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, 3 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 584cf8ac167a..81296b4e3646 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1233,7 +1233,7 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
         }
 
         /*
-         * This will intentionally not wind up calling simple_setsize(),
+         * This will intentionally not wind up calling truncate_setsize(),
          * since all the work for a size change has been done above.
          * Otherwise, we could get into problems with truncate as
          * ip_alloc_sem is used there to protect against i_size
@@ -2308,12 +2308,12 @@ relock:
                          * blocks outside i_size. Trim these off again.
                          * Don't need i_size_read because we hold i_mutex.
                          *
-                         * XXX(hch): this looks buggy because ocfs2 did not
+                         * XXX(truncate): this looks buggy because ocfs2 did not
                          * actually implement ->truncate.  Take a look at
                          * the new truncate sequence and update this accordingly
                          */
                         if (*ppos + count > inode->i_size)
-                                simple_setsize(inode, inode->i_size);
+                                truncate_setsize(inode, inode->i_size);
                         ret = written;
                         goto out_dio;
                 }