loop: zero fill bio instead of return -EIO for partial read

commit 8268f5a741 ("deny partial write for loop dev fd") tried to fix the
loop device partial read information leak problem.  But it changed the
semantics of read behavior.  When we read beyond the end of the device we
should get 0 bytes, which is normal behavior, we should not just return
-EIO

Instead of returning -EIO, zero out the bio to avoid information leak in
case of partail read.

Signed-off-by: Dave Young <[email protected]>
Reviewed-by: Jeff Moyer <[email protected]>
Tested-by: Jeff Moyer <[email protected]>
Cc: Dmitry Monakhov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

0 files changed, 0 insertions, 0 deletions