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

@ -169,13 +169,13 @@ int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
mutex_unlock(&f->sem);
jffs2_complete_reservation(c);
/* We have to do the simple_setsize() without f->sem held, since
/* We have to do the truncate_setsize() without f->sem held, since
some pages may be locked and waiting for it in readpage().
We are protected from a simultaneous write() extending i_size
back past iattr->ia_size, because do_truncate() holds the
generic inode semaphore. */
if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size) {
simple_setsize(inode, iattr->ia_size);
truncate_setsize(inode, iattr->ia_size);
inode->i_blocks = (inode->i_size + 511) >> 9;
}