tree d334ecfe630780d495e55443038ab140085373af
parent 44deba5a52576508f27edadf953e435141e2a76a
author Kevin Wolf <kwolf@redhat.com> 1404486688 +0200
committer Kevin Wolf <kwolf@redhat.com> 1405332200 +0200

qed: Make qiov match request size until backing file EOF

If a QED image has a shorter backing file and a read request to
unallocated clusters goes across EOF of the backing file, the backing
file sees a shortened request and the rest is filled with zeros.
However, the original too long qiov was used with the shortened request.

This patch makes the qiov size match the request size, avoiding a
potential buffer overflow in raw-posix.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>