check ATTR_SIZE contraints in inode_change_ok

Make sure we check the truncate constraints early on in ->setattr by adding
those checks to inode_change_ok.  Also clean up and document inode_change_ok
to make this obvious.

As a fallout we don't have to call inode_newsize_ok from simple_setsize and
simplify it down to a truncate_setsize which doesn't return an error.  This
simplifies a lot of setattr implementations and means we use truncate_setsize
almost everywhere.  Get rid of fat_setsize now that it's trivial and mark
ext2_setsize static to make the calling convention obvious.

Keep the inode_newsize_ok in vmtruncate for now as all callers need an
audit for its removal anyway.

Note: setattr code in ecryptfs doesn't call inode_change_ok at all and
needs a deeper audit, but that is left for later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 3 insertions, 8 deletions

diff --git a/fs/ufs/truncate.c b/fs/ufs/truncate.c
index 085e11623b7b..34d5cb135320 100644
--- a/fs/ufs/truncate.c
+++ b/fs/ufs/truncate.c
@@ -500,11 +500,6 @@ out:
         return err;
 }
 
-/*
- * TODO:
- *      - truncate case should use proper ordering instead of using
- *        simple_setsize
- */
 int ufs_setattr(struct dentry *dentry, struct iattr *attr)
 {
         struct inode *inode = dentry->d_inode;
@@ -518,9 +513,9 @@ int ufs_setattr(struct dentry *dentry, struct iattr *attr)
         if (ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) {
                 loff_t old_i_size = inode->i_size;
 
-                error = simple_setsize(inode, attr->ia_size);
-                if (error)
-                        return error;
+                /* XXX(truncate): truncate_setsize should be called last */
+                truncate_setsize(inode, attr->ia_size);
+
                 error = ufs_truncate(inode, old_i_size);
                 if (error)
                         return error;