fs/binfmt_som.c - linux - Git at Google

 /*
  * linux/fs/binfmt_som.c
  *
  * These are the functions used to load SOM format executables as used
  * by HP-UX.
  *
  * Copyright 1999 Matthew Wilcox <willy@bofh.ai>
  * based on binfmt_elf which is
  * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
  */

 #include <linux/module.h>

 #include <linux/fs.h>
 #include <linux/stat.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
 #include <linux/errno.h>
 #include <linux/signal.h>
 #include <linux/binfmts.h>
 #include <linux/som.h>
 #include <linux/string.h>
 #include <linux/file.h>
 #include <linux/fcntl.h>
 #include <linux/ptrace.h>
 #include <linux/slab.h>
 #include <linux/shm.h>
 #include <linux/personality.h>
 #include <linux/init.h>

 #include <asm/uaccess.h>
 #include <asm/pgtable.h>


 #include <linux/elf.h>

 static int load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs);
 static int load_som_library(struct file *);

 /*
  * If we don't support core dumping, then supply a NULL so we
  * don't even try.
  */
 #if 0
 static int som_core_dump(long signr, struct pt_regs *regs, unsigned long limit);
 #else
 #define som_core_dump	NULL
 #endif

 #define SOM_PAGESTART(_v) ((_v) & ~(unsigned long)(SOM_PAGESIZE-1))
 #define SOM_PAGEOFFSET(_v) ((_v) & (SOM_PAGESIZE-1))
 #define SOM_PAGEALIGN(_v) (((_v) + SOM_PAGESIZE - 1) & ~(SOM_PAGESIZE - 1))

 static struct linux_binfmt som_format = {
 	.module		= THIS_MODULE,
 	.load_binary	= load_som_binary,
 	.load_shlib	= load_som_library,
 	.core_dump	= som_core_dump,
 	.min_coredump	= SOM_PAGESIZE
 };

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

 	/* Word-align the stack pointer */
 	sp = (unsigned long *)((bprm->p + 3) & ~3);

 	envp = (char **) sp;
 	sp += envc + 1;
 	argv = (char **) sp;
 	sp += argc + 1;

 	__put_user((unsigned long) envp,++sp);
 	__put_user((unsigned long) argv,++sp);

 	__put_user(argc, ++sp);

 	bprm->p = (unsigned long) sp;

 	p = current->mm->arg_start;
 	while (argc-- > 0) {
 		__put_user((char *)p,argv++);
 		p += strlen_user((char *)p);
 	}
 	__put_user(NULL, argv);
 	current->mm->arg_end = current->mm->env_start = p;
 	while (envc-- > 0) {
 		__put_user((char *)p,envp++);
 		p += strlen_user((char *)p);
 	}
 	__put_user(NULL, envp);
 	current->mm->env_end = p;
 }

 static int check_som_header(struct som_hdr *som_ex)
 {
 	int *buf = (int *)som_ex;
 	int i, ck;

 	if (som_ex->system_id != SOM_SID_PARISC_1_0 &&
 	    som_ex->system_id != SOM_SID_PARISC_1_1 &&
 	    som_ex->system_id != SOM_SID_PARISC_2_0)
 		return -ENOEXEC;

 	if (som_ex->a_magic != SOM_EXEC_NONSHARE &&
 	    som_ex->a_magic != SOM_EXEC_SHARE &&
 	    som_ex->a_magic != SOM_EXEC_DEMAND)
 		return -ENOEXEC;

 	if (som_ex->version_id != SOM_ID_OLD &&
 	    som_ex->version_id != SOM_ID_NEW)
 		return -ENOEXEC;

 	ck = 0;
 	for (i=0; i<32; i++)
 		ck ^= buf[i];
 	if (ck != 0)
 		return -ENOEXEC;

 	return 0;
 }

 static int map_som_binary(struct file *file,
 		const struct som_exec_auxhdr *hpuxhdr)
 {
 	unsigned long code_start, code_size, data_start, data_size;
 	unsigned long bss_start, som_brk;
 	int retval;
 	int prot = PROT_READ | PROT_EXEC;
 	int flags = MAP_FIXED|MAP_PRIVATE|MAP_DENYWRITE|MAP_EXECUTABLE;

 	mm_segment_t old_fs = get_fs();
 	set_fs(get_ds());

 	code_start = SOM_PAGESTART(hpuxhdr->exec_tmem);
 	code_size = SOM_PAGEALIGN(hpuxhdr->exec_tsize);
 	current->mm->start_code = code_start;
 	current->mm->end_code = code_start + code_size;
 	down_write(&current->mm->mmap_sem);
 	retval = do_mmap(file, code_start, code_size, prot,
 			flags, SOM_PAGESTART(hpuxhdr->exec_tfile));
 	up_write(&current->mm->mmap_sem);
 	if (retval < 0 && retval > -1024)
 		goto out;

 	data_start = SOM_PAGESTART(hpuxhdr->exec_dmem);
 	data_size = SOM_PAGEALIGN(hpuxhdr->exec_dsize);
 	current->mm->start_data = data_start;
 	current->mm->end_data = bss_start = data_start + data_size;
 	down_write(&current->mm->mmap_sem);
 	retval = do_mmap(file, data_start, data_size,
 			prot | PROT_WRITE, flags,
 			SOM_PAGESTART(hpuxhdr->exec_dfile));
 	up_write(&current->mm->mmap_sem);
 	if (retval < 0 && retval > -1024)
 		goto out;

 	som_brk = bss_start + SOM_PAGEALIGN(hpuxhdr->exec_bsize);
 	current->mm->start_brk = current->mm->brk = som_brk;
 	down_write(&current->mm->mmap_sem);
 	retval = do_mmap(NULL, bss_start, som_brk - bss_start,
 			prot | PROT_WRITE, MAP_FIXED | MAP_PRIVATE, 0);
 	up_write(&current->mm->mmap_sem);
 	if (retval > 0 || retval < -1024)
 		retval = 0;
 out:
 	set_fs(old_fs);
 	return retval;
 }


 /*
  * These are the functions used to load SOM executables and shared
  * libraries.  There is no binary dependent code anywhere else.
  */

 static int
 load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs)
 {
 	int som_exec_fileno;
 	int retval;
 	unsigned int size;
 	unsigned long som_entry;
 	struct som_hdr *som_ex;
 	struct som_exec_auxhdr *hpuxhdr;
 	struct files_struct *files;

 	/* Get the exec-header */
 	som_ex = (struct som_hdr *) bprm->buf;

 	retval = check_som_header(som_ex);
 	if (retval != 0)
 		goto out;

 	/* Now read in the auxiliary header information */

 	retval = -ENOMEM;
 	size = som_ex->aux_header_size;
 	if (size > SOM_PAGESIZE)
 		goto out;
 	hpuxhdr = kmalloc(size, GFP_KERNEL);
 	if (!hpuxhdr)
 		goto out;

 	retval = kernel_read(bprm->file, som_ex->aux_header_location,
 			(char *) hpuxhdr, size);
 	if (retval != size) {
 		if (retval >= 0)
 			retval = -EIO;
 		goto out_free;
 	}

 	files = current->files; /* Refcounted so ok */
 	retval = unshare_files();
 	if (retval < 0)
 		goto out_free;
 	if (files == current->files) {
 		put_files_struct(files);
 		files = NULL;
 	}

 	retval = get_unused_fd();
 	if (retval < 0)
 		goto out_free;
 	get_file(bprm->file);
 	fd_install(som_exec_fileno = retval, bprm->file);

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

 	/* OK, This is the point of no return */
 	current->flags &= ~PF_FORKNOEXEC;
 	current->personality = PER_HPUX;

 	/* Set the task size for HP-UX processes such that
 	 * the gateway page is outside the address space.
 	 * This can be fixed later, but for now, this is much
 	 * easier.
 	 */

 	current->thread.task_size = 0xc0000000;

 	/* Set map base to allow enough room for hp-ux heap growth */

 	current->thread.map_base = 0x80000000;

 	retval = map_som_binary(bprm->file, hpuxhdr);
 	if (retval < 0)
 		goto out_free;

 	som_entry = hpuxhdr->exec_entry;
 	kfree(hpuxhdr);

 	set_binfmt(&som_format);
 	compute_creds(bprm);
 	setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);

 	create_som_tables(bprm);

 	current->mm->start_stack = bprm->p;

 #if 0
 	printk("(start_brk) %08lx\n" , (unsigned long) current->mm->start_brk);
 	printk("(end_code) %08lx\n" , (unsigned long) current->mm->end_code);
 	printk("(start_code) %08lx\n" , (unsigned long) current->mm->start_code);
 	printk("(end_data) %08lx\n" , (unsigned long) current->mm->end_data);
 	printk("(start_stack) %08lx\n" , (unsigned long) current->mm->start_stack);
 	printk("(brk) %08lx\n" , (unsigned long) current->mm->brk);
 #endif

 	map_hpux_gateway_page(current,current->mm);

 	start_thread_som(regs, som_entry, bprm->p);
 	if (current->ptrace & PT_PTRACED)
 		send_sig(SIGTRAP, current, 0);
 	return 0;

 	/* error cleanup */
 out_free:
 	kfree(hpuxhdr);
 out:
 	return retval;
 }

 static int load_som_library(struct file *f)
 {
 /* No lib support in SOM yet.  gizza chance.. */
 	return -ENOEXEC;
 }
 	/* Install the SOM loader.
 	 * N.B. We *rely* on the table being the right size with the
 	 * right number of free slots...
 	 */

 static int __init init_som_binfmt(void)
 {
 	return register_binfmt(&som_format);
 }

 static void __exit exit_som_binfmt(void)
 {
 	/* Remove the SOM loader. */
 	unregister_binfmt(&som_format);
 }

 core_initcall(init_som_binfmt);
 module_exit(exit_som_binfmt);
	/*
	* linux/fs/binfmt_som.c
	*
	* These are the functions used to load SOM format executables as used
	* by HP-UX.
	*
	* Copyright 1999 Matthew Wilcox <willy@bofh.ai>
	* based on binfmt_elf which is
	* Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
	*/

	#include <linux/module.h>

	#include <linux/fs.h>
	#include <linux/stat.h>
	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/mman.h>
	#include <linux/errno.h>
	#include <linux/signal.h>
	#include <linux/binfmts.h>
	#include <linux/som.h>
	#include <linux/string.h>
	#include <linux/file.h>
	#include <linux/fcntl.h>
	#include <linux/ptrace.h>
	#include <linux/slab.h>
	#include <linux/shm.h>
	#include <linux/personality.h>
	#include <linux/init.h>

	#include <asm/uaccess.h>
	#include <asm/pgtable.h>


	#include <linux/elf.h>

	static int load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs);
	static int load_som_library(struct file *);

	/*
	* If we don't support core dumping, then supply a NULL so we
	* don't even try.
	*/
	#if 0
	static int som_core_dump(long signr, struct pt_regs *regs, unsigned long limit);
	#else
	#define som_core_dump NULL
	#endif

	#define SOM_PAGESTART(_v) ((_v) & ~(unsigned long)(SOM_PAGESIZE-1))
	#define SOM_PAGEOFFSET(_v) ((_v) & (SOM_PAGESIZE-1))
	#define SOM_PAGEALIGN(_v) (((_v) + SOM_PAGESIZE - 1) & ~(SOM_PAGESIZE - 1))

	static struct linux_binfmt som_format = {
	.module = THIS_MODULE,
	.load_binary = load_som_binary,
	.load_shlib = load_som_library,
	.core_dump = som_core_dump,
	.min_coredump = SOM_PAGESIZE
	};

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

	/* Word-align the stack pointer */
	sp = (unsigned long *)((bprm->p + 3) & ~3);

	envp = (char **) sp;
	sp += envc + 1;
	argv = (char **) sp;
	sp += argc + 1;

	__put_user((unsigned long) envp,++sp);
	__put_user((unsigned long) argv,++sp);

	__put_user(argc, ++sp);

	bprm->p = (unsigned long) sp;

	p = current->mm->arg_start;
	while (argc-- > 0) {
	__put_user((char *)p,argv++);
	p += strlen_user((char *)p);
	}
	__put_user(NULL, argv);
	current->mm->arg_end = current->mm->env_start = p;
	while (envc-- > 0) {
	__put_user((char *)p,envp++);
	p += strlen_user((char *)p);
	}
	__put_user(NULL, envp);
	current->mm->env_end = p;
	}

	static int check_som_header(struct som_hdr *som_ex)
	{
	int buf = (int )som_ex;
	int i, ck;

	if (som_ex->system_id != SOM_SID_PARISC_1_0 &&
	som_ex->system_id != SOM_SID_PARISC_1_1 &&
	som_ex->system_id != SOM_SID_PARISC_2_0)
	return -ENOEXEC;

	if (som_ex->a_magic != SOM_EXEC_NONSHARE &&
	som_ex->a_magic != SOM_EXEC_SHARE &&
	som_ex->a_magic != SOM_EXEC_DEMAND)
	return -ENOEXEC;

	if (som_ex->version_id != SOM_ID_OLD &&
	som_ex->version_id != SOM_ID_NEW)
	return -ENOEXEC;

	ck = 0;
	for (i=0; i<32; i++)
	ck ^= buf[i];
	if (ck != 0)
	return -ENOEXEC;

	return 0;
	}

	static int map_som_binary(struct file *file,
	const struct som_exec_auxhdr *hpuxhdr)
	{
	unsigned long code_start, code_size, data_start, data_size;
	unsigned long bss_start, som_brk;
	int retval;
	int prot = PROT_READ \| PROT_EXEC;
	int flags = MAP_FIXED\|MAP_PRIVATE\|MAP_DENYWRITE\|MAP_EXECUTABLE;

	mm_segment_t old_fs = get_fs();
	set_fs(get_ds());

	code_start = SOM_PAGESTART(hpuxhdr->exec_tmem);
	code_size = SOM_PAGEALIGN(hpuxhdr->exec_tsize);
	current->mm->start_code = code_start;
	current->mm->end_code = code_start + code_size;
	down_write(&current->mm->mmap_sem);
	retval = do_mmap(file, code_start, code_size, prot,
	flags, SOM_PAGESTART(hpuxhdr->exec_tfile));
	up_write(&current->mm->mmap_sem);
	if (retval < 0 && retval > -1024)
	goto out;

	data_start = SOM_PAGESTART(hpuxhdr->exec_dmem);
	data_size = SOM_PAGEALIGN(hpuxhdr->exec_dsize);
	current->mm->start_data = data_start;
	current->mm->end_data = bss_start = data_start + data_size;
	down_write(&current->mm->mmap_sem);
	retval = do_mmap(file, data_start, data_size,
	prot \| PROT_WRITE, flags,
	SOM_PAGESTART(hpuxhdr->exec_dfile));
	up_write(&current->mm->mmap_sem);
	if (retval < 0 && retval > -1024)
	goto out;

	som_brk = bss_start + SOM_PAGEALIGN(hpuxhdr->exec_bsize);
	current->mm->start_brk = current->mm->brk = som_brk;
	down_write(&current->mm->mmap_sem);
	retval = do_mmap(NULL, bss_start, som_brk - bss_start,
	prot \| PROT_WRITE, MAP_FIXED \| MAP_PRIVATE, 0);
	up_write(&current->mm->mmap_sem);
	if (retval > 0 \|\| retval < -1024)
	retval = 0;
	out:
	set_fs(old_fs);
	return retval;
	}


	/*
	* These are the functions used to load SOM executables and shared
	* libraries. There is no binary dependent code anywhere else.
	*/

	static int
	load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs)
	{
	int som_exec_fileno;
	int retval;
	unsigned int size;
	unsigned long som_entry;
	struct som_hdr *som_ex;
	struct som_exec_auxhdr *hpuxhdr;
	struct files_struct *files;

	/* Get the exec-header */
	som_ex = (struct som_hdr *) bprm->buf;

	retval = check_som_header(som_ex);
	if (retval != 0)
	goto out;

	/* Now read in the auxiliary header information */

	retval = -ENOMEM;
	size = som_ex->aux_header_size;
	if (size > SOM_PAGESIZE)
	goto out;
	hpuxhdr = kmalloc(size, GFP_KERNEL);
	if (!hpuxhdr)
	goto out;

	retval = kernel_read(bprm->file, som_ex->aux_header_location,
	(char *) hpuxhdr, size);
	if (retval != size) {
	if (retval >= 0)
	retval = -EIO;
	goto out_free;
	}

	files = current->files; /* Refcounted so ok */
	retval = unshare_files();
	if (retval < 0)
	goto out_free;
	if (files == current->files) {
	put_files_struct(files);
	files = NULL;
	}

	retval = get_unused_fd();
	if (retval < 0)
	goto out_free;
	get_file(bprm->file);
	fd_install(som_exec_fileno = retval, bprm->file);

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

	/* OK, This is the point of no return */
	current->flags &= ~PF_FORKNOEXEC;
	current->personality = PER_HPUX;

	/* Set the task size for HP-UX processes such that
	* the gateway page is outside the address space.
	* This can be fixed later, but for now, this is much
	* easier.
	*/

	current->thread.task_size = 0xc0000000;

	/* Set map base to allow enough room for hp-ux heap growth */

	current->thread.map_base = 0x80000000;

	retval = map_som_binary(bprm->file, hpuxhdr);
	if (retval < 0)
	goto out_free;

	som_entry = hpuxhdr->exec_entry;
	kfree(hpuxhdr);

	set_binfmt(&som_format);
	compute_creds(bprm);
	setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);

	create_som_tables(bprm);

	current->mm->start_stack = bprm->p;

	#if 0
	printk("(start_brk) %08lx\n" , (unsigned long) current->mm->start_brk);
	printk("(end_code) %08lx\n" , (unsigned long) current->mm->end_code);
	printk("(start_code) %08lx\n" , (unsigned long) current->mm->start_code);
	printk("(end_data) %08lx\n" , (unsigned long) current->mm->end_data);
	printk("(start_stack) %08lx\n" , (unsigned long) current->mm->start_stack);
	printk("(brk) %08lx\n" , (unsigned long) current->mm->brk);
	#endif

	map_hpux_gateway_page(current,current->mm);

	start_thread_som(regs, som_entry, bprm->p);
	if (current->ptrace & PT_PTRACED)
	send_sig(SIGTRAP, current, 0);
	return 0;

	/* error cleanup */
	out_free:
	kfree(hpuxhdr);
	out:
	return retval;
	}

	static int load_som_library(struct file *f)
	{
	/* No lib support in SOM yet. gizza chance.. */
	return -ENOEXEC;
	}
	/* Install the SOM loader.
	* N.B. We rely on the table being the right size with the
	* right number of free slots...
	*/

	static int __init init_som_binfmt(void)
	{
	return register_binfmt(&som_format);
	}

	static void __exit exit_som_binfmt(void)
	{
	/* Remove the SOM loader. */
	unregister_binfmt(&som_format);
	}

	core_initcall(init_som_binfmt);
	module_exit(exit_som_binfmt);