nfs_write_end(): fix handling of short copies

commit c0cf3ef5e0f47e385920450b245d22bead93e7ad upstream.

What matters when deciding if we should make a page uptodate is
not how much we _wanted_ to copy, but how much we actually have
copied.  As it is, on architectures that do not zero tail on
short copy we can leave uninitialized data in page marked uptodate.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 1e6bfdbc1aff4403a194798d3c3928993948710d..0a0b5063e50ee6e1d2708ee29d92f217c025577d 100644 (file)
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -425,7 +425,7 @@ static int nfs_write_end(struct file *file, struct address_space *mapping,
         */
        if (!PageUptodate(page)) {
                unsigned pglen = nfs_page_length(page);
-               unsigned end = offset + len;
+               unsigned end = offset + copied;
 
                if (pglen == 0) {
                        zero_user_segments(page, 0, offset,