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1// SPDX-License-Identifier: GPL-2.0-or-later2/* binfmt_elf_fdpic.c: FDPIC ELF binary format3 *4 * Copyright (C) 2003, 2004, 2006 Red Hat, Inc. All Rights Reserved.5 * Written by David Howells (dhowells@redhat.com)6 * Derived from binfmt_elf.c7 */8 9#include <linux/module.h>10 11#include <linux/fs.h>12#include <linux/stat.h>13#include <linux/sched.h>14#include <linux/sched/coredump.h>15#include <linux/sched/task_stack.h>16#include <linux/sched/cputime.h>17#include <linux/mm.h>18#include <linux/mman.h>19#include <linux/errno.h>20#include <linux/signal.h>21#include <linux/binfmts.h>22#include <linux/string.h>23#include <linux/file.h>24#include <linux/fcntl.h>25#include <linux/slab.h>26#include <linux/pagemap.h>27#include <linux/security.h>28#include <linux/highmem.h>29#include <linux/highuid.h>30#include <linux/personality.h>31#include <linux/ptrace.h>32#include <linux/init.h>33#include <linux/elf.h>34#include <linux/elf-fdpic.h>35#include <linux/elfcore.h>36#include <linux/coredump.h>37#include <linux/dax.h>38#include <linux/regset.h>39 40#include <linux/uaccess.h>41#include <asm/param.h>42 43typedef char *elf_caddr_t;44 45#if 046#define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )47#else48#define kdebug(fmt, ...) do {} while(0)49#endif50 51#if 052#define kdcore(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )53#else54#define kdcore(fmt, ...) do {} while(0)55#endif56 57MODULE_LICENSE("GPL");58 59static int load_elf_fdpic_binary(struct linux_binprm *);60static 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 *);63 64static int create_elf_fdpic_tables(struct linux_binprm *, struct mm_struct *,65				   struct elf_fdpic_params *,66				   struct elf_fdpic_params *);67 68#ifndef CONFIG_MMU69static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *,70						   struct file *,71						   struct mm_struct *);72#endif73 74static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *,75					     struct file *, struct mm_struct *);76 77#ifdef CONFIG_ELF_CORE78static int elf_fdpic_core_dump(struct coredump_params *cprm);79#endif80 81static struct linux_binfmt elf_fdpic_format = {82	.module		= THIS_MODULE,83	.load_binary	= load_elf_fdpic_binary,84#ifdef CONFIG_ELF_CORE85	.core_dump	= elf_fdpic_core_dump,86	.min_coredump	= ELF_EXEC_PAGESIZE,87#endif88};89 90static int __init init_elf_fdpic_binfmt(void)91{92	register_binfmt(&elf_fdpic_format);93	return 0;94}95 96static void __exit exit_elf_fdpic_binfmt(void)97{98	unregister_binfmt(&elf_fdpic_format);99}100 101core_initcall(init_elf_fdpic_binfmt);102module_exit(exit_elf_fdpic_binfmt);103 104static int is_elf(struct elfhdr *hdr, struct file *file)105{106	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0)107		return 0;108	if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)109		return 0;110	if (!elf_check_arch(hdr))111		return 0;112	if (!file->f_op->mmap)113		return 0;114	return 1;115}116 117#ifndef elf_check_fdpic118#define elf_check_fdpic(x) 0119#endif120 121#ifndef elf_check_const_displacement122#define elf_check_const_displacement(x) 0123#endif124 125static int is_constdisp(struct elfhdr *hdr)126{127	if (!elf_check_fdpic(hdr))128		return 1;129	if (elf_check_const_displacement(hdr))130		return 1;131	return 0;132}133 134/*****************************************************************************/135/*136 * read the program headers table into memory137 */138static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params,139				 struct file *file)140{141	struct elf_phdr *phdr;142	unsigned long size;143	int retval, loop;144	loff_t pos = params->hdr.e_phoff;145 146	if (params->hdr.e_phentsize != sizeof(struct elf_phdr))147		return -ENOMEM;148	if (params->hdr.e_phnum > 65536U / sizeof(struct elf_phdr))149		return -ENOMEM;150 151	size = params->hdr.e_phnum * sizeof(struct elf_phdr);152	params->phdrs = kmalloc(size, GFP_KERNEL);153	if (!params->phdrs)154		return -ENOMEM;155 156	retval = kernel_read(file, params->phdrs, size, &pos);157	if (unlikely(retval != size))158		return retval < 0 ? retval : -ENOEXEC;159 160	/* determine stack size for this binary */161	phdr = params->phdrs;162	for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {163		if (phdr->p_type != PT_GNU_STACK)164			continue;165 166		if (phdr->p_flags & PF_X)167			params->flags |= ELF_FDPIC_FLAG_EXEC_STACK;168		else169			params->flags |= ELF_FDPIC_FLAG_NOEXEC_STACK;170 171		params->stack_size = phdr->p_memsz;172		break;173	}174 175	return 0;176}177 178/*****************************************************************************/179/*180 * load an fdpic binary into various bits of memory181 */182static int load_elf_fdpic_binary(struct linux_binprm *bprm)183{184	struct elf_fdpic_params exec_params, interp_params;185	struct pt_regs *regs = current_pt_regs();186	struct elf_phdr *phdr;187	unsigned long stack_size, entryaddr;188#ifdef ELF_FDPIC_PLAT_INIT189	unsigned long dynaddr;190#endif191#ifndef CONFIG_MMU192	unsigned long stack_prot;193#endif194	struct file *interpreter = NULL; /* to shut gcc up */195	char *interpreter_name = NULL;196	int executable_stack;197	int retval, i;198	loff_t pos;199 200	kdebug("____ LOAD %d ____", current->pid);201 202	memset(&exec_params, 0, sizeof(exec_params));203	memset(&interp_params, 0, sizeof(interp_params));204 205	exec_params.hdr = *(struct elfhdr *) bprm->buf;206	exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE;207 208	/* check that this is a binary we know how to deal with */209	retval = -ENOEXEC;210	if (!is_elf(&exec_params.hdr, bprm->file))211		goto error;212	if (!elf_check_fdpic(&exec_params.hdr)) {213#ifdef CONFIG_MMU214		/* binfmt_elf handles non-fdpic elf except on nommu */215		goto error;216#else217		/* nommu can only load ET_DYN (PIE) ELF */218		if (exec_params.hdr.e_type != ET_DYN)219			goto error;220#endif221	}222 223	/* read the program header table */224	retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);225	if (retval < 0)226		goto error;227 228	/* scan for a program header that specifies an interpreter */229	phdr = exec_params.phdrs;230 231	for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) {232		switch (phdr->p_type) {233		case PT_INTERP:234			retval = -ENOMEM;235			if (phdr->p_filesz > PATH_MAX)236				goto error;237			retval = -ENOENT;238			if (phdr->p_filesz < 2)239				goto error;240 241			/* read the name of the interpreter into memory */242			interpreter_name = kmalloc(phdr->p_filesz, GFP_KERNEL);243			if (!interpreter_name)244				goto error;245 246			pos = phdr->p_offset;247			retval = kernel_read(bprm->file, interpreter_name,248					     phdr->p_filesz, &pos);249			if (unlikely(retval != phdr->p_filesz)) {250				if (retval >= 0)251					retval = -ENOEXEC;252				goto error;253			}254 255			retval = -ENOENT;256			if (interpreter_name[phdr->p_filesz - 1] != '\0')257				goto error;258 259			kdebug("Using ELF interpreter %s", interpreter_name);260 261			/* replace the program with the interpreter */262			interpreter = open_exec(interpreter_name);263			retval = PTR_ERR(interpreter);264			if (IS_ERR(interpreter)) {265				interpreter = NULL;266				goto error;267			}268 269			/*270			 * If the binary is not readable then enforce271			 * mm->dumpable = 0 regardless of the interpreter's272			 * permissions.273			 */274			would_dump(bprm, interpreter);275 276			pos = 0;277			retval = kernel_read(interpreter, bprm->buf,278					BINPRM_BUF_SIZE, &pos);279			if (unlikely(retval != BINPRM_BUF_SIZE)) {280				if (retval >= 0)281					retval = -ENOEXEC;282				goto error;283			}284 285			interp_params.hdr = *((struct elfhdr *) bprm->buf);286			break;287 288		case PT_LOAD:289#ifdef CONFIG_MMU290			if (exec_params.load_addr == 0)291				exec_params.load_addr = phdr->p_vaddr;292#endif293			break;294		}295 296	}297 298	if (is_constdisp(&exec_params.hdr))299		exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;300 301	/* perform insanity checks on the interpreter */302	if (interpreter_name) {303		retval = -ELIBBAD;304		if (!is_elf(&interp_params.hdr, interpreter))305			goto error;306 307		interp_params.flags = ELF_FDPIC_FLAG_PRESENT;308 309		/* read the interpreter's program header table */310		retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter);311		if (retval < 0)312			goto error;313	}314 315	stack_size = exec_params.stack_size;316	if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)317		executable_stack = EXSTACK_ENABLE_X;318	else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)319		executable_stack = EXSTACK_DISABLE_X;320	else321		executable_stack = EXSTACK_DEFAULT;322 323	if (stack_size == 0 && interp_params.flags & ELF_FDPIC_FLAG_PRESENT) {324		stack_size = interp_params.stack_size;325		if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)326			executable_stack = EXSTACK_ENABLE_X;327		else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)328			executable_stack = EXSTACK_DISABLE_X;329		else330			executable_stack = EXSTACK_DEFAULT;331	}332 333	retval = -ENOEXEC;334	if (stack_size == 0)335		stack_size = 131072UL; /* same as exec.c's default commit */336 337	if (is_constdisp(&interp_params.hdr))338		interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;339 340	/* flush all traces of the currently running executable */341	retval = begin_new_exec(bprm);342	if (retval)343		goto error;344 345	/* there's now no turning back... the old userspace image is dead,346	 * defunct, deceased, etc.347	 */348	SET_PERSONALITY(exec_params.hdr);349	if (elf_check_fdpic(&exec_params.hdr))350		current->personality |= PER_LINUX_FDPIC;351	if (elf_read_implies_exec(&exec_params.hdr, executable_stack))352		current->personality |= READ_IMPLIES_EXEC;353 354	setup_new_exec(bprm);355 356	set_binfmt(&elf_fdpic_format);357 358	current->mm->start_code = 0;359	current->mm->end_code = 0;360	current->mm->start_stack = 0;361	current->mm->start_data = 0;362	current->mm->end_data = 0;363	current->mm->context.exec_fdpic_loadmap = 0;364	current->mm->context.interp_fdpic_loadmap = 0;365 366#ifdef CONFIG_MMU367	elf_fdpic_arch_lay_out_mm(&exec_params,368				  &interp_params,369				  &current->mm->start_stack,370				  &current->mm->start_brk);371 372	retval = setup_arg_pages(bprm, current->mm->start_stack,373				 executable_stack);374	if (retval < 0)375		goto error;376#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES377	retval = arch_setup_additional_pages(bprm, !!interpreter_name);378	if (retval < 0)379		goto error;380#endif381#endif382 383	/* load the executable and interpreter into memory */384	retval = elf_fdpic_map_file(&exec_params, bprm->file, current->mm,385				    "executable");386	if (retval < 0)387		goto error;388 389	if (interpreter_name) {390		retval = elf_fdpic_map_file(&interp_params, interpreter,391					    current->mm, "interpreter");392		if (retval < 0) {393			printk(KERN_ERR "Unable to load interpreter\n");394			goto error;395		}396 397		fput(interpreter);398		interpreter = NULL;399	}400 401#ifdef CONFIG_MMU402	if (!current->mm->start_brk)403		current->mm->start_brk = current->mm->end_data;404 405	current->mm->brk = current->mm->start_brk =406		PAGE_ALIGN(current->mm->start_brk);407 408#else409	/* create a stack area and zero-size brk area */410	stack_size = (stack_size + PAGE_SIZE - 1) & PAGE_MASK;411	if (stack_size < PAGE_SIZE * 2)412		stack_size = PAGE_SIZE * 2;413 414	stack_prot = PROT_READ | PROT_WRITE;415	if (executable_stack == EXSTACK_ENABLE_X ||416	    (executable_stack == EXSTACK_DEFAULT && VM_STACK_FLAGS & VM_EXEC))417		stack_prot |= PROT_EXEC;418 419	current->mm->start_brk = vm_mmap(NULL, 0, stack_size, stack_prot,420					 MAP_PRIVATE | MAP_ANONYMOUS |421					 MAP_UNINITIALIZED | MAP_GROWSDOWN,422					 0);423 424	if (IS_ERR_VALUE(current->mm->start_brk)) {425		retval = current->mm->start_brk;426		current->mm->start_brk = 0;427		goto error;428	}429 430	current->mm->brk = current->mm->start_brk;431	current->mm->context.end_brk = current->mm->start_brk;432	current->mm->start_stack = current->mm->start_brk + stack_size;433#endif434 435	retval = create_elf_fdpic_tables(bprm, current->mm, &exec_params,436					 &interp_params);437	if (retval < 0)438		goto error;439 440	kdebug("- start_code  %lx", current->mm->start_code);441	kdebug("- end_code    %lx", current->mm->end_code);442	kdebug("- start_data  %lx", current->mm->start_data);443	kdebug("- end_data    %lx", current->mm->end_data);444	kdebug("- start_brk   %lx", current->mm->start_brk);445	kdebug("- brk         %lx", current->mm->brk);446	kdebug("- start_stack %lx", current->mm->start_stack);447 448#ifdef ELF_FDPIC_PLAT_INIT449	/*450	 * The ABI may specify that certain registers be set up in special451	 * ways (on i386 %edx is the address of a DT_FINI function, for452	 * example.  This macro performs whatever initialization to453	 * the regs structure is required.454	 */455	dynaddr = interp_params.dynamic_addr ?: exec_params.dynamic_addr;456	ELF_FDPIC_PLAT_INIT(regs, exec_params.map_addr, interp_params.map_addr,457			    dynaddr);458#endif459 460	finalize_exec(bprm);461	/* everything is now ready... get the userspace context ready to roll */462	entryaddr = interp_params.entry_addr ?: exec_params.entry_addr;463	start_thread(regs, entryaddr, current->mm->start_stack);464 465	retval = 0;466 467error:468	if (interpreter)469		fput(interpreter);470	kfree(interpreter_name);471	kfree(exec_params.phdrs);472	kfree(exec_params.loadmap);473	kfree(interp_params.phdrs);474	kfree(interp_params.loadmap);475	return retval;476}477 478/*****************************************************************************/479 480#ifndef ELF_BASE_PLATFORM481/*482 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.483 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value484 * will be copied to the user stack in the same manner as AT_PLATFORM.485 */486#define ELF_BASE_PLATFORM NULL487#endif488 489/*490 * present useful information to the program by shovelling it onto the new491 * process's stack492 */493static int create_elf_fdpic_tables(struct linux_binprm *bprm,494				   struct mm_struct *mm,495				   struct elf_fdpic_params *exec_params,496				   struct elf_fdpic_params *interp_params)497{498	const struct cred *cred = current_cred();499	unsigned long sp, csp, nitems;500	elf_caddr_t __user *argv, *envp;501	size_t platform_len = 0, len;502	char *k_platform, *k_base_platform;503	char __user *u_platform, *u_base_platform, *p;504	int loop;505	unsigned long flags = 0;506	int ei_index;507	elf_addr_t *elf_info;508 509#ifdef CONFIG_MMU510	/* In some cases (e.g. Hyper-Threading), we want to avoid L1 evictions511	 * by the processes running on the same package. One thing we can do is512	 * to shuffle the initial stack for them, so we give the architecture513	 * an opportunity to do so here.514	 */515	sp = arch_align_stack(bprm->p);516#else517	sp = mm->start_stack;518 519	/* stack the program arguments and environment */520	if (transfer_args_to_stack(bprm, &sp) < 0)521		return -EFAULT;522	sp &= ~15;523#endif524 525	/*526	 * If this architecture has a platform capability string, copy it527	 * to userspace.  In some cases (Sparc), this info is impossible528	 * for userspace to get any other way, in others (i386) it is529	 * merely difficult.530	 */531	k_platform = ELF_PLATFORM;532	u_platform = NULL;533 534	if (k_platform) {535		platform_len = strlen(k_platform) + 1;536		sp -= platform_len;537		u_platform = (char __user *) sp;538		if (copy_to_user(u_platform, k_platform, platform_len) != 0)539			return -EFAULT;540	}541 542	/*543	 * If this architecture has a "base" platform capability544	 * string, copy it to userspace.545	 */546	k_base_platform = ELF_BASE_PLATFORM;547	u_base_platform = NULL;548 549	if (k_base_platform) {550		platform_len = strlen(k_base_platform) + 1;551		sp -= platform_len;552		u_base_platform = (char __user *) sp;553		if (copy_to_user(u_base_platform, k_base_platform, platform_len) != 0)554			return -EFAULT;555	}556 557	sp &= ~7UL;558 559	/* stack the load map(s) */560	len = sizeof(struct elf_fdpic_loadmap);561	len += sizeof(struct elf_fdpic_loadseg) * exec_params->loadmap->nsegs;562	sp = (sp - len) & ~7UL;563	exec_params->map_addr = sp;564 565	if (copy_to_user((void __user *) sp, exec_params->loadmap, len) != 0)566		return -EFAULT;567 568	current->mm->context.exec_fdpic_loadmap = (unsigned long) sp;569 570	if (interp_params->loadmap) {571		len = sizeof(struct elf_fdpic_loadmap);572		len += sizeof(struct elf_fdpic_loadseg) *573			interp_params->loadmap->nsegs;574		sp = (sp - len) & ~7UL;575		interp_params->map_addr = sp;576 577		if (copy_to_user((void __user *) sp, interp_params->loadmap,578				 len) != 0)579			return -EFAULT;580 581		current->mm->context.interp_fdpic_loadmap = (unsigned long) sp;582	}583 584	/* force 16 byte _final_ alignment here for generality */585#define DLINFO_ITEMS 15586 587	nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) +588		(k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH;589 590	if (bprm->have_execfd)591		nitems++;592#ifdef ELF_HWCAP2593	nitems++;594#endif595 596	csp = sp;597	sp -= nitems * 2 * sizeof(unsigned long);598	sp -= (bprm->envc + 1) * sizeof(char *);	/* envv[] */599	sp -= (bprm->argc + 1) * sizeof(char *);	/* argv[] */600	sp -= 1 * sizeof(unsigned long);		/* argc */601 602	csp -= sp & 15UL;603	sp -= sp & 15UL;604 605	/* Create the ELF interpreter info */606	elf_info = (elf_addr_t *)mm->saved_auxv;607	/* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */608#define NEW_AUX_ENT(id, val) \609	do { \610		*elf_info++ = id; \611		*elf_info++ = val; \612	} while (0)613 614#ifdef ARCH_DLINFO615	/*616	 * ARCH_DLINFO must come first so PPC can do its special alignment of617	 * AUXV.618	 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in619	 * ARCH_DLINFO changes620	 */621	ARCH_DLINFO;622#endif623	NEW_AUX_ENT(AT_HWCAP,	ELF_HWCAP);624#ifdef ELF_HWCAP2625	NEW_AUX_ENT(AT_HWCAP2,	ELF_HWCAP2);626#endif627	NEW_AUX_ENT(AT_PAGESZ,	PAGE_SIZE);628	NEW_AUX_ENT(AT_CLKTCK,	CLOCKS_PER_SEC);629	NEW_AUX_ENT(AT_PHDR,	exec_params->ph_addr);630	NEW_AUX_ENT(AT_PHENT,	sizeof(struct elf_phdr));631	NEW_AUX_ENT(AT_PHNUM,	exec_params->hdr.e_phnum);632	NEW_AUX_ENT(AT_BASE,	interp_params->elfhdr_addr);633	if (bprm->interp_flags & BINPRM_FLAGS_PRESERVE_ARGV0)634		flags |= AT_FLAGS_PRESERVE_ARGV0;635	NEW_AUX_ENT(AT_FLAGS,	flags);636	NEW_AUX_ENT(AT_ENTRY,	exec_params->entry_addr);637	NEW_AUX_ENT(AT_UID,	(elf_addr_t) from_kuid_munged(cred->user_ns, cred->uid));638	NEW_AUX_ENT(AT_EUID,	(elf_addr_t) from_kuid_munged(cred->user_ns, cred->euid));639	NEW_AUX_ENT(AT_GID,	(elf_addr_t) from_kgid_munged(cred->user_ns, cred->gid));640	NEW_AUX_ENT(AT_EGID,	(elf_addr_t) from_kgid_munged(cred->user_ns, cred->egid));641	NEW_AUX_ENT(AT_SECURE,	bprm->secureexec);642	NEW_AUX_ENT(AT_EXECFN,	bprm->exec);643	if (k_platform)644		NEW_AUX_ENT(AT_PLATFORM,645			    (elf_addr_t)(unsigned long)u_platform);646	if (k_base_platform)647		NEW_AUX_ENT(AT_BASE_PLATFORM,648			    (elf_addr_t)(unsigned long)u_base_platform);649	if (bprm->have_execfd)650		NEW_AUX_ENT(AT_EXECFD, bprm->execfd);651#undef NEW_AUX_ENT652	/* AT_NULL is zero; clear the rest too */653	memset(elf_info, 0, (char *)mm->saved_auxv +654	       sizeof(mm->saved_auxv) - (char *)elf_info);655 656	/* And advance past the AT_NULL entry.  */657	elf_info += 2;658 659	ei_index = elf_info - (elf_addr_t *)mm->saved_auxv;660	csp -= ei_index * sizeof(elf_addr_t);661 662	/* Put the elf_info on the stack in the right place.  */663	if (copy_to_user((void __user *)csp, mm->saved_auxv,664			 ei_index * sizeof(elf_addr_t)))665		return -EFAULT;666 667	/* allocate room for argv[] and envv[] */668	csp -= (bprm->envc + 1) * sizeof(elf_caddr_t);669	envp = (elf_caddr_t __user *) csp;670	csp -= (bprm->argc + 1) * sizeof(elf_caddr_t);671	argv = (elf_caddr_t __user *) csp;672 673	/* stack argc */674	csp -= sizeof(unsigned long);675	if (put_user(bprm->argc, (unsigned long __user *) csp))676		return -EFAULT;677 678	BUG_ON(csp != sp);679 680	/* fill in the argv[] array */681#ifdef CONFIG_MMU682	current->mm->arg_start = bprm->p;683#else684	current->mm->arg_start = current->mm->start_stack -685		(MAX_ARG_PAGES * PAGE_SIZE - bprm->p);686#endif687 688	p = (char __user *) current->mm->arg_start;689	for (loop = bprm->argc; loop > 0; loop--) {690		if (put_user((elf_caddr_t) p, argv++))691			return -EFAULT;692		len = strnlen_user(p, MAX_ARG_STRLEN);693		if (!len || len > MAX_ARG_STRLEN)694			return -EINVAL;695		p += len;696	}697	if (put_user(NULL, argv))698		return -EFAULT;699	current->mm->arg_end = (unsigned long) p;700 701	/* fill in the envv[] array */702	current->mm->env_start = (unsigned long) p;703	for (loop = bprm->envc; loop > 0; loop--) {704		if (put_user((elf_caddr_t)(unsigned long) p, envp++))705			return -EFAULT;706		len = strnlen_user(p, MAX_ARG_STRLEN);707		if (!len || len > MAX_ARG_STRLEN)708			return -EINVAL;709		p += len;710	}711	if (put_user(NULL, envp))712		return -EFAULT;713	current->mm->env_end = (unsigned long) p;714 715	mm->start_stack = (unsigned long) sp;716	return 0;717}718 719/*****************************************************************************/720/*721 * load the appropriate binary image (executable or interpreter) into memory722 * - we assume no MMU is available723 * - if no other PIC bits are set in params->hdr->e_flags724 *   - we assume that the LOADable segments in the binary are independently relocatable725 *   - we assume R/O executable segments are shareable726 * - else727 *   - we assume the loadable parts of the image to require fixed displacement728 *   - the image is not shareable729 */730static int elf_fdpic_map_file(struct elf_fdpic_params *params,731			      struct file *file,732			      struct mm_struct *mm,733			      const char *what)734{735	struct elf_fdpic_loadmap *loadmap;736#ifdef CONFIG_MMU737	struct elf_fdpic_loadseg *mseg;738	unsigned long load_addr;739#endif740	struct elf_fdpic_loadseg *seg;741	struct elf_phdr *phdr;742	unsigned nloads, tmp;743	unsigned long stop;744	int loop, ret;745 746	/* allocate a load map table */747	nloads = 0;748	for (loop = 0; loop < params->hdr.e_phnum; loop++)749		if (params->phdrs[loop].p_type == PT_LOAD)750			nloads++;751 752	if (nloads == 0)753		return -ELIBBAD;754 755	loadmap = kzalloc(struct_size(loadmap, segs, nloads), GFP_KERNEL);756	if (!loadmap)757		return -ENOMEM;758 759	params->loadmap = loadmap;760 761	loadmap->version = ELF_FDPIC_LOADMAP_VERSION;762	loadmap->nsegs = nloads;763 764	/* map the requested LOADs into the memory space */765	switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {766	case ELF_FDPIC_FLAG_CONSTDISP:767	case ELF_FDPIC_FLAG_CONTIGUOUS:768#ifndef CONFIG_MMU769		ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm);770		if (ret < 0)771			return ret;772		break;773#endif774	default:775		ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm);776		if (ret < 0)777			return ret;778		break;779	}780 781	/* map the entry point */782	if (params->hdr.e_entry) {783		seg = loadmap->segs;784		for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {785			if (params->hdr.e_entry >= seg->p_vaddr &&786			    params->hdr.e_entry < seg->p_vaddr + seg->p_memsz) {787				params->entry_addr =788					(params->hdr.e_entry - seg->p_vaddr) +789					seg->addr;790				break;791			}792		}793	}794 795	/* determine where the program header table has wound up if mapped */796	stop = params->hdr.e_phoff;797	stop += params->hdr.e_phnum * sizeof (struct elf_phdr);798	phdr = params->phdrs;799 800	for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {801		if (phdr->p_type != PT_LOAD)802			continue;803 804		if (phdr->p_offset > params->hdr.e_phoff ||805		    phdr->p_offset + phdr->p_filesz < stop)806			continue;807 808		seg = loadmap->segs;809		for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {810			if (phdr->p_vaddr >= seg->p_vaddr &&811			    phdr->p_vaddr + phdr->p_filesz <=812			    seg->p_vaddr + seg->p_memsz) {813				params->ph_addr =814					(phdr->p_vaddr - seg->p_vaddr) +815					seg->addr +816					params->hdr.e_phoff - phdr->p_offset;817				break;818			}819		}820		break;821	}822 823	/* determine where the dynamic section has wound up if there is one */824	phdr = params->phdrs;825	for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {826		if (phdr->p_type != PT_DYNAMIC)827			continue;828 829		seg = loadmap->segs;830		for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {831			if (phdr->p_vaddr >= seg->p_vaddr &&832			    phdr->p_vaddr + phdr->p_memsz <=833			    seg->p_vaddr + seg->p_memsz) {834				Elf_Dyn __user *dyn;835				Elf_Sword d_tag;836 837				params->dynamic_addr =838					(phdr->p_vaddr - seg->p_vaddr) +839					seg->addr;840 841				/* check the dynamic section contains at least842				 * one item, and that the last item is a NULL843				 * entry */844				if (phdr->p_memsz == 0 ||845				    phdr->p_memsz % sizeof(Elf_Dyn) != 0)846					goto dynamic_error;847 848				tmp = phdr->p_memsz / sizeof(Elf_Dyn);849				dyn = (Elf_Dyn __user *)params->dynamic_addr;850				if (get_user(d_tag, &dyn[tmp - 1].d_tag) ||851				    d_tag != 0)852					goto dynamic_error;853				break;854			}855		}856		break;857	}858 859	/* now elide adjacent segments in the load map on MMU linux860	 * - on uClinux the holes between may actually be filled with system861	 *   stuff or stuff from other processes862	 */863#ifdef CONFIG_MMU864	nloads = loadmap->nsegs;865	mseg = loadmap->segs;866	seg = mseg + 1;867	for (loop = 1; loop < nloads; loop++) {868		/* see if we have a candidate for merging */869		if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) {870			load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz);871			if (load_addr == (seg->addr & PAGE_MASK)) {872				mseg->p_memsz +=873					load_addr -874					(mseg->addr + mseg->p_memsz);875				mseg->p_memsz += seg->addr & ~PAGE_MASK;876				mseg->p_memsz += seg->p_memsz;877				loadmap->nsegs--;878				continue;879			}880		}881 882		mseg++;883		if (mseg != seg)884			*mseg = *seg;885	}886#endif887 888	kdebug("Mapped Object [%s]:", what);889	kdebug("- elfhdr   : %lx", params->elfhdr_addr);890	kdebug("- entry    : %lx", params->entry_addr);891	kdebug("- PHDR[]   : %lx", params->ph_addr);892	kdebug("- DYNAMIC[]: %lx", params->dynamic_addr);893	seg = loadmap->segs;894	for (loop = 0; loop < loadmap->nsegs; loop++, seg++)895		kdebug("- LOAD[%d] : %08llx-%08llx [va=%llx ms=%llx]",896		       loop,897		       (unsigned long long) seg->addr,898		       (unsigned long long) seg->addr + seg->p_memsz - 1,899		       (unsigned long long) seg->p_vaddr,900		       (unsigned long long) seg->p_memsz);901 902	return 0;903 904dynamic_error:905	printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n",906	       what, file_inode(file)->i_ino);907	return -ELIBBAD;908}909 910/*****************************************************************************/911/*912 * map a file with constant displacement under uClinux913 */914#ifndef CONFIG_MMU915static int elf_fdpic_map_file_constdisp_on_uclinux(916	struct elf_fdpic_params *params,917	struct file *file,918	struct mm_struct *mm)919{920	struct elf_fdpic_loadseg *seg;921	struct elf_phdr *phdr;922	unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0;923	int loop, ret;924 925	load_addr = params->load_addr;926	seg = params->loadmap->segs;927 928	/* determine the bounds of the contiguous overall allocation we must929	 * make */930	phdr = params->phdrs;931	for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {932		if (params->phdrs[loop].p_type != PT_LOAD)933			continue;934 935		if (base > phdr->p_vaddr)936			base = phdr->p_vaddr;937		if (top < phdr->p_vaddr + phdr->p_memsz)938			top = phdr->p_vaddr + phdr->p_memsz;939	}940 941	/* allocate one big anon block for everything */942	maddr = vm_mmap(NULL, load_addr, top - base,943			PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE, 0);944	if (IS_ERR_VALUE(maddr))945		return (int) maddr;946 947	if (load_addr != 0)948		load_addr += PAGE_ALIGN(top - base);949 950	/* and then load the file segments into it */951	phdr = params->phdrs;952	for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {953		if (params->phdrs[loop].p_type != PT_LOAD)954			continue;955 956		seg->addr = maddr + (phdr->p_vaddr - base);957		seg->p_vaddr = phdr->p_vaddr;958		seg->p_memsz = phdr->p_memsz;959 960		ret = read_code(file, seg->addr, phdr->p_offset,961				       phdr->p_filesz);962		if (ret < 0)963			return ret;964 965		/* map the ELF header address if in this segment */966		if (phdr->p_offset == 0)967			params->elfhdr_addr = seg->addr;968 969		/* clear any space allocated but not loaded */970		if (phdr->p_filesz < phdr->p_memsz) {971			if (clear_user((void *) (seg->addr + phdr->p_filesz),972				       phdr->p_memsz - phdr->p_filesz))973				return -EFAULT;974		}975 976		if (mm) {977			if (phdr->p_flags & PF_X) {978				if (!mm->start_code) {979					mm->start_code = seg->addr;980					mm->end_code = seg->addr +981						phdr->p_memsz;982				}983			} else if (!mm->start_data) {984				mm->start_data = seg->addr;985				mm->end_data = seg->addr + phdr->p_memsz;986			}987		}988 989		seg++;990	}991 992	return 0;993}994#endif995 996/*****************************************************************************/997/*998 * map a binary by direct mmap() of the individual PT_LOAD segments999 */1000static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,1001					     struct file *file,1002					     struct mm_struct *mm)1003{1004	struct elf_fdpic_loadseg *seg;1005	struct elf_phdr *phdr;1006	unsigned long load_addr, delta_vaddr;1007	int loop, dvset;1008 1009	load_addr = params->load_addr;1010	delta_vaddr = 0;1011	dvset = 0;1012 1013	seg = params->loadmap->segs;1014 1015	/* deal with each load segment separately */1016	phdr = params->phdrs;1017	for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {1018		unsigned long maddr, disp, excess, excess1;1019		int prot = 0, flags;1020 1021		if (phdr->p_type != PT_LOAD)1022			continue;1023 1024		kdebug("[LOAD] va=%lx of=%lx fs=%lx ms=%lx",1025		       (unsigned long) phdr->p_vaddr,1026		       (unsigned long) phdr->p_offset,1027		       (unsigned long) phdr->p_filesz,1028		       (unsigned long) phdr->p_memsz);1029 1030		/* determine the mapping parameters */1031		if (phdr->p_flags & PF_R) prot |= PROT_READ;1032		if (phdr->p_flags & PF_W) prot |= PROT_WRITE;1033		if (phdr->p_flags & PF_X) prot |= PROT_EXEC;1034 1035		flags = MAP_PRIVATE;1036		maddr = 0;1037 1038		switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {1039		case ELF_FDPIC_FLAG_INDEPENDENT:1040			/* PT_LOADs are independently locatable */1041			break;1042 1043		case ELF_FDPIC_FLAG_HONOURVADDR:1044			/* the specified virtual address must be honoured */1045			maddr = phdr->p_vaddr;1046			flags |= MAP_FIXED;1047			break;1048 1049		case ELF_FDPIC_FLAG_CONSTDISP:1050			/* constant displacement1051			 * - can be mapped anywhere, but must be mapped as a1052			 *   unit1053			 */1054			if (!dvset) {1055				maddr = load_addr;1056				delta_vaddr = phdr->p_vaddr;1057				dvset = 1;1058			} else {1059				maddr = load_addr + phdr->p_vaddr - delta_vaddr;1060				flags |= MAP_FIXED;1061			}1062			break;1063 1064		case ELF_FDPIC_FLAG_CONTIGUOUS:1065			/* contiguity handled later */1066			break;1067 1068		default:1069			BUG();1070		}1071 1072		maddr &= PAGE_MASK;1073 1074		/* create the mapping */1075		disp = phdr->p_vaddr & ~PAGE_MASK;1076		maddr = vm_mmap(file, maddr, phdr->p_memsz + disp, prot, flags,1077				phdr->p_offset - disp);1078 1079		kdebug("mmap[%d] <file> sz=%llx pr=%x fl=%x of=%llx --> %08lx",1080		       loop, (unsigned long long) phdr->p_memsz + disp,1081		       prot, flags, (unsigned long long) phdr->p_offset - disp,1082		       maddr);1083 1084		if (IS_ERR_VALUE(maddr))1085			return (int) maddr;1086 1087		if ((params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) ==1088		    ELF_FDPIC_FLAG_CONTIGUOUS)1089			load_addr += PAGE_ALIGN(phdr->p_memsz + disp);1090 1091		seg->addr = maddr + disp;1092		seg->p_vaddr = phdr->p_vaddr;1093		seg->p_memsz = phdr->p_memsz;1094 1095		/* map the ELF header address if in this segment */1096		if (phdr->p_offset == 0)1097			params->elfhdr_addr = seg->addr;1098 1099		/* clear the bit between beginning of mapping and beginning of1100		 * PT_LOAD */1101		if (prot & PROT_WRITE && disp > 0) {1102			kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp);1103			if (clear_user((void __user *) maddr, disp))1104				return -EFAULT;1105			maddr += disp;1106		}1107 1108		/* clear any space allocated but not loaded1109		 * - on uClinux we can just clear the lot1110		 * - on MMU linux we'll get a SIGBUS beyond the last page1111		 *   extant in the file1112		 */1113		excess = phdr->p_memsz - phdr->p_filesz;1114		excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);1115 1116#ifdef CONFIG_MMU1117		if (excess > excess1) {1118			unsigned long xaddr = maddr + phdr->p_filesz + excess1;1119			unsigned long xmaddr;1120 1121			flags |= MAP_FIXED | MAP_ANONYMOUS;1122			xmaddr = vm_mmap(NULL, xaddr, excess - excess1,1123					 prot, flags, 0);1124 1125			kdebug("mmap[%d] <anon>"1126			       " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",1127			       loop, xaddr, excess - excess1, prot, flags,1128			       xmaddr);1129 1130			if (xmaddr != xaddr)1131				return -ENOMEM;1132		}1133 1134		if (prot & PROT_WRITE && excess1 > 0) {1135			kdebug("clear[%d] ad=%lx sz=%lx",1136			       loop, maddr + phdr->p_filesz, excess1);1137			if (clear_user((void __user *) maddr + phdr->p_filesz,1138				       excess1))1139				return -EFAULT;1140		}1141 1142#else1143		if (excess > 0) {1144			kdebug("clear[%d] ad=%llx sz=%lx", loop,1145			       (unsigned long long) maddr + phdr->p_filesz,1146			       excess);1147			if (clear_user((void *) maddr + phdr->p_filesz, excess))1148				return -EFAULT;1149		}1150#endif1151 1152		if (mm) {1153			if (phdr->p_flags & PF_X) {1154				if (!mm->start_code) {1155					mm->start_code = maddr;1156					mm->end_code = maddr + phdr->p_memsz;1157				}1158			} else if (!mm->start_data) {1159				mm->start_data = maddr;1160				mm->end_data = maddr + phdr->p_memsz;1161			}1162		}1163 1164		seg++;1165	}1166 1167	return 0;1168}1169 1170/*****************************************************************************/1171/*1172 * ELF-FDPIC core dumper1173 *1174 * Modelled on fs/exec.c:aout_core_dump()1175 * Jeremy Fitzhardinge <jeremy@sw.oz.au>1176 *1177 * Modelled on fs/binfmt_elf.c core dumper1178 */1179#ifdef CONFIG_ELF_CORE1180 1181struct elf_prstatus_fdpic1182{1183	struct elf_prstatus_common	common;1184	elf_gregset_t pr_reg;	/* GP registers */1185	/* When using FDPIC, the loadmap addresses need to be communicated1186	 * to GDB in order for GDB to do the necessary relocations.  The1187	 * fields (below) used to communicate this information are placed1188	 * immediately after ``pr_reg'', so that the loadmap addresses may1189	 * be viewed as part of the register set if so desired.1190	 */1191	unsigned long pr_exec_fdpic_loadmap;1192	unsigned long pr_interp_fdpic_loadmap;1193	int pr_fpvalid;		/* True if math co-processor being used.  */1194};1195 1196/* An ELF note in memory */1197struct memelfnote1198{1199	const char *name;1200	int type;1201	unsigned int datasz;1202	void *data;1203};1204 1205static int notesize(struct memelfnote *en)1206{1207	int sz;1208 1209	sz = sizeof(struct elf_note);1210	sz += roundup(strlen(en->name) + 1, 4);1211	sz += roundup(en->datasz, 4);1212 1213	return sz;1214}1215 1216/* #define DEBUG */1217 1218static int writenote(struct memelfnote *men, struct coredump_params *cprm)1219{1220	struct elf_note en;1221	en.n_namesz = strlen(men->name) + 1;1222	en.n_descsz = men->datasz;1223	en.n_type = men->type;1224 1225	return dump_emit(cprm, &en, sizeof(en)) &&1226		dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) &&1227		dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4);1228}1229 1230static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)1231{1232	memcpy(elf->e_ident, ELFMAG, SELFMAG);1233	elf->e_ident[EI_CLASS] = ELF_CLASS;1234	elf->e_ident[EI_DATA] = ELF_DATA;1235	elf->e_ident[EI_VERSION] = EV_CURRENT;1236	elf->e_ident[EI_OSABI] = ELF_OSABI;1237	memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);1238 1239	elf->e_type = ET_CORE;1240	elf->e_machine = ELF_ARCH;1241	elf->e_version = EV_CURRENT;1242	elf->e_entry = 0;1243	elf->e_phoff = sizeof(struct elfhdr);1244	elf->e_shoff = 0;1245	elf->e_flags = ELF_FDPIC_CORE_EFLAGS;1246	elf->e_ehsize = sizeof(struct elfhdr);1247	elf->e_phentsize = sizeof(struct elf_phdr);1248	elf->e_phnum = segs;1249	elf->e_shentsize = 0;1250	elf->e_shnum = 0;1251	elf->e_shstrndx = 0;1252	return;1253}1254 1255static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)1256{1257	phdr->p_type = PT_NOTE;1258	phdr->p_offset = offset;1259	phdr->p_vaddr = 0;1260	phdr->p_paddr = 0;1261	phdr->p_filesz = sz;1262	phdr->p_memsz = 0;1263	phdr->p_flags = 0;1264	phdr->p_align = 4;1265	return;1266}1267 1268static inline void fill_note(struct memelfnote *note, const char *name, int type,1269		unsigned int sz, void *data)1270{1271	note->name = name;1272	note->type = type;1273	note->datasz = sz;1274	note->data = data;1275	return;1276}1277 1278/*1279 * fill up all the fields in prstatus from the given task struct, except1280 * registers which need to be filled up separately.1281 */1282static void fill_prstatus(struct elf_prstatus_common *prstatus,1283			  struct task_struct *p, long signr)1284{1285	prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;1286	prstatus->pr_sigpend = p->pending.signal.sig[0];1287	prstatus->pr_sighold = p->blocked.sig[0];1288	rcu_read_lock();1289	prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));1290	rcu_read_unlock();1291	prstatus->pr_pid = task_pid_vnr(p);1292	prstatus->pr_pgrp = task_pgrp_vnr(p);1293	prstatus->pr_sid = task_session_vnr(p);1294	if (thread_group_leader(p)) {1295		struct task_cputime cputime;1296 1297		/*1298		 * This is the record for the group leader.  It shows the1299		 * group-wide total, not its individual thread total.1300		 */1301		thread_group_cputime(p, &cputime);1302		prstatus->pr_utime = ns_to_kernel_old_timeval(cputime.utime);1303		prstatus->pr_stime = ns_to_kernel_old_timeval(cputime.stime);1304	} else {1305		u64 utime, stime;1306 1307		task_cputime(p, &utime, &stime);1308		prstatus->pr_utime = ns_to_kernel_old_timeval(utime);1309		prstatus->pr_stime = ns_to_kernel_old_timeval(stime);1310	}1311	prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime);1312	prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime);1313}1314 1315static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,1316		       struct mm_struct *mm)1317{1318	const struct cred *cred;1319	unsigned int i, len;1320	unsigned int state;1321 1322	/* first copy the parameters from user space */1323	memset(psinfo, 0, sizeof(struct elf_prpsinfo));1324 1325	len = mm->arg_end - mm->arg_start;1326	if (len >= ELF_PRARGSZ)1327		len = ELF_PRARGSZ - 1;1328	if (copy_from_user(&psinfo->pr_psargs,1329		           (const char __user *) mm->arg_start, len))1330		return -EFAULT;1331	for (i = 0; i < len; i++)1332		if (psinfo->pr_psargs[i] == 0)1333			psinfo->pr_psargs[i] = ' ';1334	psinfo->pr_psargs[len] = 0;1335 1336	rcu_read_lock();1337	psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));1338	rcu_read_unlock();1339	psinfo->pr_pid = task_pid_vnr(p);1340	psinfo->pr_pgrp = task_pgrp_vnr(p);1341	psinfo->pr_sid = task_session_vnr(p);1342 1343	state = READ_ONCE(p->__state);1344	i = state ? ffz(~state) + 1 : 0;1345	psinfo->pr_state = i;1346	psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];1347	psinfo->pr_zomb = psinfo->pr_sname == 'Z';1348	psinfo->pr_nice = task_nice(p);1349	psinfo->pr_flag = p->flags;1350	rcu_read_lock();1351	cred = __task_cred(p);1352	SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid));1353	SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid));1354	rcu_read_unlock();1355	get_task_comm(psinfo->pr_fname, p);1356 1357	return 0;1358}1359 1360/* Here is the structure in which status of each thread is captured. */1361struct elf_thread_status1362{1363	struct elf_thread_status *next;1364	struct elf_prstatus_fdpic prstatus;	/* NT_PRSTATUS */1365	elf_fpregset_t fpu;		/* NT_PRFPREG */1366	struct memelfnote notes[2];1367	int num_notes;1368};1369 1370/*1371 * In order to add the specific thread information for the elf file format,1372 * we need to keep a linked list of every thread's pr_status and then create1373 * a single section for them in the final core file.1374 */1375static struct elf_thread_status *elf_dump_thread_status(long signr, struct task_struct *p, int *sz)1376{1377	const struct user_regset_view *view = task_user_regset_view(p);1378	struct elf_thread_status *t;1379	int i, ret;1380 1381	t = kzalloc(sizeof(struct elf_thread_status), GFP_KERNEL);1382	if (!t)1383		return t;1384 1385	fill_prstatus(&t->prstatus.common, p, signr);1386	t->prstatus.pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap;1387	t->prstatus.pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap;1388	regset_get(p, &view->regsets[0],1389		   sizeof(t->prstatus.pr_reg), &t->prstatus.pr_reg);1390 1391	fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),1392		  &t->prstatus);1393	t->num_notes++;1394	*sz += notesize(&t->notes[0]);1395 1396	for (i = 1; i < view->n; ++i) {1397		const struct user_regset *regset = &view->regsets[i];1398		if (regset->core_note_type != NT_PRFPREG)1399			continue;1400		if (regset->active && regset->active(p, regset) <= 0)1401			continue;1402		ret = regset_get(p, regset, sizeof(t->fpu), &t->fpu);1403		if (ret >= 0)1404			t->prstatus.pr_fpvalid = 1;1405		break;1406	}1407 1408	if (t->prstatus.pr_fpvalid) {1409		fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),1410			  &t->fpu);1411		t->num_notes++;1412		*sz += notesize(&t->notes[1]);1413	}1414	return t;1415}1416 1417static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,1418			     elf_addr_t e_shoff, int segs)1419{1420	elf->e_shoff = e_shoff;1421	elf->e_shentsize = sizeof(*shdr4extnum);1422	elf->e_shnum = 1;1423	elf->e_shstrndx = SHN_UNDEF;1424 1425	memset(shdr4extnum, 0, sizeof(*shdr4extnum));1426 1427	shdr4extnum->sh_type = SHT_NULL;1428	shdr4extnum->sh_size = elf->e_shnum;1429	shdr4extnum->sh_link = elf->e_shstrndx;1430	shdr4extnum->sh_info = segs;1431}1432 1433/*1434 * dump the segments for an MMU process1435 */1436static bool elf_fdpic_dump_segments(struct coredump_params *cprm,1437				    struct core_vma_metadata *vma_meta,1438				    int vma_count)1439{1440	int i;1441 1442	for (i = 0; i < vma_count; i++) {1443		struct core_vma_metadata *meta = vma_meta + i;1444 1445		if (!dump_user_range(cprm, meta->start, meta->dump_size))1446			return false;1447	}1448	return true;1449}1450 1451/*1452 * Actual dumper1453 *1454 * This is a two-pass process; first we find the offsets of the bits,1455 * and then they are actually written out.  If we run out of core limit1456 * we just truncate.1457 */1458static int elf_fdpic_core_dump(struct coredump_params *cprm)1459{1460	int has_dumped = 0;1461	int segs;1462	int i;1463	struct elfhdr *elf = NULL;1464	loff_t offset = 0, dataoff;1465	struct memelfnote psinfo_note, auxv_note;1466	struct elf_prpsinfo *psinfo = NULL;	/* NT_PRPSINFO */1467	struct elf_thread_status *thread_list = NULL;1468	int thread_status_size = 0;1469	elf_addr_t *auxv;1470	struct elf_phdr *phdr4note = NULL;1471	struct elf_shdr *shdr4extnum = NULL;1472	Elf_Half e_phnum;1473	elf_addr_t e_shoff;1474	struct core_thread *ct;1475	struct elf_thread_status *tmp;1476 1477	/* alloc memory for large data structures: too large to be on stack */1478	elf = kmalloc(sizeof(*elf), GFP_KERNEL);1479	if (!elf)1480		goto end_coredump;1481	psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);1482	if (!psinfo)1483		goto end_coredump;1484 1485	for (ct = current->signal->core_state->dumper.next;1486					ct; ct = ct->next) {1487		tmp = elf_dump_thread_status(cprm->siginfo->si_signo,1488					     ct->task, &thread_status_size);1489		if (!tmp)1490			goto end_coredump;1491 1492		tmp->next = thread_list;1493		thread_list = tmp;1494	}1495 1496	/* now collect the dump for the current */1497	tmp = elf_dump_thread_status(cprm->siginfo->si_signo,1498				     current, &thread_status_size);1499	if (!tmp)1500		goto end_coredump;1501	tmp->next = thread_list;1502	thread_list = tmp;1503 1504	segs = cprm->vma_count + elf_core_extra_phdrs(cprm);1505 1506	/* for notes section */1507	segs++;1508 1509	/* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid1510	 * this, kernel supports extended numbering. Have a look at1511	 * include/linux/elf.h for further information. */1512	e_phnum = segs > PN_XNUM ? PN_XNUM : segs;1513 1514	/* Set up header */1515	fill_elf_fdpic_header(elf, e_phnum);1516 1517	has_dumped = 1;1518	/*1519	 * Set up the notes in similar form to SVR4 core dumps made1520	 * with info from their /proc.1521	 */1522 1523	fill_psinfo(psinfo, current->group_leader, current->mm);1524	fill_note(&psinfo_note, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);1525	thread_status_size += notesize(&psinfo_note);1526 1527	auxv = (elf_addr_t *) current->mm->saved_auxv;1528	i = 0;1529	do1530		i += 2;1531	while (auxv[i - 2] != AT_NULL);1532	fill_note(&auxv_note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);1533	thread_status_size += notesize(&auxv_note);1534 1535	offset = sizeof(*elf);				/* ELF header */1536	offset += segs * sizeof(struct elf_phdr);	/* Program headers */1537 1538	/* Write notes phdr entry */1539	phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);1540	if (!phdr4note)1541		goto end_coredump;1542 1543	fill_elf_note_phdr(phdr4note, thread_status_size, offset);1544	offset += thread_status_size;1545 1546	/* Page-align dumped data */1547	dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);1548 1549	offset += cprm->vma_data_size;1550	offset += elf_core_extra_data_size(cprm);1551	e_shoff = offset;1552 1553	if (e_phnum == PN_XNUM) {1554		shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);1555		if (!shdr4extnum)1556			goto end_coredump;1557		fill_extnum_info(elf, shdr4extnum, e_shoff, segs);1558	}1559 1560	offset = dataoff;1561 1562	if (!dump_emit(cprm, elf, sizeof(*elf)))1563		goto end_coredump;1564 1565	if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note)))1566		goto end_coredump;1567 1568	/* write program headers for segments dump */1569	for (i = 0; i < cprm->vma_count; i++) {1570		struct core_vma_metadata *meta = cprm->vma_meta + i;1571		struct elf_phdr phdr;1572		size_t sz;1573 1574		sz = meta->end - meta->start;1575 1576		phdr.p_type = PT_LOAD;1577		phdr.p_offset = offset;1578		phdr.p_vaddr = meta->start;1579		phdr.p_paddr = 0;1580		phdr.p_filesz = meta->dump_size;1581		phdr.p_memsz = sz;1582		offset += phdr.p_filesz;1583		phdr.p_flags = 0;1584		if (meta->flags & VM_READ)1585			phdr.p_flags |= PF_R;1586		if (meta->flags & VM_WRITE)1587			phdr.p_flags |= PF_W;1588		if (meta->flags & VM_EXEC)1589			phdr.p_flags |= PF_X;1590		phdr.p_align = ELF_EXEC_PAGESIZE;1591 1592		if (!dump_emit(cprm, &phdr, sizeof(phdr)))1593			goto end_coredump;1594	}1595 1596	if (!elf_core_write_extra_phdrs(cprm, offset))1597		goto end_coredump;1598 1599	/* write out the notes section */1600	if (!writenote(thread_list->notes, cprm))1601		goto end_coredump;1602	if (!writenote(&psinfo_note, cprm))1603		goto end_coredump;1604	if (!writenote(&auxv_note, cprm))1605		goto end_coredump;1606	for (i = 1; i < thread_list->num_notes; i++)1607		if (!writenote(thread_list->notes + i, cprm))1608			goto end_coredump;1609 1610	/* write out the thread status notes section */1611	for (tmp = thread_list->next; tmp; tmp = tmp->next) {1612		for (i = 0; i < tmp->num_notes; i++)1613			if (!writenote(&tmp->notes[i], cprm))1614				goto end_coredump;1615	}1616 1617	dump_skip_to(cprm, dataoff);1618 1619	if (!elf_fdpic_dump_segments(cprm, cprm->vma_meta, cprm->vma_count))1620		goto end_coredump;1621 1622	if (!elf_core_write_extra_data(cprm))1623		goto end_coredump;1624 1625	if (e_phnum == PN_XNUM) {1626		if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum)))1627			goto end_coredump;1628	}1629 1630	if (cprm->file->f_pos != offset) {1631		/* Sanity check */1632		printk(KERN_WARNING1633		       "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n",1634		       cprm->file->f_pos, offset);1635	}1636 1637end_coredump:1638	while (thread_list) {1639		tmp = thread_list;1640		thread_list = thread_list->next;1641		kfree(tmp);1642	}1643	kfree(phdr4note);1644	kfree(elf);1645	kfree(psinfo);1646	kfree(shdr4extnum);1647	return has_dumped;1648}1649 1650#endif		/* CONFIG_ELF_CORE */1651