- sync fedora branch: will help future merges

- re-apply partially dropped bind mount patch (this time from
  patch-2.6.11-rc5-bme0.06.1.diff)
- sync vserver branch; move check for PROC_SUPER_MAGIC to the right (?)
  place (at least the same place it's at in the stable
  planetlab-3_1-branch)

diff --git a/fs/namei.c b/fs/namei.c
index af91a7c..a9d76b4 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -253,13 +253,14 @@ static inline int xid_permission(struct inode *inode, int mask, struct nameidata
 int permission(struct inode *inode, int mask, struct nameidata *nd)
 {
        int retval, submask;
-       umode_t mode = inode->i_mode;
 
        if (mask & MAY_WRITE) {
+               umode_t mode = inode->i_mode;
+
                /*
                 * Nobody gets write access to a read-only fs.
                 */
-               if (IS_RDONLY(inode) &&
+               if ((IS_RDONLY(inode) || (nd && MNT_IS_RDONLY(nd->mnt))) &&
                    (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
                        return -EROFS;
 
@@ -270,11 +271,9 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
                        return -EACCES;
        }
 
+
        /* Ordinary permission routines do not understand MAY_APPEND. */
        submask = mask & ~MAY_APPEND;
-       if (nd && (mask & MAY_WRITE) && MNT_IS_RDONLY(nd->mnt) &&
-               (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
-               return -EROFS;
        if ((retval = xid_permission(inode, mask, nd)))
                return retval;
        if (inode->i_op && inode->i_op->permission)
@@ -716,6 +715,12 @@ static int do_lookup(struct nameidata *nd, struct qstr *name,
        inode = dentry->d_inode;
        if (!inode)
                goto done;
+       if (inode->i_sb->s_magic == PROC_SUPER_MAGIC) {
+               struct proc_dir_entry *de = PDE(inode);
+
+               if (de && !vx_hide_check(0, de->vx_flags))
+                       goto hidden;
+       }
 #ifdef CONFIG_VSERVER_FILESHARING
        /* MEF: PlanetLab FS module assumes that any file that can be
         * named (e.g., via a cross mount) is not hidden from another
@@ -728,12 +733,6 @@ static int do_lookup(struct nameidata *nd, struct qstr *name,
 #endif
        if (!vx_check(inode->i_xid, VX_WATCH|VX_ADMIN|VX_HOSTID|VX_IDENT))
                goto hidden;
-       if (inode->i_sb->s_magic == PROC_SUPER_MAGIC) {
-               struct proc_dir_entry *de = PDE(inode);
-
-               if (de && !vx_hide_check(0, de->vx_flags))
-                       goto hidden;
-       }
 done:
        path->mnt = mnt;
        path->dentry = dentry;
@@ -1246,7 +1245,8 @@ static inline int check_sticky(struct inode *dir, struct inode *inode)
  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
  *     nfs_async_unlink().
  */
-static inline int may_delete(struct inode *dir,struct dentry *victim,int isdir)
+static inline int may_delete(struct inode *dir, struct dentry *victim,
+       int isdir, struct nameidata *nd)
 {
        int error;
 
@@ -1255,7 +1255,7 @@ static inline int may_delete(struct inode *dir,struct dentry *victim,int isdir)
 
        BUG_ON(victim->d_parent->d_inode != dir);
 
-       error = permission(dir,MAY_WRITE | MAY_EXEC, NULL);
+       error = permission(dir,MAY_WRITE | MAY_EXEC, nd);
        if (error)
                return error;
        if (IS_APPEND(dir))
@@ -1295,24 +1295,6 @@ static inline int may_create(struct inode *dir, struct dentry *child,
        return permission(dir,MAY_WRITE | MAY_EXEC, nd);
 }
 
-static inline int mnt_may_create(struct vfsmount *mnt, struct inode *dir, struct dentry *child) {
-       if (child->d_inode)
-               return -EEXIST;
-       if (IS_DEADDIR(dir))
-               return -ENOENT;
-       if (mnt->mnt_flags & MNT_RDONLY)
-               return -EROFS;
-       return 0;
-}
-
-static inline int mnt_may_unlink(struct vfsmount *mnt, struct inode *dir, struct dentry *child) {
-       if (!child->d_inode)
-               return -ENOENT;
-       if (mnt->mnt_flags & MNT_RDONLY)
-               return -EROFS;
-       return 0;
-}
-
 /* 
  * Special case: O_CREAT|O_EXCL implies O_NOFOLLOW for security
  * reasons.
@@ -1436,7 +1418,7 @@ int may_open(struct nameidata *nd, int acc_mode, int flag)
                        return -EACCES;
 
                flag &= ~O_TRUNC;
-       } else if ((IS_RDONLY(inode) || (nd && MNT_IS_RDONLY(nd->mnt)))
+       } else if ((IS_RDONLY(inode) || MNT_IS_RDONLY(nd->mnt))
                && (flag & FMODE_WRITE))
                return -EROFS;
        /*
@@ -1669,34 +1651,30 @@ do_link:
 struct dentry *lookup_create(struct nameidata *nd, int is_dir)
 {
        struct dentry *dentry;
-       int error;
 
        down(&nd->dentry->d_inode->i_sem);
-       error = -EEXIST;
+       dentry = ERR_PTR(-EEXIST);
        if (nd->last_type != LAST_NORM)
-               goto out;
+               goto fail;
        nd->flags &= ~LOOKUP_PARENT;
        dentry = lookup_hash(&nd->last, nd->dentry);
        if (IS_ERR(dentry))
-               goto ret;
-       error = mnt_may_create(nd->mnt, nd->dentry->d_inode, dentry);
-       if (error)
                goto fail;
-       error = -ENOENT;
        if (!is_dir && nd->last.name[nd->last.len] && !dentry->d_inode)
-               goto fail;
-ret:
+               goto enoent;
        return dentry;
-fail:
+enoent:
        dput(dentry);
-out:
-       return ERR_PTR(error);
+       dentry = ERR_PTR(-ENOENT);
+fail:
+       return dentry;
 }
 EXPORT_SYMBOL_GPL(lookup_create);
 
-int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
+int vfs_mknod(struct inode *dir, struct dentry *dentry,
+       int mode, dev_t dev, struct nameidata *nd)
 {
-       int error = may_create(dir, dentry, NULL);
+       int error = may_create(dir, dentry, nd);
 
        if (error)
                return error;
@@ -1738,7 +1716,6 @@ asmlinkage long sys_mknod(const char __user * filename, int mode, unsigned dev)
                goto out;
        dentry = lookup_create(&nd, 0);
        error = PTR_ERR(dentry);
-
        if (!IS_POSIXACL(nd.dentry->d_inode))
                mode &= ~current->fs->umask;
        if (!IS_ERR(dentry)) {
@@ -1747,11 +1724,12 @@ asmlinkage long sys_mknod(const char __user * filename, int mode, unsigned dev)
                        error = vfs_create(nd.dentry->d_inode,dentry,mode,&nd);
                        break;
                case S_IFCHR: case S_IFBLK:
-                       error = vfs_mknod(nd.dentry->d_inode,dentry,mode,
-                                       new_decode_dev(dev));
+                       error = vfs_mknod(nd.dentry->d_inode, dentry, mode,
+                                       new_decode_dev(dev), &nd);
                        break;
                case S_IFIFO: case S_IFSOCK:
-                       error = vfs_mknod(nd.dentry->d_inode,dentry,mode,0);
+                       error = vfs_mknod(nd.dentry->d_inode, dentry, mode,
+                                       0, &nd);
                        break;
                case S_IFDIR:
                        error = -EPERM;
@@ -1769,9 +1747,10 @@ out:
        return error;
 }
 
-int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+int vfs_mkdir(struct inode *dir, struct dentry *dentry,
+       int mode, struct nameidata *nd)
 {
-       int error = may_create(dir, dentry, NULL);
+       int error = may_create(dir, dentry, nd);
 
        if (error)
                return error;
@@ -1812,7 +1791,8 @@ asmlinkage long sys_mkdir(const char __user * pathname, int mode)
                if (!IS_ERR(dentry)) {
                        if (!IS_POSIXACL(nd.dentry->d_inode))
                                mode &= ~current->fs->umask;
-                       error = vfs_mkdir(nd.dentry->d_inode, dentry, mode);
+                       error = vfs_mkdir(nd.dentry->d_inode, dentry,
+                               mode, &nd);
                        dput(dentry);
                }
                up(&nd.dentry->d_inode->i_sem);
@@ -1852,9 +1832,10 @@ void dentry_unhash(struct dentry *dentry)
        spin_unlock(&dcache_lock);
 }
 
-int vfs_rmdir(struct inode *dir, struct dentry *dentry)
+int vfs_rmdir(struct inode *dir, struct dentry *dentry,
+       struct nameidata *nd)
 {
-       int error = may_delete(dir, dentry, 1);
+       int error = may_delete(dir, dentry, 1, nd);
 
        if (error)
                return error;
@@ -1916,11 +1897,7 @@ asmlinkage long sys_rmdir(const char __user * pathname)
        dentry = lookup_hash(&nd.last, nd.dentry);
        error = PTR_ERR(dentry);
        if (!IS_ERR(dentry)) {
-               error = mnt_may_unlink(nd.mnt, nd.dentry->d_inode, dentry);
-               if (error)
-                       goto exit2;
-               error = vfs_rmdir(nd.dentry->d_inode, dentry);
-       exit2:
+               error = vfs_rmdir(nd.dentry->d_inode, dentry, &nd);
                dput(dentry);
        }
        up(&nd.dentry->d_inode->i_sem);
@@ -1931,9 +1908,10 @@ exit:
        return error;
 }
 
-int vfs_unlink(struct inode *dir, struct dentry *dentry)
+int vfs_unlink(struct inode *dir, struct dentry *dentry,
+       struct nameidata *nd)
 {
-       int error = may_delete(dir, dentry, 0);
+       int error = may_delete(dir, dentry, 0, nd);
 
        if (error)
                return error;
@@ -1992,13 +1970,10 @@ asmlinkage long sys_unlink(const char __user * pathname)
                /* Why not before? Because we want correct error value */
                if (nd.last.name[nd.last.len])
                        goto slashes;
-               error = mnt_may_unlink(nd.mnt, nd.dentry->d_inode, dentry);
-               if (error)
-                       goto exit2;
                inode = dentry->d_inode;
                if (inode)
                        atomic_inc(&inode->i_count);
-               error = vfs_unlink(nd.dentry->d_inode, dentry);
+               error = vfs_unlink(nd.dentry->d_inode, dentry, &nd);
        exit2:
                dput(dentry);
        }
@@ -2017,9 +1992,10 @@ slashes:
        goto exit2;
 }
 
-int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, int mode)
+int vfs_symlink(struct inode *dir, struct dentry *dentry,
+       const char *oldname, int mode, struct nameidata *nd)
 {
-       int error = may_create(dir, dentry, NULL);
+       int error = may_create(dir, dentry, nd);
 
        if (error)
                return error;
@@ -2061,7 +2037,8 @@ asmlinkage long sys_symlink(const char __user * oldname, const char __user * new
                dentry = lookup_create(&nd, 0);
                error = PTR_ERR(dentry);
                if (!IS_ERR(dentry)) {
-                       error = vfs_symlink(nd.dentry->d_inode, dentry, from, S_IALLUGO);
+                       error = vfs_symlink(nd.dentry->d_inode, dentry,
+                               from, S_IALLUGO, &nd);
                        dput(dentry);
                }
                up(&nd.dentry->d_inode->i_sem);
@@ -2073,7 +2050,8 @@ out:
        return error;
 }
 
-int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
+int vfs_link(struct dentry *old_dentry, struct inode *dir,
+       struct dentry *new_dentry, struct nameidata *nd)
 {
        struct inode *inode = old_dentry->d_inode;
        int error;
@@ -2081,7 +2059,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
        if (!inode)
                return -ENOENT;
 
-       error = may_create(dir, new_dentry, NULL);
+       error = may_create(dir, new_dentry, nd);
        if (error)
                return error;
 
@@ -2150,7 +2128,8 @@ asmlinkage long sys_link(const char __user * oldname, const char __user * newnam
        new_dentry = lookup_create(&nd, 0);
        error = PTR_ERR(new_dentry);
        if (!IS_ERR(new_dentry)) {
-               error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry);
+               error = vfs_link(old_nd.dentry, nd.dentry->d_inode,
+                       new_dentry, &nd);
                dput(new_dentry);
        }
        up(&nd.dentry->d_inode->i_sem);
@@ -2280,14 +2259,14 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        if (old_dentry->d_inode == new_dentry->d_inode)
                return 0;
  
-       error = may_delete(old_dir, old_dentry, is_dir);
+       error = may_delete(old_dir, old_dentry, is_dir, NULL);
        if (error)
                return error;
 
        if (!new_dentry->d_inode)
                error = may_create(new_dir, new_dentry, NULL);
        else
-               error = may_delete(new_dir, new_dentry, is_dir);
+               error = may_delete(new_dir, new_dentry, is_dir, NULL);
        if (error)
                return error;