arch/x86/ia32/ia32_aout.c - kernel/msm-4.19 - Gitiles

 /*
  *  a.out loader for x86-64
  *
  *  Copyright (C) 1991, 1992, 1996  Linus Torvalds
  *  Hacked together by Andi Kleen
  */

 #include <linux/module.h>

 #include <linux/time.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
 #include <linux/a.out.h>
 #include <linux/errno.h>
 #include <linux/signal.h>
 #include <linux/string.h>
 #include <linux/fs.h>
 #include <linux/file.h>
 #include <linux/stat.h>
 #include <linux/fcntl.h>
 #include <linux/ptrace.h>
 #include <linux/user.h>
 #include <linux/binfmts.h>
 #include <linux/personality.h>
 #include <linux/init.h>
 #include <linux/jiffies.h>
 #include <linux/perf_event.h>
 #include <linux/sched/task_stack.h>

 #include <linux/uaccess.h>
 #include <asm/pgalloc.h>
 #include <asm/cacheflush.h>
 #include <asm/user32.h>
 #include <asm/ia32.h>

 #undef WARN_OLD

 static int load_aout_binary(struct linux_binprm *);
 static int load_aout_library(struct file *);

 #ifdef CONFIG_COREDUMP
 static int aout_core_dump(struct coredump_params *);

 static unsigned long get_dr(int n)
 {
 	struct perf_event *bp = current->thread.ptrace_bps[n];
 	return bp ? bp->hw.info.address : 0;
 }

 /*
  * fill in the user structure for a core dump..
  */
 static void dump_thread32(struct pt_regs *regs, struct user32 *dump)
 {
 	u32 fs, gs;
 	memset(dump, 0, sizeof(*dump));

 /* changed the size calculations - should hopefully work better. lbt */
 	dump->magic = CMAGIC;
 	dump->start_code = 0;
 	dump->start_stack = regs->sp & ~(PAGE_SIZE - 1);
 	dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
 	dump->u_dsize = ((unsigned long)
 			 (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT;
 	dump->u_dsize -= dump->u_tsize;
 	dump->u_debugreg[0] = get_dr(0);
 	dump->u_debugreg[1] = get_dr(1);
 	dump->u_debugreg[2] = get_dr(2);
 	dump->u_debugreg[3] = get_dr(3);
 	dump->u_debugreg[6] = current->thread.debugreg6;
 	dump->u_debugreg[7] = current->thread.ptrace_dr7;

 	if (dump->start_stack < 0xc0000000) {
 		unsigned long tmp;

 		tmp = (unsigned long) (0xc0000000 - dump->start_stack);
 		dump->u_ssize = tmp >> PAGE_SHIFT;
 	}

 	dump->regs.ebx = regs->bx;
 	dump->regs.ecx = regs->cx;
 	dump->regs.edx = regs->dx;
 	dump->regs.esi = regs->si;
 	dump->regs.edi = regs->di;
 	dump->regs.ebp = regs->bp;
 	dump->regs.eax = regs->ax;
 	dump->regs.ds = current->thread.ds;
 	dump->regs.es = current->thread.es;
 	savesegment(fs, fs);
 	dump->regs.fs = fs;
 	savesegment(gs, gs);
 	dump->regs.gs = gs;
 	dump->regs.orig_eax = regs->orig_ax;
 	dump->regs.eip = regs->ip;
 	dump->regs.cs = regs->cs;
 	dump->regs.eflags = regs->flags;
 	dump->regs.esp = regs->sp;
 	dump->regs.ss = regs->ss;

 #if 1 /* FIXME */
 	dump->u_fpvalid = 0;
 #else
 	dump->u_fpvalid = dump_fpu(regs, &dump->i387);
 #endif
 }

 #endif

 static struct linux_binfmt aout_format = {
 	.module		= THIS_MODULE,
 	.load_binary	= load_aout_binary,
 	.load_shlib	= load_aout_library,
 #ifdef CONFIG_COREDUMP
 	.core_dump	= aout_core_dump,
 #endif
 	.min_coredump	= PAGE_SIZE
 };

 static int set_brk(unsigned long start, unsigned long end)
 {
 	start = PAGE_ALIGN(start);
 	end = PAGE_ALIGN(end);
 	if (end <= start)
 		return 0;
 	return vm_brk(start, end - start);
 }

 #ifdef CONFIG_COREDUMP
 /*
  * These are the only things you should do on a core-file: use only these
  * macros to write out all the necessary info.
  */

 #include <linux/coredump.h>

 #define START_DATA(u)	(u.u_tsize << PAGE_SHIFT)
 #define START_STACK(u)	(u.start_stack)

 /*
  * Routine writes a core dump image in the current directory.
  * Currently only a stub-function.
  *
  * Note that setuid/setgid files won't make a core-dump if the uid/gid
  * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable"
  * field, which also makes sure the core-dumps won't be recursive if the
  * dumping of the process results in another error..
  */

 static int aout_core_dump(struct coredump_params *cprm)
 {
 	mm_segment_t fs;
 	int has_dumped = 0;
 	unsigned long dump_start, dump_size;
 	struct user32 dump;

 	fs = get_fs();
 	set_fs(KERNEL_DS);
 	has_dumped = 1;
 	strncpy(dump.u_comm, current->comm, sizeof(current->comm));
 	dump.u_ar0 = offsetof(struct user32, regs);
 	dump.signal = cprm->siginfo->si_signo;
 	dump_thread32(cprm->regs, &dump);

 	/*
 	 * If the size of the dump file exceeds the rlimit, then see
 	 * what would happen if we wrote the stack, but not the data
 	 * area.
 	 */
 	if ((dump.u_dsize + dump.u_ssize + 1) * PAGE_SIZE > cprm->limit)
 		dump.u_dsize = 0;

 	/* Make sure we have enough room to write the stack and data areas. */
 	if ((dump.u_ssize + 1) * PAGE_SIZE > cprm->limit)
 		dump.u_ssize = 0;

 	/* make sure we actually have a data and stack area to dump */
 	set_fs(USER_DS);
 	if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_DATA(dump),
 		       dump.u_dsize << PAGE_SHIFT))
 		dump.u_dsize = 0;
 	if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_STACK(dump),
 		       dump.u_ssize << PAGE_SHIFT))
 		dump.u_ssize = 0;

 	set_fs(KERNEL_DS);
 	/* struct user */
 	if (!dump_emit(cprm, &dump, sizeof(dump)))
 		goto end_coredump;
 	/* Now dump all of the user data.  Include malloced stuff as well */
 	if (!dump_skip(cprm, PAGE_SIZE - sizeof(dump)))
 		goto end_coredump;
 	/* now we start writing out the user space info */
 	set_fs(USER_DS);
 	/* Dump the data area */
 	if (dump.u_dsize != 0) {
 		dump_start = START_DATA(dump);
 		dump_size = dump.u_dsize << PAGE_SHIFT;
 		if (!dump_emit(cprm, (void *)dump_start, dump_size))
 			goto end_coredump;
 	}
 	/* Now prepare to dump the stack area */
 	if (dump.u_ssize != 0) {
 		dump_start = START_STACK(dump);
 		dump_size = dump.u_ssize << PAGE_SHIFT;
 		if (!dump_emit(cprm, (void *)dump_start, dump_size))
 			goto end_coredump;
 	}
 end_coredump:
 	set_fs(fs);
 	return has_dumped;
 }
 #endif

 /*
  * create_aout_tables() parses the env- and arg-strings in new user
  * memory and creates the pointer tables from them, and puts their
  * addresses on the "stack", returning the new stack pointer value.
  */
 static u32 __user *create_aout_tables(char __user *p, struct linux_binprm *bprm)
 {
 	u32 __user *argv, *envp, *sp;
 	int argc = bprm->argc, envc = bprm->envc;

 	sp = (u32 __user *) ((-(unsigned long)sizeof(u32)) & (unsigned long) p);
 	sp -= envc+1;
 	envp = sp;
 	sp -= argc+1;
 	argv = sp;
 	put_user((unsigned long) envp, --sp);
 	put_user((unsigned long) argv, --sp);
 	put_user(argc, --sp);
 	current->mm->arg_start = (unsigned long) p;
 	while (argc-- > 0) {
 		char c;

 		put_user((u32)(unsigned long)p, argv++);
 		do {
 			get_user(c, p++);
 		} while (c);
 	}
 	put_user(0, argv);
 	current->mm->arg_end = current->mm->env_start = (unsigned long) p;
 	while (envc-- > 0) {
 		char c;

 		put_user((u32)(unsigned long)p, envp++);
 		do {
 			get_user(c, p++);
 		} while (c);
 	}
 	put_user(0, envp);
 	current->mm->env_end = (unsigned long) p;
 	return sp;
 }

 /*
  * These are the functions used to load a.out style executables and shared
  * libraries.  There is no binary dependent code anywhere else.
  */
 static int load_aout_binary(struct linux_binprm *bprm)
 {
 	unsigned long error, fd_offset, rlim;
 	struct pt_regs *regs = current_pt_regs();
 	struct exec ex;
 	int retval;

 	ex = *((struct exec *) bprm->buf);		/* exec-header */
 	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
 	     N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) ||
 	    N_TRSIZE(ex) || N_DRSIZE(ex) ||
 	    i_size_read(file_inode(bprm->file)) <
 	    ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
 		return -ENOEXEC;
 	}

 	fd_offset = N_TXTOFF(ex);

 	/* Check initial limits. This avoids letting people circumvent
 	 * size limits imposed on them by creating programs with large
 	 * arrays in the data or bss.
 	 */
 	rlim = rlimit(RLIMIT_DATA);
 	if (rlim >= RLIM_INFINITY)
 		rlim = ~0;
 	if (ex.a_data + ex.a_bss > rlim)
 		return -ENOMEM;

 	/* Flush all traces of the currently running executable */
 	retval = flush_old_exec(bprm);
 	if (retval)
 		return retval;

 	/* OK, This is the point of no return */
 	set_personality(PER_LINUX);
 	set_personality_ia32(false);

 	setup_new_exec(bprm);

 	regs->cs = __USER32_CS;
 	regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 =
 		regs->r13 = regs->r14 = regs->r15 = 0;

 	current->mm->end_code = ex.a_text +
 		(current->mm->start_code = N_TXTADDR(ex));
 	current->mm->end_data = ex.a_data +
 		(current->mm->start_data = N_DATADDR(ex));
 	current->mm->brk = ex.a_bss +
 		(current->mm->start_brk = N_BSSADDR(ex));

 	retval = setup_arg_pages(bprm, IA32_STACK_TOP, EXSTACK_DEFAULT);
 	if (retval < 0)
 		return retval;

 	install_exec_creds(bprm);

 	if (N_MAGIC(ex) == OMAGIC) {
 		unsigned long text_addr, map_size;

 		text_addr = N_TXTADDR(ex);
 		map_size = ex.a_text+ex.a_data;

 		error = vm_brk(text_addr & PAGE_MASK, map_size);

 		if (error)
 			return error;

 		error = read_code(bprm->file, text_addr, 32,
 				  ex.a_text + ex.a_data);
 		if ((signed long)error < 0)
 			return error;
 	} else {
 #ifdef WARN_OLD
 		static unsigned long error_time, error_time2;
 		if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
 		    (N_MAGIC(ex) != NMAGIC) &&
 				time_after(jiffies, error_time2 + 5*HZ)) {
 			printk(KERN_NOTICE "executable not page aligned\n");
 			error_time2 = jiffies;
 		}

 		if ((fd_offset & ~PAGE_MASK) != 0 &&
 			    time_after(jiffies, error_time + 5*HZ)) {
 			printk(KERN_WARNING
 			       "fd_offset is not page aligned. Please convert "
 			       "program: %pD\n",
 			       bprm->file);
 			error_time = jiffies;
 		}
 #endif

 		if (!bprm->file->f_op->mmap || (fd_offset & ~PAGE_MASK) != 0) {
 			error = vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
 			if (error)
 				return error;

 			read_code(bprm->file, N_TXTADDR(ex), fd_offset,
 					ex.a_text+ex.a_data);
 			goto beyond_if;
 		}

 		error = vm_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
 				PROT_READ | PROT_EXEC,
 				MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE |
 				MAP_EXECUTABLE | MAP_32BIT,
 				fd_offset);

 		if (error != N_TXTADDR(ex))
 			return error;

 		error = vm_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
 				PROT_READ | PROT_WRITE | PROT_EXEC,
 				MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE |
 				MAP_EXECUTABLE | MAP_32BIT,
 				fd_offset + ex.a_text);
 		if (error != N_DATADDR(ex))
 			return error;
 	}

 beyond_if:
 	error = set_brk(current->mm->start_brk, current->mm->brk);
 	if (error)
 		return error;

 	set_binfmt(&aout_format);

 	current->mm->start_stack =
 		(unsigned long)create_aout_tables((char __user *)bprm->p, bprm);
 	/* start thread */
 	loadsegment(fs, 0);
 	loadsegment(ds, __USER32_DS);
 	loadsegment(es, __USER32_DS);
 	load_gs_index(0);
 	(regs)->ip = ex.a_entry;
 	(regs)->sp = current->mm->start_stack;
 	(regs)->flags = 0x200;
 	(regs)->cs = __USER32_CS;
 	(regs)->ss = __USER32_DS;
 	regs->r8 = regs->r9 = regs->r10 = regs->r11 =
 	regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
 	set_fs(USER_DS);
 	return 0;
 }

 static int load_aout_library(struct file *file)
 {
 	unsigned long bss, start_addr, len, error;
 	int retval;
 	struct exec ex;


 	retval = -ENOEXEC;
 	error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
 	if (error != sizeof(ex))
 		goto out;

 	/* We come in here for the regular a.out style of shared libraries */
 	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) ||
 	    N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) ||
 	    i_size_read(file_inode(file)) <
 	    ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
 		goto out;
 	}

 	if (N_FLAGS(ex))
 		goto out;

 	/* For  QMAGIC, the starting address is 0x20 into the page.  We mask
 	   this off to get the starting address for the page */

 	start_addr =  ex.a_entry & 0xfffff000;

 	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
 #ifdef WARN_OLD
 		static unsigned long error_time;
 		if (time_after(jiffies, error_time + 5*HZ)) {
 			printk(KERN_WARNING
 			       "N_TXTOFF is not page aligned. Please convert "
 			       "library: %pD\n",
 			       file);
 			error_time = jiffies;
 		}
 #endif
 		retval = vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
 		if (retval)
 			goto out;

 		read_code(file, start_addr, N_TXTOFF(ex),
 			  ex.a_text + ex.a_data);
 		retval = 0;
 		goto out;
 	}
 	/* Now use mmap to map the library into memory. */
 	error = vm_mmap(file, start_addr, ex.a_text + ex.a_data,
 			PROT_READ | PROT_WRITE | PROT_EXEC,
 			MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_32BIT,
 			N_TXTOFF(ex));
 	retval = error;
 	if (error != start_addr)
 		goto out;

 	len = PAGE_ALIGN(ex.a_text + ex.a_data);
 	bss = ex.a_text + ex.a_data + ex.a_bss;
 	if (bss > len) {
 		retval = vm_brk(start_addr + len, bss - len);
 		if (retval)
 			goto out;
 	}
 	retval = 0;
 out:
 	return retval;
 }

 static int __init init_aout_binfmt(void)
 {
 	register_binfmt(&aout_format);
 	return 0;
 }

 static void __exit exit_aout_binfmt(void)
 {
 	unregister_binfmt(&aout_format);
 }

 module_init(init_aout_binfmt);
 module_exit(exit_aout_binfmt);
 MODULE_LICENSE("GPL");
	/*
	* a.out loader for x86-64
	*
	* Copyright (C) 1991, 1992, 1996 Linus Torvalds
	* Hacked together by Andi Kleen
	*/

	#include <linux/module.h>

	#include <linux/time.h>
	#include <linux/kernel.h>
	#include <linux/mm.h>
	#include <linux/mman.h>
	#include <linux/a.out.h>
	#include <linux/errno.h>
	#include <linux/signal.h>
	#include <linux/string.h>
	#include <linux/fs.h>
	#include <linux/file.h>
	#include <linux/stat.h>
	#include <linux/fcntl.h>
	#include <linux/ptrace.h>
	#include <linux/user.h>
	#include <linux/binfmts.h>
	#include <linux/personality.h>
	#include <linux/init.h>
	#include <linux/jiffies.h>
	#include <linux/perf_event.h>
	#include <linux/sched/task_stack.h>

	#include <linux/uaccess.h>
	#include <asm/pgalloc.h>
	#include <asm/cacheflush.h>
	#include <asm/user32.h>
	#include <asm/ia32.h>

	#undef WARN_OLD

	static int load_aout_binary(struct linux_binprm *);
	static int load_aout_library(struct file *);

	#ifdef CONFIG_COREDUMP
	static int aout_core_dump(struct coredump_params *);

	static unsigned long get_dr(int n)
	{
	struct perf_event *bp = current->thread.ptrace_bps[n];
	return bp ? bp->hw.info.address : 0;
	}

	/*
	* fill in the user structure for a core dump..
	*/
	static void dump_thread32(struct pt_regs regs, struct user32 dump)
	{
	u32 fs, gs;
	memset(dump, 0, sizeof(*dump));

	/* changed the size calculations - should hopefully work better. lbt */
	dump->magic = CMAGIC;
	dump->start_code = 0;
	dump->start_stack = regs->sp & ~(PAGE_SIZE - 1);
	dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
	dump->u_dsize = ((unsigned long)
	(current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT;
	dump->u_dsize -= dump->u_tsize;
	dump->u_debugreg[0] = get_dr(0);
	dump->u_debugreg[1] = get_dr(1);
	dump->u_debugreg[2] = get_dr(2);
	dump->u_debugreg[3] = get_dr(3);
	dump->u_debugreg[6] = current->thread.debugreg6;
	dump->u_debugreg[7] = current->thread.ptrace_dr7;

	if (dump->start_stack < 0xc0000000) {
	unsigned long tmp;

	tmp = (unsigned long) (0xc0000000 - dump->start_stack);
	dump->u_ssize = tmp >> PAGE_SHIFT;
	}

	dump->regs.ebx = regs->bx;
	dump->regs.ecx = regs->cx;
	dump->regs.edx = regs->dx;
	dump->regs.esi = regs->si;
	dump->regs.edi = regs->di;
	dump->regs.ebp = regs->bp;
	dump->regs.eax = regs->ax;
	dump->regs.ds = current->thread.ds;
	dump->regs.es = current->thread.es;
	savesegment(fs, fs);
	dump->regs.fs = fs;
	savesegment(gs, gs);
	dump->regs.gs = gs;
	dump->regs.orig_eax = regs->orig_ax;
	dump->regs.eip = regs->ip;
	dump->regs.cs = regs->cs;
	dump->regs.eflags = regs->flags;
	dump->regs.esp = regs->sp;
	dump->regs.ss = regs->ss;

	#if 1 /* FIXME */
	dump->u_fpvalid = 0;
	#else
	dump->u_fpvalid = dump_fpu(regs, &dump->i387);
	#endif
	}

	#endif

	static struct linux_binfmt aout_format = {
	.module = THIS_MODULE,
	.load_binary = load_aout_binary,
	.load_shlib = load_aout_library,
	#ifdef CONFIG_COREDUMP
	.core_dump = aout_core_dump,
	#endif
	.min_coredump = PAGE_SIZE
	};

	static int set_brk(unsigned long start, unsigned long end)
	{
	start = PAGE_ALIGN(start);
	end = PAGE_ALIGN(end);
	if (end <= start)
	return 0;
	return vm_brk(start, end - start);
	}

	#ifdef CONFIG_COREDUMP
	/*
	* These are the only things you should do on a core-file: use only these
	* macros to write out all the necessary info.
	*/

	#include <linux/coredump.h>

	#define START_DATA(u) (u.u_tsize << PAGE_SHIFT)
	#define START_STACK(u) (u.start_stack)

	/*
	* Routine writes a core dump image in the current directory.
	* Currently only a stub-function.
	*
	* Note that setuid/setgid files won't make a core-dump if the uid/gid
	* changed due to the set[u\|g]id. It's enforced by the "current->mm->dumpable"
	* field, which also makes sure the core-dumps won't be recursive if the
	* dumping of the process results in another error..
	*/

	static int aout_core_dump(struct coredump_params *cprm)
	{
	mm_segment_t fs;
	int has_dumped = 0;
	unsigned long dump_start, dump_size;
	struct user32 dump;

	fs = get_fs();
	set_fs(KERNEL_DS);
	has_dumped = 1;
	strncpy(dump.u_comm, current->comm, sizeof(current->comm));
	dump.u_ar0 = offsetof(struct user32, regs);
	dump.signal = cprm->siginfo->si_signo;
	dump_thread32(cprm->regs, &dump);

	/*
	* If the size of the dump file exceeds the rlimit, then see
	* what would happen if we wrote the stack, but not the data
	* area.
	*/
	if ((dump.u_dsize + dump.u_ssize + 1) * PAGE_SIZE > cprm->limit)
	dump.u_dsize = 0;

	/* Make sure we have enough room to write the stack and data areas. */
	if ((dump.u_ssize + 1) * PAGE_SIZE > cprm->limit)
	dump.u_ssize = 0;

	/* make sure we actually have a data and stack area to dump */
	set_fs(USER_DS);
	if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_DATA(dump),
	dump.u_dsize << PAGE_SHIFT))
	dump.u_dsize = 0;
	if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_STACK(dump),
	dump.u_ssize << PAGE_SHIFT))
	dump.u_ssize = 0;

	set_fs(KERNEL_DS);
	/* struct user */
	if (!dump_emit(cprm, &dump, sizeof(dump)))
	goto end_coredump;
	/* Now dump all of the user data. Include malloced stuff as well */
	if (!dump_skip(cprm, PAGE_SIZE - sizeof(dump)))
	goto end_coredump;
	/* now we start writing out the user space info */
	set_fs(USER_DS);
	/* Dump the data area */
	if (dump.u_dsize != 0) {
	dump_start = START_DATA(dump);
	dump_size = dump.u_dsize << PAGE_SHIFT;
	if (!dump_emit(cprm, (void *)dump_start, dump_size))
	goto end_coredump;
	}
	/* Now prepare to dump the stack area */
	if (dump.u_ssize != 0) {
	dump_start = START_STACK(dump);
	dump_size = dump.u_ssize << PAGE_SHIFT;
	if (!dump_emit(cprm, (void *)dump_start, dump_size))
	goto end_coredump;
	}
	end_coredump:
	set_fs(fs);
	return has_dumped;
	}
	#endif

	/*
	* create_aout_tables() parses the env- and arg-strings in new user
	* memory and creates the pointer tables from them, and puts their
	* addresses on the "stack", returning the new stack pointer value.
	*/
	static u32 __user create_aout_tables(char __user p, struct linux_binprm *bprm)
	{
	u32 __user argv, envp, *sp;
	int argc = bprm->argc, envc = bprm->envc;

	sp = (u32 __user *) ((-(unsigned long)sizeof(u32)) & (unsigned long) p);
	sp -= envc+1;
	envp = sp;
	sp -= argc+1;
	argv = sp;
	put_user((unsigned long) envp, --sp);
	put_user((unsigned long) argv, --sp);
	put_user(argc, --sp);
	current->mm->arg_start = (unsigned long) p;
	while (argc-- > 0) {
	char c;

	put_user((u32)(unsigned long)p, argv++);
	do {
	get_user(c, p++);
	} while (c);
	}
	put_user(0, argv);
	current->mm->arg_end = current->mm->env_start = (unsigned long) p;
	while (envc-- > 0) {
	char c;

	put_user((u32)(unsigned long)p, envp++);
	do {
	get_user(c, p++);
	} while (c);
	}
	put_user(0, envp);
	current->mm->env_end = (unsigned long) p;
	return sp;
	}

	/*
	* These are the functions used to load a.out style executables and shared
	* libraries. There is no binary dependent code anywhere else.
	*/
	static int load_aout_binary(struct linux_binprm *bprm)
	{
	unsigned long error, fd_offset, rlim;
	struct pt_regs *regs = current_pt_regs();
	struct exec ex;
	int retval;

	ex = ((struct exec ) bprm->buf); /* exec-header */
	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
	N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) \|\|
	N_TRSIZE(ex) \|\| N_DRSIZE(ex) \|\|
	i_size_read(file_inode(bprm->file)) <
	ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
	return -ENOEXEC;
	}

	fd_offset = N_TXTOFF(ex);

	/* Check initial limits. This avoids letting people circumvent
	* size limits imposed on them by creating programs with large
	* arrays in the data or bss.
	*/
	rlim = rlimit(RLIMIT_DATA);
	if (rlim >= RLIM_INFINITY)
	rlim = ~0;
	if (ex.a_data + ex.a_bss > rlim)
	return -ENOMEM;

	/* Flush all traces of the currently running executable */
	retval = flush_old_exec(bprm);
	if (retval)
	return retval;

	/* OK, This is the point of no return */
	set_personality(PER_LINUX);
	set_personality_ia32(false);

	setup_new_exec(bprm);

	regs->cs = __USER32_CS;
	regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 =
	regs->r13 = regs->r14 = regs->r15 = 0;

	current->mm->end_code = ex.a_text +
	(current->mm->start_code = N_TXTADDR(ex));
	current->mm->end_data = ex.a_data +
	(current->mm->start_data = N_DATADDR(ex));
	current->mm->brk = ex.a_bss +
	(current->mm->start_brk = N_BSSADDR(ex));

	retval = setup_arg_pages(bprm, IA32_STACK_TOP, EXSTACK_DEFAULT);
	if (retval < 0)
	return retval;

	install_exec_creds(bprm);

	if (N_MAGIC(ex) == OMAGIC) {
	unsigned long text_addr, map_size;

	text_addr = N_TXTADDR(ex);
	map_size = ex.a_text+ex.a_data;

	error = vm_brk(text_addr & PAGE_MASK, map_size);

	if (error)
	return error;

	error = read_code(bprm->file, text_addr, 32,
	ex.a_text + ex.a_data);
	if ((signed long)error < 0)
	return error;
	} else {
	#ifdef WARN_OLD
	static unsigned long error_time, error_time2;
	if ((ex.a_text & 0xfff \|\| ex.a_data & 0xfff) &&
	(N_MAGIC(ex) != NMAGIC) &&
	time_after(jiffies, error_time2 + 5*HZ)) {
	printk(KERN_NOTICE "executable not page aligned\n");
	error_time2 = jiffies;
	}

	if ((fd_offset & ~PAGE_MASK) != 0 &&
	time_after(jiffies, error_time + 5*HZ)) {
	printk(KERN_WARNING
	"fd_offset is not page aligned. Please convert "
	"program: %pD\n",
	bprm->file);
	error_time = jiffies;
	}
	#endif

	if (!bprm->file->f_op->mmap \|\| (fd_offset & ~PAGE_MASK) != 0) {
	error = vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
	if (error)
	return error;

	read_code(bprm->file, N_TXTADDR(ex), fd_offset,
	ex.a_text+ex.a_data);
	goto beyond_if;
	}

	error = vm_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
	PROT_READ \| PROT_EXEC,
	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \|
	MAP_EXECUTABLE \| MAP_32BIT,
	fd_offset);

	if (error != N_TXTADDR(ex))
	return error;

	error = vm_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
	PROT_READ \| PROT_WRITE \| PROT_EXEC,
	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \|
	MAP_EXECUTABLE \| MAP_32BIT,
	fd_offset + ex.a_text);
	if (error != N_DATADDR(ex))
	return error;
	}

	beyond_if:
	error = set_brk(current->mm->start_brk, current->mm->brk);
	if (error)
	return error;

	set_binfmt(&aout_format);

	current->mm->start_stack =
	(unsigned long)create_aout_tables((char __user *)bprm->p, bprm);
	/* start thread */
	loadsegment(fs, 0);
	loadsegment(ds, __USER32_DS);
	loadsegment(es, __USER32_DS);
	load_gs_index(0);
	(regs)->ip = ex.a_entry;
	(regs)->sp = current->mm->start_stack;
	(regs)->flags = 0x200;
	(regs)->cs = __USER32_CS;
	(regs)->ss = __USER32_DS;
	regs->r8 = regs->r9 = regs->r10 = regs->r11 =
	regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
	set_fs(USER_DS);
	return 0;
	}

	static int load_aout_library(struct file *file)
	{
	unsigned long bss, start_addr, len, error;
	int retval;
	struct exec ex;


	retval = -ENOEXEC;
	error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
	if (error != sizeof(ex))
	goto out;

	/* We come in here for the regular a.out style of shared libraries */
	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) \|\| N_TRSIZE(ex) \|\|
	N_DRSIZE(ex) \|\| ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) \|\|
	i_size_read(file_inode(file)) <
	ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
	goto out;
	}

	if (N_FLAGS(ex))
	goto out;

	/* For QMAGIC, the starting address is 0x20 into the page. We mask
	this off to get the starting address for the page */

	start_addr = ex.a_entry & 0xfffff000;

	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
	#ifdef WARN_OLD
	static unsigned long error_time;
	if (time_after(jiffies, error_time + 5*HZ)) {
	printk(KERN_WARNING
	"N_TXTOFF is not page aligned. Please convert "
	"library: %pD\n",
	file);
	error_time = jiffies;
	}
	#endif
	retval = vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
	if (retval)
	goto out;

	read_code(file, start_addr, N_TXTOFF(ex),
	ex.a_text + ex.a_data);
	retval = 0;
	goto out;
	}
	/* Now use mmap to map the library into memory. */
	error = vm_mmap(file, start_addr, ex.a_text + ex.a_data,
	PROT_READ \| PROT_WRITE \| PROT_EXEC,
	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \| MAP_32BIT,
	N_TXTOFF(ex));
	retval = error;
	if (error != start_addr)
	goto out;

	len = PAGE_ALIGN(ex.a_text + ex.a_data);
	bss = ex.a_text + ex.a_data + ex.a_bss;
	if (bss > len) {
	retval = vm_brk(start_addr + len, bss - len);
	if (retval)
	goto out;
	}
	retval = 0;
	out:
	return retval;
	}

	static int __init init_aout_binfmt(void)
	{
	register_binfmt(&aout_format);
	return 0;
	}

	static void __exit exit_aout_binfmt(void)
	{
	unregister_binfmt(&aout_format);
	}

	module_init(init_aout_binfmt);
	module_exit(exit_aout_binfmt);
	MODULE_LICENSE("GPL");