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 <[email protected]>
Signed-off-by: Al Viro <[email protected]>
This commit is contained in:
Christoph Hellwig 2010-06-04 11:30:04 +02:00 • committed by Al Viro
commit 2c27c65ed0
21 changed files with 108 additions and 156 deletions

View file

@ -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;
}