Fixed the chroot option.v_2_4_22_1

1 files changed, 55 insertions, 20 deletions

diff --git a/arch/um/fs/hostfs/hostfs_kern.c b/arch/um/fs/hostfs/hostfs_kern.c
index 3a50894..bb6668b 100644
--- a/arch/um/fs/hostfs/hostfs_kern.c
+++ b/arch/um/fs/hostfs/hostfs_kern.c
@@ -1,5 +1,5 @@
 /* 
- * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
  * Licensed under the GPL
  */
 
@@ -30,8 +30,10 @@ struct dentry_operations hostfs_dentry_ops = {
 	.d_delete		= hostfs_d_delete,
 };
 
+#define DEFAULT_ROOT "/"
+
 /* Changed in hostfs_args before the kernel starts running */
-static char *root_ino = "/";
+static char *jail_dir = NULL;
 static int append = 0;
 
 #define HOSTFS_SUPER_MAGIC 0x00c0ffee
@@ -48,7 +50,7 @@ static int __init hostfs_args(char *options, int *add)
 	if(ptr != NULL)
 		*ptr++ = '\0';
 	if(*options != '\0')
-		root_ino = options;
+		jail_dir = options;
 
 	options = ptr;
 	while(options){
@@ -529,6 +531,7 @@ static struct inode *get_inode(struct super_block *sb, struct dentry *dentry,
 	if(error) *error = err;
 	return(inode);
  out_put:
+	make_bad_inode(inode);
 	iput(inode);
  out:
 	if(error) *error = err;
@@ -858,43 +861,75 @@ static struct address_space_operations hostfs_link_aops = {
 	.readpage	= hostfs_link_readpage,
 };
 
-static struct super_block *hostfs_read_super_common(struct super_block *sb, 
-						    char *data)
+static char *get_root(char *mount_arg)
+{
+	char *root, *slash = "";
+	int len = 0;
+
+	if(jail_dir != NULL){
+		len += strlen(jail_dir);
+		if((*jail_dir == '\0') || 
+		   (jail_dir[strlen(jail_dir) - 1] != '/'))
+			slash = "/";
+		len += strlen(slash);
+	}
+
+	if(mount_arg == NULL)
+		mount_arg = DEFAULT_ROOT;
+
+	len += strlen(mount_arg) + 1;
+
+	root = kmalloc(len, GFP_KERNEL);
+	if(root == NULL)
+		return(NULL);
+
+	if(jail_dir != NULL)
+		sprintf(root, "%s%s%s", jail_dir, slash, mount_arg);
+	else
+		strcpy(root, mount_arg);
+
+	return(root);
+}
+
+struct super_block *hostfs_read_super(struct super_block *sb, void *data, 
+				      int silent)
 {
 	struct inode *root_inode;
-	char *name;
+	char *root_dir;
 
 	sb->s_blocksize = 1024;
 	sb->s_blocksize_bits = 10;
 	sb->s_magic = HOSTFS_SUPER_MAGIC;
 	sb->s_op = &hostfs_sbops;
-	if((data == NULL) || (*((char *) data) == '\0')) data = root_ino;
-	name = kmalloc(strlen(data) + 1, GFP_KERNEL);
-	if(name == NULL) return(NULL);
-	strcpy(name, data);
+
 	root_inode = get_inode(sb, NULL, NULL);
 	if(root_inode == NULL)
-		goto out_free;
+		goto out;
+
+	root_dir = get_root(data);
+	if(root_dir == NULL)
+		goto out_put;
 
-	root_inode->u.hostfs_i.host_filename = name;
+	root_inode->u.hostfs_i.host_filename = root_dir;
 	sb->s_root = d_alloc_root(root_inode);
+	if(sb->s_root == NULL)
+		goto out_free;
+
 	if(read_inode(root_inode))
-		goto out_put;
+		goto out_dput;
 	return(sb);
 
+ out_dput:
+	dput(sb->s_root);
  out_free:
-	kfree(name);
+	kfree(root_dir);
  out_put:
+	make_bad_inode(root_inode);
 	iput(root_inode);
+ out:
 	return(NULL);
 }
 
-struct super_block *hostfs_read_super(struct super_block *sb, void *data, 
-				      int silent)
-{
-	return(hostfs_read_super_common(sb, data));
-}
-
 DECLARE_FSTYPE(hostfs_type, "hostfs", hostfs_read_super, 0);
 
 static int __init init_hostfs(void)