[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/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 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump)));
#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;

	current->mm->mmap = NULL;
	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__
	118	dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump)));
	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	current->mm->mmap = NULL;
	323	compute_creds(bprm);
	324	current->flags &= ~PF_FORKNOEXEC;
	325	#ifdef __sparc__
	326	if (N_MAGIC(ex) == NMAGIC) {
	327	loff_t pos = fd_offset;
	328	/* Fuck me plenty... */
	329	/* <AOL></AOL> */
	330	down_write(&current->mm->mmap_sem);
	331	error = do_brk(N_TXTADDR(ex), ex.a_text);
	332	up_write(&current->mm->mmap_sem);
	333	bprm->file->f_op->read(bprm->file, (char *) N_TXTADDR(ex),
	334	ex.a_text, &pos);
	335	down_write(&current->mm->mmap_sem);
	336	error = do_brk(N_DATADDR(ex), ex.a_data);
	337	up_write(&current->mm->mmap_sem);
	338	bprm->file->f_op->read(bprm->file, (char *) N_DATADDR(ex),
	339	ex.a_data, &pos);
	340	goto beyond_if;
	341	}
	342	#endif
	343
	344	if (N_MAGIC(ex) == OMAGIC) {
	345	unsigned long text_addr, map_size;
	346	loff_t pos;
	347
	348	text_addr = N_TXTADDR(ex);
	349
	350	#if defined(__alpha__) \|\| defined(__sparc__)
	351	pos = fd_offset;
	352	map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1;
	353	#else
	354	pos = 32;
	355	map_size = ex.a_text+ex.a_data;
	356	#endif
	357	down_write(&current->mm->mmap_sem);
	358	error = do_brk(text_addr & PAGE_MASK, map_size);
	359	up_write(&current->mm->mmap_sem);
	360	if (error != (text_addr & PAGE_MASK)) {
	361	send_sig(SIGKILL, current, 0);
	362	return error;
	363	}
	364
	365	error = bprm->file->f_op->read(bprm->file,
	366	(char __user *)text_addr,
	367	ex.a_text+ex.a_data, &pos);
	368	if ((signed long)error < 0) {
	369	send_sig(SIGKILL, current, 0);
	370	return error;
	371	}
	372
	373	flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
	374	} else {
	375	static unsigned long error_time, error_time2;
	376	if ((ex.a_text & 0xfff \|\| ex.a_data & 0xfff) &&
	377	(N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ)
	378	{
	379	printk(KERN_NOTICE "executable not page aligned\n");
	380	error_time2 = jiffies;
	381	}
	382
	383	if ((fd_offset & ~PAGE_MASK) != 0 &&
	384	(jiffies-error_time) > 5*HZ)
	385	{
386	printk(KERN_WARNING
387	"fd_offset is not page aligned. Please convert program: %s\n",
0f7fc9e4	388	bprm->file->f_path.dentry->d_name.name);
1da177e4 LT	389	error_time = jiffies;
	390	}
	391
	392	if (!bprm->file->f_op->mmap\|\|((fd_offset & ~PAGE_MASK) != 0)) {
	393	loff_t pos = fd_offset;
	394	down_write(&current->mm->mmap_sem);
	395	do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
	396	up_write(&current->mm->mmap_sem);
	397	bprm->file->f_op->read(bprm->file,
	398	(char __user *)N_TXTADDR(ex),
	399	ex.a_text+ex.a_data, &pos);
	400	flush_icache_range((unsigned long) N_TXTADDR(ex),
	401	(unsigned long) N_TXTADDR(ex) +
	402	ex.a_text+ex.a_data);
	403	goto beyond_if;
	404	}
	405
	406	down_write(&current->mm->mmap_sem);
	407	error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
	408	PROT_READ \| PROT_EXEC,
	409	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \| MAP_EXECUTABLE,
	410	fd_offset);
	411	up_write(&current->mm->mmap_sem);
	412
	413	if (error != N_TXTADDR(ex)) {
	414	send_sig(SIGKILL, current, 0);
	415	return error;
	416	}
	417
	418	down_write(&current->mm->mmap_sem);
	419	error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
	420	PROT_READ \| PROT_WRITE \| PROT_EXEC,
	421	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE \| MAP_EXECUTABLE,
	422	fd_offset + ex.a_text);
	423	up_write(&current->mm->mmap_sem);
	424	if (error != N_DATADDR(ex)) {
	425	send_sig(SIGKILL, current, 0);
	426	return error;
	427	}
	428	}
	429	beyond_if:
	430	set_binfmt(&aout_format);
	431
	432	retval = set_brk(current->mm->start_brk, current->mm->brk);
	433	if (retval < 0) {
	434	send_sig(SIGKILL, current, 0);
	435	return retval;
	436	}
	437
	438	retval = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
	439	if (retval < 0) {
	440	/* Someone check-me: is this error path enough? */
	441	send_sig(SIGKILL, current, 0);
	442	return retval;
	443	}
	444
	445	current->mm->start_stack =
	446	(unsigned long) create_aout_tables((char __user *) bprm->p, bprm);
	447	#ifdef __alpha__
	448	regs->gp = ex.a_gpvalue;
	449	#endif
	450	start_thread(regs, ex.a_entry, current->mm->start_stack);
	451	if (unlikely(current->ptrace & PT_PTRACED)) {
	452	if (current->ptrace & PT_TRACE_EXEC)
453	ptrace_notify ((PTRACE_EVENT_EXEC << 8) \| SIGTRAP);
454	else
455	send_sig(SIGTRAP, current, 0);
456	}
457	return 0;
458	}
459
460	static int load_aout_library(struct file *file)
461	{
462	struct inode * inode;
463	unsigned long bss, start_addr, len;
464	unsigned long error;
465	int retval;
466	struct exec ex;
467
0f7fc9e4	468	inode = file->f_path.dentry->d_inode;
1da177e4 LT	469
	470	retval = -ENOEXEC;
	471	error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
	472	if (error != sizeof(ex))
	473	goto out;
	474
	475	/* We come in here for the regular a.out style of shared libraries */
	476	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) \|\| N_TRSIZE(ex) \|\|
	477	N_DRSIZE(ex) \|\| ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) \|\|
	478	i_size_read(inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
	479	goto out;
	480	}
	481
8454aeef ET	482	/*
	483	* Requires a mmap handler. This prevents people from using a.out
	484	* as part of an exploit attack against /proc-related vulnerabilities.
	485	*/
	486	if (!file->f_op \|\| !file->f_op->mmap)
	487	goto out;
	488
1da177e4 LT	489	if (N_FLAGS(ex))
	490	goto out;
	491
	492	/* For QMAGIC, the starting address is 0x20 into the page. We mask
	493	this off to get the starting address for the page */
	494
	495	start_addr = ex.a_entry & 0xfffff000;
	496
	497	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
	498	static unsigned long error_time;
	499	loff_t pos = N_TXTOFF(ex);
	500
	501	if ((jiffies-error_time) > 5*HZ)
	502	{
	503	printk(KERN_WARNING
	504	"N_TXTOFF is not page aligned. Please convert library: %s\n",
0f7fc9e4	505	file->f_path.dentry->d_name.name);
1da177e4 LT	506	error_time = jiffies;
	507	}
	508	down_write(&current->mm->mmap_sem);
	509	do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
	510	up_write(&current->mm->mmap_sem);
	511
	512	file->f_op->read(file, (char __user *)start_addr,
	513	ex.a_text + ex.a_data, &pos);
	514	flush_icache_range((unsigned long) start_addr,
	515	(unsigned long) start_addr + ex.a_text + ex.a_data);
	516
	517	retval = 0;
	518	goto out;
	519	}
	520	/* Now use mmap to map the library into memory. */
	521	down_write(&current->mm->mmap_sem);
	522	error = do_mmap(file, start_addr, ex.a_text + ex.a_data,
	523	PROT_READ \| PROT_WRITE \| PROT_EXEC,
	524	MAP_FIXED \| MAP_PRIVATE \| MAP_DENYWRITE,
	525	N_TXTOFF(ex));
	526	up_write(&current->mm->mmap_sem);
	527	retval = error;
	528	if (error != start_addr)
	529	goto out;
	530
	531	len = PAGE_ALIGN(ex.a_text + ex.a_data);
	532	bss = ex.a_text + ex.a_data + ex.a_bss;
	533	if (bss > len) {
	534	down_write(&current->mm->mmap_sem);
	535	error = do_brk(start_addr + len, bss - len);
	536	up_write(&current->mm->mmap_sem);
	537	retval = error;
	538	if (error != start_addr + len)
	539	goto out;
	540	}
	541	retval = 0;
	542	out:
	543	return retval;
	544	}
	545
	546	static int __init init_aout_binfmt(void)
	547	{
	548	return register_binfmt(&aout_format);
	549	}
	550
	551	static void __exit exit_aout_binfmt(void)
	552	{
	553	unregister_binfmt(&aout_format);
	554	}
	555
	556	core_initcall(init_aout_binfmt);
	557	module_exit(exit_aout_binfmt);
	558	MODULE_LICENSE("GPL");