[linux.git] / fs / binfmt_aout.c

/*
 *  linux/fs/binfmt_aout.c
 *
 *  Copyright (C) 1991, 1992, 1996  Linus Torvalds
 */

#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/coredump.h>
#include <linux/slab.h>

#include <asm/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/a.out-core.h>

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

#ifdef CONFIG_COREDUMP
/*
 * 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;
	void __user *dump_start;
	int dump_size;
	struct user dump;
#ifdef __alpha__
#       define START_DATA(u)	((void __user *)u.start_data)
#else
#	define START_DATA(u)	((void __user *)((u.u_tsize << PAGE_SHIFT) + \
				 u.start_code))
#endif
#       define START_STACK(u)   ((void __user *)u.start_stack)

	fs = get_fs();
	set_fs(KERNEL_DS);
	has_dumped = 1;
       	strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
	dump.u_ar0 = offsetof(struct user, regs);
	dump.signal = cprm->siginfo->si_signo;
	aout_dump_thread(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, START_DATA(dump), dump.u_dsize << PAGE_SHIFT))
		dump.u_dsize = 0;
	if (!access_ok(VERIFY_READ, 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, 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, dump_start, dump_size))
			goto end_coredump;
	}
end_coredump:
	set_fs(fs);
	return has_dumped;
}
#else
#define aout_core_dump NULL
#endif

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

#define BAD_ADDR(x)	((unsigned long)(x) >= TASK_SIZE)

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

/*
 * 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 unsigned long __user *create_aout_tables(char __user *p, struct linux_binprm * bprm)
{
	char __user * __user *argv;
	char __user * __user *envp;
	unsigned long __user *sp;
	int argc = bprm->argc;
	int envc = bprm->envc;

	sp = (void __user *)((-(unsigned long)sizeof(char *)) & (unsigned long) p);
#ifdef __alpha__
/* whee.. test-programs are so much fun. */
	put_user(0, --sp);
	put_user(0, --sp);
	if (bprm->loader) {
		put_user(0, --sp);
		put_user(1003, --sp);
		put_user(bprm->loader, --sp);
		put_user(1002, --sp);
	}
	put_user(bprm->exec, --sp);
	put_user(1001, --sp);
#endif
	sp -= envc+1;
	envp = (char __user * __user *) sp;
	sp -= argc+1;
	argv = (char __user * __user *) sp;
#ifndef __alpha__
	put_user((unsigned long) envp,--sp);
	put_user((unsigned long) argv,--sp);
#endif
	put_user(argc,--sp);
	current->mm->arg_start = (unsigned long) p;
	while (argc-->0) {
		char c;
		put_user(p,argv++);
		do {
			get_user(c,p++);
		} while (c);
	}
	put_user(NULL,argv);
	current->mm->arg_end = current->mm->env_start = (unsigned long) p;
	while (envc-->0) {
		char c;
		put_user(p,envp++);
		do {
			get_user(c,p++);
		} while (c);
	}
	put_user(NULL,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)
{
	struct pt_regs *regs = current_pt_regs();
	struct exec ex;
	unsigned long error;
	unsigned long fd_offset;
	unsigned long rlim;
	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;
	}

	/*
	 * Requires a mmap handler. This prevents people from using a.out
	 * as part of an exploit attack against /proc-related vulnerabilities.
	 */
	if (!bprm->file->f_op->mmap)
		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 */
#ifdef __alpha__
	SET_AOUT_PERSONALITY(bprm, ex);
#else
	set_personality(PER_LINUX);
#endif
	setup_new_exec(bprm);

	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, STACK_TOP, EXSTACK_DEFAULT);
	if (retval < 0)
		return retval;

	install_exec_creds(bprm);

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

		text_addr = N_TXTADDR(ex);

#ifdef __alpha__
		pos = fd_offset;
		map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1;
#else
		pos = 32;
		map_size = ex.a_text+ex.a_data;
#endif
		error = vm_brk(text_addr & PAGE_MASK, map_size);
		if (error)
			return error;

		error = read_code(bprm->file, text_addr, pos,
				  ex.a_text+ex.a_data);
		if ((signed long)error < 0)
			return error;
	} else {
		if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
		    (N_MAGIC(ex) != NMAGIC) && printk_ratelimit())
		{
			printk(KERN_NOTICE "executable not page aligned\n");
		}

		if ((fd_offset & ~PAGE_MASK) != 0 && printk_ratelimit())
		{
			printk(KERN_WARNING 
			       "fd_offset is not page aligned. Please convert program: %pD\n",
			       bprm->file);
		}

		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,
			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,
				fd_offset + ex.a_text);
		if (error != N_DATADDR(ex))
			return error;
	}
beyond_if:
	set_binfmt(&aout_format);

	retval = set_brk(current->mm->start_brk, current->mm->brk);
	if (retval < 0)
		return retval;

	current->mm->start_stack =
		(unsigned long) create_aout_tables((char __user *) bprm->p, bprm);
#ifdef __alpha__
	regs->gp = ex.a_gpvalue;
#endif
	start_thread(regs, ex.a_entry, current->mm->start_stack);
	return 0;
}

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

	inode = file_inode(file);

	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(inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
		goto out;
	}

	/*
	 * Requires a mmap handler. This prevents people from using a.out
	 * as part of an exploit attack against /proc-related vulnerabilities.
	 */
	if (!file->f_op->mmap)
		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) {
		if (printk_ratelimit())
		{
			printk(KERN_WARNING 
			       "N_TXTOFF is not page aligned. Please convert library: %pD\n",
			       file);
		}
		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,
			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);
}

core_initcall(init_aout_binfmt);
module_exit(exit_aout_binfmt);
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/binfmt_aout.c
	3	*
	4	* Copyright (C) 1991, 1992, 1996 Linus Torvalds
	5	*/
	6
	7	#include <linux/module.h>
	8
	9	#include <linux/time.h>
	10	#include <linux/kernel.h>
	11	#include <linux/mm.h>
	12	#include <linux/mman.h>
	13	#include <linux/a.out.h>
	14	#include <linux/errno.h>
	15	#include <linux/signal.h>
	16	#include <linux/string.h>
	17	#include <linux/fs.h>
	18	#include <linux/file.h>
	19	#include <linux/stat.h>
	20	#include <linux/fcntl.h>
	21	#include <linux/ptrace.h>
	22	#include <linux/user.h>
1da177e4 LT	23	#include <linux/binfmts.h>
	24	#include <linux/personality.h>
	25	#include <linux/init.h>
088e7af7	26	#include <linux/coredump.h>
5a0e3ad6	27	#include <linux/slab.h>
1da177e4	28
1da177e4 LT	29	#include <asm/uaccess.h>
1da177e4 LT	30	#include <asm/cacheflush.h>
7fa30315	31	#include <asm/a.out-core.h>
1da177e4	32
71613c3b	33	static int load_aout_binary(struct linux_binprm *);
1da177e4	34	static int load_aout_library(struct file*);
1da177e4	35
046d662f	36	#ifdef CONFIG_COREDUMP
1da177e4 LT	37	/*
	38	* Routine writes a core dump image in the current directory.
	39	* Currently only a stub-function.
	40	*
	41	* Note that setuid/setgid files won't make a core-dump if the uid/gid
	42	* changed due to the set[u\|g]id. It's enforced by the "current->mm->dumpable"
	43	* field, which also makes sure the core-dumps won't be recursive if the
	44	* dumping of the process results in another error..
	45	*/
f6151dfe	46	static int aout_core_dump(struct coredump_params *cprm)
1da177e4 LT	47	{
	48	mm_segment_t fs;
	49	int has_dumped = 0;
7731d9a5 BP	50	void __user *dump_start;
7731d9a5 BP	51	int dump_size;
1da177e4	52	struct user dump;
17580d7f	53	#ifdef __alpha__
7731d9a5	54	# define START_DATA(u) ((void __user *)u.start_data)
17580d7f	55	#else
7731d9a5 BP	56	# define START_DATA(u) ((void __user *)((u.u_tsize << PAGE_SHIFT) + \
7731d9a5 BP	57	u.start_code))
1da177e4	58	#endif
7731d9a5	59	# define START_STACK(u) ((void __user *)u.start_stack)
1da177e4 LT	60
	61	fs = get_fs();
	62	set_fs(KERNEL_DS);
	63	has_dumped = 1;
1da177e4	64	strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
6e16d89b	65	dump.u_ar0 = offsetof(struct user, regs);
5ab1c309	66	dump.signal = cprm->siginfo->si_signo;
f6151dfe	67	aout_dump_thread(cprm->regs, &dump);
1da177e4 LT	68
	69	/* If the size of the dump file exceeds the rlimit, then see what would happen
	70	if we wrote the stack, but not the data area. */
f6151dfe	71	if ((dump.u_dsize + dump.u_ssize+1) * PAGE_SIZE > cprm->limit)
1da177e4	72	dump.u_dsize = 0;
1da177e4 LT	73
1da177e4 LT	74	/* Make sure we have enough room to write the stack and data areas. */
f6151dfe	75	if ((dump.u_ssize + 1) * PAGE_SIZE > cprm->limit)
1da177e4	76	dump.u_ssize = 0;
1da177e4 LT	77
	78	/* make sure we actually have a data and stack area to dump */
	79	set_fs(USER_DS);
7731d9a5	80	if (!access_ok(VERIFY_READ, START_DATA(dump), dump.u_dsize << PAGE_SHIFT))
1da177e4	81	dump.u_dsize = 0;
7731d9a5	82	if (!access_ok(VERIFY_READ, START_STACK(dump), dump.u_ssize << PAGE_SHIFT))
1da177e4	83	dump.u_ssize = 0;
1da177e4 LT	84
	85	set_fs(KERNEL_DS);
	86	/* struct user */
43a5d548	87	if (!dump_emit(cprm, &dump, sizeof(dump)))
088e7af7	88	goto end_coredump;
1da177e4	89	/* Now dump all of the user data. Include malloced stuff as well */
9b56d543	90	if (!dump_skip(cprm, PAGE_SIZE - sizeof(dump)))
05f47fda	91	goto end_coredump;
1da177e4 LT	92	/* now we start writing out the user space info */
	93	set_fs(USER_DS);
	94	/* Dump the data area */
	95	if (dump.u_dsize != 0) {
	96	dump_start = START_DATA(dump);
1da177e4	97	dump_size = dump.u_dsize << PAGE_SHIFT;
43a5d548	98	if (!dump_emit(cprm, dump_start, dump_size))
088e7af7	99	goto end_coredump;
1da177e4 LT	100	}
	101	/* Now prepare to dump the stack area */
	102	if (dump.u_ssize != 0) {
	103	dump_start = START_STACK(dump);
1da177e4	104	dump_size = dump.u_ssize << PAGE_SHIFT;
43a5d548	105	if (!dump_emit(cprm, dump_start, dump_size))
088e7af7	106	goto end_coredump;
1da177e4	107	}
1da177e4 LT	108	end_coredump:
	109	set_fs(fs);
	110	return has_dumped;
	111	}
046d662f AK	112	#else
	113	#define aout_core_dump NULL
	114	#endif
	115
	116	static struct linux_binfmt aout_format = {
	117	.module = THIS_MODULE,
	118	.load_binary = load_aout_binary,
	119	.load_shlib = load_aout_library,
	120	.core_dump = aout_core_dump,
	121	.min_coredump = PAGE_SIZE
	122	};
	123
	124	#define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
	125
	126	static int set_brk(unsigned long start, unsigned long end)
	127	{
	128	start = PAGE_ALIGN(start);
	129	end = PAGE_ALIGN(end);
5d22fc25 LT	130	if (end > start)
5d22fc25 LT	131	return vm_brk(start, end - start);
046d662f AK	132	return 0;
046d662f AK	133	}
1da177e4 LT	134
	135	/*
	136	* create_aout_tables() parses the env- and arg-strings in new user
	137	* memory and creates the pointer tables from them, and puts their
	138	* addresses on the "stack", returning the new stack pointer value.
	139	*/
	140	static unsigned long __user create_aout_tables(char __user p, struct linux_binprm * bprm)
	141	{
	142	char __user * __user *argv;
	143	char __user * __user *envp;
	144	unsigned long __user *sp;
	145	int argc = bprm->argc;
	146	int envc = bprm->envc;
	147
	148	sp = (void __user )((-(unsigned long)sizeof(char )) & (unsigned long) p);
1da177e4 LT	149	#ifdef __alpha__
	150	/* whee.. test-programs are so much fun. */
	151	put_user(0, --sp);
	152	put_user(0, --sp);
	153	if (bprm->loader) {
	154	put_user(0, --sp);
17580d7f	155	put_user(1003, --sp);
1da177e4	156	put_user(bprm->loader, --sp);
17580d7f	157	put_user(1002, --sp);
1da177e4 LT	158	}
1da177e4 LT	159	put_user(bprm->exec, --sp);
17580d7f	160	put_user(1001, --sp);
1da177e4 LT	161	#endif
	162	sp -= envc+1;
	163	envp = (char __user * __user *) sp;
	164	sp -= argc+1;
	165	argv = (char __user * __user *) sp;
17580d7f	166	#ifndef __alpha__
1da177e4 LT	167	put_user((unsigned long) envp,--sp);
	168	put_user((unsigned long) argv,--sp);
	169	#endif
	170	put_user(argc,--sp);
	171	current->mm->arg_start = (unsigned long) p;
	172	while (argc-->0) {
	173	char c;
	174	put_user(p,argv++);
	175	do {
	176	get_user(c,p++);
	177	} while (c);
	178	}
	179	put_user(NULL,argv);
	180	current->mm->arg_end = current->mm->env_start = (unsigned long) p;
	181	while (envc-->0) {
	182	char c;
	183	put_user(p,envp++);
	184	do {
	185	get_user(c,p++);
	186	} while (c);
	187	}
	188	put_user(NULL,envp);
	189	current->mm->env_end = (unsigned long) p;
	190	return sp;
	191	}
	192
	193	/*
	194	* These are the functions used to load a.out style executables and shared
	195	* libraries. There is no binary dependent code anywhere else.
	196	*/
	197
71613c3b	198	static int load_aout_binary(struct linux_binprm * bprm)
1da177e4	199	{
71613c3b	200	struct pt_regs *regs = current_pt_regs();
1da177e4 LT	201	struct exec ex;
	202	unsigned long error;
	203	unsigned long fd_offset;
	204	unsigned long rlim;
	205	int retval;
	206
	207	ex = ((struct exec ) bprm->buf); /* exec-header */
	208	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
	209	N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) \|\|
	210	N_TRSIZE(ex) \|\| N_DRSIZE(ex) \|\|
496ad9aa	211	i_size_read(file_inode(bprm->file)) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
1da177e4 LT	212	return -ENOEXEC;
	213	}
	214
8454aeef ET	215	/*
	216	* Requires a mmap handler. This prevents people from using a.out
	217	* as part of an exploit attack against /proc-related vulnerabilities.
	218	*/
72c2d531	219	if (!bprm->file->f_op->mmap)
8454aeef ET	220	return -ENOEXEC;
8454aeef ET	221
1da177e4 LT	222	fd_offset = N_TXTOFF(ex);
	223
	224	/* Check initial limits. This avoids letting people circumvent
	225	* size limits imposed on them by creating programs with large
	226	* arrays in the data or bss.
	227	*/
d554ed89	228	rlim = rlimit(RLIMIT_DATA);
1da177e4 LT	229	if (rlim >= RLIM_INFINITY)
	230	rlim = ~0;
	231	if (ex.a_data + ex.a_bss > rlim)
	232	return -ENOMEM;
	233
	234	/* Flush all traces of the currently running executable */
	235	retval = flush_old_exec(bprm);
	236	if (retval)
	237	return retval;
	238
	239	/* OK, This is the point of no return */
17580d7f	240	#ifdef __alpha__
1da177e4	241	SET_AOUT_PERSONALITY(bprm, ex);
1da177e4 LT	242	#else
	243	set_personality(PER_LINUX);
	244	#endif
221af7f8	245	setup_new_exec(bprm);
1da177e4 LT	246
	247	current->mm->end_code = ex.a_text +
	248	(current->mm->start_code = N_TXTADDR(ex));
	249	current->mm->end_data = ex.a_data +
	250	(current->mm->start_data = N_DATADDR(ex));
	251	current->mm->brk = ex.a_bss +
	252	(current->mm->start_brk = N_BSSADDR(ex));
1da177e4	253
6414fa6a	254	retval = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
19d860a1	255	if (retval < 0)
6414fa6a	256	return retval;
6414fa6a	257
a6f76f23	258	install_exec_creds(bprm);
1da177e4 LT	259
	260	if (N_MAGIC(ex) == OMAGIC) {
	261	unsigned long text_addr, map_size;
	262	loff_t pos;
	263
	264	text_addr = N_TXTADDR(ex);
	265
fe30af97	266	#ifdef __alpha__
1da177e4 LT	267	pos = fd_offset;
	268	map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1;
	269	#else
	270	pos = 32;
	271	map_size = ex.a_text+ex.a_data;
	272	#endif
e4eb1ff6	273	error = vm_brk(text_addr & PAGE_MASK, map_size);
5d22fc25	274	if (error)
1da177e4	275	return error;
1da177e4	276
3dc20cb2 AV	277	error = read_code(bprm->file, text_addr, pos,
3dc20cb2 AV	278	ex.a_text+ex.a_data);
19d860a1	279	if ((signed long)error < 0)
1da177e4	280	return error;
1da177e4	281	} else {
1da177e4	282	if ((ex.a_text & 0xfff \|\| ex.a_data & 0xfff) &&
2e50b6cc	283	(N_MAGIC(ex) != NMAGIC) && printk_ratelimit())
1da177e4 LT	284	{
1da177e4 LT	285	printk(KERN_NOTICE "executable not page aligned\n");
1da177e4 LT	286	}
1da177e4 LT	287
2e50b6cc	288	if ((fd_offset & ~PAGE_MASK) != 0 && printk_ratelimit())
1da177e4 LT	289	{
1da177e4 LT	290	printk(KERN_WARNING
a455589f AV	291	"fd_offset is not page aligned. Please convert program: %pD\n",
a455589f AV	292	bprm->file);
1da177e4 LT	293	}
	294
	295	if (!bprm->file->f_op->mmap\|\|((fd_offset & ~PAGE_MASK) != 0)) {
864778b1	296	error = vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
5d22fc25	297	if (error)
864778b1 MH	298	return error;
864778b1 MH	299
3dc20cb2 AV	300	read_code(bprm->file, N_TXTADDR(ex), fd_offset,
3dc20cb2 AV	301	ex.a_text + ex.a_data);
1da177e4 LT	302	goto beyond_if;
	303	}
	304
6be5ceb0	305	error = vm_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
1da177e4 LT	306	PROT_READ \| PROT_EXEC,
	307	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \| MAP_EXECUTABLE,
	308	fd_offset);
1da177e4	309
19d860a1	310	if (error != N_TXTADDR(ex))
1da177e4	311	return error;
1da177e4	312
6be5ceb0	313	error = vm_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
1da177e4 LT	314	PROT_READ \| PROT_WRITE \| PROT_EXEC,
	315	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \| MAP_EXECUTABLE,
	316	fd_offset + ex.a_text);
19d860a1	317	if (error != N_DATADDR(ex))
1da177e4	318	return error;
1da177e4 LT	319	}
	320	beyond_if:
	321	set_binfmt(&aout_format);
	322
	323	retval = set_brk(current->mm->start_brk, current->mm->brk);
19d860a1	324	if (retval < 0)
1da177e4	325	return retval;
1da177e4	326
1da177e4 LT	327	current->mm->start_stack =
	328	(unsigned long) create_aout_tables((char __user *) bprm->p, bprm);
	329	#ifdef __alpha__
	330	regs->gp = ex.a_gpvalue;
	331	#endif
	332	start_thread(regs, ex.a_entry, current->mm->start_stack);
1da177e4 LT	333	return 0;
	334	}
	335
	336	static int load_aout_library(struct file *file)
	337	{
	338	struct inode * inode;
	339	unsigned long bss, start_addr, len;
	340	unsigned long error;
	341	int retval;
	342	struct exec ex;
	343
496ad9aa	344	inode = file_inode(file);
1da177e4 LT	345
	346	retval = -ENOEXEC;
	347	error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
	348	if (error != sizeof(ex))
	349	goto out;
	350
	351	/* We come in here for the regular a.out style of shared libraries */
	352	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) \|\| N_TRSIZE(ex) \|\|
	353	N_DRSIZE(ex) \|\| ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) \|\|
	354	i_size_read(inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
	355	goto out;
	356	}
	357
8454aeef ET	358	/*
	359	* Requires a mmap handler. This prevents people from using a.out
	360	* as part of an exploit attack against /proc-related vulnerabilities.
	361	*/
72c2d531	362	if (!file->f_op->mmap)
8454aeef ET	363	goto out;
8454aeef ET	364
1da177e4 LT	365	if (N_FLAGS(ex))
	366	goto out;
	367
	368	/* For QMAGIC, the starting address is 0x20 into the page. We mask
	369	this off to get the starting address for the page */
	370
	371	start_addr = ex.a_entry & 0xfffff000;
	372
	373	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
2e50b6cc	374	if (printk_ratelimit())
1da177e4 LT	375	{
1da177e4 LT	376	printk(KERN_WARNING
a455589f AV	377	"N_TXTOFF is not page aligned. Please convert library: %pD\n",
a455589f AV	378	file);
1da177e4	379	}
864778b1	380	retval = vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
5d22fc25	381	if (retval)
864778b1 MH	382	goto out;
864778b1 MH	383
3dc20cb2 AV	384	read_code(file, start_addr, N_TXTOFF(ex),
3dc20cb2 AV	385	ex.a_text + ex.a_data);
1da177e4 LT	386	retval = 0;
	387	goto out;
	388	}
	389	/* Now use mmap to map the library into memory. */
6be5ceb0	390	error = vm_mmap(file, start_addr, ex.a_text + ex.a_data,
1da177e4 LT	391	PROT_READ \| PROT_WRITE \| PROT_EXEC,
	392	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE,
	393	N_TXTOFF(ex));
1da177e4 LT	394	retval = error;
	395	if (error != start_addr)
	396	goto out;
	397
	398	len = PAGE_ALIGN(ex.a_text + ex.a_data);
	399	bss = ex.a_text + ex.a_data + ex.a_bss;
	400	if (bss > len) {
5d22fc25 LT	401	retval = vm_brk(start_addr + len, bss - len);
5d22fc25 LT	402	if (retval)
1da177e4 LT	403	goto out;
	404	}
	405	retval = 0;
	406	out:
	407	return retval;
	408	}
	409
	410	static int __init init_aout_binfmt(void)
	411	{
8fc3dc5a AV	412	register_binfmt(&aout_format);
8fc3dc5a AV	413	return 0;
1da177e4 LT	414	}
	415
	416	static void __exit exit_aout_binfmt(void)
	417	{
	418	unregister_binfmt(&aout_format);
	419	}
	420
	421	core_initcall(init_aout_binfmt);
	422	module_exit(exit_aout_binfmt);
	423	MODULE_LICENSE("GPL");