, struct elf_thread_status, list);
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001625 sz = elf_dump_thread_status(cprm->siginfo->si_signo, tmp);
David Howells6d8c4e32006-07-10 04:44:55 -07001626 thread_status_size += sz;
1627 }
1628 }
1629
1630 /* now collect the dump for the current */
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001631 fill_prstatus(prstatus, current, cprm->siginfo->si_signo);
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08001632 elf_core_copy_regs(&prstatus->pr_reg, cprm->regs);
David Howells6d8c4e32006-07-10 04:44:55 -07001633
David Howells6d8c4e32006-07-10 04:44:55 -07001634 segs = current->mm->map_count;
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08001635 segs += elf_core_extra_phdrs();
David Howells6d8c4e32006-07-10 04:44:55 -07001636
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001637 /* for notes section */
1638 segs++;
1639
1640 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
1641 * this, kernel supports extended numbering. Have a look at
1642 * include/linux/elf.h for further information. */
1643 e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
1644
David Howells6d8c4e32006-07-10 04:44:55 -07001645 /* Set up header */
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001646 fill_elf_fdpic_header(elf, e_phnum);
David Howells6d8c4e32006-07-10 04:44:55 -07001647
1648 has_dumped = 1;
David Howells6d8c4e32006-07-10 04:44:55 -07001649 /*
1650 * Set up the notes in similar form to SVR4 core dumps made
1651 * with info from their /proc.
1652 */
1653
1654 fill_note(notes + 0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus);
1655 fill_psinfo(psinfo, current->group_leader, current->mm);
1656 fill_note(notes + 1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1657
1658 numnote = 2;
1659
1660 auxv = (elf_addr_t *) current->mm->saved_auxv;
1661
1662 i = 0;
1663 do
1664 i += 2;
1665 while (auxv[i - 2] != AT_NULL);
1666 fill_note(&notes[numnote++], "CORE", NT_AUXV,
1667 i * sizeof(elf_addr_t), auxv);
1668
1669 /* Try to dump the FPU. */
1670 if ((prstatus->pr_fpvalid =
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08001671 elf_core_copy_task_fpregs(current, cprm->regs, fpu)))
David Howells6d8c4e32006-07-10 04:44:55 -07001672 fill_note(notes + numnote++,
1673 "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
1674#ifdef ELF_CORE_COPY_XFPREGS
1675 if (elf_core_copy_task_xfpregs(current, xfpu))
1676 fill_note(notes + numnote++,
Mark Nelson5b20cd82007-10-16 23:25:39 -07001677 "LINUX", ELF_CORE_XFPREG_TYPE, sizeof(*xfpu), xfpu);
David Howells6d8c4e32006-07-10 04:44:55 -07001678#endif
1679
1680 fs = get_fs();
1681 set_fs(KERNEL_DS);
1682
David Howells6d8c4e32006-07-10 04:44:55 -07001683 offset += sizeof(*elf); /* Elf header */
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001684 offset += segs * sizeof(struct elf_phdr); /* Program headers */
Daisuke HATAYAMA05f47fd2010-03-05 13:44:05 -08001685 foffset = offset;
David Howells6d8c4e32006-07-10 04:44:55 -07001686
1687 /* Write notes phdr entry */
1688 {
David Howells6d8c4e32006-07-10 04:44:55 -07001689 int sz = 0;
1690
1691 for (i = 0; i < numnote; i++)
1692 sz += notesize(notes + i);
1693
1694 sz += thread_status_size;
1695
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08001696 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
1697 if (!phdr4note)
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -08001698 goto end_coredump;
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08001699
1700 fill_elf_note_phdr(phdr4note, sz, offset);
1701 offset += sz;
David Howells6d8c4e32006-07-10 04:44:55 -07001702 }
1703
1704 /* Page-align dumped data */
1705 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1706
Masami Hiramatsu30736a42010-03-05 13:44:12 -08001707 offset += elf_core_vma_data_size(cprm->mm_flags);
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001708 offset += elf_core_extra_data_size();
1709 e_shoff = offset;
1710
1711 if (e_phnum == PN_XNUM) {
1712 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
1713 if (!shdr4extnum)
1714 goto end_coredump;
1715 fill_extnum_info(elf, shdr4extnum, e_shoff, segs);
1716 }
1717
1718 offset = dataoff;
1719
Al Viroe6c1baa2013-10-05 18:58:47 -04001720 if (!dump_emit(cprm, elf, sizeof(*elf)))
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08001721 goto end_coredump;
1722
Al Viroe6c1baa2013-10-05 18:58:47 -04001723 if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note)))
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08001724 goto end_coredump;
1725
David Howells6d8c4e32006-07-10 04:44:55 -07001726 /* write program headers for segments dump */
David Howells8feae132009-01-08 12:04:47 +00001727 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
David Howells6d8c4e32006-07-10 04:44:55 -07001728 struct elf_phdr phdr;
1729 size_t sz;
1730
David Howells6d8c4e32006-07-10 04:44:55 -07001731 sz = vma->vm_end - vma->vm_start;
1732
1733 phdr.p_type = PT_LOAD;
1734 phdr.p_offset = offset;
1735 phdr.p_vaddr = vma->vm_start;
1736 phdr.p_paddr = 0;
Masami Hiramatsu30736a42010-03-05 13:44:12 -08001737 phdr.p_filesz = maydump(vma, cprm->mm_flags) ? sz : 0;
David Howells6d8c4e32006-07-10 04:44:55 -07001738 phdr.p_memsz = sz;
1739 offset += phdr.p_filesz;
1740 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
1741 if (vma->vm_flags & VM_WRITE)
1742 phdr.p_flags |= PF_W;
1743 if (vma->vm_flags & VM_EXEC)
1744 phdr.p_flags |= PF_X;
1745 phdr.p_align = ELF_EXEC_PAGESIZE;
1746
Al Viroe6c1baa2013-10-05 18:58:47 -04001747 if (!dump_emit(cprm, &phdr, sizeof(phdr)))
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -08001748 goto end_coredump;
David Howells6d8c4e32006-07-10 04:44:55 -07001749 }
1750
Al Viro506f21c2013-10-05 17:22:57 -04001751 if (!elf_core_write_extra_phdrs(cprm, offset))
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08001752 goto end_coredump;
David Howells6d8c4e32006-07-10 04:44:55 -07001753
Al Viro506f21c2013-10-05 17:22:57 -04001754 size = cprm->written;
Al Viroe6c1baa2013-10-05 18:58:47 -04001755 cprm->written = foffset;
David Howells6d8c4e32006-07-10 04:44:55 -07001756 /* write out the notes section */
1757 for (i = 0; i < numnote; i++)
Al Viroe6c1baa2013-10-05 18:58:47 -04001758 if (!writenote(notes + i, cprm))
David Howells6d8c4e32006-07-10 04:44:55 -07001759 goto end_coredump;
1760
1761 /* write out the thread status notes section */
1762 list_for_each(t, &thread_list) {
1763 struct elf_thread_status *tmp =
1764 list_entry(t, struct elf_thread_status, list);
1765
1766 for (i = 0; i < tmp->num_notes; i++)
Al Viroe6c1baa2013-10-05 18:58:47 -04001767 if (!writenote(&tmp->notes[i], cprm))
David Howells6d8c4e32006-07-10 04:44:55 -07001768 goto end_coredump;
1769 }
1770
Al Viroe6c1baa2013-10-05 18:58:47 -04001771 if (!dump_seek(cprm->file, dataoff - cprm->written))
David Howells6d8c4e32006-07-10 04:44:55 -07001772 goto end_coredump;
1773
Al Viroaa3e7ea2013-10-05 17:50:15 -04001774 cprm->written = size;
Al Viroe6c1baa2013-10-05 18:58:47 -04001775 if (!elf_fdpic_dump_segments(cprm))
1776 goto end_coredump;
1777
Al Viroaa3e7ea2013-10-05 17:50:15 -04001778 if (!elf_core_write_extra_data(cprm))
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08001779 goto end_coredump;
David Howells6d8c4e32006-07-10 04:44:55 -07001780
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001781 if (e_phnum == PN_XNUM) {
Al Viroe6c1baa2013-10-05 18:58:47 -04001782 if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum)))
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001783 goto end_coredump;
1784 }
1785
Daisuke HATAYAMA2f489122010-01-04 15:42:14 +09001786 if (cprm->file->f_pos != offset) {
David Howells6d8c4e32006-07-10 04:44:55 -07001787 /* Sanity check */
1788 printk(KERN_WARNING
1789 "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n",
Daisuke HATAYAMA2f489122010-01-04 15:42:14 +09001790 cprm->file->f_pos, offset);
David Howells6d8c4e32006-07-10 04:44:55 -07001791 }
1792
1793end_coredump:
1794 set_fs(fs);
1795
1796cleanup:
1797 while (!list_empty(&thread_list)) {
1798 struct list_head *tmp = thread_list.next;
1799 list_del(tmp);
1800 kfree(list_entry(tmp, struct elf_thread_status, list));
1801 }
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08001802 kfree(phdr4note);
David Howells6d8c4e32006-07-10 04:44:55 -07001803 kfree(elf);
1804 kfree(prstatus);
1805 kfree(psinfo);
1806 kfree(notes);
1807 kfree(fpu);
Davidlohr Buesobcb65a72011-07-06 12:26:05 +01001808 kfree(shdr4extnum);
David Howells6d8c4e32006-07-10 04:44:55 -07001809#ifdef ELF_CORE_COPY_XFPREGS
1810 kfree(xfpu);
1811#endif
1812 return has_dumped;
1813#undef NUM_NOTES
1814}
1815
Christoph Hellwig698ba7b2009-12-15 16:47:37 -08001816#endif /* CONFIG_ELF_CORE */