1 files changed, 56 insertions, 110 deletions

diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
index 6a7b730c206..b60500300dd 100644
--- a/fs/binfmt_misc.c
+++ b/fs/binfmt_misc.c
@@ -1,7 +1,7 @@
 /*
  *  binfmt_misc.c
  *
- *  Copyright (C) 1997 Richard Günther
+ *  Copyright (C) 1997 Richard Günther
  *
  *  binfmt_misc detects binaries via a magic or filename extension and invokes
  *  a specified wrapper. This should obsolete binfmt_java, binfmt_em86 and
@@ -18,15 +18,18 @@
 
 #include <linux/module.h>
 #include <linux/init.h>
-
+#include <linux/sched.h>
+#include <linux/magic.h>
 #include <linux/binfmts.h>
 #include <linux/slab.h>
 #include <linux/ctype.h>
+#include <linux/string_helpers.h>
 #include <linux/file.h>
 #include <linux/pagemap.h>
 #include <linux/namei.h>
 #include <linux/mount.h>
 #include <linux/syscalls.h>
+#include <linux/fs.h>
 
 #include <asm/uaccess.h>
 
@@ -55,6 +58,7 @@ typedef struct {
 } Node;
 
 static DEFINE_RWLOCK(entries_lock);
+static struct file_system_type bm_fs_type;
 static struct vfsmount *bm_mnt;
 static int entry_count;
 
@@ -101,15 +105,14 @@ static Node *check_file(struct linux_binprm *bprm)
 /*
  * the loader itself
  */
-static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs)
+static int load_misc_binary(struct linux_binprm *bprm)
 {
 	Node *fmt;
 	struct file * interp_file = NULL;
 	char iname[BINPRM_BUF_SIZE];
-	char *iname_addr = iname;
+	const char *iname_addr = iname;
 	int retval;
 	int fd_binary = -1;
-	struct files_struct *files = NULL;
 
 	retval = -ENOEXEC;
 	if (!enabled)
@@ -125,33 +128,26 @@ static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs)
 		goto _ret;
 
 	if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {
-		remove_arg_zero(bprm);
+		retval = remove_arg_zero(bprm);
+		if (retval)
+			goto _ret;
 	}
 
 	if (fmt->flags & MISC_FMT_OPEN_BINARY) {
 
-		files = current->files;
-		retval = unshare_files();
-		if (retval < 0)
-			goto _ret;
-		if (files == current->files) {
-			put_files_struct(files);
-			files = NULL;
-		}
 		/* if the binary should be opened on behalf of the
 		 * interpreter than keep it open and assign descriptor
 		 * to it */
  		fd_binary = get_unused_fd();
  		if (fd_binary < 0) {
  			retval = fd_binary;
- 			goto _unshare;
+ 			goto _ret;
  		}
  		fd_install(fd_binary, bprm->file);
 
 		/* if the binary is not readable than enforce mm->dumpable=0
 		   regardless of the interpreter's permissions */
-		if (file_permission(bprm->file, MAY_READ))
-			bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
+		would_dump(bprm, bprm->file);
 
 		allow_write_access(bprm->file);
 		bprm->file = NULL;
@@ -177,7 +173,10 @@ static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs)
 		goto _error;
 	bprm->argc ++;
 
-	bprm->interp = iname;	/* for binfmt_script */
+	/* Update interp in case binfmt_script needs it. */
+	retval = bprm_change_interp(iname, bprm);
+	if (retval < 0)
+		goto _error;
 
 	interp_file = open_exec (iname);
 	retval = PTR_ERR (interp_file);
@@ -198,15 +197,10 @@ static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs)
 	if (retval < 0)
 		goto _error;
 
-	retval = search_binary_handler (bprm, regs);
+	retval = search_binary_handler(bprm);
 	if (retval < 0)
 		goto _error;
 
-	if (files) {
-		steal_locks(files);
-		put_files_struct(files);
-		files = NULL;
-	}
 _ret:
 	return retval;
 _error:
@@ -214,11 +208,6 @@ _error:
 		sys_close(fd_binary);
 	bprm->interp_flags = 0;
 	bprm->interp_data = 0;
-_unshare:
-	if (files) {
-		put_files_struct(current->files);
-		current->files = files;
-	}
 	goto _ret;
 }
 
@@ -246,24 +235,6 @@ static char *scanarg(char *s, char del)
 	return s;
 }
 
-static int unquote(char *from)
-{
-	char c = 0, *s = from, *p = from;
-
-	while ((c = *s++) != '\0') {
-		if (c == '\\' && *s == 'x') {
-			s++;
-			c = toupper(*s++);
-			*p = (c - (isdigit(c) ? '0' : 'A' - 10)) << 4;
-			c = toupper(*s++);
-			*p++ |= c - (isdigit(c) ? '0' : 'A' - 10);
-			continue;
-		}
-		*p++ = c;
-	}
-	return p - from;
-}
-
 static char * check_special_flags (char * sfs, Node * e)
 {
 	char * p = sfs;
@@ -313,7 +284,7 @@ static Node *create_entry(const char __user *buffer, size_t count)
 
 	err = -ENOMEM;
 	memsize = sizeof(Node) + count + 8;
-	e = (Node *) kmalloc(memsize, GFP_USER);
+	e = kmalloc(memsize, GFP_USER);
 	if (!e)
 		goto out;
 
@@ -366,8 +337,9 @@ static Node *create_entry(const char __user *buffer, size_t count)
 		p[-1] = '\0';
 		if (!e->mask[0])
 			e->mask = NULL;
-		e->size = unquote(e->magic);
-		if (e->mask && unquote(e->mask) != e->size)
+		e->size = string_unescape_inplace(e->magic, UNESCAPE_HEX);
+		if (e->mask &&
+		    string_unescape_inplace(e->mask, UNESCAPE_HEX) != e->size)
 			goto Einval;
 		if (e->size + e->offset > BINPRM_BUF_SIZE)
 			goto Einval;
@@ -504,20 +476,18 @@ static struct inode *bm_get_inode(struct super_block *sb, int mode)
 	struct inode * inode = new_inode(sb);
 
 	if (inode) {
+		inode->i_ino = get_next_ino();
 		inode->i_mode = mode;
-		inode->i_uid = 0;
-		inode->i_gid = 0;
-		inode->i_blksize = PAGE_CACHE_SIZE;
-		inode->i_blocks = 0;
 		inode->i_atime = inode->i_mtime = inode->i_ctime =
 			current_fs_time(inode->i_sb);
 	}
 	return inode;
 }
 
-static void bm_clear_inode(struct inode *inode)
+static void bm_evict_inode(struct inode *inode)
 {
-	kfree(inode->u.generic_ip);
+	clear_inode(inode);
+	kfree(inode->i_private);
 }
 
 static void kill_node(Node *e)
@@ -533,7 +503,7 @@ static void kill_node(Node *e)
 	write_unlock(&entries_lock);
 
 	if (dentry) {
-		dentry->d_inode->i_nlink--;
+		drop_nlink(dentry->d_inode);
 		d_drop(dentry);
 		dput(dentry);
 		simple_release_fs(&bm_mnt, &entry_count);
@@ -545,32 +515,17 @@ static void kill_node(Node *e)
 static ssize_t
 bm_entry_read(struct file * file, char __user * buf, size_t nbytes, loff_t *ppos)
 {
-	Node *e = file->f_dentry->d_inode->u.generic_ip;
-	loff_t pos = *ppos;
+	Node *e = file_inode(file)->i_private;
 	ssize_t res;
 	char *page;
-	int len;
 
 	if (!(page = (char*) __get_free_page(GFP_KERNEL)))
 		return -ENOMEM;
 
 	entry_status(e, page);
-	len = strlen(page);
 
-	res = -EINVAL;
-	if (pos < 0)
-		goto out;
-	res = 0;
-	if (pos >= len)
-		goto out;
-	if (len < pos + nbytes)
-		nbytes = len - pos;
-	res = -EFAULT;
-	if (copy_to_user(buf, page + pos, nbytes))
-		goto out;
-	*ppos = pos + nbytes;
-	res = nbytes;
-out:
+	res = simple_read_from_buffer(buf, nbytes, ppos, page, strlen(page));
+
 	free_page((unsigned long) page);
 	return res;
 }
@@ -579,7 +534,7 @@ static ssize_t bm_entry_write(struct file *file, const char __user *buffer,
 				size_t count, loff_t *ppos)
 {
 	struct dentry *root;
-	Node *e = file->f_dentry->d_inode->u.generic_ip;
+	Node *e = file_inode(file)->i_private;
 	int res = parse_command(buffer, count);
 
 	switch (res) {
@@ -587,7 +542,7 @@ static ssize_t bm_entry_write(struct file *file, const char __user *buffer,
 			break;
 		case 2: set_bit(Enabled, &e->flags);
 			break;
-		case 3: root = dget(file->f_vfsmnt->mnt_sb->s_root);
+		case 3: root = dget(file->f_path.dentry->d_sb->s_root);
 			mutex_lock(&root->d_inode->i_mutex);
 
 			kill_node(e);
@@ -600,9 +555,10 @@ static ssize_t bm_entry_write(struct file *file, const char __user *buffer,
 	return count;
 }
 
-static struct file_operations bm_entry_operations = {
+static const struct file_operations bm_entry_operations = {
 	.read		= bm_entry_read,
 	.write		= bm_entry_write,
+	.llseek		= default_llseek,
 };
 
 /* /register */
@@ -613,7 +569,7 @@ static ssize_t bm_register_write(struct file *file, const char __user *buffer,
 	Node *e;
 	struct inode *inode;
 	struct dentry *root, *dentry;
-	struct super_block *sb = file->f_vfsmnt->mnt_sb;
+	struct super_block *sb = file->f_path.dentry->d_sb;
 	int err = 0;
 
 	e = create_entry(buffer, count);
@@ -638,7 +594,7 @@ static ssize_t bm_register_write(struct file *file, const char __user *buffer,
 	if (!inode)
 		goto out2;
 
-	err = simple_pin_fs("binfmt_misc", &bm_mnt, &entry_count);
+	err = simple_pin_fs(&bm_fs_type, &bm_mnt, &entry_count);
 	if (err) {
 		iput(inode);
 		inode = NULL;
@@ -646,7 +602,7 @@ static ssize_t bm_register_write(struct file *file, const char __user *buffer,
 	}
 
 	e->dentry = dget(dentry);
-	inode->u.generic_ip = e;
+	inode->i_private = e;
 	inode->i_fop = &bm_entry_operations;
 
 	d_instantiate(dentry, inode);
@@ -668,8 +624,9 @@ out:
 	return count;
 }
 
-static struct file_operations bm_register_operations = {
+static const struct file_operations bm_register_operations = {
 	.write		= bm_register_write,
+	.llseek		= noop_llseek,
 };
 
 /* /status */
@@ -677,20 +634,9 @@ static struct file_operations bm_register_operations = {
 static ssize_t
 bm_status_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
 {
-	char *s = enabled ? "enabled" : "disabled";
-	int len = strlen(s);
-	loff_t pos = *ppos;
+	char *s = enabled ? "enabled\n" : "disabled\n";
 
-	if (pos < 0)
-		return -EINVAL;
-	if (pos >= len)
-		return 0;
-	if (len < pos + nbytes)
-		nbytes = len - pos;
-	if (copy_to_user(buf, s + pos, nbytes))
-		return -EFAULT;
-	*ppos = pos + nbytes;
-	return nbytes;
+	return simple_read_from_buffer(buf, nbytes, ppos, s, strlen(s));
 }
 
 static ssize_t bm_status_write(struct file * file, const char __user * buffer,
@@ -702,7 +648,7 @@ static ssize_t bm_status_write(struct file * file, const char __user * buffer,
 	switch (res) {
 		case 1: enabled = 0; break;
 		case 2: enabled = 1; break;
-		case 3: root = dget(file->f_vfsmnt->mnt_sb->s_root);
+		case 3: root = dget(file->f_path.dentry->d_sb->s_root);
 			mutex_lock(&root->d_inode->i_mutex);
 
 			while (!list_empty(&entries))
@@ -710,40 +656,42 @@ static ssize_t bm_status_write(struct file * file, const char __user * buffer,
 
 			mutex_unlock(&root->d_inode->i_mutex);
 			dput(root);
+			break;
 		default: return res;
 	}
 	return count;
 }
 
-static struct file_operations bm_status_operations = {
+static const struct file_operations bm_status_operations = {
 	.read		= bm_status_read,
 	.write		= bm_status_write,
+	.llseek		= default_llseek,
 };
 
 /* Superblock handling */
 
-static struct super_operations s_ops = {
+static const struct super_operations s_ops = {
 	.statfs		= simple_statfs,
-	.clear_inode	= bm_clear_inode,
+	.evict_inode	= bm_evict_inode,
 };
 
 static int bm_fill_super(struct super_block * sb, void * data, int silent)
 {
 	static struct tree_descr bm_files[] = {
-		[1] = {"status", &bm_status_operations, S_IWUSR|S_IRUGO},
-		[2] = {"register", &bm_register_operations, S_IWUSR},
+		[2] = {"status", &bm_status_operations, S_IWUSR|S_IRUGO},
+		[3] = {"register", &bm_register_operations, S_IWUSR},
 		/* last one */ {""}
 	};
-	int err = simple_fill_super(sb, 0x42494e4d, bm_files);
+	int err = simple_fill_super(sb, BINFMTFS_MAGIC, bm_files);
 	if (!err)
 		sb->s_op = &s_ops;
 	return err;
 }
 
-static struct super_block *bm_get_sb(struct file_system_type *fs_type,
+static struct dentry *bm_mount(struct file_system_type *fs_type,
 	int flags, const char *dev_name, void *data)
 {
-	return get_sb_single(fs_type, flags, data, bm_fill_super);
+	return mount_single(fs_type, flags, data, bm_fill_super);
 }
 
 static struct linux_binfmt misc_format = {
@@ -754,18 +702,16 @@ static struct linux_binfmt misc_format = {
 static struct file_system_type bm_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "binfmt_misc",
-	.get_sb		= bm_get_sb,
+	.mount		= bm_mount,
 	.kill_sb	= kill_litter_super,
 };
+MODULE_ALIAS_FS("binfmt_misc");
 
 static int __init init_misc_binfmt(void)
 {
 	int err = register_filesystem(&bm_fs_type);
-	if (!err) {
-		err = register_binfmt(&misc_format);
-		if (err)
-			unregister_filesystem(&bm_fs_type);
-	}
+	if (!err)
+		insert_binfmt(&misc_format);
 	return err;
 }