vserver 1.9.3

[linux-2.6.git] / kernel / vserver / namespace.c

diff --git a/kernel/vserver/namespace.c b/kernel/vserver/namespace.c
index 3dc0f35..ee60d4b 100644 (file)
--- a/kernel/vserver/namespace.c
+++ b/kernel/vserver/namespace.c
@@ -17,11 +17,57 @@
 #include <linux/vs_context.h>
 #include <linux/namespace.h>
 #include <linux/dcache.h>
+#include <linux/fs.h>
 
 #include <asm/errno.h>
 #include <asm/uaccess.h>
 
 
+int vx_check_vfsmount(struct vx_info *vxi, struct vfsmount *mnt)
+{
+       struct vfsmount *root_mnt, *altroot_mnt;
+       struct dentry *root, *altroot, *point;
+       int r1, r2, s1, s2, ret = 0;
+
+       if (!vxi || !mnt)
+               return 1;
+
+       spin_lock(&dcache_lock);
+       altroot_mnt = current->fs->rootmnt;
+       altroot = current->fs->root;
+       point = altroot;
+
+       if (vxi->vx_fs) {
+               root_mnt = vxi->vx_fs->rootmnt;
+               root = vxi->vx_fs->root;
+       } else {
+               root_mnt = altroot_mnt;
+               root = altroot;
+       }
+       /* printk("··· %p:%p/%p:%p ",
+               root_mnt, root, altroot_mnt, altroot);  */
+
+       while ((mnt != mnt->mnt_parent) &&
+               (mnt != root_mnt) && (mnt != altroot_mnt)) {
+               point = mnt->mnt_mountpoint;
+               mnt = mnt->mnt_parent;
+       }
+
+       r1 = (mnt == root_mnt);
+       s1 = is_subdir(point, root);
+       r2 = (mnt == altroot_mnt);
+       s2 = is_subdir(point, altroot);
+
+       ret = (((mnt == root_mnt) && is_subdir(point, root)) ||
+               ((mnt == altroot_mnt) && is_subdir(point, altroot)));
+       /* printk("··· for %p:%p -> %d:%d/%d:%d = %d\n",
+               mnt, point, r1, s1, r2, s2, ret);       */
+       spin_unlock(&dcache_lock);
+
+       return (r2 && s2);
+}
+
+
 /* virtual host info names */
 
 static char * vx_vhi_name(struct vx_info *vxi, int id)
@@ -57,11 +103,11 @@ int vc_set_vhi_name(uint32_t id, void __user *data)
                return -EPERM;
        if (copy_from_user (&vc_data, data, sizeof(vc_data)))
                return -EFAULT;
-       
+
        vxi = locate_vx_info(id);
        if (!vxi)
                return -ESRCH;
-       
+
        name = vx_vhi_name(vxi, vc_data.field);
        if (name)
                memcpy(name, vc_data.name, 65);
@@ -85,7 +131,7 @@ int vc_get_vhi_name(uint32_t id, void __user *data)
        name = vx_vhi_name(vxi, vc_data.field);
        if (!name)
                goto out_put;
-                       
+
        memcpy(vc_data.name, name, 65);
        if (copy_to_user (data, &vc_data, sizeof(vc_data)))
                return -EFAULT;
@@ -145,7 +191,7 @@ int vc_enter_namespace(uint32_t id, void *data)
        old_ns = current->namespace;
        old_fs = current->fs;
        get_namespace(vxi->vx_namespace);
-       current->namespace = vxi->vx_namespace; 
+       current->namespace = vxi->vx_namespace;
        current->fs = fs;
        task_unlock(current);