patch/ms_permission.patch

--- /store/linux/linux-2.4.14.tar.gz#/linux/fs/namespace.c	Fri Nov  9 08:58:10 2001
+++ linux/fs/namespace.c	Fri Nov  9 09:31:04 2001
@@ -478,20 +478,15 @@
 
 static int mount_is_safe(struct nameidata *nd)
 {
-	if (capable(CAP_SYS_ADMIN))
-		return 0;
-	return -EPERM;
-#ifdef notyet
 	if (S_ISLNK(nd->dentry->d_inode->i_mode))
 		return -EPERM;
 	if (nd->dentry->d_inode->i_mode & S_ISVTX) {
-		if (current->uid != nd->dentry->d_inode->i_uid)
+		if (current->fsuid != nd->dentry->d_inode->i_uid)
 			return -EPERM;
 	}
 	if (permission(nd->dentry->d_inode, MAY_WRITE))
 		return -EPERM;
 	return 0;
-#endif
 }
 
 static struct vfsmount *copy_tree(struct vfsmount *mnt, struct dentry *dentry)
@@ -570,9 +565,10 @@
 {
 	struct nameidata old_nd;
 	struct vfsmount *mnt = NULL;
-	int err = mount_is_safe(nd);
-	if (err)
-		return err;
+	int err = 0;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
 	if (!old_name || !*old_name)
 		return -EINVAL;
 	if (path_init(old_name, LOOKUP_POSITIVE|LOOKUP_FOLLOW, &old_nd))
@@ -741,6 +737,13 @@
 		retval = path_walk(dir_name, &nd);
 	if (retval)
 		return retval;
+
+	if (flags & MS_PERMISSION) {
+		retval = mount_is_safe(&nd);
+		if(retval)
+			return retval;
+	}
+	flags &= ~MS_PERMISSION;
 
 	if (flags & MS_REMOUNT)
 		retval = do_remount(&nd, flags & ~MS_REMOUNT, mnt_flags,
--- /store/linux/linux-2.4.14.tar.gz#/linux/include/linux/fs.h	Fri Nov  9 08:58:51 2001
+++ linux/include/linux/fs.h	Fri Nov  9 09:24:21 2001
@@ -105,6 +105,7 @@
 #define MS_SYNCHRONOUS	16	/* Writes are synced at once */
 #define MS_REMOUNT	32	/* Alter flags of a mounted FS */
 #define MS_MANDLOCK	64	/* Allow mandatory locks on an FS */
+#define MS_PERMISSION	128	/* Check write permission on mount target */
 #define MS_NOATIME	1024	/* Do not update access times. */
 #define MS_NODIRATIME	2048	/* Do not update directory access times */
 #define MS_BIND		4096