1 /* binfmt_elf_fdpic.c: FDPIC ELF binary format
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
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.
13 #include <linux/module.h>
16 #include <linux/stat.h>
17 #include <linux/sched.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 #include <linux/coredump.h>
39 #include <asm/uaccess.h>
40 #include <asm/param.h>
41 #include <asm/pgalloc.h>
43 typedef char *elf_caddr_t;
46 #define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
48 #define kdebug(fmt, ...) do {} while(0)
52 #define kdcore(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
54 #define kdcore(fmt, ...) do {} while(0)
57 MODULE_LICENSE("GPL");
59 static int load_elf_fdpic_binary(struct linux_binprm *, struct pt_regs *);
60 static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *, struct file *);
61 static int elf_fdpic_map_file(struct elf_fdpic_params *, struct file *,
62 struct mm_struct *, const char *);
64 static int create_elf_fdpic_tables(struct linux_binprm *, struct mm_struct *,
65 struct elf_fdpic_params *,
66 struct elf_fdpic_params *);
69 static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *,
71 static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *,
76 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *,
77 struct file *, struct mm_struct *);
79 #ifdef CONFIG_ELF_CORE
80 static int elf_fdpic_core_dump(struct coredump_params *cprm);
83 static struct linux_binfmt elf_fdpic_format = {
84 .module = THIS_MODULE,
85 .load_binary = load_elf_fdpic_binary,
86 #ifdef CONFIG_ELF_CORE
87 .core_dump = elf_fdpic_core_dump,
89 .min_coredump = ELF_EXEC_PAGESIZE,
92 static int __init init_elf_fdpic_binfmt(void)
94 return register_binfmt(&elf_fdpic_format);
97 static void __exit exit_elf_fdpic_binfmt(void)
99 unregister_binfmt(&elf_fdpic_format);
102 core_initcall(init_elf_fdpic_binfmt);
103 module_exit(exit_elf_fdpic_binfmt);
105 static int is_elf_fdpic(struct elfhdr *hdr, struct file *file)
107 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0)
109 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)
111 if (!elf_check_arch(hdr) || !elf_check_fdpic(hdr))
113 if (!file->f_op || !file->f_op->mmap)
118 /*****************************************************************************/
120 * read the program headers table into memory
122 static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params,
125 struct elf32_phdr *phdr;
129 if (params->hdr.e_phentsize != sizeof(struct elf_phdr))
131 if (params->hdr.e_phnum > 65536U / sizeof(struct elf_phdr))
134 size = params->hdr.e_phnum * sizeof(struct elf_phdr);
135 params->phdrs = kmalloc(size, GFP_KERNEL);
139 retval = kernel_read(file, params->hdr.e_phoff,
140 (char *) params->phdrs, size);
141 if (unlikely(retval != size))
142 return retval < 0 ? retval : -ENOEXEC;
144 /* determine stack size for this binary */
145 phdr = params->phdrs;
146 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
147 if (phdr->p_type != PT_GNU_STACK)
150 if (phdr->p_flags & PF_X)
151 params->flags |= ELF_FDPIC_FLAG_EXEC_STACK;
153 params->flags |= ELF_FDPIC_FLAG_NOEXEC_STACK;
155 params->stack_size = phdr->p_memsz;
162 /*****************************************************************************/
164 * load an fdpic binary into various bits of memory
166 static int load_elf_fdpic_binary(struct linux_binprm *bprm,
167 struct pt_regs *regs)
169 struct elf_fdpic_params exec_params, interp_params;
170 struct elf_phdr *phdr;
171 unsigned long stack_size, entryaddr;
172 #ifdef ELF_FDPIC_PLAT_INIT
173 unsigned long dynaddr;
176 unsigned long stack_prot;
178 struct file *interpreter = NULL; /* to shut gcc up */
179 char *interpreter_name = NULL;
180 int executable_stack;
183 kdebug("____ LOAD %d ____", current->pid);
185 memset(&exec_params, 0, sizeof(exec_params));
186 memset(&interp_params, 0, sizeof(interp_params));
188 exec_params.hdr = *(struct elfhdr *) bprm->buf;
189 exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE;
191 /* check that this is a binary we know how to deal with */
193 if (!is_elf_fdpic(&exec_params.hdr, bprm->file))
196 /* read the program header table */
197 retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);
201 /* scan for a program header that specifies an interpreter */
202 phdr = exec_params.phdrs;
204 for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) {
205 switch (phdr->p_type) {
208 if (phdr->p_filesz > PATH_MAX)
211 if (phdr->p_filesz < 2)
214 /* read the name of the interpreter into memory */
215 interpreter_name = kmalloc(phdr->p_filesz, GFP_KERNEL);
216 if (!interpreter_name)
219 retval = kernel_read(bprm->file,
223 if (unlikely(retval != phdr->p_filesz)) {
230 if (interpreter_name[phdr->p_filesz - 1] != '\0')
233 kdebug("Using ELF interpreter %s", interpreter_name);
235 /* replace the program with the interpreter */
236 interpreter = open_exec(interpreter_name);
237 retval = PTR_ERR(interpreter);
238 if (IS_ERR(interpreter)) {
244 * If the binary is not readable then enforce
245 * mm->dumpable = 0 regardless of the interpreter's
248 if (file_permission(interpreter, MAY_READ) < 0)
249 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
251 retval = kernel_read(interpreter, 0, bprm->buf,
253 if (unlikely(retval != BINPRM_BUF_SIZE)) {
259 interp_params.hdr = *((struct elfhdr *) bprm->buf);
264 if (exec_params.load_addr == 0)
265 exec_params.load_addr = phdr->p_vaddr;
272 if (elf_check_const_displacement(&exec_params.hdr))
273 exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
275 /* perform insanity checks on the interpreter */
276 if (interpreter_name) {
278 if (!is_elf_fdpic(&interp_params.hdr, interpreter))
281 interp_params.flags = ELF_FDPIC_FLAG_PRESENT;
283 /* read the interpreter's program header table */
284 retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter);
289 stack_size = exec_params.stack_size;
290 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;
295 executable_stack = EXSTACK_DEFAULT;
297 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;
304 executable_stack = EXSTACK_DEFAULT;
311 if (elf_check_const_displacement(&interp_params.hdr))
312 interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
314 /* flush all traces of the currently running executable */
315 retval = flush_old_exec(bprm);
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
322 set_personality(PER_LINUX_FDPIC);
323 if (elf_read_implies_exec(&exec_params.hdr, executable_stack))
324 current->personality |= READ_IMPLIES_EXEC;
326 setup_new_exec(bprm);
328 set_binfmt(&elf_fdpic_format);
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;
338 current->flags &= ~PF_FORKNOEXEC;
341 elf_fdpic_arch_lay_out_mm(&exec_params,
343 ¤t->mm->start_stack,
344 ¤t->mm->start_brk);
346 retval = setup_arg_pages(bprm, current->mm->start_stack,
349 send_sig(SIGKILL, current, 0);
354 /* load the executable and interpreter into memory */
355 retval = elf_fdpic_map_file(&exec_params, bprm->file, current->mm,
360 if (interpreter_name) {
361 retval = elf_fdpic_map_file(&interp_params, interpreter,
362 current->mm, "interpreter");
364 printk(KERN_ERR "Unable to load interpreter\n");
368 allow_write_access(interpreter);
374 if (!current->mm->start_brk)
375 current->mm->start_brk = current->mm->end_data;
377 current->mm->brk = current->mm->start_brk =
378 PAGE_ALIGN(current->mm->start_brk);
381 /* create a stack and brk area big enough for everyone
382 * - the brk heap starts at the bottom and works up
383 * - the stack starts at the top and works down
385 stack_size = (stack_size + PAGE_SIZE - 1) & PAGE_MASK;
386 if (stack_size < PAGE_SIZE * 2)
387 stack_size = PAGE_SIZE * 2;
389 stack_prot = PROT_READ | PROT_WRITE;
390 if (executable_stack == EXSTACK_ENABLE_X ||
391 (executable_stack == EXSTACK_DEFAULT && VM_STACK_FLAGS & VM_EXEC))
392 stack_prot |= PROT_EXEC;
394 down_write(¤t->mm->mmap_sem);
395 current->mm->start_brk = do_mmap(NULL, 0, stack_size, stack_prot,
396 MAP_PRIVATE | MAP_ANONYMOUS |
397 MAP_UNINITIALIZED | MAP_GROWSDOWN,
400 if (IS_ERR_VALUE(current->mm->start_brk)) {
401 up_write(¤t->mm->mmap_sem);
402 retval = current->mm->start_brk;
403 current->mm->start_brk = 0;
407 up_write(¤t->mm->mmap_sem);
409 current->mm->brk = current->mm->start_brk;
410 current->mm->context.end_brk = current->mm->start_brk;
411 current->mm->context.end_brk +=
412 (stack_size > PAGE_SIZE) ? (stack_size - PAGE_SIZE) : 0;
413 current->mm->start_stack = current->mm->start_brk + stack_size;
416 install_exec_creds(bprm);
417 current->flags &= ~PF_FORKNOEXEC;
418 if (create_elf_fdpic_tables(bprm, current->mm,
419 &exec_params, &interp_params) < 0)
422 kdebug("- start_code %lx", current->mm->start_code);
423 kdebug("- end_code %lx", current->mm->end_code);
424 kdebug("- start_data %lx", current->mm->start_data);
425 kdebug("- end_data %lx", current->mm->end_data);
426 kdebug("- start_brk %lx", current->mm->start_brk);
427 kdebug("- brk %lx", current->mm->brk);
428 kdebug("- start_stack %lx", current->mm->start_stack);
430 #ifdef ELF_FDPIC_PLAT_INIT
432 * The ABI may specify that certain registers be set up in special
433 * ways (on i386 %edx is the address of a DT_FINI function, for
434 * example. This macro performs whatever initialization to
435 * the regs structure is required.
437 dynaddr = interp_params.dynamic_addr ?: exec_params.dynamic_addr;
438 ELF_FDPIC_PLAT_INIT(regs, exec_params.map_addr, interp_params.map_addr,
442 /* everything is now ready... get the userspace context ready to roll */
443 entryaddr = interp_params.entry_addr ?: exec_params.entry_addr;
444 start_thread(regs, entryaddr, current->mm->start_stack);
450 allow_write_access(interpreter);
453 kfree(interpreter_name);
454 kfree(exec_params.phdrs);
455 kfree(exec_params.loadmap);
456 kfree(interp_params.phdrs);
457 kfree(interp_params.loadmap);
460 /* unrecoverable error - kill the process */
462 send_sig(SIGSEGV, current, 0);
467 /*****************************************************************************/
469 #ifndef ELF_BASE_PLATFORM
471 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
472 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
473 * will be copied to the user stack in the same manner as AT_PLATFORM.
475 #define ELF_BASE_PLATFORM NULL
479 * present useful information to the program by shovelling it onto the new
482 static int create_elf_fdpic_tables(struct linux_binprm *bprm,
483 struct mm_struct *mm,
484 struct elf_fdpic_params *exec_params,
485 struct elf_fdpic_params *interp_params)
487 const struct cred *cred = current_cred();
488 unsigned long sp, csp, nitems;
489 elf_caddr_t __user *argv, *envp;
490 size_t platform_len = 0, len;
491 char *k_platform, *k_base_platform;
492 char __user *u_platform, *u_base_platform, *p;
495 int nr; /* reset for each csp adjustment */
498 /* In some cases (e.g. Hyper-Threading), we want to avoid L1 evictions
499 * by the processes running on the same package. One thing we can do is
500 * to shuffle the initial stack for them, so we give the architecture
501 * an opportunity to do so here.
503 sp = arch_align_stack(bprm->p);
505 sp = mm->start_stack;
507 /* stack the program arguments and environment */
508 if (elf_fdpic_transfer_args_to_stack(bprm, &sp) < 0)
515 * If this architecture has a platform capability string, copy it
516 * to userspace. In some cases (Sparc), this info is impossible
517 * for userspace to get any other way, in others (i386) it is
520 k_platform = ELF_PLATFORM;
524 platform_len = strlen(k_platform) + 1;
526 u_platform = (char __user *) sp;
527 if (__copy_to_user(u_platform, k_platform, platform_len) != 0)
532 * If this architecture has a "base" platform capability
533 * string, copy it to userspace.
535 k_base_platform = ELF_BASE_PLATFORM;
536 u_base_platform = NULL;
538 if (k_base_platform) {
539 platform_len = strlen(k_base_platform) + 1;
541 u_base_platform = (char __user *) sp;
542 if (__copy_to_user(u_base_platform, k_base_platform, platform_len) != 0)
548 /* stack the load map(s) */
549 len = sizeof(struct elf32_fdpic_loadmap);
550 len += sizeof(struct elf32_fdpic_loadseg) * exec_params->loadmap->nsegs;
551 sp = (sp - len) & ~7UL;
552 exec_params->map_addr = sp;
554 if (copy_to_user((void __user *) sp, exec_params->loadmap, len) != 0)
557 current->mm->context.exec_fdpic_loadmap = (unsigned long) sp;
559 if (interp_params->loadmap) {
560 len = sizeof(struct elf32_fdpic_loadmap);
561 len += sizeof(struct elf32_fdpic_loadseg) *
562 interp_params->loadmap->nsegs;
563 sp = (sp - len) & ~7UL;
564 interp_params->map_addr = sp;
566 if (copy_to_user((void __user *) sp, interp_params->loadmap,
570 current->mm->context.interp_fdpic_loadmap = (unsigned long) sp;
573 /* force 16 byte _final_ alignment here for generality */
574 #define DLINFO_ITEMS 15
576 nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) +
577 (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH;
579 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD)
583 sp -= nitems * 2 * sizeof(unsigned long);
584 sp -= (bprm->envc + 1) * sizeof(char *); /* envv[] */
585 sp -= (bprm->argc + 1) * sizeof(char *); /* argv[] */
586 sp -= 1 * sizeof(unsigned long); /* argc */
591 /* put the ELF interpreter info on the stack */
592 #define NEW_AUX_ENT(id, val) \
594 struct { unsigned long _id, _val; } __user *ent; \
596 ent = (void __user *) csp; \
597 __put_user((id), &ent[nr]._id); \
598 __put_user((val), &ent[nr]._val); \
603 csp -= 2 * sizeof(unsigned long);
604 NEW_AUX_ENT(AT_NULL, 0);
607 csp -= 2 * sizeof(unsigned long);
608 NEW_AUX_ENT(AT_PLATFORM,
609 (elf_addr_t) (unsigned long) u_platform);
612 if (k_base_platform) {
614 csp -= 2 * sizeof(unsigned long);
615 NEW_AUX_ENT(AT_BASE_PLATFORM,
616 (elf_addr_t) (unsigned long) u_base_platform);
619 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
621 csp -= 2 * sizeof(unsigned long);
622 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
626 csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long);
627 NEW_AUX_ENT(AT_HWCAP, hwcap);
628 NEW_AUX_ENT(AT_PAGESZ, PAGE_SIZE);
629 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
630 NEW_AUX_ENT(AT_PHDR, exec_params->ph_addr);
631 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
632 NEW_AUX_ENT(AT_PHNUM, exec_params->hdr.e_phnum);
633 NEW_AUX_ENT(AT_BASE, interp_params->elfhdr_addr);
634 NEW_AUX_ENT(AT_FLAGS, 0);
635 NEW_AUX_ENT(AT_ENTRY, exec_params->entry_addr);
636 NEW_AUX_ENT(AT_UID, (elf_addr_t) cred->uid);
637 NEW_AUX_ENT(AT_EUID, (elf_addr_t) cred->euid);
638 NEW_AUX_ENT(AT_GID, (elf_addr_t) cred->gid);
639 NEW_AUX_ENT(AT_EGID, (elf_addr_t) cred->egid);
640 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
641 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
645 csp -= AT_VECTOR_SIZE_ARCH * 2 * sizeof(unsigned long);
647 /* ARCH_DLINFO must come last so platform specific code can enforce
648 * special alignment requirements on the AUXV if necessary (eg. PPC).
654 /* allocate room for argv[] and envv[] */
655 csp -= (bprm->envc + 1) * sizeof(elf_caddr_t);
656 envp = (elf_caddr_t __user *) csp;
657 csp -= (bprm->argc + 1) * sizeof(elf_caddr_t);
658 argv = (elf_caddr_t __user *) csp;
661 csp -= sizeof(unsigned long);
662 __put_user(bprm->argc, (unsigned long __user *) csp);
666 /* fill in the argv[] array */
668 current->mm->arg_start = bprm->p;
670 current->mm->arg_start = current->mm->start_stack -
671 (MAX_ARG_PAGES * PAGE_SIZE - bprm->p);
674 p = (char __user *) current->mm->arg_start;
675 for (loop = bprm->argc; loop > 0; loop--) {
676 __put_user((elf_caddr_t) p, argv++);
677 len = strnlen_user(p, MAX_ARG_STRLEN);
678 if (!len || len > MAX_ARG_STRLEN)
682 __put_user(NULL, argv);
683 current->mm->arg_end = (unsigned long) p;
685 /* fill in the envv[] array */
686 current->mm->env_start = (unsigned long) p;
687 for (loop = bprm->envc; loop > 0; loop--) {
688 __put_user((elf_caddr_t)(unsigned long) p, envp++);
689 len = strnlen_user(p, MAX_ARG_STRLEN);
690 if (!len || len > MAX_ARG_STRLEN)
694 __put_user(NULL, envp);
695 current->mm->env_end = (unsigned long) p;
697 mm->start_stack = (unsigned long) sp;
701 /*****************************************************************************/
703 * transfer the program arguments and environment from the holding pages onto
707 static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *bprm,
710 unsigned long index, stop, sp;
714 stop = bprm->p >> PAGE_SHIFT;
717 for (index = MAX_ARG_PAGES - 1; index >= stop; index--) {
718 src = kmap(bprm->page[index]);
720 if (copy_to_user((void *) sp, src, PAGE_SIZE) != 0)
722 kunmap(bprm->page[index]);
727 *_sp = (*_sp - (MAX_ARG_PAGES * PAGE_SIZE - bprm->p)) & ~15;
734 /*****************************************************************************/
736 * load the appropriate binary image (executable or interpreter) into memory
737 * - we assume no MMU is available
738 * - if no other PIC bits are set in params->hdr->e_flags
739 * - we assume that the LOADable segments in the binary are independently relocatable
740 * - we assume R/O executable segments are shareable
742 * - we assume the loadable parts of the image to require fixed displacement
743 * - the image is not shareable
745 static int elf_fdpic_map_file(struct elf_fdpic_params *params,
747 struct mm_struct *mm,
750 struct elf32_fdpic_loadmap *loadmap;
752 struct elf32_fdpic_loadseg *mseg;
754 struct elf32_fdpic_loadseg *seg;
755 struct elf32_phdr *phdr;
756 unsigned long load_addr, stop;
757 unsigned nloads, tmp;
761 /* allocate a load map table */
763 for (loop = 0; loop < params->hdr.e_phnum; loop++)
764 if (params->phdrs[loop].p_type == PT_LOAD)
770 size = sizeof(*loadmap) + nloads * sizeof(*seg);
771 loadmap = kzalloc(size, GFP_KERNEL);
775 params->loadmap = loadmap;
777 loadmap->version = ELF32_FDPIC_LOADMAP_VERSION;
778 loadmap->nsegs = nloads;
780 load_addr = params->load_addr;
783 /* map the requested LOADs into the memory space */
784 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
785 case ELF_FDPIC_FLAG_CONSTDISP:
786 case ELF_FDPIC_FLAG_CONTIGUOUS:
788 ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm);
794 ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm);
800 /* map the entry point */
801 if (params->hdr.e_entry) {
803 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
804 if (params->hdr.e_entry >= seg->p_vaddr &&
805 params->hdr.e_entry < seg->p_vaddr + seg->p_memsz) {
807 (params->hdr.e_entry - seg->p_vaddr) +
814 /* determine where the program header table has wound up if mapped */
815 stop = params->hdr.e_phoff;
816 stop += params->hdr.e_phnum * sizeof (struct elf_phdr);
817 phdr = params->phdrs;
819 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
820 if (phdr->p_type != PT_LOAD)
823 if (phdr->p_offset > params->hdr.e_phoff ||
824 phdr->p_offset + phdr->p_filesz < stop)
828 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
829 if (phdr->p_vaddr >= seg->p_vaddr &&
830 phdr->p_vaddr + phdr->p_filesz <=
831 seg->p_vaddr + seg->p_memsz) {
833 (phdr->p_vaddr - seg->p_vaddr) +
835 params->hdr.e_phoff - phdr->p_offset;
842 /* determine where the dynamic section has wound up if there is one */
843 phdr = params->phdrs;
844 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
845 if (phdr->p_type != PT_DYNAMIC)
849 for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
850 if (phdr->p_vaddr >= seg->p_vaddr &&
851 phdr->p_vaddr + phdr->p_memsz <=
852 seg->p_vaddr + seg->p_memsz) {
853 params->dynamic_addr =
854 (phdr->p_vaddr - seg->p_vaddr) +
857 /* check the dynamic section contains at least
858 * one item, and that the last item is a NULL
860 if (phdr->p_memsz == 0 ||
861 phdr->p_memsz % sizeof(Elf32_Dyn) != 0)
864 tmp = phdr->p_memsz / sizeof(Elf32_Dyn);
866 params->dynamic_addr)[tmp - 1].d_tag != 0)
874 /* now elide adjacent segments in the load map on MMU linux
875 * - on uClinux the holes between may actually be filled with system
876 * stuff or stuff from other processes
879 nloads = loadmap->nsegs;
880 mseg = loadmap->segs;
882 for (loop = 1; loop < nloads; loop++) {
883 /* see if we have a candidate for merging */
884 if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) {
885 load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz);
886 if (load_addr == (seg->addr & PAGE_MASK)) {
889 (mseg->addr + mseg->p_memsz);
890 mseg->p_memsz += seg->addr & ~PAGE_MASK;
891 mseg->p_memsz += seg->p_memsz;
903 kdebug("Mapped Object [%s]:", what);
904 kdebug("- elfhdr : %lx", params->elfhdr_addr);
905 kdebug("- entry : %lx", params->entry_addr);
906 kdebug("- PHDR[] : %lx", params->ph_addr);
907 kdebug("- DYNAMIC[]: %lx", params->dynamic_addr);
909 for (loop = 0; loop < loadmap->nsegs; loop++, seg++)
910 kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]",
912 seg->addr, seg->addr + seg->p_memsz - 1,
913 seg->p_vaddr, seg->p_memsz);
918 printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n",
919 what, file->f_path.dentry->d_inode->i_ino);
923 /*****************************************************************************/
925 * map a file with constant displacement under uClinux
928 static int elf_fdpic_map_file_constdisp_on_uclinux(
929 struct elf_fdpic_params *params,
931 struct mm_struct *mm)
933 struct elf32_fdpic_loadseg *seg;
934 struct elf32_phdr *phdr;
935 unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags;
939 load_addr = params->load_addr;
940 seg = params->loadmap->segs;
942 /* determine the bounds of the contiguous overall allocation we must
944 phdr = params->phdrs;
945 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
946 if (params->phdrs[loop].p_type != PT_LOAD)
949 if (base > phdr->p_vaddr)
950 base = phdr->p_vaddr;
951 if (top < phdr->p_vaddr + phdr->p_memsz)
952 top = phdr->p_vaddr + phdr->p_memsz;
955 /* allocate one big anon block for everything */
956 mflags = MAP_PRIVATE;
957 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
958 mflags |= MAP_EXECUTABLE;
960 down_write(&mm->mmap_sem);
961 maddr = do_mmap(NULL, load_addr, top - base,
962 PROT_READ | PROT_WRITE | PROT_EXEC, mflags, 0);
963 up_write(&mm->mmap_sem);
964 if (IS_ERR_VALUE(maddr))
968 load_addr += PAGE_ALIGN(top - base);
970 /* and then load the file segments into it */
971 phdr = params->phdrs;
972 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
973 if (params->phdrs[loop].p_type != PT_LOAD)
976 fpos = phdr->p_offset;
978 seg->addr = maddr + (phdr->p_vaddr - base);
979 seg->p_vaddr = phdr->p_vaddr;
980 seg->p_memsz = phdr->p_memsz;
982 ret = file->f_op->read(file, (void *) seg->addr,
983 phdr->p_filesz, &fpos);
987 /* map the ELF header address if in this segment */
988 if (phdr->p_offset == 0)
989 params->elfhdr_addr = seg->addr;
991 /* clear any space allocated but not loaded */
992 if (phdr->p_filesz < phdr->p_memsz) {
993 ret = clear_user((void *) (seg->addr + phdr->p_filesz),
994 phdr->p_memsz - phdr->p_filesz);
1000 if (phdr->p_flags & PF_X) {
1001 if (!mm->start_code) {
1002 mm->start_code = seg->addr;
1003 mm->end_code = seg->addr +
1006 } else if (!mm->start_data) {
1007 mm->start_data = seg->addr;
1009 mm->end_data = seg->addr + phdr->p_memsz;
1014 if (seg->addr + phdr->p_memsz > mm->end_data)
1015 mm->end_data = seg->addr + phdr->p_memsz;
1026 /*****************************************************************************/
1028 * map a binary by direct mmap() of the individual PT_LOAD segments
1030 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
1032 struct mm_struct *mm)
1034 struct elf32_fdpic_loadseg *seg;
1035 struct elf32_phdr *phdr;
1036 unsigned long load_addr, delta_vaddr;
1037 int loop, dvset, ret;
1039 load_addr = params->load_addr;
1043 seg = params->loadmap->segs;
1045 /* deal with each load segment separately */
1046 phdr = params->phdrs;
1047 for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
1048 unsigned long maddr, disp, excess, excess1;
1049 int prot = 0, flags;
1051 if (phdr->p_type != PT_LOAD)
1054 kdebug("[LOAD] va=%lx of=%lx fs=%lx ms=%lx",
1055 (unsigned long) phdr->p_vaddr,
1056 (unsigned long) phdr->p_offset,
1057 (unsigned long) phdr->p_filesz,
1058 (unsigned long) phdr->p_memsz);
1060 /* determine the mapping parameters */
1061 if (phdr->p_flags & PF_R) prot |= PROT_READ;
1062 if (phdr->p_flags & PF_W) prot |= PROT_WRITE;
1063 if (phdr->p_flags & PF_X) prot |= PROT_EXEC;
1065 flags = MAP_PRIVATE | MAP_DENYWRITE;
1066 if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
1067 flags |= MAP_EXECUTABLE;
1071 switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
1072 case ELF_FDPIC_FLAG_INDEPENDENT:
1073 /* PT_LOADs are independently locatable */
1076 case ELF_FDPIC_FLAG_HONOURVADDR:
1077 /* the specified virtual address must be honoured */
1078 maddr = phdr->p_vaddr;
1082 case ELF_FDPIC_FLAG_CONSTDISP:
1083 /* constant displacement
1084 * - can be mapped anywhere, but must be mapped as a
1089 delta_vaddr = phdr->p_vaddr;
1092 maddr = load_addr + phdr->p_vaddr - delta_vaddr;
1097 case ELF_FDPIC_FLAG_CONTIGUOUS:
1098 /* contiguity handled later */
1107 /* create the mapping */
1108 disp = phdr->p_vaddr & ~PAGE_MASK;
1109 down_write(&mm->mmap_sem);
1110 maddr = do_mmap(file, maddr, phdr->p_memsz + disp, prot, flags,
1111 phdr->p_offset - disp);
1112 up_write(&mm->mmap_sem);
1114 kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx",
1115 loop, phdr->p_memsz + disp, prot, flags,
1116 phdr->p_offset - disp, maddr);
1118 if (IS_ERR_VALUE(maddr))
1121 if ((params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) ==
1122 ELF_FDPIC_FLAG_CONTIGUOUS)
1123 load_addr += PAGE_ALIGN(phdr->p_memsz + disp);
1125 seg->addr = maddr + disp;
1126 seg->p_vaddr = phdr->p_vaddr;
1127 seg->p_memsz = phdr->p_memsz;
1129 /* map the ELF header address if in this segment */
1130 if (phdr->p_offset == 0)
1131 params->elfhdr_addr = seg->addr;
1133 /* clear the bit between beginning of mapping and beginning of
1135 if (prot & PROT_WRITE && disp > 0) {
1136 kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp);
1137 ret = clear_user((void __user *) maddr, disp);
1143 /* clear any space allocated but not loaded
1144 * - on uClinux we can just clear the lot
1145 * - on MMU linux we'll get a SIGBUS beyond the last page
1146 * extant in the file
1148 excess = phdr->p_memsz - phdr->p_filesz;
1149 excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
1152 if (excess > excess1) {
1153 unsigned long xaddr = maddr + phdr->p_filesz + excess1;
1154 unsigned long xmaddr;
1156 flags |= MAP_FIXED | MAP_ANONYMOUS;
1157 down_write(&mm->mmap_sem);
1158 xmaddr = do_mmap(NULL, xaddr, excess - excess1,
1160 up_write(&mm->mmap_sem);
1162 kdebug("mmap[%d] <anon>"
1163 " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",
1164 loop, xaddr, excess - excess1, prot, flags,
1167 if (xmaddr != xaddr)
1171 if (prot & PROT_WRITE && excess1 > 0) {
1172 kdebug("clear[%d] ad=%lx sz=%lx",
1173 loop, maddr + phdr->p_filesz, excess1);
1174 ret = clear_user((void __user *) maddr + phdr->p_filesz,
1182 kdebug("clear[%d] ad=%lx sz=%lx",
1183 loop, maddr + phdr->p_filesz, excess);
1184 ret = clear_user((void *) maddr + phdr->p_filesz, excess);
1191 if (phdr->p_flags & PF_X) {
1192 if (!mm->start_code) {
1193 mm->start_code = maddr;
1194 mm->end_code = maddr + phdr->p_memsz;
1196 } else if (!mm->start_data) {
1197 mm->start_data = maddr;
1198 mm->end_data = maddr + phdr->p_memsz;
1208 /*****************************************************************************/
1210 * ELF-FDPIC core dumper
1212 * Modelled on fs/exec.c:aout_core_dump()
1213 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1215 * Modelled on fs/binfmt_elf.c core dumper
1217 #ifdef CONFIG_ELF_CORE
1220 * Decide whether a segment is worth dumping; default is yes to be
1221 * sure (missing info is worse than too much; etc).
1222 * Personally I'd include everything, and use the coredump limit...
1224 * I think we should skip something. But I am not sure how. H.J.
1226 static int maydump(struct vm_area_struct *vma, unsigned long mm_flags)
1230 /* Do not dump I/O mapped devices or special mappings */
1231 if (vma->vm_flags & (VM_IO | VM_RESERVED)) {
1232 kdcore("%08lx: %08lx: no (IO)", vma->vm_start, vma->vm_flags);
1236 /* If we may not read the contents, don't allow us to dump
1237 * them either. "dump_write()" can't handle it anyway.
1239 if (!(vma->vm_flags & VM_READ)) {
1240 kdcore("%08lx: %08lx: no (!read)", vma->vm_start, vma->vm_flags);
1244 /* By default, dump shared memory if mapped from an anonymous file. */
1245 if (vma->vm_flags & VM_SHARED) {
1246 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0) {
1247 dump_ok = test_bit(MMF_DUMP_ANON_SHARED, &mm_flags);
1248 kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
1249 vma->vm_flags, dump_ok ? "yes" : "no");
1253 dump_ok = test_bit(MMF_DUMP_MAPPED_SHARED, &mm_flags);
1254 kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
1255 vma->vm_flags, dump_ok ? "yes" : "no");
1260 /* By default, if it hasn't been written to, don't write it out */
1261 if (!vma->anon_vma) {
1262 dump_ok = test_bit(MMF_DUMP_MAPPED_PRIVATE, &mm_flags);
1263 kdcore("%08lx: %08lx: %s (!anon)", vma->vm_start,
1264 vma->vm_flags, dump_ok ? "yes" : "no");
1269 dump_ok = test_bit(MMF_DUMP_ANON_PRIVATE, &mm_flags);
1270 kdcore("%08lx: %08lx: %s", vma->vm_start, vma->vm_flags,
1271 dump_ok ? "yes" : "no");
1275 /* An ELF note in memory */
1280 unsigned int datasz;
1284 static int notesize(struct memelfnote *en)
1288 sz = sizeof(struct elf_note);
1289 sz += roundup(strlen(en->name) + 1, 4);
1290 sz += roundup(en->datasz, 4);
1297 #define DUMP_WRITE(addr, nr, foffset) \
1298 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
1300 static int alignfile(struct file *file, loff_t *foffset)
1302 static const char buf[4] = { 0, };
1303 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1307 static int writenote(struct memelfnote *men, struct file *file,
1311 en.n_namesz = strlen(men->name) + 1;
1312 en.n_descsz = men->datasz;
1313 en.n_type = men->type;
1315 DUMP_WRITE(&en, sizeof(en), foffset);
1316 DUMP_WRITE(men->name, en.n_namesz, foffset);
1317 if (!alignfile(file, foffset))
1319 DUMP_WRITE(men->data, men->datasz, foffset);
1320 if (!alignfile(file, foffset))
1327 static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)
1329 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1330 elf->e_ident[EI_CLASS] = ELF_CLASS;
1331 elf->e_ident[EI_DATA] = ELF_DATA;
1332 elf->e_ident[EI_VERSION] = EV_CURRENT;
1333 elf->e_ident[EI_OSABI] = ELF_OSABI;
1334 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
1336 elf->e_type = ET_CORE;
1337 elf->e_machine = ELF_ARCH;
1338 elf->e_version = EV_CURRENT;
1340 elf->e_phoff = sizeof(struct elfhdr);
1342 elf->e_flags = ELF_FDPIC_CORE_EFLAGS;
1343 elf->e_ehsize = sizeof(struct elfhdr);
1344 elf->e_phentsize = sizeof(struct elf_phdr);
1345 elf->e_phnum = segs;
1346 elf->e_shentsize = 0;
1348 elf->e_shstrndx = 0;
1352 static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
1354 phdr->p_type = PT_NOTE;
1355 phdr->p_offset = offset;
1358 phdr->p_filesz = sz;
1365 static inline void fill_note(struct memelfnote *note, const char *name, int type,
1366 unsigned int sz, void *data)
1376 * fill up all the fields in prstatus from the given task struct, except
1377 * registers which need to be filled up separately.
1379 static void fill_prstatus(struct elf_prstatus *prstatus,
1380 struct task_struct *p, long signr)
1382 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1383 prstatus->pr_sigpend = p->pending.signal.sig[0];
1384 prstatus->pr_sighold = p->blocked.sig[0];
1386 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1388 prstatus->pr_pid = task_pid_vnr(p);
1389 prstatus->pr_pgrp = task_pgrp_vnr(p);
1390 prstatus->pr_sid = task_session_vnr(p);
1391 if (thread_group_leader(p)) {
1392 struct task_cputime cputime;
1395 * This is the record for the group leader. It shows the
1396 * group-wide total, not its individual thread total.
1398 thread_group_cputime(p, &cputime);
1399 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1400 cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
1402 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1403 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1405 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1406 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1408 prstatus->pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap;
1409 prstatus->pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap;
1412 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1413 struct mm_struct *mm)
1415 const struct cred *cred;
1416 unsigned int i, len;
1418 /* first copy the parameters from user space */
1419 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1421 len = mm->arg_end - mm->arg_start;
1422 if (len >= ELF_PRARGSZ)
1423 len = ELF_PRARGSZ - 1;
1424 if (copy_from_user(&psinfo->pr_psargs,
1425 (const char __user *) mm->arg_start, len))
1427 for (i = 0; i < len; i++)
1428 if (psinfo->pr_psargs[i] == 0)
1429 psinfo->pr_psargs[i] = ' ';
1430 psinfo->pr_psargs[len] = 0;
1433 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1435 psinfo->pr_pid = task_pid_vnr(p);
1436 psinfo->pr_pgrp = task_pgrp_vnr(p);
1437 psinfo->pr_sid = task_session_vnr(p);
1439 i = p->state ? ffz(~p->state) + 1 : 0;
1440 psinfo->pr_state = i;
1441 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
1442 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1443 psinfo->pr_nice = task_nice(p);
1444 psinfo->pr_flag = p->flags;
1446 cred = __task_cred(p);
1447 SET_UID(psinfo->pr_uid, cred->uid);
1448 SET_GID(psinfo->pr_gid, cred->gid);
1450 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1455 /* Here is the structure in which status of each thread is captured. */
1456 struct elf_thread_status
1458 struct list_head list;
1459 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1460 elf_fpregset_t fpu; /* NT_PRFPREG */
1461 struct task_struct *thread;
1462 #ifdef ELF_CORE_COPY_XFPREGS
1463 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
1465 struct memelfnote notes[3];
1470 * In order to add the specific thread information for the elf file format,
1471 * we need to keep a linked list of every thread's pr_status and then create
1472 * a single section for them in the final core file.
1474 static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1476 struct task_struct *p = t->thread;
1481 fill_prstatus(&t->prstatus, p, signr);
1482 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1484 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1487 sz += notesize(&t->notes[0]);
1489 t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, &t->fpu);
1490 if (t->prstatus.pr_fpvalid) {
1491 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1494 sz += notesize(&t->notes[1]);
1497 #ifdef ELF_CORE_COPY_XFPREGS
1498 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
1499 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1500 sizeof(t->xfpu), &t->xfpu);
1502 sz += notesize(&t->notes[2]);
1508 static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
1509 elf_addr_t e_shoff, int segs)
1511 elf->e_shoff = e_shoff;
1512 elf->e_shentsize = sizeof(*shdr4extnum);
1514 elf->e_shstrndx = SHN_UNDEF;
1516 memset(shdr4extnum, 0, sizeof(*shdr4extnum));
1518 shdr4extnum->sh_type = SHT_NULL;
1519 shdr4extnum->sh_size = elf->e_shnum;
1520 shdr4extnum->sh_link = elf->e_shstrndx;
1521 shdr4extnum->sh_info = segs;
1525 * dump the segments for an MMU process
1528 static int elf_fdpic_dump_segments(struct file *file, size_t *size,
1529 unsigned long *limit, unsigned long mm_flags)
1531 struct vm_area_struct *vma;
1534 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
1537 if (!maydump(vma, mm_flags))
1540 for (addr = vma->vm_start; addr < vma->vm_end;
1541 addr += PAGE_SIZE) {
1542 struct page *page = get_dump_page(addr);
1544 void *kaddr = kmap(page);
1548 else if (!dump_write(file, kaddr, PAGE_SIZE))
1551 page_cache_release(page);
1552 } else if (!dump_seek(file, PAGE_SIZE))
1564 * dump the segments for a NOMMU process
1567 static int elf_fdpic_dump_segments(struct file *file, size_t *size,
1568 unsigned long *limit, unsigned long mm_flags)
1570 struct vm_area_struct *vma;
1572 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
1573 if (!maydump(vma, mm_flags))
1576 if ((*size += PAGE_SIZE) > *limit)
1579 if (!dump_write(file, (void *) vma->vm_start,
1580 vma->vm_end - vma->vm_start))
1588 static size_t elf_core_vma_data_size(unsigned long mm_flags)
1590 struct vm_area_struct *vma;
1593 for (vma = current->mm->mmap; vma; vma = vma->vm_next)
1594 if (maydump(vma, mm_flags))
1595 size += vma->vm_end - vma->vm_start;
1602 * This is a two-pass process; first we find the offsets of the bits,
1603 * and then they are actually written out. If we run out of core limit
1606 static int elf_fdpic_core_dump(struct coredump_params *cprm)
1614 struct vm_area_struct *vma;
1615 struct elfhdr *elf = NULL;
1616 loff_t offset = 0, dataoff, foffset;
1618 struct memelfnote *notes = NULL;
1619 struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
1620 struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */
1621 LIST_HEAD(thread_list);
1622 struct list_head *t;
1623 elf_fpregset_t *fpu = NULL;
1624 #ifdef ELF_CORE_COPY_XFPREGS
1625 elf_fpxregset_t *xfpu = NULL;
1627 int thread_status_size = 0;
1629 struct elf_phdr *phdr4note = NULL;
1630 struct elf_shdr *shdr4extnum = NULL;
1635 * We no longer stop all VM operations.
1637 * This is because those proceses that could possibly change map_count
1638 * or the mmap / vma pages are now blocked in do_exit on current
1639 * finishing this core dump.
1641 * Only ptrace can touch these memory addresses, but it doesn't change
1642 * the map_count or the pages allocated. So no possibility of crashing
1643 * exists while dumping the mm->vm_next areas to the core file.
1646 /* alloc memory for large data structures: too large to be on stack */
1647 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1650 prstatus = kzalloc(sizeof(*prstatus), GFP_KERNEL);
1653 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1656 notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL);
1659 fpu = kmalloc(sizeof(*fpu), GFP_KERNEL);
1662 #ifdef ELF_CORE_COPY_XFPREGS
1663 xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL);
1669 struct core_thread *ct;
1670 struct elf_thread_status *tmp;
1672 for (ct = current->mm->core_state->dumper.next;
1673 ct; ct = ct->next) {
1674 tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
1678 tmp->thread = ct->task;
1679 list_add(&tmp->list, &thread_list);
1682 list_for_each(t, &thread_list) {
1683 struct elf_thread_status *tmp;
1686 tmp = list_entry(t, struct elf_thread_status, list);
1687 sz = elf_dump_thread_status(cprm->signr, tmp);
1688 thread_status_size += sz;
1692 /* now collect the dump for the current */
1693 fill_prstatus(prstatus, current, cprm->signr);
1694 elf_core_copy_regs(&prstatus->pr_reg, cprm->regs);
1696 segs = current->mm->map_count;
1697 segs += elf_core_extra_phdrs();
1699 /* for notes section */
1702 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
1703 * this, kernel supports extended numbering. Have a look at
1704 * include/linux/elf.h for further information. */
1705 e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
1708 fill_elf_fdpic_header(elf, e_phnum);
1711 current->flags |= PF_DUMPCORE;
1714 * Set up the notes in similar form to SVR4 core dumps made
1715 * with info from their /proc.
1718 fill_note(notes + 0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus);
1719 fill_psinfo(psinfo, current->group_leader, current->mm);
1720 fill_note(notes + 1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1724 auxv = (elf_addr_t *) current->mm->saved_auxv;
1729 while (auxv[i - 2] != AT_NULL);
1730 fill_note(¬es[numnote++], "CORE", NT_AUXV,
1731 i * sizeof(elf_addr_t), auxv);
1733 /* Try to dump the FPU. */
1734 if ((prstatus->pr_fpvalid =
1735 elf_core_copy_task_fpregs(current, cprm->regs, fpu)))
1736 fill_note(notes + numnote++,
1737 "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
1738 #ifdef ELF_CORE_COPY_XFPREGS
1739 if (elf_core_copy_task_xfpregs(current, xfpu))
1740 fill_note(notes + numnote++,
1741 "LINUX", ELF_CORE_XFPREG_TYPE, sizeof(*xfpu), xfpu);
1747 offset += sizeof(*elf); /* Elf header */
1748 offset += segs * sizeof(struct elf_phdr); /* Program headers */
1751 /* Write notes phdr entry */
1755 for (i = 0; i < numnote; i++)
1756 sz += notesize(notes + i);
1758 sz += thread_status_size;
1760 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
1764 fill_elf_note_phdr(phdr4note, sz, offset);
1768 /* Page-align dumped data */
1769 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1771 offset += elf_core_vma_data_size(cprm->mm_flags);
1772 offset += elf_core_extra_data_size();
1775 if (e_phnum == PN_XNUM) {
1776 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
1779 fill_extnum_info(elf, shdr4extnum, e_shoff, segs);
1784 size += sizeof(*elf);
1785 if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
1788 size += sizeof(*phdr4note);
1789 if (size > cprm->limit
1790 || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note)))
1793 /* write program headers for segments dump */
1794 for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
1795 struct elf_phdr phdr;
1798 sz = vma->vm_end - vma->vm_start;
1800 phdr.p_type = PT_LOAD;
1801 phdr.p_offset = offset;
1802 phdr.p_vaddr = vma->vm_start;
1804 phdr.p_filesz = maydump(vma, cprm->mm_flags) ? sz : 0;
1806 offset += phdr.p_filesz;
1807 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
1808 if (vma->vm_flags & VM_WRITE)
1809 phdr.p_flags |= PF_W;
1810 if (vma->vm_flags & VM_EXEC)
1811 phdr.p_flags |= PF_X;
1812 phdr.p_align = ELF_EXEC_PAGESIZE;
1814 size += sizeof(phdr);
1815 if (size > cprm->limit
1816 || !dump_write(cprm->file, &phdr, sizeof(phdr)))
1820 if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit))
1823 /* write out the notes section */
1824 for (i = 0; i < numnote; i++)
1825 if (!writenote(notes + i, cprm->file, &foffset))
1828 /* write out the thread status notes section */
1829 list_for_each(t, &thread_list) {
1830 struct elf_thread_status *tmp =
1831 list_entry(t, struct elf_thread_status, list);
1833 for (i = 0; i < tmp->num_notes; i++)
1834 if (!writenote(&tmp->notes[i], cprm->file, &foffset))
1838 if (!dump_seek(cprm->file, dataoff - foffset))
1841 if (elf_fdpic_dump_segments(cprm->file, &size, &cprm->limit,
1842 cprm->mm_flags) < 0)
1845 if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))
1848 if (e_phnum == PN_XNUM) {
1849 size += sizeof(*shdr4extnum);
1850 if (size > cprm->limit
1851 || !dump_write(cprm->file, shdr4extnum,
1852 sizeof(*shdr4extnum)))
1856 if (cprm->file->f_pos != offset) {
1859 "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n",
1860 cprm->file->f_pos, offset);
1867 while (!list_empty(&thread_list)) {
1868 struct list_head *tmp = thread_list.next;
1870 kfree(list_entry(tmp, struct elf_thread_status, list));
1878 #ifdef ELF_CORE_COPY_XFPREGS
1885 #endif /* CONFIG_ELF_CORE */