[net-next-2.6.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/slab.h>
#include <linux/binfmts.h>
#include <linux/personality.h>
#include <linux/init.h>

#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/cacheflush.h>

static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs);
static int load_aout_library(struct file*);
static int aout_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);

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) {
		unsigned long addr;
		down_write(&current->mm->mmap_sem);
		addr = do_brk(start, end - start);
		up_write(&current->mm->mmap_sem);
		if (BAD_ADDR(addr))
			return addr;
	}
	return 0;
}

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

static int dump_write(struct file *file, const void *addr, int nr)
{
	return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
}

#define DUMP_WRITE(addr, nr)	\
	if (!dump_write(file, (void *)(addr), (nr))) \
		goto end_coredump;

#define DUMP_SEEK(offset) \
if (file->f_op->llseek) { \
	if (file->f_op->llseek(file,(offset),0) != (offset)) \
 		goto end_coredump; \
} else file->f_pos = (offset)

/*
 * 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(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
{
	mm_segment_t fs;
	int has_dumped = 0;
	unsigned long dump_start, dump_size;
	struct user dump;
#if defined(__alpha__)
#       define START_DATA(u)	(u.start_data)
#elif defined(__arm__)
#	define START_DATA(u)	((u.u_tsize << PAGE_SHIFT) + u.start_code)
#elif defined(__sparc__)
#       define START_DATA(u)    (u.u_tsize)
#elif defined(__i386__) || defined(__mc68000__) || defined(__arch_um__)
#       define START_DATA(u)	(u.u_tsize << PAGE_SHIFT)
#endif
#ifdef __sparc__
#       define START_STACK(u)   ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))
#else
#       define START_STACK(u)   (u.start_stack)
#endif

	fs = get_fs();
	set_fs(KERNEL_DS);
	has_dumped = 1;
	current->flags |= PF_DUMPCORE;
       	strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
#ifndef __sparc__
	dump.u_ar0 = offsetof(struct user, regs);
#endif
	dump.signal = signr;
	dump_thread(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.  */
#ifdef __sparc__
	if ((dump.u_dsize + dump.u_ssize) > limit)
		dump.u_dsize = 0;
#else
	if ((dump.u_dsize + dump.u_ssize+1) * PAGE_SIZE > limit)
		dump.u_dsize = 0;
#endif

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

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

	set_fs(KERNEL_DS);
/* struct user */
	DUMP_WRITE(&dump,sizeof(dump));
/* Now dump all of the user data.  Include malloced stuff as well */
#ifndef __sparc__
	DUMP_SEEK(PAGE_SIZE);
#endif
/* 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);
#ifdef __sparc__
		dump_size = dump.u_dsize;
#else
		dump_size = dump.u_dsize << PAGE_SHIFT;
#endif
		DUMP_WRITE(dump_start,dump_size);
	}
/* Now prepare to dump the stack area */
	if (dump.u_ssize != 0) {
		dump_start = START_STACK(dump);
#ifdef __sparc__
		dump_size = dump.u_ssize;
#else
		dump_size = dump.u_ssize << PAGE_SHIFT;
#endif
		DUMP_WRITE(dump_start,dump_size);
	}
/* Finally dump the task struct.  Not be used by gdb, but could be useful */
	set_fs(KERNEL_DS);
	DUMP_WRITE(current,sizeof(*current));
end_coredump:
	set_fs(fs);
	return has_dumped;
}

/*
 * 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 __sparc__
	/* This imposes the proper stack alignment for a new process. */
	sp = (void __user *) (((unsigned long) sp) & ~7);
	if ((envc+argc+3)&1) --sp;
#endif
#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(0x3eb, --sp);
		put_user(bprm->loader, --sp);
		put_user(0x3ea, --sp);
	}
	put_user(bprm->exec, --sp);
	put_user(0x3e9, --sp);
#endif
	sp -= envc+1;
	envp = (char __user * __user *) sp;
	sp -= argc+1;
	argv = (char __user * __user *) sp;
#if defined(__i386__) || defined(__mc68000__) || defined(__arm__) || defined(__arch_um__)
	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)
{
	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(bprm->file->f_path.dentry->d_inode) < 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 || !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 = current->signal->rlim[RLIMIT_DATA].rlim_cur;
	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 */
#if defined(__alpha__)
	SET_AOUT_PERSONALITY(bprm, ex);
#elif defined(__sparc__)
	set_personality(PER_SUNOS);
#if !defined(__sparc_v9__)
	memcpy(&current->thread.core_exec, &ex, sizeof(struct exec));
#endif
#else
	set_personality(PER_LINUX);
#endif

	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));
	current->mm->free_area_cache = current->mm->mmap_base;
	current->mm->cached_hole_size = 0;

	compute_creds(bprm);
 	current->flags &= ~PF_FORKNOEXEC;
#ifdef __sparc__
	if (N_MAGIC(ex) == NMAGIC) {
		loff_t pos = fd_offset;
		/* Fuck me plenty... */
		/* <AOL></AOL> */
		down_write(&current->mm->mmap_sem);	
		error = do_brk(N_TXTADDR(ex), ex.a_text);
		up_write(&current->mm->mmap_sem);
		bprm->file->f_op->read(bprm->file, (char *) N_TXTADDR(ex),
			  ex.a_text, &pos);
		down_write(&current->mm->mmap_sem);
		error = do_brk(N_DATADDR(ex), ex.a_data);
		up_write(&current->mm->mmap_sem);
		bprm->file->f_op->read(bprm->file, (char *) N_DATADDR(ex),
			  ex.a_data, &pos);
		goto beyond_if;
	}
#endif

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

		text_addr = N_TXTADDR(ex);

#if defined(__alpha__) || defined(__sparc__)
		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
		down_write(&current->mm->mmap_sem);
		error = do_brk(text_addr & PAGE_MASK, map_size);
		up_write(&current->mm->mmap_sem);
		if (error != (text_addr & PAGE_MASK)) {
			send_sig(SIGKILL, current, 0);
			return error;
		}

		error = bprm->file->f_op->read(bprm->file,
			  (char __user *)text_addr,
			  ex.a_text+ex.a_data, &pos);
		if ((signed long)error < 0) {
			send_sig(SIGKILL, current, 0);
			return error;
		}
			 
		flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
	} else {
		static unsigned long error_time, error_time2;
		if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
		    (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ)
		{
			printk(KERN_NOTICE "executable not page aligned\n");
			error_time2 = jiffies;
		}

		if ((fd_offset & ~PAGE_MASK) != 0 &&
		    (jiffies-error_time) > 5*HZ)
		{
			printk(KERN_WARNING 
			       "fd_offset is not page aligned. Please convert program: %s\n",
			       bprm->file->f_path.dentry->d_name.name);
			error_time = jiffies;
		}

		if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
			loff_t pos = fd_offset;
			down_write(&current->mm->mmap_sem);
			do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
			up_write(&current->mm->mmap_sem);
			bprm->file->f_op->read(bprm->file,
					(char __user *)N_TXTADDR(ex),
					ex.a_text+ex.a_data, &pos);
			flush_icache_range((unsigned long) N_TXTADDR(ex),
					   (unsigned long) N_TXTADDR(ex) +
					   ex.a_text+ex.a_data);
			goto beyond_if;
		}

		down_write(&current->mm->mmap_sem);
		error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
			PROT_READ | PROT_EXEC,
			MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
			fd_offset);
		up_write(&current->mm->mmap_sem);

		if (error != N_TXTADDR(ex)) {
			send_sig(SIGKILL, current, 0);
			return error;
		}

		down_write(&current->mm->mmap_sem);
 		error = do_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);
		up_write(&current->mm->mmap_sem);
		if (error != N_DATADDR(ex)) {
			send_sig(SIGKILL, current, 0);
			return error;
		}
	}
beyond_if:
	set_binfmt(&aout_format);

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

	retval = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
	if (retval < 0) { 
		/* Someone check-me: is this error path enough? */ 
		send_sig(SIGKILL, current, 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);
	if (unlikely(current->ptrace & PT_PTRACED)) {
		if (current->ptrace & PT_TRACE_EXEC)
			ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP);
		else
			send_sig(SIGTRAP, current, 0);
	}
	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->f_path.dentry->d_inode;

	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 || !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) {
		static unsigned long error_time;
		loff_t pos = N_TXTOFF(ex);

		if ((jiffies-error_time) > 5*HZ)
		{
			printk(KERN_WARNING 
			       "N_TXTOFF is not page aligned. Please convert library: %s\n",
			       file->f_path.dentry->d_name.name);
			error_time = jiffies;
		}
		down_write(&current->mm->mmap_sem);
		do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
		up_write(&current->mm->mmap_sem);
		
		file->f_op->read(file, (char __user *)start_addr,
			ex.a_text + ex.a_data, &pos);
		flush_icache_range((unsigned long) start_addr,
				   (unsigned long) start_addr + ex.a_text + ex.a_data);

		retval = 0;
		goto out;
	}
	/* Now use mmap to map the library into memory. */
	down_write(&current->mm->mmap_sem);
	error = do_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));
	up_write(&current->mm->mmap_sem);
	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) {
		down_write(&current->mm->mmap_sem);
		error = do_brk(start_addr + len, bss - len);
		up_write(&current->mm->mmap_sem);
		retval = error;
		if (error != start_addr + len)
			goto out;
	}
	retval = 0;
out:
	return retval;
}

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

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>
	23	#include <linux/slab.h>
	24	#include <linux/binfmts.h>
	25	#include <linux/personality.h>
	26	#include <linux/init.h>
	27
	28	#include <asm/system.h>
	29	#include <asm/uaccess.h>
	30	#include <asm/cacheflush.h>
	31
	32	static int load_aout_binary(struct linux_binprm , struct pt_regs regs);
	33	static int load_aout_library(struct file*);
7dc0b22e	34	static int aout_core_dump(long signr, struct pt_regs regs, struct file file, unsigned long limit);
1da177e4	35
1da177e4 LT	36	static struct linux_binfmt aout_format = {
	37	.module = THIS_MODULE,
	38	.load_binary = load_aout_binary,
	39	.load_shlib = load_aout_library,
	40	.core_dump = aout_core_dump,
	41	.min_coredump = PAGE_SIZE
	42	};
	43
	44	#define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
	45
	46	static int set_brk(unsigned long start, unsigned long end)
	47	{
	48	start = PAGE_ALIGN(start);
	49	end = PAGE_ALIGN(end);
	50	if (end > start) {
	51	unsigned long addr;
	52	down_write(&current->mm->mmap_sem);
	53	addr = do_brk(start, end - start);
	54	up_write(&current->mm->mmap_sem);
	55	if (BAD_ADDR(addr))
	56	return addr;
	57	}
	58	return 0;
	59	}
	60
	61	/*
	62	* These are the only things you should do on a core-file: use only these
	63	* macros to write out all the necessary info.
	64	*/
	65
	66	static int dump_write(struct file file, const void addr, int nr)
	67	{
	68	return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
	69	}
	70
	71	#define DUMP_WRITE(addr, nr) \
	72	if (!dump_write(file, (void *)(addr), (nr))) \
	73	goto end_coredump;
	74
	75	#define DUMP_SEEK(offset) \
	76	if (file->f_op->llseek) { \
	77	if (file->f_op->llseek(file,(offset),0) != (offset)) \
	78	goto end_coredump; \
	79	} else file->f_pos = (offset)
	80
	81	/*
	82	* Routine writes a core dump image in the current directory.
	83	* Currently only a stub-function.
	84	*
	85	* Note that setuid/setgid files won't make a core-dump if the uid/gid
	86	* changed due to the set[u\|g]id. It's enforced by the "current->mm->dumpable"
	87	* field, which also makes sure the core-dumps won't be recursive if the
	88	* dumping of the process results in another error..
	89	*/
	90
7dc0b22e	91	static int aout_core_dump(long signr, struct pt_regs regs, struct file file, unsigned long limit)
1da177e4 LT	92	{
	93	mm_segment_t fs;
	94	int has_dumped = 0;
	95	unsigned long dump_start, dump_size;
	96	struct user dump;
	97	#if defined(__alpha__)
	98	# define START_DATA(u) (u.start_data)
	99	#elif defined(__arm__)
	100	# define START_DATA(u) ((u.u_tsize << PAGE_SHIFT) + u.start_code)
	101	#elif defined(__sparc__)
	102	# define START_DATA(u) (u.u_tsize)
	103	#elif defined(__i386__) \|\| defined(__mc68000__) \|\| defined(__arch_um__)
	104	# define START_DATA(u) (u.u_tsize << PAGE_SHIFT)
	105	#endif
	106	#ifdef __sparc__
	107	# define START_STACK(u) ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))
	108	#else
	109	# define START_STACK(u) (u.start_stack)
	110	#endif
	111
	112	fs = get_fs();
	113	set_fs(KERNEL_DS);
	114	has_dumped = 1;
	115	current->flags \|= PF_DUMPCORE;
	116	strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
	117	#ifndef __sparc__
6e16d89b	118	dump.u_ar0 = offsetof(struct user, regs);
1da177e4 LT	119	#endif
	120	dump.signal = signr;
	121	dump_thread(regs, &dump);
	122
	123	/* If the size of the dump file exceeds the rlimit, then see what would happen
	124	if we wrote the stack, but not the data area. */
	125	#ifdef __sparc__
7dc0b22e	126	if ((dump.u_dsize + dump.u_ssize) > limit)
1da177e4 LT	127	dump.u_dsize = 0;
1da177e4 LT	128	#else
7dc0b22e	129	if ((dump.u_dsize + dump.u_ssize+1) * PAGE_SIZE > limit)
1da177e4 LT	130	dump.u_dsize = 0;
	131	#endif
	132
	133	/* Make sure we have enough room to write the stack and data areas. */
	134	#ifdef __sparc__
7dc0b22e	135	if (dump.u_ssize > limit)
1da177e4 LT	136	dump.u_ssize = 0;
1da177e4 LT	137	#else
7dc0b22e	138	if ((dump.u_ssize + 1) * PAGE_SIZE > limit)
1da177e4 LT	139	dump.u_ssize = 0;
	140	#endif
	141
	142	/* make sure we actually have a data and stack area to dump */
	143	set_fs(USER_DS);
	144	#ifdef __sparc__
	145	if (!access_ok(VERIFY_READ, (void __user *)START_DATA(dump), dump.u_dsize))
	146	dump.u_dsize = 0;
	147	if (!access_ok(VERIFY_READ, (void __user *)START_STACK(dump), dump.u_ssize))
	148	dump.u_ssize = 0;
	149	#else
	150	if (!access_ok(VERIFY_READ, (void __user *)START_DATA(dump), dump.u_dsize << PAGE_SHIFT))
	151	dump.u_dsize = 0;
	152	if (!access_ok(VERIFY_READ, (void __user *)START_STACK(dump), dump.u_ssize << PAGE_SHIFT))
	153	dump.u_ssize = 0;
	154	#endif
	155
	156	set_fs(KERNEL_DS);
	157	/* struct user */
	158	DUMP_WRITE(&dump,sizeof(dump));
	159	/* Now dump all of the user data. Include malloced stuff as well */
	160	#ifndef __sparc__
	161	DUMP_SEEK(PAGE_SIZE);
	162	#endif
	163	/* now we start writing out the user space info */
	164	set_fs(USER_DS);
	165	/* Dump the data area */
	166	if (dump.u_dsize != 0) {
	167	dump_start = START_DATA(dump);
	168	#ifdef __sparc__
	169	dump_size = dump.u_dsize;
	170	#else
	171	dump_size = dump.u_dsize << PAGE_SHIFT;
	172	#endif
	173	DUMP_WRITE(dump_start,dump_size);
	174	}
	175	/* Now prepare to dump the stack area */
	176	if (dump.u_ssize != 0) {
	177	dump_start = START_STACK(dump);
	178	#ifdef __sparc__
	179	dump_size = dump.u_ssize;
	180	#else
	181	dump_size = dump.u_ssize << PAGE_SHIFT;
	182	#endif
	183	DUMP_WRITE(dump_start,dump_size);
	184	}
	185	/* Finally dump the task struct. Not be used by gdb, but could be useful */
	186	set_fs(KERNEL_DS);
	187	DUMP_WRITE(current,sizeof(*current));
	188	end_coredump:
	189	set_fs(fs);
	190	return has_dumped;
	191	}
	192
	193	/*
	194	* create_aout_tables() parses the env- and arg-strings in new user
	195	* memory and creates the pointer tables from them, and puts their
	196	* addresses on the "stack", returning the new stack pointer value.
	197	*/
	198	static unsigned long __user create_aout_tables(char __user p, struct linux_binprm * bprm)
	199	{
	200	char __user * __user *argv;
	201	char __user * __user *envp;
	202	unsigned long __user *sp;
203	int argc = bprm->argc;
204	int envc = bprm->envc;
205
206	sp = (void __user )((-(unsigned long)sizeof(char )) & (unsigned long) p);
207	#ifdef __sparc__
208	/* This imposes the proper stack alignment for a new process. */
209	sp = (void __user *) (((unsigned long) sp) & ~7);
210	if ((envc+argc+3)&1) --sp;
211	#endif
212	#ifdef __alpha__
213	/* whee.. test-programs are so much fun. */
214	put_user(0, --sp);
215	put_user(0, --sp);
216	if (bprm->loader) {
217	put_user(0, --sp);
218	put_user(0x3eb, --sp);
219	put_user(bprm->loader, --sp);
220	put_user(0x3ea, --sp);
221	}
222	put_user(bprm->exec, --sp);
223	put_user(0x3e9, --sp);
224	#endif
225	sp -= envc+1;
226	envp = (char __user * __user *) sp;
227	sp -= argc+1;
228	argv = (char __user * __user *) sp;
229	#if defined(__i386__) \|\| defined(__mc68000__) \|\| defined(__arm__) \|\| defined(__arch_um__)
230	put_user((unsigned long) envp,--sp);
231	put_user((unsigned long) argv,--sp);
232	#endif
233	put_user(argc,--sp);
234	current->mm->arg_start = (unsigned long) p;
235	while (argc-->0) {
236	char c;
237	put_user(p,argv++);
238	do {
239	get_user(c,p++);
240	} while (c);
241	}
242	put_user(NULL,argv);
243	current->mm->arg_end = current->mm->env_start = (unsigned long) p;
244	while (envc-->0) {
245	char c;
246	put_user(p,envp++);
247	do {
248	get_user(c,p++);
249	} while (c);
250	}
251	put_user(NULL,envp);
252	current->mm->env_end = (unsigned long) p;
253	return sp;
254	}
255
256	/*
257	* These are the functions used to load a.out style executables and shared
258	* libraries. There is no binary dependent code anywhere else.
259	*/
260
261	static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)
262	{
263	struct exec ex;
264	unsigned long error;
265	unsigned long fd_offset;
266	unsigned long rlim;
267	int retval;
268
269	ex = ((struct exec ) bprm->buf); /* exec-header */
270	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
271	N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) \|\|
272	N_TRSIZE(ex) \|\| N_DRSIZE(ex) \|\|
0f7fc9e4	273	i_size_read(bprm->file->f_path.dentry->d_inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
1da177e4 LT	274	return -ENOEXEC;
	275	}
	276
8454aeef ET	277	/*
	278	* Requires a mmap handler. This prevents people from using a.out
	279	* as part of an exploit attack against /proc-related vulnerabilities.
	280	*/
	281	if (!bprm->file->f_op \|\| !bprm->file->f_op->mmap)
	282	return -ENOEXEC;
	283
1da177e4 LT	284	fd_offset = N_TXTOFF(ex);
	285
	286	/* Check initial limits. This avoids letting people circumvent
	287	* size limits imposed on them by creating programs with large
	288	* arrays in the data or bss.
	289	*/
	290	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
	291	if (rlim >= RLIM_INFINITY)
	292	rlim = ~0;
	293	if (ex.a_data + ex.a_bss > rlim)
	294	return -ENOMEM;
	295
	296	/* Flush all traces of the currently running executable */
	297	retval = flush_old_exec(bprm);
	298	if (retval)
	299	return retval;
	300
	301	/* OK, This is the point of no return */
	302	#if defined(__alpha__)
	303	SET_AOUT_PERSONALITY(bprm, ex);
	304	#elif defined(__sparc__)
	305	set_personality(PER_SUNOS);
	306	#if !defined(__sparc_v9__)
	307	memcpy(&current->thread.core_exec, &ex, sizeof(struct exec));
	308	#endif
	309	#else
	310	set_personality(PER_LINUX);
	311	#endif
	312
	313	current->mm->end_code = ex.a_text +
	314	(current->mm->start_code = N_TXTADDR(ex));
	315	current->mm->end_data = ex.a_data +
	316	(current->mm->start_data = N_DATADDR(ex));
	317	current->mm->brk = ex.a_bss +
	318	(current->mm->start_brk = N_BSSADDR(ex));
	319	current->mm->free_area_cache = current->mm->mmap_base;
1363c3cd	320	current->mm->cached_hole_size = 0;
1da177e4	321
1da177e4 LT	322	compute_creds(bprm);
	323	current->flags &= ~PF_FORKNOEXEC;
	324	#ifdef __sparc__
	325	if (N_MAGIC(ex) == NMAGIC) {
	326	loff_t pos = fd_offset;
	327	/* Fuck me plenty... */
	328	/* <AOL></AOL> */
	329	down_write(&current->mm->mmap_sem);
	330	error = do_brk(N_TXTADDR(ex), ex.a_text);
	331	up_write(&current->mm->mmap_sem);
	332	bprm->file->f_op->read(bprm->file, (char *) N_TXTADDR(ex),
	333	ex.a_text, &pos);
	334	down_write(&current->mm->mmap_sem);
	335	error = do_brk(N_DATADDR(ex), ex.a_data);
	336	up_write(&current->mm->mmap_sem);
	337	bprm->file->f_op->read(bprm->file, (char *) N_DATADDR(ex),
	338	ex.a_data, &pos);
	339	goto beyond_if;
	340	}
	341	#endif
	342
	343	if (N_MAGIC(ex) == OMAGIC) {
	344	unsigned long text_addr, map_size;
	345	loff_t pos;
	346
	347	text_addr = N_TXTADDR(ex);
	348
	349	#if defined(__alpha__) \|\| defined(__sparc__)
	350	pos = fd_offset;
	351	map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1;
	352	#else
	353	pos = 32;
	354	map_size = ex.a_text+ex.a_data;
	355	#endif
	356	down_write(&current->mm->mmap_sem);
	357	error = do_brk(text_addr & PAGE_MASK, map_size);
	358	up_write(&current->mm->mmap_sem);
	359	if (error != (text_addr & PAGE_MASK)) {
	360	send_sig(SIGKILL, current, 0);
	361	return error;
	362	}
	363
	364	error = bprm->file->f_op->read(bprm->file,
	365	(char __user *)text_addr,
	366	ex.a_text+ex.a_data, &pos);
	367	if ((signed long)error < 0) {
	368	send_sig(SIGKILL, current, 0);
	369	return error;
	370	}
	371
	372	flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
	373	} else {
	374	static unsigned long error_time, error_time2;
	375	if ((ex.a_text & 0xfff \|\| ex.a_data & 0xfff) &&
	376	(N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ)
	377	{
	378	printk(KERN_NOTICE "executable not page aligned\n");
	379	error_time2 = jiffies;
	380	}
	381
	382	if ((fd_offset & ~PAGE_MASK) != 0 &&
	383	(jiffies-error_time) > 5*HZ)
	384	{
	385	printk(KERN_WARNING
386	"fd_offset is not page aligned. Please convert program: %s\n",
0f7fc9e4	387	bprm->file->f_path.dentry->d_name.name);
1da177e4 LT	388	error_time = jiffies;
	389	}
	390
	391	if (!bprm->file->f_op->mmap\|\|((fd_offset & ~PAGE_MASK) != 0)) {
	392	loff_t pos = fd_offset;
	393	down_write(&current->mm->mmap_sem);
	394	do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
	395	up_write(&current->mm->mmap_sem);
	396	bprm->file->f_op->read(bprm->file,
	397	(char __user *)N_TXTADDR(ex),
	398	ex.a_text+ex.a_data, &pos);
	399	flush_icache_range((unsigned long) N_TXTADDR(ex),
	400	(unsigned long) N_TXTADDR(ex) +
	401	ex.a_text+ex.a_data);
	402	goto beyond_if;
	403	}
	404
	405	down_write(&current->mm->mmap_sem);
	406	error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
	407	PROT_READ \| PROT_EXEC,
	408	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \| MAP_EXECUTABLE,
	409	fd_offset);
	410	up_write(&current->mm->mmap_sem);
	411
	412	if (error != N_TXTADDR(ex)) {
	413	send_sig(SIGKILL, current, 0);
	414	return error;
	415	}
	416
	417	down_write(&current->mm->mmap_sem);
	418	error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
	419	PROT_READ \| PROT_WRITE \| PROT_EXEC,
	420	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \| MAP_EXECUTABLE,
	421	fd_offset + ex.a_text);
	422	up_write(&current->mm->mmap_sem);
	423	if (error != N_DATADDR(ex)) {
	424	send_sig(SIGKILL, current, 0);
	425	return error;
	426	}
	427	}
	428	beyond_if:
	429	set_binfmt(&aout_format);
	430
	431	retval = set_brk(current->mm->start_brk, current->mm->brk);
	432	if (retval < 0) {
	433	send_sig(SIGKILL, current, 0);
	434	return retval;
	435	}
	436
	437	retval = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
	438	if (retval < 0) {
	439	/* Someone check-me: is this error path enough? */
	440	send_sig(SIGKILL, current, 0);
	441	return retval;
	442	}
	443
	444	current->mm->start_stack =
	445	(unsigned long) create_aout_tables((char __user *) bprm->p, bprm);
	446	#ifdef __alpha__
	447	regs->gp = ex.a_gpvalue;
	448	#endif
	449	start_thread(regs, ex.a_entry, current->mm->start_stack);
	450	if (unlikely(current->ptrace & PT_PTRACED)) {
	451	if (current->ptrace & PT_TRACE_EXEC)
452	ptrace_notify ((PTRACE_EVENT_EXEC << 8) \| SIGTRAP);
453	else
454	send_sig(SIGTRAP, current, 0);
455	}
456	return 0;
457	}
458
459	static int load_aout_library(struct file *file)
460	{
461	struct inode * inode;
462	unsigned long bss, start_addr, len;
463	unsigned long error;
464	int retval;
465	struct exec ex;
466
0f7fc9e4	467	inode = file->f_path.dentry->d_inode;
1da177e4 LT	468
	469	retval = -ENOEXEC;
	470	error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
	471	if (error != sizeof(ex))
	472	goto out;
	473
	474	/* We come in here for the regular a.out style of shared libraries */
	475	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) \|\| N_TRSIZE(ex) \|\|
	476	N_DRSIZE(ex) \|\| ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) \|\|
	477	i_size_read(inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
	478	goto out;
	479	}
	480
8454aeef ET	481	/*
	482	* Requires a mmap handler. This prevents people from using a.out
	483	* as part of an exploit attack against /proc-related vulnerabilities.
	484	*/
	485	if (!file->f_op \|\| !file->f_op->mmap)
	486	goto out;
	487
1da177e4 LT	488	if (N_FLAGS(ex))
	489	goto out;
	490
	491	/* For QMAGIC, the starting address is 0x20 into the page. We mask
	492	this off to get the starting address for the page */
	493
	494	start_addr = ex.a_entry & 0xfffff000;
	495
	496	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
	497	static unsigned long error_time;
	498	loff_t pos = N_TXTOFF(ex);
	499
	500	if ((jiffies-error_time) > 5*HZ)
	501	{
	502	printk(KERN_WARNING
	503	"N_TXTOFF is not page aligned. Please convert library: %s\n",
0f7fc9e4	504	file->f_path.dentry->d_name.name);
1da177e4 LT	505	error_time = jiffies;
	506	}
	507	down_write(&current->mm->mmap_sem);
	508	do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
	509	up_write(&current->mm->mmap_sem);
	510
	511	file->f_op->read(file, (char __user *)start_addr,
	512	ex.a_text + ex.a_data, &pos);
	513	flush_icache_range((unsigned long) start_addr,
	514	(unsigned long) start_addr + ex.a_text + ex.a_data);
	515
	516	retval = 0;
	517	goto out;
	518	}
	519	/* Now use mmap to map the library into memory. */
	520	down_write(&current->mm->mmap_sem);
	521	error = do_mmap(file, start_addr, ex.a_text + ex.a_data,
	522	PROT_READ \| PROT_WRITE \| PROT_EXEC,
	523	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE,
	524	N_TXTOFF(ex));
	525	up_write(&current->mm->mmap_sem);
	526	retval = error;
	527	if (error != start_addr)
	528	goto out;
	529
	530	len = PAGE_ALIGN(ex.a_text + ex.a_data);
	531	bss = ex.a_text + ex.a_data + ex.a_bss;
	532	if (bss > len) {
	533	down_write(&current->mm->mmap_sem);
	534	error = do_brk(start_addr + len, bss - len);
	535	up_write(&current->mm->mmap_sem);
	536	retval = error;
	537	if (error != start_addr + len)
	538	goto out;
	539	}
	540	retval = 0;
	541	out:
	542	return retval;
	543	}
	544
	545	static int __init init_aout_binfmt(void)
	546	{
	547	return register_binfmt(&aout_format);
	548	}
	549
	550	static void __exit exit_aout_binfmt(void)
	551	{
	552	unregister_binfmt(&aout_format);
	553	}
	554
	555	core_initcall(init_aout_binfmt);
	556	module_exit(exit_aout_binfmt);
	557	MODULE_LICENSE("GPL");